Sample records for flow meter model

  1. Low Flow Vortex Shedding Flow Meter for Hypergolics/all Media

    NASA Technical Reports Server (NTRS)

    Thinh, Ngo Dinh

    1991-01-01

    A family of vortex shedding flow meters, for measurement of hypergol flows, was designed and fabricated. The test loops to evaluate the flow meters for water flow, as well as Freon -113 flow which simulates the hypergolic fluids, were modified and constructed to utilize a pump system which has an output capacity of 200 gpm. Test runs were conducted on the small 1/2 inch model with Freon 113 and on the larger models with water. Results showed that the linearity between the frequency of the vortices and the flow rate of the fluids was very close to that of the turbine flow meter. It is suggested that the vortex shedding flow meter is a possible replacement for the existing turbine type.

  2. Basic study on hot-wire flow meter in forced flow of liquid hydrogen

    NASA Astrophysics Data System (ADS)

    Oura, Y.; Shirai, Y.; Shiotsu, M.; Murakami, K.; Tatsumoto, H.; Naruo, Y.; Nonaka, S.; Kobayashi, H.; Inatani, Y.; Narita, N.

    2014-01-01

    Liquid hydrogen (LH2) is a key issue in a carbon-free energy infrastructure at the energy storage and transportation stage. The typical features of LH2 are low viscosity, large latent heat and small density, compared with other general liquids. It is necessary to measure a mass flow of liquid hydrogen with a simple and compact method, especially in a two phase separate flow condition. We have proposed applying a hot-wire type flow meter, which is usually used a for gas flow meter, to LH2 flow due to the quite low viscosity and density. A test model of a compact LH2 hot-wire flow meter to measure local flow velocities near and around an inside perimeter of a horizontal tube by resistance thermometry was designed and made. The model flow meter consists of two thin heater wires made of manganin fixed in a 10 mm-diameter and 40 mm-length tube flow path made of GFRP. Each rigid heater wire was set twisted by 90 degrees from the inlet to the outlet along the inner wall. In other words, the wires were aslant with regard to the LH2 stream line. The heated wire was cooled by flowing LH2, and the flow velocity was obtained by means of the difference of the cooling characteristic in response to the flow velocity. In this report, we show results on the basic experiments with the model LH2 hot-wire flow meter. First, the heat transfer characteristics of the two heater wires for several LH2 flow velocities were measured. Second, the heating current was controlled to keep the wire temperature constant for various flow velocities. The relations between the flow velocity and the heating current were measured. The feasibility of the proposed model was confirmed.

  3. Weather Impact on Airport Arrival Meter Fix Throughput

    NASA Technical Reports Server (NTRS)

    Wang, Yao

    2017-01-01

    Time-based flow management provides arrival aircraft schedules based on arrival airport conditions, airport capacity, required spacing, and weather conditions. In order to meet a scheduled time at which arrival aircraft can cross an airport arrival meter fix prior to entering the airport terminal airspace, air traffic controllers make regulations on air traffic. Severe weather may create an airport arrival bottleneck if one or more of airport arrival meter fixes are partially or completely blocked by the weather and the arrival demand has not been reduced accordingly. Under these conditions, aircraft are frequently being put in holding patterns until they can be rerouted. A model that predicts the weather impacted meter fix throughput may help air traffic controllers direct arrival flows into the airport more efficiently, minimizing arrival meter fix congestion. This paper presents an analysis of air traffic flows across arrival meter fixes at the Newark Liberty International Airport (EWR). Several scenarios of weather impacted EWR arrival fix flows are described. Furthermore, multiple linear regression and regression tree ensemble learning approaches for translating multiple sector Weather Impacted Traffic Indexes (WITI) to EWR arrival meter fix throughputs are examined. These weather translation models are developed and validated using the EWR arrival flight and weather data for the period of April-September in 2014. This study also compares the performance of the regression tree ensemble with traditional multiple linear regression models for estimating the weather impacted throughputs at each of the EWR arrival meter fixes. For all meter fixes investigated, the results from the regression tree ensemble weather translation models show a stronger correlation between model outputs and observed meter fix throughputs than that produced from multiple linear regression method.

  4. An Investigation of Slurry Fuel Combustion.

    DTIC Science & Technology

    1981-01-01

    tit Lil’ sitas wtae f).4 mm ap.art. w w =Q L-1~ rAn Li w > 0 0- - q The propane gas flow rate was metered withi a Matlieson Model 604 rotameter and...controlled by a Harris Model 2515 pressure regulator with an output capacity of 0-0.69 MPa. The flow rate of the iydrog’en gas was metered with a...propane 3nd hydrogen flows were calibrated with a Precision Scientific Companv wet-test meter (2.83 ml/rev). The fuel drops were mounted with a

  5. Peak expiratory flow profiles delivered by pump systems. Limitations due to wave action.

    PubMed

    Miller, M R; Jones, B; Xu, Y; Pedersen, O F; Quanjer, P H

    2000-06-01

    Pump systems are currently used to test the performance of both spirometers and peak expiratory flow (PEF) meters, but for certain flow profiles the input signal (i.e., requested profile) and the output profile can differ. We developed a mathematical model of wave action within a pump and compared the recorded flow profiles with both the input profiles and the output predicted by the model. Three American Thoracic Society (ATS) flow profiles and four artificial flow-versus-time profiles were delivered by a pump, first to a pneumotachograph (PT) on its own, then to the PT with a 32-cm upstream extension tube (which would favor wave action), and lastly with the PT in series with and immediately downstream to a mini-Wright peak flow meter. With the PT on its own, recorded flow for the seven profiles was 2.4 +/- 1.9% (mean +/- SD) higher than the pump's input flow, and similarly was 2.3 +/- 2.3% higher than the pump's output flow as predicted by the model. With the extension tube in place, the recorded flow was 6.6 +/- 6.4% higher than the input flow (range: 0.1 to 18.4%), but was only 1.2 +/- 2.5% higher than the output flow predicted by the model (range: -0.8 to 5.2%). With the mini-Wright meter in series, the flow recorded by the PT was on average 6.1 +/- 9.1% below the input flow (range: -23.8 to 2. 5%), but was only 0.6 +/- 3.3% above the pump's output flow predicted by the model (range: -5.5 to 3.9%). The mini-Wright meter's reading (corrected for its nonlinearity) was on average 1.3 +/- 3.6% below the model's predicted output flow (range: -9.0 to 1. 5%). The mini-Wright meter would be deemed outside ATS limits for accuracy for three of the seven profiles when compared with the pump's input PEF, but this would be true for only one profile when compared with the pump's output PEF as predicted by the model. Our study shows that the output flow from pump systems can differ from the input waveform depending on the operating configuration. This effect can be predicted with reasonable accuracy using a model based on nonsteady flow analysis that takes account of pressure wave reflections within pump systems.

  6. Energy transfer model and its applications of ultrasonic gas flow-meter under static and dynamic flow rates

    NASA Astrophysics Data System (ADS)

    Fang, Min; Xu, Ke-Jun; Zhu, Wen-Jiao; Shen, Zi-Wen

    2016-01-01

    Most of the ultrasonic gas flow-meters measure the gas flow rate by calculating the ultrasonic transmission time difference between the downstream and upstream. Ultrasonic energy attenuation occurs in the processes of the ultrasonic generation, conversion, transmission, and reception. Additionally, at the same time, the gas flow will also affect the ultrasonic propagation during the measurement, which results in the ultrasonic energy attenuation and the offset of ultrasonic propagation path. Thus, the ultrasonic energy received by the transducer is weaker. When the gas flow rate increases, this effect becomes more apparent. It leads to the measurement accuracy reduced, and the measurement range narrowed. An energy transfer model, where the ultrasonic gas flow-meter under without/with the gas flow, is established by adopting the statistical analysis and curve fitting based on a large amount of experimental data. The static sub model without the gas flow expresses the energy conversion efficiency of ultrasonic gas transducers, and the dynamic sub model with the gas flow reflects the energy attenuation pattern following the flow rate variations. The mathematical model can be used to determine the minimum energy of the excitation signal for meeting the requirement of specific measurement range, and predict the maximum measurable flow rate in the case of fixed energy of excitation signal. Based on the above studies, a method to enhance the excitation signal energy is proposed under the output power of the transmitting circuit being a finite value so as to extend the measurement rage of ultrasonic gas flow-meter.

  7. A mercury flow meter for ion thruster testing. [response time, thermal sensitivity

    NASA Technical Reports Server (NTRS)

    Wilbur, P. J.

    1973-01-01

    The theory of operation of the thermal flow meter is presented, and a theoretical model is used to determine design parameters for a device capable of measuring mercury flows in the range of 0 to 5 gm/hr. Flow meter construction is described. Tests performed using a positive displacement mercury pump as well as those performed with the device in the feed line of an operating thruster are discussed. A flow meter response time of about a minute and a sensitivity of about 10 mv/gm/hr are demonstrated. Additional work to relieve a sensitivity of the device to variations in ambient temperature is indicated to improve its quantitative performance.

  8. Time-of-flight dependency on transducer separation distance in a reflective-path guided-wave ultrasonic flow meter at zero flow conditions.

    PubMed

    Aanes, Magne; Kippersund, Remi Andre; Lohne, Kjetil Daae; Frøysa, Kjell-Eivind; Lunde, Per

    2017-08-01

    Transit-time flow meters based on guided ultrasonic wave propagation in the pipe spool have several advantages compared to traditional inline ultrasonic flow metering. The extended interrogation field, obtained by continuous leakage from guided waves traveling in the pipe wall, increases robustness toward entrained particles or gas in the flow. In reflective-path guided-wave ultrasonic flow meters (GW-UFMs), the flow equations are derived from signals propagating solely in the pipe wall and from signals passing twice through the fluid. In addition to the time-of-flight (TOF) through the fluid, the fluid path experiences an additional time delay upon reflection at the opposite pipe wall due to specular and non-specular reflections. The present work investigates the influence of these reflections on the TOF in a reflective-path GW-UFM as a function of transducer separation distance at zero flow conditions. Two models are used to describe the signal propagation through the system: (i) a transient full-wave finite element model, and (ii) a combined plane-wave and ray-tracing model. The study shows that a range-dependent time delay is associated with the reflection of the fluid path, introducing transmitter-receiver distance dependence. Based on these results, the applicability of the flow equations derived using model (ii) is discussed.

  9. Development of the Dual Aerodynamic Nozzle Model for the NTF Semi-Span Model Support System

    NASA Technical Reports Server (NTRS)

    Jones, Greg S.; Milholen, William E., II; Goodliff, Scott L.

    2011-01-01

    The recent addition of a dual flow air delivery system to the NASA Langley National Transonic Facility was experimentally validated with a Dual Aerodynamic Nozzle semi-span model. This model utilized two Stratford calibration nozzles to characterize the weight flow system of the air delivery system. The weight flow boundaries for the air delivery system were identified at mildly cryogenic conditions to be 0.1 to 23 lbm/sec for the high flow leg and 0.1 to 9 lbm/sec for the low flow leg. Results from this test verified system performance and identified problems with the weight-flow metering system that required the vortex flow meters to be replaced at the end of the test.

  10. Nonlinear model for offline correction of pulmonary waveform generators.

    PubMed

    Reynolds, Jeffrey S; Stemple, Kimberly J; Petsko, Raymond A; Ebeling, Thomas R; Frazer, David G

    2002-12-01

    Pulmonary waveform generators consisting of motor-driven piston pumps are frequently used to test respiratory-function equipment such as spirometers and peak expiratory flow (PEF) meters. Gas compression within these generators can produce significant distortion of the output flow-time profile. A nonlinear model of the generator was developed along with a method to compensate for gas compression when testing pulmonary function equipment. The model and correction procedure were tested on an Assess Full Range PEF meter and a Micro DiaryCard PEF meter. The tests were performed using the 26 American Thoracic Society standard flow-time waveforms as the target flow profiles. Without correction, the pump loaded with the higher resistance Assess meter resulted in ten waveforms having a mean square error (MSE) higher than 0.001 L2/s2. Correction of the pump for these ten waveforms resulted in a mean decrease in MSE of 87.0%. When loaded with the Micro DiaryCard meter, the uncorrected pump outputs included six waveforms with MSE higher than 0.001 L2/s2. Pump corrections for these six waveforms resulted in a mean decrease in MSE of 58.4%.

  11. Two-phase flow characterization based on advanced instrumentation, neural networks, and mathematical modeling

    NASA Astrophysics Data System (ADS)

    Mi, Ye

    1998-12-01

    The major objective of this thesis is focused on theoretical and experimental investigations of identifying and characterizing vertical and horizontal flow regimes in two-phase flows. A methodology of flow regime identification with impedance-based neural network systems and a comprehensive model of vertical slug flow have been developed. Vertical slug flow has been extensively investigated and characterized with geometric, kinematic and hydrodynamic parameters. A multi-sensor impedance void-meter and a multi-sensor magnetic flowmeter were developed. The impedance void-meter was cross-calibrated with other reliable techniques for void fraction measurements. The performance of the impedance void-meter to measure the void propagation velocity was evaluated by the drift flux model. It was proved that the magnetic flowmeter was applicable to vertical slug flow measurements. Separable signals from these instruments allow us to unearth most characteristics of vertical slug flow. A methodology of vertical flow regime identification was developed. Supervised neural network and self-organizing neural network systems were employed. First, they were trained with results from an idealized simulation of impedance in a two-phase mixture. The simulation was mainly based on Mishima and Ishii's flow regime map, the drift flux model, and the newly developed model of slug flow. Then, these trained systems were tested with impedance signals. The results showed that the neural network systems were appropriate classifiers of vertical flow regimes. The theoretical models and experimental databases used in the simulation were reliable. Furthermore, this approach was applied successfully to horizontal flow identification. A comprehensive model was developed to predict important characteristics of vertical slug flow. It was realized that the void fraction of the liquid slug is determined by the relative liquid motion between the Taylor bubble tail and the Taylor bubble wake. Relying on this understanding and experimental results, a special relationship was built for the void fraction of the liquid slug. The prediction of the void fraction of the liquid slug was considerably improved. Experimental characterization of vertical slug flows was performed extensively with the impedance void-meter and the magnetic flowmeter. The theoretical predictions were compared with the experimental results. The agreements between them are very satisfactory.

  12. Robust, non-invasive methods for metering groundwater well extraction in remote environments

    NASA Astrophysics Data System (ADS)

    Bulovic, Nevenka; Keir, Greg; McIntyre, Neil

    2017-04-01

    Quantifying the rate of extraction from groundwater wells can be essential for regional scale groundwater management and impact assessment. This is especially the case in regions heavily dependent on groundwater such as the semi-arid Surat and Bowen Basins in Queensland, Australia. Of the 30 000+ groundwater wells in this area, the majority of which are used for stock watering and domestic purposes, almost none have flow metering devices installed. As part of a research project to estimate regional groundwater extraction, we have undertaken a small scale flow metering program on a selected set of wells. Conventional in-line flow meters were unsuitable for our project, as both non-invasiveness and adaptability / suitability to a variety of discharge pipe characteristics was critical. We describe the use of two metering technologies not widely used in groundwater applications, non-invasive, clamp-on ultrasonic transit time flow meters and tipping bucket flow meters, as semi-permanent installations on discharge pipes of various artesian and sub-artesian groundwater wells. We present examples of detailed extraction rate time-series, which are of particular value in developing predictive models of water well extraction in data limited areas where water use dynamics and drivers are poorly understood. We conclude by discussing future project trajectories, which include expansion of the monitoring network through development of novel metering techniques and telemetry across large areas of poor connectivity.

  13. How to use your peak flow meter

    MedlinePlus

    Peak flow meter - how to use; Asthma - peak flow meter; Reactive airway disease - peak flow meter; Bronchial asthma - peak flow meter ... your airways are narrowed and blocked due to asthma, your peak flow values drop. You can check ...

  14. A two-fluid model for avalanche and debris flows.

    PubMed

    Pitman, E Bruce; Le, Long

    2005-07-15

    Geophysical mass flows--debris flows, avalanches, landslides--can contain O(10(6)-10(10)) m(3) or more of material, often a mixture of soil and rocks with a significant quantity of interstitial fluid. These flows can be tens of meters in depth and hundreds of meters in length. The range of scales and the rheology of this mixture presents significant modelling and computational challenges. This paper describes a depth-averaged 'thin layer' model of geophysical mass flows containing a mixture of solid material and fluid. The model is derived from a 'two-phase' or 'two-fluid' system of equations commonly used in engineering research. Phenomenological modelling and depth averaging combine to yield a tractable set of equations, a hyperbolic system that describes the motion of the two constituent phases. If the fluid inertia is small, a reduced model system that is easier to solve may be derived.

  15. The Peak Flow Working Group: test of portable peak flow meters by explosive decompression.

    PubMed

    Pedersen, O F; Miller, M R

    1997-02-01

    In 1991, 50 new Vitalograph peak flow meters and 27 previously used mini-Wright peak flow meters were tested at three peak flows by use of a calibrator applying explosive decompression. The mini-Wright peak flow meters were also compared with eight new meters. For both makes of meter there was an excellent within-meter and between-meter variation. The accuracy, however, was poor, with a maximal overestimation of true flows of 50 and 70 L.min-1 in the interval from 200 to 400 L.min-1 for the Vitalograph and mini-Wright meters, respectively. The deviation is explained by the physical characteristics of the variable orifice peak flow meters. They have been supplied with equidistant scales, which give non-linear readings.

  16. Simulation of hydrodynamics, temperature, and dissolved oxygen in Beaver Lake, Arkansas, 1994-1995

    USGS Publications Warehouse

    Haggard, Brian; Green, W. Reed

    2002-01-01

    The tailwaters of Beaver Lake and other White River reservoirs support a cold-water trout fishery of significant economic yield in northwestern Arkansas. The Arkansas Game and Fish Commission has requested an increase in existing minimum flows through the Beaver Lake dam to increase the amount of fishable waters downstream. Information is needed to assess the impact of additional minimum flows on temperature and dissolved-oxygen qualities of reservoir water above the dam and the release water. A two-dimensional, laterally averaged hydrodynamic, thermal and dissolved-oxygen model was developed and calibrated for Beaver Lake, Arkansas. The model simulates surface-water elevation, currents, heat transport and dissolved-oxygen dynamics. The model was developed to assess the impacts of proposed increases in minimum flows from 1.76 cubic meters per second (the existing minimum flow) to 3.85 cubic meters per second (the additional minimum flow). Simulations included assessing (1) the impact of additional minimum flows on tailwater temperature and dissolved-oxygen quality and (2) increasing initial water-surface elevation 0.5 meter and assessing the impact of additional minimum flow on tailwater temperatures and dissolved-oxygen concentrations. The additional minimum flow simulation (without increasing initial pool elevation) appeared to increase the water temperature (<0.9 degrees Celsius) and decrease dissolved oxygen concentration (<2.2 milligrams per liter) in the outflow discharge. Conversely, the additional minimum flow plus initial increase in pool elevation (0.5 meter) simulation appeared to decrease outflow water temperature (0.5 degrees Celsius) and increase dissolved oxygen concentration (<1.2 milligrams per liter) through time. However, results from both minimum flow scenarios for both water temperature and dissolved oxygen concentration were within the boundaries or similar to the error between measured and simulated water column profile values.

  17. Optimization of radioactive sources to achieve the highest precision in three-phase flow meters using Jaya algorithm.

    PubMed

    Roshani, G H; Karami, A; Khazaei, A; Olfateh, A; Nazemi, E; Omidi, M

    2018-05-17

    Gamma ray source has very important role in precision of multi-phase flow metering. In this study, different combination of gamma ray sources (( 133 Ba- 137 Cs), ( 133 Ba- 60 Co), ( 241 Am- 137 Cs), ( 241 Am- 60 Co), ( 133 Ba- 241 Am) and ( 60 Co- 137 Cs)) were investigated in order to optimize the three-phase flow meter. Three phases were water, oil and gas and the regime was considered annular. The required data was numerically generated using MCNP-X code which is a Monte-Carlo code. Indeed, the present study devotes to forecast the volume fractions in the annular three-phase flow, based on a multi energy metering system including various radiation sources and also one NaI detector, using a hybrid model of artificial neural network and Jaya Optimization algorithm. Since the summation of volume fractions is constant, a constraint modeling problem exists, meaning that the hybrid model must forecast only two volume fractions. Six hybrid models associated with the number of used radiation sources are designed. The models are employed to forecast the gas and water volume fractions. The next step is to train the hybrid models based on numerically obtained data. The results show that, the best forecast results are obtained for the gas and water volume fractions of the system including the ( 241 Am- 137 Cs) as the radiation source. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Non-contact ultrasonic gas flow metering using air-coupled leaky Lamb waves.

    PubMed

    Fan, Zichuan; Jiang, Wentao; Wright, William M D

    2018-04-23

    This paper describes a completely non-contact ultrasonic method of gas flow metering using air-coupled leaky Lamb waves. To show proof of principle, a simplified representation of gas flow in a duct, comprising two separated thin isotropic plates with a gas flowing between them, has been modelled and investigated experimentally. An airborne compression wave emitted from an air-coupled capacitive ultrasonic transducer excited a leaky Lamb wave in the first plate in a non-contact manner. The leakage of this Lamb wave crossed the gas flow at an angle between the two plates as a compression wave, and excited a leaky Lamb wave in the second plate. An air-coupled capacitive ultrasonic transducer on the opposite side of this second plate then detected the airborne compression wave leakage from the second Lamb wave. As the gas flow shifted the wave field between the two plates, the point of Lamb wave excitation in the second plate was displaced in proportion to the gas flow rate. Two such measurements, in opposite directions, formed a completely non-contact contra-propagating Lamb wave flow meter, allowing measurement of the flow velocity between the plates. A COMSOL Multiphysics® model was used to visualize the wave fields, and accurately predicted the time differences that were then measured experimentally. Experiments using different Lamb wave frequencies and plate materials were also similarly verified. This entirely non-contact airborne approach to Lamb wave flow metering could be applied in place of clamp-on techniques in thin-walled ducts or pipes. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Proof-of-principle demonstration of a virtual flow meter-based transducer for gaseous helium monitoring in particle accelerator cryogenics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arpaia, P.; Technology Department, European Organization for Nuclear Research; Blanco, E.

    2015-07-15

    A transducer based on a virtual flow meter is proposed for monitoring helium distribution and consumption in cryogenic systems for particle accelerators. The virtual flow meter allows technical and economical constraints, preventing installation of physical instruments in all the needed measurement points, to be overcome. Virtual flow meter performance for the alternative models of Samson [ http://www.samson.de (2015)] and Sereg-Schlumberger [ http://www.slb.com/ (2015)] is compared with the standard IEC 60534-2-1 [Industrial-process control valves—Part 2-1: Flow capacity—sizing equations for fluid flow under installed conditions (2011), https://webstore.iec.ch/publication/2461], for a large temperature range, for both gaseous and liquid helium phases, and for differentmore » pressure drops. Then, the calibration function of the transducer is derived. Finally, the experimental validation for the helium gaseous state on the test station for superconducting magnets in the laboratory SM18 [Pirotte et al., AIP Conf. Proc. 1573, 187 (2014)] at CERN is reported.« less

  20. LSST (Hoop/Column) Maypole Antenna Development Program, phase 1, part 2

    NASA Technical Reports Server (NTRS)

    Sullivan, M. R.

    1982-01-01

    Cable technology is discussed. Manufacturing flow and philosophy are considered. Acceptance, gratification and flight tests are discussed. Fifteen-meter and fifty-meter models are considered. An economic assessment is included.

  1. LSST (Hoop/Column) Maypole Antenna Development Program, phase 1, part 2

    NASA Astrophysics Data System (ADS)

    Sullivan, M. R.

    1982-06-01

    Cable technology is discussed. Manufacturing flow and philosophy are considered. Acceptance, gratification and flight tests are discussed. Fifteen-meter and fifty-meter models are considered. An economic assessment is included.

  2. Balanced Flow Meters without Moving Parts

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.; VanBuskirk, Paul

    2008-01-01

    Balanced flow meters are recent additions to an established class of simple, rugged flow meters that contain no moving parts in contact with flow and are based on measurement of pressure drops across objects placed in flow paths. These flow meters are highly accurate, minimally intrusive, easily manufacturable, and reliable. A balanced flow meter can be easily mounted in a flow path by bolting it between conventional pipe flanges. A balanced flow meter can be used to measure the flow of any of a variety of liquids or gases, provided that it has been properly calibrated. Relative to the standard orifice-plate flow meter, the balanced flow meter introduces less turbulence and two times less permanent pressure loss and is therefore capable of offering 10 times greater accuracy and repeatability with less dissipation of energy. A secondary benefit of the reduction of turbulence is the reduction of vibration and up to 15 times less acoustic noise generation. Both the balanced flow meter and the standard orifice-plate flow meter are basically disks that contain holes and are instrumented with pressure transducers on their upstream and downstream faces. The most obvious difference between them is that the standard orifice plate contains a single, central hole while the balanced flow meter contains multiple holes. The term 'balanced' signifies that in designing the meter, the sizes and locations of the holes are determined in an optimization procedure that involves balancing of numerous factors, including volumetric flow, mass flow, dynamic pressure, kinetic energy, all in an effort to minimize such undesired effects as turbulence, pressure loss, dissipation of kinetic energy, and non-repeatability and nonlinearity of response over the anticipated range of flow conditions. Due to proper balancing of these factors, recent testing demonstrated that the balanced flow-meter performance was similar to a Venturi tube in both accuracy and pressure recovery, but featured reduced cost and pipe-length requirements.

  3. Aerodynamic and Acoustic Tests of a 1/15 Scale Model Dry Cooled Jet Aircraft Runup Noise Suppression System,

    DTIC Science & Technology

    1975-10-01

    sophisticated wet-cooled systems having scrubbers and their associated water treatment facilities . The United States Navy has recognized these Hush... venturi meter air inlet to measure the pumped air flow and the exhaust enclosure is provided with suitable ports for the flow to exit. The test program...constantan thermo- couple and venturi flow meters were used to measure the aerodynamic/thermo- dynamic information required from the tests (pressure

  4. Revisiting the accuracy of peak flow meters: a double-blind study using formal methods of agreement.

    PubMed

    Nazir, Z; Razaq, S; Mir, S; Anwar, M; Al Mawlawi, G; Sajad, M; Shehab, A; Taylor, R S

    2005-05-01

    There is widespread use of peak flow meters in both hospitals and general practice. Previous studies to assess peak flow meter accuracy have shown significant differences in the values obtained from different meters. However, many of these studies did not use human subjects for peak flow measurements and did not compare meters of varying usage. In this study human subjects have been used with meters of varying usage. Participants were tested using two new (meters A and C) and one old peak flow meter (meter B) in random order. The study was double-blinded. Participants were recruited from the university campus. Four hundred and nine individuals participated. The difference between peak flow means of A and B was -9.93 l/min (95% CI: -12.37 to -7.48, P<0.0001). The difference between peak flow means of B and C was 20.08 l/min (95% CI: 17.85-22.29, P<0.0001). The difference between peak flow means of A and C was 10.15 l/min (95% CI: 7.68-12.61, P<0.0001). There was a significant difference between the values obtained from the new and old peak flow meters and also between the two new peak flow meters. We conclude that there is need for caution in interchangeably using flow meters in clinical practice.

  5. Fluid Flow Technology that Measures Up

    NASA Technical Reports Server (NTRS)

    2004-01-01

    From 1994 to 1996, NASA s Marshall Space Flight Center conducted a Center Director's Discretionary Fund research effort to apply artificial intelligence technologies to the health management of plant equipment and space propulsion systems. Through this effort, NASA established a business relationship with Quality Monitoring and Control (QMC), of Kingwood, Texas, to provide hardware modeling and artificial intelligence tools. Very detailed and accurate Space Shuttle Main Engine (SSME) analysis and algorithms were jointly created, which identified several missing, critical instrumentation needs for adequately evaluating the engine health status. One of the missing instruments was a liquid oxygen (LOX) flow measurement. This instrument was missing since the original SSME included a LOX turbine flow meter that failed during a ground test, resulting in considerable damage for NASA. New balanced flow meter technology addresses this need with robust, safe, and accurate flow metering hardware.

  6. 40 CFR 1065.225 - Intake-air flow meter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... flow meter. (a) Application. You may use an intake-air flow meter in combination with a chemical..., you may use an intake-air flow meter signal that does not give the actual value of raw exhaust, as... requirements. We recommend that you use an intake-air flow meter that meets the specifications in Table 1 of...

  7. Repeatability and oblique flow response characteristics of current meters

    USGS Publications Warehouse

    Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.; ,

    1993-01-01

    Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement of point velocities in streams and rivers were tested. Meters were tested for repeatability and response to oblique flows. Both horizontal- and vertical-axis meters were found to under- and over-register oblique flows with errors generally increasing as the velocity and angle of flow increased. For the oblique flow tests, magnitude of errors were smallest for horizontal-axis meters. Repeatability of all meters tested was good, with the horizontal- and vertical-axis meters performing similarly.

  8. Vortex shedding flow meter performance at high flow velocities

    NASA Technical Reports Server (NTRS)

    Siegwarth, J. D.

    1986-01-01

    In some of the ducts of the Space Shuttle Main Engine (SSME), the maximum liquid oxygen flow velocities approach 10 times those at which liquid flow measurements are normally made. The hydrogen gas flow velocities in other ducts exceed the maximum for gas flow measurement by more than a factor of 3. The results presented here show from water flow tests that vortex shedding flow meters of the appropriate design can measure water flow to velocities in excess of 55 m/s, which is a Reynolds number of about 2 million. Air flow tests have shown that the same meter can measure flow to a Reynolds number of at least 22 million. Vortex shedding meters were installed in two of the SSME ducts and tested with water flow. Narrow spectrum lines were obtained and the meter output frequencies were proportional to flow to + or - 0.5% or better over the test range with no flow conditioning, even though the ducts had multiple bends preceeding the meter location. Meters with the shedding elements only partially spanning the pipe and some meters with ring shaped shedding elements were also tested.

  9. Increasing Helicity to Achieve a Dynamo State on the Three-Meter Model of the Earth's Core

    NASA Astrophysics Data System (ADS)

    Rojas, R.; Perevalov, A.; Lathrop, D. P.

    2017-12-01

    Dynamo theory describes the generation of magnetic fields in the flows of conducting fluids, for example, in stars and planetary cores. Spherical Couette flows, which are flows between two concentric and independently rotating spheres, is one of the experimental models for achieving this task in the laboratory. We have performed dynamo state search in our three-meter spherical-Couette model reaching up to Reynolds number near 108 with amplifications of the field between 10-30% but without a self-sustained dynamo magnetic field. A recent numerical work [K. Finke and A. Tilgner. Phys. Rev. E, 86:016310, Jul 2012] suggested that a roughened inner core reduces the threshold for dynamo action. The mean flow would have more poloidal component than the one we are generating with our current smooth sphere setup. With baffles flow would be expelled radially outward on the equatorial plane and returned at the poles, with opposite helicities in the two hemispheres. Baffles welded on our smooth inner sphere are proposed to achieve this task. We are working to perform experiments on a scaled water model of our experimental setup with Reynolds number near 105 to measure the helicity improvements of different baffle designs in support of upcoming Three-Meter modifications. We gratefully acknowledge support from NSF EAR-1417148.

  10. A basin-scale approach for assessing water resources in a semiarid environment: San Diego region, California and Mexico

    USGS Publications Warehouse

    Flint, L.E.; Flint, A.L.; Stolp, B.J.; Danskin, W.R.

    2012-01-01

    Many basins throughout the world have sparse hydrologic and geologic data, but have increasing demands for water and a commensurate need for integrated understanding of surface and groundwater resources. This paper demonstrates a methodology for using a distributed parameter water-balance model, gaged surface-water flow, and a reconnaissance-level groundwater flow model to develop a first-order water balance. Flow amounts are rounded to the nearest 5 million cubic meters per year. The San Diego River basin is 1 of 5 major drainage basins that drain to the San Diego coastal plain, the source of public water supply for the San Diego area. The distributed parameter water-balance model (Basin Characterization Model) was run at a monthly timestep for 1940–2009 to determine a median annual total water inflow of 120 million cubic meters per year for the San Diego region. The model was also run specifically for the San Diego River basin for 1982–2009 to provide constraints to model calibration and to evaluate the proportion of inflow that becomes groundwater discharge, resulting in a median annual total water inflow of 50 million cubic meters per year. On the basis of flow records for the San Diego River at Fashion Valley (US Geological Survey gaging station 11023000), when corrected for upper basin reservoir storage and imported water, the total is 30 million cubic meters per year. The difference between these two flow quantities defines the annual groundwater outflow from the San Diego River basin at 20 million cubic meters per year. These three flow components constitute a first-order water budget estimate for the San Diego River basin. The ratio of surface-water outflow and groundwater outflow to total water inflow are 0.6 and 0.4, respectively. Using total water inflow determined using the Basin Characterization Model for the entire San Diego region and the 0.4 partitioning factor, groundwater outflow from the San Diego region, through the coastal plain aquifer to the Pacific Ocean, is calculated to be approximately 50 million cubic meters per year. The area-scale assessment of water resources highlights several hydrologic features of the San Diego region. Groundwater recharge is episodic; the Basin Characterization Model output shows that 90 percent of simulated recharge occurred during 3 percent of the 1982–2009 period. The groundwater aquifer may also be quite permeable. A reconnaissance-level groundwater flow model for the San Diego River basin was used to check the water budget estimates, and the basic interaction of the surface-water and groundwater system, and the flow values, were found to be reasonable. Horizontal hydraulic conductivity values of the volcanic and metavolcanic bedrock in San Diego region range from 1 to 10 m per day. Overall, results establish an initial hydrologic assessment formulated on the basis of sparse hydrologic data. The described flow variability, extrapolation, and unique characteristics represent a realistic view of current (2012) hydrologic understanding for the San Diego region.

  11. Complete energetic description of hydrokinetic turbine impact on flow channel dynamics

    NASA Astrophysics Data System (ADS)

    Brasseale, E.; Kawase, M.

    2016-02-01

    Energy budget analysis on tidal channels quantifies and demarcates the impacts of marine renewables on environmental fluid dynamics. Energy budget analysis assumes the change in total kinetic energy within a volume of fluid can be described by the work done by each force acting on the flow. In a numerically simulated channel, the balance between energy change and work done has been validated up to 5% error.The forces doing work on the flow include pressure, turbulent dissipation, and stress from the estuary floor. If hydrokinetic turbines are installed in an estuarine channel to convert tidal energy into usable power, the dynamics of the channel change. Turbines provide additional pressure work against the flow of the channel which will slow the current and lessen turbulent dissipation and bottom stress. These losses may negatively impact estuarine circulation, seafloor scour, and stratification.The environmental effects of turbine deployment have been quantified using a three dimensional, Reynolds-averaged, Navier-Stokes model of an idealized flow channel situated between the ocean and a large estuarine basin. The channel is five kilometers wide, twenty kilometers long and fifty meters deep, and resolved to a grid size of 10 meters by 10 meters by 1 meter. Tidal currents are simulated by an initial difference in sea surface height across the channel of 160 centimeters from the channel entrance to the channel exit. This creates a pressure gradient which drives flow through the channel. Tidal power turbines are represented as disks that force the channel in proportion to the strength of the current. Three tidal turbines twenty meters in diameters have been included in the model to simulate the impacts of a pilot scale test deployment.This study is the first to appreciate the energetic impact of marine renewables in a three dimensional model through the energy equation's constituent terms. This study provides groundwork for understanding and predicting the environmental impacts of marine renewables.

  12. 40 CFR 1065.640 - Flow meter calibration calculations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Flow meter calibration calculations... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.640 Flow meter calibration calculations. This section describes the calculations for calibrating various flow meters. After...

  13. Flow Meter

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Hedland Flow Meters manufactures a complete line of flow meters used in industrial operations to monitor the flow of oil, water or other liquids, air and other compressed gases, including caustics or corrosive liquids/gases. The company produces more than 1,000 types of flow meters featuring rugged construction, simplicity of installation and the ability to operate in any position.

  14. 40 CFR 1065.230 - Raw exhaust flow meter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... flow meter. (a) Application. You may use measured raw exhaust flow, as follows: (1) Use the actual... the following cases, you may use a raw exhaust flow meter signal that does not give the actual value... consumed. (b) Component requirements. We recommend that you use a raw-exhaust flow meter that meets the...

  15. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  16. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  17. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  18. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  19. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  20. Simulation of flow and sediment mobility using a multidimensional flow model for the White Sturgeon critical-habitat reach, Kootenai River near Bonners Ferry, Idaho

    USGS Publications Warehouse

    Barton, Gary J.; McDonald, Richard R.; Nelson, Jonathan M.; Dinehart, Randal L.

    2005-01-01

    In 1994, the Kootenai River white sturgeon (Acipenser transmontanus) was listed as an Endangered Species as a direct result of two related observations. First, biologists observed that the white sturgeon population in the Kootenai River was declining. Second, they observed a decline in recruitment of juvenile sturgeon beginning in the 1950s with an almost total absence of recruitment since 1974, following the closure of Libby Dam in 1972. This second observation was attributed to changes in spawning and (or) rearing habitat resulting from alterations in the physical habitat, including flow regime, sediment-transport regime, and bed morphology of the river. The Kootenai River White Sturgeon Recovery Team was established to find and implement ways to improve spawning and rearing habitat used by white sturgeon. They identified the need to develop and apply a multidimensional flow model to certain reaches of the river to quantify physical habitat in a spatially distributed manner. The U.S. Geological Survey has addressed these needs by developing, calibrating, and validating a multidimensional flow model used to simulate streamflow and sediment mobility in the white sturgeon critical-habitat reach of the Kootenai River. This report describes the model and limitations, presents the results of a few simple simulations, and demonstrates how the model can be used to link physical characteristics of streamflow to biological or other habitat data. This study was conducted in cooperation with the Kootenai Tribe of Idaho along a 23-kilometer reach of the Kootenai River, including the white sturgeon spawning reach near Bonners Ferry, Idaho that is about 108 to 131 kilometers below Libby Dam. U.S. Geological Survey's MultiDimensional Surface-Water Modeling System was used to construct a flow model for the critical-habitat reach of the Kootenai River white sturgeon, between river kilometers 228.4 and 245.9. Given streamflow, bed roughness, and downstream water-surface elevation, the model computes the velocity field, water-surface elevations, and boundary shear stress throughout the modeled reach. The 17.5 kilometer model reach was subdivided into two segments on the basis of predominant grain size: a straight reach with a sand, gravel, and cobble substrate located between the upstream model boundary at river kilometer 245.9 and the upstream end of Ambush Rock at river kilometer 244.6, and a meandering reach with a predominately sand substrate located between upstream end of Ambush Rock and the downstream model boundary at river kilometer 228.4. Model cell size in the x and y (horizontal) dimensions is 5 meters by 5 meters along the computational grid centerline with 15 nodes in the z (vertical) dimension. The model was calibrated to historical streamflows evenly distributed between 141.6 and 2,548.9 cubic meters per second. The model was validated by comparing simulated velocities with velocities measured at 15 cross sections during steady streamflow. These 15 cross sections were each measured multiple (7-13) times to obtain velocities suitable for comparison to the model results. Comparison of modeled and measured velocities suggests that the model does a good job of reproducing flow patterns in the river, although some discrepancies were noted. The model was used to simulate water-surface elevation, depth, velocity, bed shear stress, and sediment mobility for Kootenai River streamflows of 170, 566, 1,130, 1,700, and 2,270 cubic meters per second (6,000, 20,000, 40,000, 60,000, and 80,000 cubic feet per second). The three lowest streamflow simulations represent a range of typical river conditions before and since the construction of Libby Dam, and the highest streamflow simulation (2,270 cubic meters per second) is approximately equal to the annual median peak streamflow prior to emplacement of Libby Dam in 1972. Streamflow greater than 566 cubic meters per second were incrementally increased by 570 cubic meters per second. For each

  1. 40 CFR 98.423 - Calculating CO2 supply.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Calculate the annual mass of CO2 captured, extracted, imported, or exported through each flow meter in... flow meters are used, you shall calculate the annual mass of CO2 for all flow meters according to the procedures specified in paragraph (a)(3) of this section. (1) For each mass flow meter, you shall calculate...

  2. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  3. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  4. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  5. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  6. Accuracy of mini peak flow meters in indicating changes in lung function in children with asthma.

    PubMed Central

    Sly, P. D.; Cahill, P.; Willet, K.; Burton, P.

    1994-01-01

    OBJECTIVE--To assess whether mini flow meters used to measure peak expiratory flow can track changes in lung function and indicate clinically important changes. DESIGN--Comparison of measurements with a spirometer and different brands of mini flow meter; the meters were allocated to subjects haphazardly. SUBJECTS--12 boys with asthma aged 11 to 17 attending boarding school. MAIN OUTCOME MEASURES--Peak expiratory flow measured twice daily for three months with a spirometer and at least one of four brands of mini flow meter. RESULTS--The relation between changes in lung function measured with the spirometer and those measured with the mini flow meters was generally poor. In all, 26 episodes (range 1-3 in an individual child) of clinically important deterioration in lung function were detected from the records obtained with the spirometer. One mini flow meter detected six of 19 episodes, one detected six of 15, one detected six of 18, and one detected three of 21. CONCLUSIONS--Not only are the absolute values of peak expiratory flow obtained with mini flow meters inaccurate but the clinical message may also be incorrect. These findings do not imply that home monitoring of peak expiratory flow has no place in the management of childhood asthma but that the values obtained should be interpreted cautiously. PMID:8148680

  7. Low flow vortex shedding flowmeter

    NASA Technical Reports Server (NTRS)

    Waugaman, Charles J.

    1989-01-01

    The purpose was to continue a development project on a no moving parts vortex shedding flowmeter used for flow measurement of hypergols. The project involved the design and construction of a test loop to evaluate the meter for flow of Freon which simulates the hypergol fluids. Results were obtained on the output frequency characteristics of the flow meter as a function of flow rate. A family of flow meters for larger size lines and ranges of flow was sized based on the results of the tested meter.

  8. LiDAR-Derived Flood-Inundation Maps for Real-Time Flood-Mapping Applications, Tar River Basin, North Carolina

    USGS Publications Warehouse

    Bales, Jerad D.; Wagner, Chad R.; Tighe, Kirsten C.; Terziotti, Silvia

    2007-01-01

    Flood-inundation maps were created for selected streamgage sites in the North Carolina Tar River basin. Light detection and ranging (LiDAR) data with a vertical accuracy of about 20 centimeters, provided by the Floodplain Mapping Information System of the North Carolina Floodplain Mapping Program, were processed to produce topographic data for the inundation maps. Bare-earth mass point LiDAR data were reprocessed into a digital elevation model with regularly spaced 1.5-meter by 1.5-meter cells. A tool was developed as part of this project to connect flow paths, or streams, that were inappropriately disconnected in the digital elevation model by such features as a bridge or road crossing. The Hydraulic Engineering Center-River Analysis System (HEC-RAS) model, developed by the U.S. Army Corps of Engineers, was used for hydraulic modeling at each of the study sites. Eleven individual hydraulic models were developed for the Tar River basin sites. Seven models were developed for reaches with a single gage, and four models were developed for reaches of the Tar River main stem that receive flow from major gaged tributaries, or reaches in which multiple gages were near one another. Combined, the Tar River hydraulic models included 272 kilometers of streams in the basin, including about 162 kilometers on the Tar River main stem. The hydraulic models were calibrated to the most current stage-discharge relations at 11 long-term streamgages where rating curves were available. Medium- to high-flow discharge measurements were made at some of the sites without rating curves, and high-water marks from Hurricanes Fran and Floyd were available for high-stage calibration. Simulated rating curves matched measured curves over the full range of flows. Differences between measured and simulated water levels for a specified flow were no more than 0.44 meter and typically were less. The calibrated models were used to generate a set of water-surface profiles for each of the 11 modeled reaches at 0.305-meter increments for water levels ranging from bankfull to approximately the highest recorded water level at the downstream-most gage in each modeled reach. Inundated areas were identified by subtracting the water-surface elevation in each 1.5-meter by 1.5-meter grid cell from the land-surface elevation in the cell through an automated routine that was developed to identify all inundated cells hydraulically connected to the cell at the downstream-most gage in the model domain. Inundation maps showing transportation networks and orthoimagery were prepared for display on the Internet. These maps also are linked to the U.S. Geological Survey North Carolina Water Science Center real-time streamflow website. Hence, a user can determine the near real-time stage and water-surface elevation at a U.S. Geological Survey streamgage site in the Tar River basin and link directly to the flood-inundation maps for a depiction of the estimated inundated area at the current water level. Although the flood-inundation maps represent distinct boundaries of inundated areas, some uncertainties are associated with these maps. These are uncertainties in the topographic data for the hydraulic model computational grid and inundation maps, effective friction values (Manning's n), model-validation data, and forecast hydrographs, if used. The Tar River flood-inundation maps were developed by using a steady-flow hydraulic model. This assumption clearly has less of an effect on inundation maps produced for low flows than for high flows when it typically takes more time to inundate areas. A flood in which water levels peak and fall slowly most likely will result in more inundation than a similar flood in which water levels peak and fall quickly. Limitations associated with the steady-flow assumption for hydraulic modeling vary from site to site. The one-dimensional modeling approach used in this study resulted in good agreement between measurements and simulations. T

  9. 75 FR 42330 - Elemental Mercury Used in Flow Meters, Natural Gas Manometers, and Pyrometers; Significant New...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ..., the sale of mercury-containing flow meters is banned in six states: California, Maine, Massachusetts... Elemental Mercury Used in Flow Meters, Natural Gas Manometers, and Pyrometers; Significant New Use Rule... mercury (CAS No. 7439-97-6) for use in flow meters, natural gas manometers, and pyrometers, except for use...

  10. Performance of Thermal Mass Flow Meters in a Variable Gravitational Environment

    NASA Technical Reports Server (NTRS)

    Brooker, John E.; Ruff, Gary A.

    2004-01-01

    The performance of five thermal mass flow meters, MKS Instruments 179A and 258C, Unit Instruments UFM-8100, Sierra Instruments 830L, and Hastings Instruments HFM-200, were tested on the KC-135 Reduced Gravity Aircraft in orthogonal, coparallel, and counterparallel orientations relative to gravity. Data was taken throughout the parabolic trajectory where the g-level varied from 0.01 to 1.8 times normal gravity. Each meter was calibrated in normal gravity in the orthogonal position prior to flight followed by ground testing at seven different flow conditions to establish a baseline operation. During the tests, the actual flow rate was measured independently using choked-flow orifices. Gravitational acceleration and attitude had a unique effect on the performance of each meter. All meters operated within acceptable limits at all gravity levels in the calibrated orthogonal position. However, when operated in other orientations, the deviations from the reference flow became substantial for several of the flow meters. Data analysis indicated that the greatest source of error was the effect of orientation, followed by the gravity level. This work emphasized that when operating thermal flow meters in a variable gravity environment, it is critical to orient the meter in the same direction relative to gravity in which it was calibrated. Unfortunately, there was no test in normal gravity that could predict the performance of a meter in reduced gravity. When operating in reduced gravity, all meters indicated within 5 percent of the full scale reading at all flow conditions and orientations.

  11. Intravenous fluid flow meter concept for zero gravity environment

    NASA Technical Reports Server (NTRS)

    Miller, C. G.

    1972-01-01

    Measuring chamber, included in infusion-set tubing, and peristaltic flow meter concept can be incorporated into flow meter that measures fluid flow rates between 100 and 600 cu cm per hour and at the same time maintains sterilization.

  12. Analysis of tests of subsurface injection, storage, and recovery of freshwater in the lower Floridan aquifer, Okeechobee County, Florida

    USGS Publications Warehouse

    Quinones-Aponte, Vicente; Kotun, Kevin; Whitley, J.F.

    1996-01-01

    A series of freshwater subsurface injection, storage, and recovery tests were conducted at an injection-well site near Lake Okeechobee in Okeechobee County, Florida, to assess the recoverability of injected canal water from the Lower Floridan aquifer. At the study site, the Lower Floridan aquifer is characterized as having four local, relatively independent, high-permeability flow zones (389 to 398 meters, 419 to 424 meters, 456 to 462 meters, and 472 to 476 meters below sea level). Four subsurface injection, storage, and recovery cycles were performed at the Lake Okeechobee injection-well site in which volumes of water injected ranged from about 387,275 to 1,343,675 cubic meters for all the cycles, and volumes of water recovered ranged from about 106,200 to 484,400 cubic meters for cycles 1, 2, and 3. The recovery efficiency for successive cycles 2 and 3 increased from 22 to 36 percent and is expected to continue increasing with additional cycles. A comparison of chloride concentration breakthrough curves at the deep monitor well (located about 171 meters from the injection well) for cycles 1, 4, and test no. 4 (from a previous study) revealed unexpected finings. One significant result was that the concentration asymptote, expected to be reached at concentration levels equivalent or close to the injected water concentration, was instead reached at higher concentration levels. The injection to recovery rate ratio might affect the chloride concentration breakthrough curve at the deep monitor well, which could explain this unexpected behavior. Because there are four high-permeability zones, if the rate of injection is smaller than the rate of recovery (natural artesian flow), the head differential might not be transmitted through the entire open wellbore, and injected water would probably flow only through the upper high- permeability zones. Therefore, observed chloride concentration values at the deep monitor well would be higher than the concentration of the injected water and would represent a mix of water from the different high-permeability zones. A generalized digital model was constructed to simulate the subsurface injection, storage, and recovery of freshwater in the Lower Floridan aquifer at the Lake Okeechobee injection-well site. The model was constructed using a modified version of the Saturated-Unsaturated TRAnsport code (SUTRA), which simulates variable-density advective-dispersive solute transport and variable-density ground-water flow. Satisfactory comparisons of simulated to observed dimensionless chloride concentrations for the deep monitor well were obtained when using the model during the injection and recovery phases of cycle 1, but not for the injection well during the recovery phase of cycle 1 even after several attempts. This precluded the determination of the recovery efficiency values by using the model. The unsatisfactory comparisons of simulated to observed dimensionless chloride concentrations for the injection well and failure of the model to represent the field data at this well could be due to the characteristics of the Lower Floridan aquifer (at the local scale), which is cavernous or conduit in nature. To test this possibility, Reynolds numbers were estimated at varying distances from the injection well, taking into consideration two aquifer types or conceptual systems, porous media and cavernous. For the porous media conceptual system, the Reynolds numbers were greater than 10 at distances less than 1.42 meters from the injection well. Thus, application of Darcy's law to ground-water flow might not be valid at this distance. However, at the deep monitor well (171 meters from the injection well), the Reynolds number was 0.08 which is indicative of laminar porous media flow. For the cavernous conceptual system, the Reynolds numbers were greater than 2,000 at distances less than 1,000 meters from the well. This number represents the upper limit of laminar flow, which is the fundamental assumption

  13. Development and Testing of the Europa Mission's Venturi Flow Meter

    NASA Technical Reports Server (NTRS)

    Diaz, C. E.; McKim, S. A.

    2017-01-01

    NASA's Marshall Space Flight Center (MSFC), in collaboration with NASA's Goddard Space Flight Center (GSFC), Fox Valve Development Corp. and Oxford Lasers, is developing a set of venturi flow meters for use on the Europa Mission's propulsion subsystem. The requirement for the venturi flow meters' throat diameters is approximately 0.040". An early risk reduction activity conducted by MSFC revealed that a venturi flow meter produced by FOX with a throat diameter near 0.040" had much higher pressure loss than venturi flow meters with larger throat diameters and venturis of similar throat diameter size but with no pressure taps (i.e. venturis with a throat length to diameter ratio of zero). In response, a series of venturi flow meters was fabricated and flow tested to gain insight into pressure recovery as it is affected by pressure port diameter, throat length and diffuser angle in an effort to improve the performance of a venturi flow meter. This presentation provides a summary of the venturi flow meter development activity including: a description of the test's objectives, a detailed description of each venturi configuration, a description of the manufacturing processes of the venturis, and observations from the test data. A summary of the current development activities will also be given, as well as the current development path forward. Ultimately, the knowledge gained through the fabrication and testing of these venturis provides guidance to design a flight venturi flow meters with pressure recoveries that is acceptable for the Europa flight application.

  14. Effect of Doppler flow meter position on discharge measurement in surcharged manholes.

    PubMed

    Yang, Haoming; Zhu, David Z; Liu, Yanchen

    2018-02-01

    Determining the proper installation location of flow meters is important for accurate measurement of discharge in sewer systems. In this study, flow field and flow regimes in two types of manholes under surcharged flow were investigated using a commercial computational fluid dynamics (CFD) code. The error in measuring the flow discharge using a Doppler flow meter (based on the velocity in a Doppler beam) was then estimated. The values of the corrective coefficient were obtained for the Doppler flow meter at different locations under various conditions. Suggestions for selecting installation positions are provided.

  15. 40 CFR 1065.230 - Raw exhaust flow meter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Raw exhaust flow meter. 1065.230... CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.230 Raw exhaust flow meter. (a) Application. You may use measured raw exhaust flow, as follows: (1) Use the actual...

  16. 40 CFR 1065.220 - Fuel flow meter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Fuel flow meter. 1065.220 Section 1065... ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.220 Fuel flow meter. (a) Application. You may use fuel flow in combination with a chemical balance of fuel, inlet air, and...

  17. 40 CFR 1065.220 - Fuel flow meter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Fuel flow meter. 1065.220 Section 1065... ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.220 Fuel flow meter. (a) Application. You may use fuel flow in combination with a chemical balance of fuel, inlet air, and...

  18. 27 CFR 19.1 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., section, or portion of this part: Accurate mass flow meter. A mass flow meter for making volume determinations of bulk distilled spirits. A mass flow meter used for tax determination of bulk spirits must be certified by the manufacturer of the meter or other qualified person as accurate within a tolerance of plus...

  19. 27 CFR 19.1 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., section, or portion of this part: Accurate mass flow meter. A mass flow meter for making volume determinations of bulk distilled spirits. A mass flow meter used for tax determination of bulk spirits must be certified by the manufacturer of the meter or other qualified person as accurate within a tolerance of plus...

  20. 27 CFR 19.1 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., section, or portion of this part: Accurate mass flow meter. A mass flow meter for making volume determinations of bulk distilled spirits. A mass flow meter used for tax determination of bulk spirits must be certified by the manufacturer of the meter or other qualified person as accurate within a tolerance of plus...

  1. 27 CFR 19.1 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., section, or portion of this part: Accurate mass flow meter. A mass flow meter for making volume determinations of bulk distilled spirits. A mass flow meter used for tax determination of bulk spirits must be certified by the manufacturer of the meter or other qualified person as accurate within a tolerance of plus...

  2. The Study on Flow Velocity Measurement of Antarctic Krill Trawl Model Experiment in North Bay of South China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Shuai; Wang, Lumin; Huang, Hongliang; Zhang, Xun

    2017-10-01

    From August 25 to 29, 2014, the project team carried out the experiment of Antarctic krill trawl in the Beihai Bay of the South China Sea. In order to understand the flow field of the network model in the course of the experiment, it is necessary to record the speed of the ship and to grasp the flow field of the ocean. Therefore, the ocean velocity is measured during the experiment. The flow rate in this experiment was measured using an acoustic Doppler flow meter (Vectoring Plus, Nortek, Norway). In order to compensate for the flow rate error caused by ship drift, the drift condition of the ship was also measured by the positioning device (Snapdragon MSM8274AB, Qualcomm, USA) used in the flow rate measurement. The results show that the actual velocity of the target sea area is in the range of 0.06-0.49 m / s and the direction is 216.17-351.70. And compared with the previous research, the influencing factors were analysed. This study proves that it is feasible to use point Doppler flow meter for velocity study in trawl model experiment.

  3. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers and...

  4. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers and...

  5. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers and...

  6. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers and...

  7. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers and...

  8. 40 CFR 98.426 - Data reporting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... measure CO2 concentration. (7) The location of the flow meter in your process chain in relation to the... through subsequent flow meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons...

  9. Tidally-driven Surface Flow in a Georgia Estuarine Saltmarsh

    NASA Astrophysics Data System (ADS)

    Young, D.; Bruder, B. L.; Haas, K. A.; Webster, D. R.

    2016-02-01

    Estuarine saltmarshes are diverse, valuable, and productive ecosystems. Vegetation dampens wave and current energy, thereby allowing the estuaries to serve as a nursery habitat for shellfish and fish species. Tidally-driven flow transports nutrients into and out of the estuary, nourishing inshore and offshore vegetation and animals. The effects of vegetation on the marsh hydrodynamics and on the estuary creek and channel flow are, unfortunately, poorly understood, and the knowledge that does exist primarily originates from modeling studies. Field studies addressing marsh surface flows are limited due to the difficulty of accurately measuring the water surface elevation and acquiring concurrent velocity measurements in the dense marsh vegetation. This study partially bridges the gap between the model observations of marsh flow driven by water surface elevation gradients and flume studies of flow through vegetation. Three current meters and three pressure transducers were deployed for three days along a transect perpendicular to the main channel (Little Ogeechee River) in a saltmarsh adjacent to Rose Dhu Island (Savannah, Georgia, USA). The pressure transducer locations were surveyed daily with static GPS yielding highly accurate water surface elevation data. During flood and ebb tide, water surface elevation differences between the marsh and Little Ogeechee River were observed up to 15 cm and pressure gradients were observed up to 0.0017 m of water surface elevation drop per m of linear distance. The resulting channel-to-saltmarsh pressure gradients substantially affected tidal currents at all current meters. At one current meter, the velocity was nearly perpendicular to the Little Ogeechee River bank. The velocity at this location was effectively modeled as a balance between the pressure gradient and marsh vegetation-induced drag force using the Darcy-Weisbach/Lindner's equations developed for flow-through-vegetation analysis in open channel flow.

  10. On-site flow calibration of turbine meters for natural gas custody transfer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ting, V.C.; Schexnayder, L.L.; Conkling, D.B.

    1991-05-01

    This paper presents the design criteria, performance characteristics, and calibration procedures relating to a turbine-meter flow-calibration facility used in the high-volume custody transfer of natural gas. The facility, located in Venice, LA, is owned and operated by Chevron U.S.A. Inc. and is used to meter sales volumes of up to 500 MMscf/D (14.16 {times} 10 std m{sup 3}/d) at a nominal operating pressure of 1,000 psig (6.9 MPa). The system includes three 12-in. (30.48 cm) turbine meters used for sales-volume measurement, a bank of sonic nozzles, and a master turbine meter connected in series with the sales meters. The sonicmore » nozzles and master meter serve as flow-proving and -calibration devices. sonic nozzles are recommended by the turbine-meter standard for meter calibration. This paper examines the performance of on-site calibration of gas turbine meters. The Venice facility successfully demonstrated that on-site calibration of gas-metering devices can ensure accurate gas-flow measurement under field conditions.« less

  11. Intelligent Flow Control Valve

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R (Inventor)

    2015-01-01

    The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

  12. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to.... We recommend that you use a diluted exhaust flow meter that meets the specifications in Table 1 of... verification in § 1065.307 and the calibration and verifications in § 1065.340 and § 1065.341. You may use the...

  13. Noninvasive blood-flow meter using a curved cannula with zero compensation for an axial flow blood pump.

    PubMed

    Kosaka, Ryo; Fukuda, Kyohei; Nishida, Masahiro; Maruyama, Osamu; Yamane, Takashi

    2013-01-01

    In order to monitor the condition of a patient using a left ventricular assist system (LVAS), blood flow should be measured. However, the reliable determination of blood-flow rate has not been established. The purpose of the present study is to develop a noninvasive blood-flow meter using a curved cannula with zero compensation for an axial flow blood pump. The flow meter uses the centrifugal force generated by the flow rate in the curved cannula. Two strain gauges served as sensors. The first gauges were attached to the curved area to measure static pressure and centrifugal force, and the second gauges were attached to straight area to measure static pressure. The flow rate was determined by the differences in output from the two gauges. The zero compensation was constructed based on the consideration that the flow rate could be estimated during the initial driving condition and the ventricular suction condition without using the flow meter. A mock circulation loop was constructed in order to evaluate the measurement performance of the developed flow meter with zero compensation. As a result, the zero compensation worked effectively for the initial calibration and the zero-drift of the measured flow rate. We confirmed that the developed flow meter using a curved cannula with zero compensation was able to accurately measure the flow rate continuously and noninvasively.

  14. 40 CFR 98.476 - Data reporting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... section. (a) If you receive CO2 by pipeline, report the following for each receiving flow meter: (1) The total net mass of CO2 received (metric tons) annually. (2) If a volumetric flow meter is used to receive CO2: (i) The volumetric flow through a receiving flow meter at standard conditions (in standard cubic...

  15. Cryogenic flow rate measurement with a laser Doppler velocimetry standard

    NASA Astrophysics Data System (ADS)

    Maury, R.; Strzelecki, A.; Auclercq, C.; Lehot, Y.; Loubat, S.; Chevalier, J.; Ben Rayana, F.

    2018-03-01

    A very promising alternative to the state-of-the-art static volume measurements for liquefied natural gas (LNG) custody transfer processes is the dynamic principle of flow metering. As the Designated Institute (DI) of the LNE (‘Laboratoire National de métrologie et d’Essais’, being the French National Metrology Institute) for high-pressure gas flow metering, Cesame-Exadebit is involved in various research and development programs. Within the framework of the first (2010-2013) and second (2014-2017) EURAMET Joint Research Project (JRP), named ‘Metrological support for LNG custody transfer and transport fuel applications’, Cesame-Exadebit explored a novel cryogenic flow metering technology using laser Doppler velocimetry (LDV) as an alternative to ultrasonic and Coriolis flow metering. Cesame-Exadebit is trying to develop this technique as a primary standard for cryogenic flow meters. Currently, cryogenic flow meters are calibrated at ambient temperatures with water. Results are then extrapolated to be in the Reynolds number range of real applications. The LDV standard offers a unique capability to perform online calibration of cryogenic flow meters in real conditions (temperature, pressure, piping and real flow disturbances). The primary reference has been tested on an industrial process in a LNG terminal during truck refuelling. The reference can calibrate Coriolis flow meters being used daily with all the real environmental constraints, and its utilisation is transparent for LNG terminal operators. The standard is traceable to Standard International units and the combined extended uncertainties have been determined and estimated to be lower than 0.6% (an ongoing improvement to reducing the correlation function uncertainty, which has a major impact in the uncertainty estimation).

  16. Balanced Flow Metering and Conditioning: Technology for Fluid Systems

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.

    2006-01-01

    Revolutionary new technology that creates balanced conditions across the face of a multi-hole orifice plate has been developed, patented and exclusively licensed for commercialization. This balanced flow technology simultaneously measures mass flow rate, volumetric flow rate, and fluid density with little or no straight pipe run requirements. Initially, the balanced plate was a drop in replacement for a traditional orifice plate, but testing revealed substantially better performance as compared to the orifice plate such as, 10 times better accuracy, 2 times faster (shorter distance) pressure recovery, 15 times less acoustic noise energy generation, and 2.5 times less permanent pressure loss. During 2004 testing at MSFC, testing revealed several configurations of the balanced flow meter that match the accuracy of Venturi meters while having only slightly more permanent pressure loss. However, the balanced meter only requires a 0.25 inch plate and has no upstream or downstream straight pipe requirements. As a fluid conditioning device, the fluid usually reaches fully developed flow within 1 pipe diameter of the balanced conditioning plate. This paper will describe the basic balanced flow metering technology, provide performance details generated by testing to date and provide implementation details along with calculations required for differing degrees of flow metering accuracy.

  17. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Gas meter or flow instrumentation... instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters or flow instrumentation to determine...

  18. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Gas meter or flow instrumentation... instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters or flow instrumentation to determine...

  19. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Gas meter or flow instrumentation... instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters or flow instrumentation to determine...

  20. 40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Gas meter or flow instrumentation... instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters or flow instrumentation to determine...

  1. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements... interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to... compression-ignition engines, 2-stroke spark-ignition engines, and 4-stroke spark-ignition engines below 19 kW...

  2. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements... interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to... compression-ignition engines, two-stroke spark-ignition engines, or four-stroke spark-ignition engines at or...

  3. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements... interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to... compression-ignition engines, 2-stroke spark-ignition engines, and 4-stroke spark-ignition engines below 19 kW...

  4. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements... interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to... compression-ignition engines, 2-stroke spark-ignition engines, and 4-stroke spark-ignition engines below 19 kW...

  5. Response of the Cardiovascular System to Vibration and Combined Stresses

    DTIC Science & Technology

    1980-11-01

    flow meter ( Zepeda Instruments) and our di- mension meter (Schussler and Associates) resulted in two suggestions: ’) an outline of possible steps to take...tionally, the flowmeter gate was not adjustable, further limiting our timing ability. Given the features of the Zepeda flowmeter in design (square-wave...dimension meter clock pulse (divided down) as the flow oscillator, rather than capturing the flow oscillator as was necessary with the Zepeda meter. This

  6. Instruments and Methods for Measuring the Flow of Water Around Ships and Ship Models

    DTIC Science & Technology

    1948-03-01

    velocity of flow, the direction of flow, and the speed of a ship are based on the pitot tube design- ed by Henri Pitot , a French physicist and engineer of...INTRODUCTION . .’ 1 DEVELOPMENT OP EARLY INSTRUMENTS . 2 PITOT -STATIC TUBE 2 SPEED LOOS k INSTRUMENT.- USED BY THE TAYLOR MODEL BASIN...5 CYLINDRICAL PITOT TUBE 5 SPHERICAL PITOT TUBE 10 ROTATING WAKE METER 1? BOW LOO 19 INSTRUMENTS USED BY OTHER MODEL BASINS 21

  7. Measuring Your Peak Flow Rate

    MedlinePlus

    ... Living with Asthma > Managing Asthma Measuring Your Peak Flow Rate Download Instructions A peak flow meter is ... to use. Who Benefits from Using a Peak Flow Meter? Many healthcare providers believe that people who ...

  8. Active bypass flow control for a seal in a gas turbine engine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ebert, Todd A.; Kimmel, Keith D.

    An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wearsmore » In at least one embodiment, the metering device may include an annular ring having at least one metering orifice extending therethrough, whereby alignment of the metering orifice with the outlet may be adjustable to change a cross-sectional area of an opening of aligned portions of the outlet and the metering orifice.« less

  9. A New Differential Pressure Flow Meter for Measurement of Human Breath Flow: Simulation and Experimental Investigation

    PubMed Central

    Bridgeman, Devon; Tsow, Francis; Xian, Xiaojun; Forzani, Erica

    2016-01-01

    The development and performance characterization of a new differential pressure-based flow meter for human breath measurements is presented in this article. The device, called a “Confined Pitot Tube,” is comprised of a pipe with an elliptically shaped expansion cavity located in the pipe center, and an elliptical disk inside the expansion cavity. The elliptical disk, named Pitot Tube, is exchangeable, and has different diameters, which are smaller than the diameter of the elliptical cavity. The gap between the disk and the cavity allows the flow of human breath to pass through. The disk causes an obstruction in the flow inside the pipe, but the elliptical cavity provides an expansion for the flow to circulate around the disk, decreasing the overall flow resistance. We characterize the new sensor flow experimentally and theoretically, using Comsol Multiphysics® software with laminar and turbulent models. We also validate the sensor, using inhalation and exhalation tests and a reference method. PMID:27818521

  10. Skin Friction Measurements Using Luminescent Oil Films

    NASA Astrophysics Data System (ADS)

    Husen, Nicholas M.

    As aircraft are designed to a greater extent on computers, the need for accurate and fast CFD algorithms has never been greater. The development of CFD algorithms requires experimental data against which CFD output can be validated and from which insight about flow physics can be acquired. Skin friction, in particular, is an important quantity to predict with CFD, and experimental skin friction data sets aid not only with the validation of the CFD predictions, but also in tuning the CFD models to predict specific flow fields. However, a practical experimental technique for collecting spatially and temporally resolved skin friction data on complex models does not yet exist. This dissertation develops and demonstrates a new luminescent oil film skin friction meter which can produce spatially-resolved quantitative steady and unsteady skin friction data on models with complex curvature. The skin friction acting on the surface of a thin film of oil can be approximated by the expression tauw =mu ouh/h, where mu o is the dynamic viscosity of the oil, uh is the velocity of the surface of the oil film, and h is the thickness of the oil film. The new skin friction meter determines skin friction by measuring h and uh. The oil film thickness h is determined by ratioing the intensity of the fluorescent emissions from the oil film with the intensity of the incident light which is scattered from the surface of the model. When properly calibrated, that ratio provides an absolute oil film thickness value. This oil film thickness meter is therefore referred as the Ratioed-Image Film-Thickness (RIFT) Meter. The oil film velocity uh is determined by monitoring the evolution of tagged molecules within the oil film: Photochromic molecules are dissolved into the fluorescent oil and a pattern is written into the oil film using an ultraviolet laser. The evolution of the pattern is recorded, and standard cross-correlation techniques are applied to the resulting sequence of images. This newly developed skin friction meter is therefore called the Luminescent Oil Film Flow-Tagging skin friction meter, or the LOFFT skin friction meter. The LOFFT skin friction meter is demonstrated by collecting time-averaged skin friction measurements on NASA's FAITH model and by collecting unsteady skin friction measurements with a frequency response of 600Hz. Higher frequency response is possible and is dependent on the experimental setup. This dissertation also contributes to the work done on the Global Luminescent Oil Film Skin Friction Meter (GLOFSFM) by noting that the technique could be influenced by ripples at the oil-air interface. An experiment studying the evolution of ripples at the oil-air interface was conducted to determine under what oil film conditions the GLOFSFM can be appropriately applied. The RIFT meter was crucial for this experiment, as it facilitated quantitative distributed oil film thickness measurements during the wind-tunnel run. The resulting data set is rich in content, permitting the computation of mean wavelengths, peak-to-trough ripple heights, wave speeds, and mean thicknesses. In addition to determining under what oil film conditions the GLOFSFM may be applied, this experiment directly determined the oil film conditions under which the velocity of the ripples may be used to proxy the velocity of the oil film surface. The RIFT meter and the ability to determine oil film surface velocity by monitoring ripple velocities admit yet another time-averaged skin friction meter, the Fluorescent-Oil Ripple-Velocity (FORV) skin friction meter. The FORV skin friction meter recovers skin friction as tau w = muovrip/H, where vrip is the velocity of the ripples, and H is the oil film thickness averaged over the thickness fluctuations due to the ripples. The FORV skin friction meter is demonstrated on NASA's FAITH model.

  11. Inadequate peak expiratory flow meter characteristics detected by a computerised explosive decompression device.

    PubMed

    Miller, M R; Atkins, P R; Pedersen, O F

    2003-05-01

    Recent evidence suggests that the frequency response requirements for peak expiratory flow (PEF) meters are higher than was first thought and that the American Thoracic Society (ATS) waveforms to test PEF meters may not be adequate for the purpose. The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters was tested by delivering two differently shaped flow-time profiles from a computer controlled explosive decompression device fitted with a fast response solenoid valve. These profiles matched population 5th and 95th centiles for rise time from 10% to 90% of PEF and dwell time of flow above 90% PEF. Profiles were delivered five times with identical chamber pressure and solenoid aperture at PEF. Any difference in recorded PEF for the two profiles indicates a poor dynamic response. The absolute (% of mean) flow differences in l/min for the V, MW, and PT PEF meters were 25 (4.7), 20 (3.9), and 2 (0.3), respectively, at PEF approximately 500 l/min, and 25 (10.5), 20 (8.7) and 6 (3.0) at approximately 200 l/min. For TZ and MS meters at approximately 500 l/min the differences were 228 (36.1) and 257 (39.2), respectively, and at approximately 200 l/min they were 51 (23.9) and 1 (0.5). All the meters met ATS accuracy requirements when tested with their waveforms. An improved method for testing the dynamic response of flow meters detects marked overshoot (underdamping) of TZ and MS responses not identified by the 26 ATS waveforms. This error could cause patient misclassification when using such meters with asthma guidelines.

  12. Numerical simulation of the effect of upstream swirling flow on swirl meter performance

    NASA Astrophysics Data System (ADS)

    Chen, Desheng; Cui, Baoling; Zhu, Zuchao

    2018-04-01

    Flow measurement is important in the fluid process and transmission system. For the need of accuracy measurement of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may produce swirling flow in the natural gas pipeline networks system and many other industry fields. In order to reveal the influence of upstream swirling flow on internal flow fields and the metrological characteristics, numerical simulations are carried out on the swirl meter. Using RNG k-ɛ turbulent model and SIMPLE algorithm, the flow field is numerically simulated under swirling flows generated from co-swirl and counter-swirl flow. Simulation results show fluctuation is enhanced or weakened depending on the rotating direction of swirling flow. A counter- swirl flow increases the entropy production rate at the inlet and outlet of the swirler, the junction region between throat and divergent section, and then the pressure loss is increased. The vortex precession dominates the static pressure distributions on the solid walls and in the channel, especially at the end region of the throat.

  13. Hydraulic characteristics of an underdrained irrigation circle, Muskegon County, wastewater disposal system, Michigan

    USGS Publications Warehouse

    McDonald, M.G.

    1981-01-01

    Muskegon County, Michigan, disposes of waste water by spray irrigating farmland on its waste-disposal site. Buried drains in the highly permeable unconfined aquifer at the site control the level of the water table. Hydraulic conductivity of the aquifer and drain-leakance, the reciprocal of resistance to flow into the drains, was determined at a representative irrigation circle while calibrating a model of the ground-water flow system. Hydraulic conductivity is 0.00055 meter per second in the north zone of the circle and 0.00039 meter per second in the south zone. Drain leakance is low in both zones: 2.9 x 10-6 meters per second in the north and 9.5 x 10-6 meters per second in the south. Low drain leakance is responsible for waterlogging when irrigation rates are maintained at design levels. The capacity of the study circle to accept waste water is 35 percent less than design capacity.

  14. Modeling of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand in Subsurface-Flow Constructed Treatment Wetlands

    DTIC Science & Technology

    2009-03-01

    meters. The input and output control structures are modeled as sharp crested , rectangular weirs one meter in width. The elevation of the input weir is...manipulated by adjusting the width of both the input and output weirs and the crest height of the output weir . All of these adjustments were found to be...reduction of the weir crest height had an effect on the amount of storm water retained during low precipitation conditions, but not on the crest

  15. 43 CFR 3275.16 - What standards apply to installing and maintaining meters?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...

  16. 43 CFR 3275.16 - What standards apply to installing and maintaining meters?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...

  17. 43 CFR 3275.16 - What standards apply to installing and maintaining meters?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...

  18. 43 CFR 3275.16 - What standards apply to installing and maintaining meters?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; (2) You must calibrate meters measuring steam or hot water flow with a turbine, vortex, ultrasonics... frequent; and (3) You must calibrate meters measuring steam or hot water flow with an orifice plate...

  19. 76 FR 4097 - Verdant Power, LLC (Verdant); Notice of Application Tendered for Filing With the Commission and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-24

    ... facilities would include: (1) Three 35-kilowatt (kW), 5-meter-diameter axial flow Kinetic System turbine...; (2) nine additional 5-meter-diameter axial flow Kinetic System turbine generator units mounted on...-meter-diameter axial flow Kinetic System turbine generator units mounted on six triframe mounts, with a...

  20. 40 CFR 98.476 - Data reporting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) of this section. (c) If you use more than one receiving flow meter, report the net total mass of CO2... section. (a) If you receive CO2 by pipeline, report the following for each receiving flow meter: (1) The total net mass of CO2 received (metric tons) annually. (2) If a volumetric flow meter is used to receive...

  1. 40 CFR 98.476 - Data reporting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) of this section. (c) If you use more than one receiving flow meter, report the net total mass of CO2... section. (a) If you receive CO2 by pipeline, report the following for each receiving flow meter: (1) The total net mass of CO2 received (metric tons) annually. (2) If a volumetric flow meter is used to receive...

  2. 40 CFR 1065.640 - Flow meter calibration calculations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... 1065.640 Section 1065.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.640 Flow meter...: Table 2 of § 1065.640—C fCFV versus β and γ for CFV Flow Meters C fCFV β γ exh =1.385 γ dexh = γ air = 1...

  3. 40 CFR 1065.640 - Flow meter calibration calculations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... 1065.640 Section 1065.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.640 Flow meter... Flow Meters C fCFV b g exh =1.385 g dexh = g air = 1.399 0.000 0.6822 0.6846 0.400 0.6857 0.6881 0.500...

  4. 40 CFR 1065.640 - Flow meter calibration calculations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... 1065.640 Section 1065.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.640 Flow meter...: Table 2 of § 1065.640—C fCFV versus β and γ for CFV Flow Meters C fCFV β γ exh =1.385 γ dexh = γ air = 1...

  5. 40 CFR 1065.640 - Flow meter calibration calculations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... 1065.640 Section 1065.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.640 Flow meter... Flow Meters C fCFV β γ exh =1.385 γ dexh = γ air = 1.399 0.000 0.6822 0.6846 0.400 0.6857 0.6881 0.500...

  6. 40 CFR 98.426 - Data reporting requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

  7. 40 CFR 98.426 - Data reporting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

  8. 40 CFR 98.426 - Data reporting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

  9. Structure and variability of the Western Maine Coastal Current

    USGS Publications Warehouse

    Churchill, J.H.; Pettigrew, N.R.; Signell, R.P.

    2005-01-01

    Analyses of CTD and moored current meter data from 1998 and 2000 reveal a number of mechanisms influencing the flow along the western coast of Maine. On occasions, the Eastern Maine Coastal Current extends into the western Gulf of Maine where it takes the form of a deep (order 100 m deep) and broad (order 20 km wide) southwestward flow with geostrophic velocities exceeding 20 cm s -1. This is not a coastally trapped flow, however. In fields of geostrophic velocity, computed from shipboard-CTD data, the core of this current is roughly centered at the 100 m isobath and its onshore edge is no closer than 10 km from the coast. Geostrophic velocity fields also reveal a relatively shallow (order 10 m deep) baroclinic flow adjacent to the coast. This flow is also directed to the southwest and appears to be principally comprised of local river discharge. Analyses of moored current meter data reveal wind-driven modulations of the coastal flow that are consistent with expectations from simple theoretical models. However, a large fraction of the near-shore current variance does not appear to be directly related to wind forcing. Sea-surface temperature imagery, combined with analysis of the moored current meter data, suggests that eddies and meanders within the coastal flow may at times dominate the near-shore current variance. ?? 2005 Elsevier Ltd. All rights reserved.

  10. Call-Center Based Disease Management of Pediatric Asthmatics

    DTIC Science & Technology

    2005-04-01

    study locations. Purchase peak flow meters. Prepare and reproduce patient education materials, and informed consent work sheets. Contract Oracle data...identified. Electronic peak flow meters have been purchased. Patient education materials and informed consent documents have been reproduced. A web-based...Research Center * Study population identified via military and Foundation Health databases * Electronic peak flow meters purchased * Patient education materials

  11. Comparison of current meters used for stream gaging

    USGS Publications Warehouse

    Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.

    1994-01-01

    The U.S. Geological Survey (USGS) is field and laboratory testing the performance of several current meters used throughout the world for stream gaging. Meters tested include horizontal-axis current meters from Germany, the United Kingdom, and the People's Republic of China, and vertical-axis and electromagnetic current meters from the United States. Summarized are laboratory test results for meter repeatability, linearity, and response to oblique flow angles and preliminary field testing results. All current meters tested were found to under- and over-register velocities; errors usually increased as the velocity and angle of the flow increased. Repeatability and linearity of all meters tested were good. In the field tests, horizontal-axis meters, except for the two meters from the People's Republic of China, registered higher velocity than did the vertical-axis meters.

  12. Measuring peak expiratory flow in general practice: comparison of mini Wright peak flow meter and turbine spirometer.

    PubMed Central

    Jones, K P; Mullee, M A

    1990-01-01

    OBJECTIVE--To compare measurements of the peak expiratory flow rate taken by the mini Wright peak flow meter and the turbine spirometer. DESIGN--Pragmatic study with randomised order of use of recording instruments. Phase 1 compared a peak expiratory flow type expiration recorded by the mini Wright peak flow meter with an expiration to forced vital capacity recorded by the turbine spirometer. Phase 2 compared peak expiratory flow type expirations recorded by both meters. Reproducibility was assessed separately. SETTING--Routine surgeries at Aldermoor Health Centre, Southampton. SUBJECTS--212 Patients aged 4 to 78 presenting with asthma or obstructive airways disease. Each patient contributed only once to each phase (105 in phase 1, 107 in phase 2), but some entered both phases on separate occasions. Reproducibility was tested on a further 31 patients. MAIN OUTCOME MEASURE--95% Limits of agreement between measurements on the two meters. RESULTS--208 (98%) Of the readings taken by the mini Wright meter were higher than the corresponding readings taken by the turbine spirometer, but the 95% limits of agreement (mean difference (2 SD] were wide (1 to 173 l/min). Differences due to errors in reproducibility were not sufficient to predict this level of disagreement. Analysis by age, sex, order of use, and the type of expiration did not detect any significant differences. CONCLUSIONS--The two methods of measuring peak expiratory flow rate were not comparable. The mini Wright meter is likely to remain the preferred instrument in general practice. PMID:2142611

  13. Non-invasive determination of instantaneous brachial blood flow using the oscillometric method.

    PubMed

    Liu, Shing-Hong; Wang, Jia-Jung; Cheng, Da-Chuan

    2009-08-01

    The oscillometric method has been widely used to measure arterial systolic and diastolic blood pressures, but its potential for arterial blood flow measurements still remains to be explored. The aim of this study was to non-invasively determine arterial blood flow using an oscillometric blood flow measurement system. The system consists of a pneumatic elastic cuff, an air-pumping motor, a releaser valve, a pressure transducer, and an airflow meter. To build a non-linear cuff model, we measured airflow pumped into the pneumatic cuff and cuff pressure using an airflow meter and pressure transducer during the inflation period, respectively. During the deflation period, only the pressure transducer was used to record cuff pressure. Based on the cuff model, the oscillometric blood flow waveform was obtained by integrating the oscillometric pressure waveform. We compared arterial blood flow derived from the maximum amplitude of the oscillometric blood flow waveform with Doppler-measured blood flow calculated with the diameters and blood velocities of the brachial arteries in 32 subjects who underwent diagnostic evaluations for peripheral arterial embolism. A linear correlation coefficient of r = 0.716 was found between the oscillometry- and Doppler-based blood flow measurements in the 32 subjects. These results suggest that blood flow passing through the brachial artery can be quantified non-invasively using the oscillometric approach after appropriate calibration.

  14. Ground-water flow near two radioactive-waste-disposal areas at the Western New York Nuclear Service Center, Cattaraugus County, New York; results of flow simulation

    USGS Publications Warehouse

    Bergeron, M.P.; Bugliosi, E.F.

    1988-01-01

    Two adjacent burial areas were excavated in a clay-rich till at a radioactive waste disposal site near West Valley in Cattaraugus County, N.Y.: (1) which contains mainly low-level radioactive wastes generated onsite by a nuclear fuel reprocessing plant, has been in operation since 1966; and (2) which contains commercial low-level radioactive wastes, was operated during 1963-75. Groundwater below the upper 3 meters of till generally moves downward through a 20- to 30-meter thick sequence of tills underlain by lacustrine and kame-delta deposits of fine sand and silt. Groundwater in the weathered, upper 3 meters of till can move laterally for several meters before either moving downward into the kame-delta deposits or discharging to the land surface. A two-dimensional finite-element model that simulates two vertical sections was used to evaluate hydrologic factors that control groundwater flow in the till. Conditions observed during March 1983 were reproduced accurately in steady-state simulations that used four isotropic units of differing hydraulic conductivity to represent two fractured and weathered till units near land surfaces, an intermediate group of isolated till zones that contain significant amounts of fine sand and silt, and a sequence of till units at depths that have been consolidated by overburden pressure. Recharge rates used in the best-fit simulation ranged from 1.4 cm/yr along smooth, sloping or compacted surfaces to 3.8 cm/yr near swampy areas. Values of hydraulic conductivity and infiltration used in the calibrated best-fit model were nearly identical to values used in a previous model analysis of the nearby commercial-waste burial area. Results of the model simulations of a burial pit assumed to be filled with water indicate that water near the bottom of the burial pit would migrate laterally in the shallow, weathered till for 5 to 6 meters before moving downward into the unweathered till, and water near the top of the pit would move laterally less than 20 meters before moving downward into the unweathered till. These results indicate that subsurface migration of radionuclides in groundwater to points of discharge to land surface is unlikely as long as the water level does not rise into the reworked cover material. (Author 's abstract)

  15. Peak flowmeter resistance decreases peak expiratory flow in subjects with COPD.

    PubMed

    Miller, M R; Pedersen, O F

    2000-07-01

    Previous studies have shown that the added resistance of a mini-Wright peak expiratory flow (PEF) meter reduced PEF by approximately 8% in normal subjects because of gas compression reducing thoracic gas volume at PEF and thus driving elastic recoil pressure. We undertook a body plethysmographic study in 15 patients with chronic obstructive pulmonary disease (COPD), age 65.9 +/- 6.3 yr (mean +/- SD, range 53-75 yr), to examine whether their recorded PEF was also limited by the added resistance of a PEF meter. The PEF meter increased alveolar pressure at PEF (Ppeak) from 3.7 +/- 1.4 to 4.7 +/- 1.5 kPa (P = 0.01), and PEF was reduced from 3.6 +/- 1.3 l/s to 3.2 +/- 0.9 l/s (P = 0.01). The influence of flow limitation on PEF and Ppeak was evaluated by a simple four-parameter model based on the wave-speed concept. We conclude that added external resistance in patients with COPD reduced PEF by the same mechanisms as in healthy subjects. Furthermore, the much lower Ppeak in COPD patients is a consequence of more severe flow limitation than in healthy subjects and not of deficient muscle strength.

  16. Primary flow meter for calibrating a sniffer test leak artefact by a pressure rise method

    NASA Astrophysics Data System (ADS)

    Arai, Kenta; Yoshida, Hajime

    2014-10-01

    Sniffer tests are used to locate leaks in equipment during operation. The sensitivity of a sniffer leak detector must be calibrated against a known gas flow to atmospheric pressure generated by a sniffer test leak artefact. We have developed a primary flow meter for calibrating gas flows to atmospheric pressure through the leak artefact. The flow meter is based on a pressure rise method and two chambers are used to measure the pressure rise with small uncertainty even at atmospheric pressure. The calibration range of the flow rate is 5 × 10-7 Pa m3 s-1 to 7 × 10-4 Pa m3 s-1 to atmospheric pressure at 23.0 °C with a minimum uncertainty of 1.4% (k = 2), as well as 4 × 10-8 Pa m3 s-1 to 5 × 10-4 Pa m3 s-1 to a vacuum at 23.0 °C. The long term stability of the flow meter was determined as 0.41% by repeated measurements of the conductance of the leak artefact. In case of the flow rate into a vacuum, the flow meter was successfully linked to the international reference value of CCM.P-K12 by a lab-internal comparison.

  17. Experimental investigation of forebody and wing leading-edge vortex interactions at high angles of attack

    NASA Technical Reports Server (NTRS)

    Erickson, G. E.; Gilbert, W. P.

    1983-01-01

    An experimental investigation was conducted to assess the vortex flow-field interactions on an advanced, twin-jet fighter aircraft configuration at high angles of attack. Flow-field surveys were conducted on a small-scale model in the Northrop 0.41 - by 0.60-meter water tunnel and, where appropriate, the qualitative observations were correlated with low-speed wind tunnel data trends obtained on a large-scale model of the advanced fighter in the NASA Langley Research Center 30- by 60-foot (9.1- by 18.3-meter) facility. Emphasis was placed on understanding the interactions of the forebody and LEX-wing vortical flows, defining the effects on rolling moment variation with sideslip, and identifying modifications to control or regulate the vortex interactions at high angles of attack. The water tunnel flow visualization results and wind tunnel data trend analysis revealed the potential for strong interactions between the forebody and LEX vortices at high angles of attack. In particular, the forebody flow development near the nose could be controlled by means of carefully-positioned radome strakes. The resultant strake-induced flow-field changes were amplified downstream by the more powerful LEX vortical motions with subsequent large effects on wing flow separation characteristics.

  18. Direct measurement of proximal isovelocity surface area by real-time three-dimensional color Doppler for quantitation of aortic regurgitant volume: an in vitro validation.

    PubMed

    Pirat, Bahar; Little, Stephen H; Igo, Stephen R; McCulloch, Marti; Nosé, Yukihiko; Hartley, Craig J; Zoghbi, William A

    2009-03-01

    The proximal isovelocity surface area (PISA) method is useful in the quantitation of aortic regurgitation (AR). We hypothesized that actual measurement of PISA provided with real-time 3-dimensional (3D) color Doppler yields more accurate regurgitant volumes than those estimated by 2-dimensional (2D) color Doppler PISA. We developed a pulsatile flow model for AR with an imaging chamber in which interchangeable regurgitant orifices with defined shapes and areas were incorporated. An ultrasonic flow meter was used to calculate the reference regurgitant volumes. A total of 29 different flow conditions for 5 orifices with different shapes were tested at a rate of 72 beats/min. 2D PISA was calculated as 2pi r(2), and 3D PISA was measured from 8 equidistant radial planes of the 3D PISA. Regurgitant volume was derived as PISA x aliasing velocity x time velocity integral of AR/peak AR velocity. Regurgitant volumes by flow meter ranged between 12.6 and 30.6 mL/beat (mean 21.4 +/- 5.5 mL/beat). Regurgitant volumes estimated by 2D PISA correlated well with volumes measured by flow meter (r = 0.69); however, a significant underestimation was observed (y = 0.5x + 0.6). Correlation with flow meter volumes was stronger for 3D PISA-derived regurgitant volumes (r = 0.83); significantly less underestimation of regurgitant volumes was seen, with a regression line close to identity (y = 0.9x + 3.9). Direct measurement of PISA is feasible, without geometric assumptions, using real-time 3D color Doppler. Calculation of aortic regurgitant volumes with 3D color Doppler using this methodology is more accurate than conventional 2D method with hemispheric PISA assumption.

  19. Turbulent Swirling Flow Downstream of an Abrupt Pipe Expansion -- Modeling and Experimental Measurements.

    DTIC Science & Technology

    1982-07-01

    aerospace engineering um~Ŕ" eqe~vswse 0engiee amp snry stem englnerlag. enI~e so ISaCW , meterI scienc Turbulent Swirling Flow Dowstreas of an Abrupt...With the horizontal test section and circumferentially local measurements, the extent of the influence of gravity -induced convection can be determined

  20. In Situ Steam Fracture Experiments.

    DTIC Science & Technology

    1984-12-31

    pressure and tempera- ture data for use in validation of multi-phase flow models describing - condensation/vaporization, heat-transfer, and fluid/vapor...provide an excellent base for development and/or verification of steam-fracture models for low- permeability materials where heat transfer is significant...representative of post-shot cavity conditions. Steam flow tests have been performed at S-CUBED in a 3-meter long by 20-centimeter diameter sand column. In

  1. Evaluation of the apparent losses caused by water meter under-registration in intermittent water supply.

    PubMed

    Criminisi, A; Fontanazza, C M; Freni, G; Loggia, G La

    2009-01-01

    Apparent losses are usually caused by water theft, billing errors, or revenue meter under-registration. While the first two causes are directly related to water utility management and may be reduced by improving company procedures, water meter inaccuracies are considered to be the most significant and hardest to quantify. Water meter errors are amplified in networks subjected to water scarcity, where users adopt private storage tanks to cope with the intermittent water supply. The aim of this paper is to analyse the role of two variables influencing the apparent losses: water meter age and the private storage tank effect on meter performance. The study was carried out in Palermo (Italy). The impact of water meter ageing was evaluated in laboratory by testing 180 revenue meters, ranging from 0 to 45 years in age. The effects of the private water tanks were determined via field monitoring of real users and a mathematical model. This study demonstrates that the impact on apparent losses from the meter starting flow rapidly increases with meter age. Private water tanks, usually fed by a float valve, overstate meter under-registration, producing additional apparent losses between 15% and 40% for the users analysed in this study.

  2. Flow-Signature Analysis of Water Consumption in Nonresidential Building Water Networks Using High-Resolution and Medium-Resolution Smart Meter Data: Two Case Studies

    NASA Astrophysics Data System (ADS)

    Clifford, Eoghan; Mulligan, Sean; Comer, Joanne; Hannon, Louise

    2018-01-01

    Real-time monitoring of water consumption activities can be an effective mechanism to achieve efficient water network management. This approach, largely enabled by the advent of smart metering technologies, is gradually being practiced in domestic and industrial contexts. In particular, identifying water consumption habits from flow-signatures, i.e., the specific end-usage patterns, is being investigated as a means for conservation in both the residential and nonresidential context. However, the quality of meter data is bivariate (dependent on number of meters and data temporal resolution) and as a result, planning a smart metering scheme is relatively difficult with no generic design approach available. In this study, a comprehensive medium-resolution to high-resolution smart metering program was implemented at two nonresidential trial sites to evaluate the effect of spatial and temporal data aggregation. It was found that medium-resolution water meter data were capable of exposing regular, continuous, peak use, and diurnal patterns which reflect group wide end-usage characteristics. The high-resolution meter data permitted flow-signature at a personal end-use level. Through this unique opportunity to observe water usage characteristics via flow-signature patterns, newly defined hydraulic-based design coefficients determined from Poisson rectangular pulse were developed to intuitively aid in the process of pattern discovery with implications for automated activity recognition applications. A smart meter classification and siting index was introduced which categorizes meter resolution in terms of their suitable application.

  3. 40 CFR 63.11646 - What are my compliance requirements?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... with Method 29 must collect a minimum sample volume of 0.85 dry standard cubic meters (30 dry standard... weight measurement device, mass flow meter, or densitometer and volumetric flow meter to measure ore...) Measure the weight of concentrate (produced by electrowinning, Merrill Crowe process, gravity feed, or...

  4. 40 CFR 63.11646 - What are my compliance requirements?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... with Method 29 must collect a minimum sample volume of 0.85 dry standard cubic meters (30 dry standard... weight measurement device, mass flow meter, or densitometer and volumetric flow meter to measure ore...) Measure the weight of concentrate (produced by electrowinning, Merrill Crowe process, gravity feed, or...

  5. 40 CFR 63.11646 - What are my compliance requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with Method 29 must collect a minimum sample volume of 0.85 dry standard cubic meters (30 dry standard... weight measurement device, mass flow meter, or densitometer and volumetric flow meter to measure ore...) Measure the weight of concentrate (produced by electrowinning, Merrill Crowe process, gravity feed, or...

  6. 40 CFR 63.11646 - What are my compliance requirements?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... with Method 29 must collect a minimum sample volume of 0.85 dry standard cubic meters (30 dry standard... weight measurement device, mass flow meter, or densitometer and volumetric flow meter to measure ore...) Measure the weight of concentrate (produced by electrowinning, Merrill Crowe process, gravity feed, or...

  7. The effects of sampling location and turbulence on discharge estimates in short converging turbine intakes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Romero-Gomez, P.; Harding, S. F.; Richmond, M. C.

    2017-01-01

    Standards provide recommendations for best practices when installing current meters to measure fluid flow in closed conduits. A central guideline requires the velocity distribution to be regular and the flow steady. Because of the nature of the short converging intakes typical of low-head hydroturbines, these assumptions may be invalid if current meters are intended to be used to estimate discharge. Usual concerns are (1) the effects of the number of devices, (2) the sampling location and (3) the high turbulence caused by blockage from submersible traveling screens usually deployed for safe downstream fish passage. These three effects were examined inmore » the present study by using 3D simulated flow fields in both steady-state and transient modes. In the process of describing an application at an existing hydroturbine intake at Ice Harbor Dam, the present work outlined the methods involved, which combined computational fluid dynamics, laboratory measurements in physical models of the hydroturbine, and current meter performance evaluations in experimental settings. The main conclusions in this specific application were that a steady-state flow field sufficed to determine the adequate number of meters and their location, and that both the transverse velocity and turbulence intensity had a small impact on estimate errors. However, while it may not be possible to extrapolate these findings to other field conditions and measuring devices, the study laid out a path to conduct similar assessments in other applications.« less

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harding, Samuel F.; Romero-Gomez, Pedro D. J.; Richmond, Marshall C.

    Standards provide recommendations for the best practices in the installation of current meters for measuring fluid flow in closed conduits. These include PTC-18 and IEC-41 . Both of these standards refer to the requirements of the ISO Standard 3354 for cases where the velocity distribution is assumed to be regular and the flow steady. Due to the nature of the short converging intakes of Kaplan hydroturbines, these assumptions may be invalid if current meters are intended to be used to characterize turbine flows. In this study, we examine a combination of measurement guidelines from both ISO standards by means ofmore » virtual current meters (VCM) set up over a simulated hydroturbine flow field. To this purpose, a computational fluid dynamics (CFD) model was developed to model the velocity field of a short converging intake of the Ice Harbor Dam on the Snake River, in the State of Washington. The detailed geometry and resulting wake of the submersible traveling screen (STS) at the first gate slot was of particular interest in the development of the CFD model using a detached eddy simulation (DES) turbulence solution. An array of virtual point velocity measurements were extracted from the resulting velocity field to simulate VCM at two virtual measurement (VM) locations at different distances downstream of the STS. The discharge through each bay was calculated from the VM using the graphical integration solution to the velocity-area method. This method of representing practical velocimetry techniques in a numerical flow field has been successfully used in a range of marine and conventional hydropower applications. A sensitivity analysis was performed to observe the effect of the VCM array resolution on the discharge error. The downstream VM section required 11–33% less VCM in the array than the upstream VM location to achieve a given discharge error. In general, more instruments were required to quantify the discharge at high levels of accuracy when the STS was introduced because of the increased spatial variability of the flow velocity.« less

  9. State-of-charge coulometer

    NASA Technical Reports Server (NTRS)

    Rowlette, J. J. (Inventor)

    1985-01-01

    A coulometer for accurately measuring the state-of-charge of an open-cell battery utilizing an aqueous electrolyte, includes a current meter for measuring the battery/discharge current and a flow meter for measuring the rate at which the battery produces gas during charge and discharge. Coupled to the flow meter is gas analyzer which measures the oxygen fraction of the battery gas. The outputs of the current meter, flow meter, and gas analyzer are coupled to a programmed microcomputer which includes a CPU and program and data memories. The microcomputer calculates that fraction of charge and discharge current consumed in the generation of gas so that the actual state-of-charge can be determined. The state-of-charge is then shown on a visual display.

  10. BAT3 Analyzer: Real-Time Data Display and Interpretation Software for the Multifunction Bedrock-Aquifer Transportable Testing Tool (BAT3)

    USGS Publications Warehouse

    Winston, Richard B.; Shapiro, Allen M.

    2007-01-01

    The BAT3 Analyzer provides real-time display and interpretation of fluid pressure responses and flow rates measured during geochemical sampling, hydraulic testing, or tracer testing conducted with the Multifunction Bedrock-Aquifer Transportable Testing Tool (BAT3) (Shapiro, 2007). Real-time display of the data collected with the Multifunction BAT3 allows the user to ensure that the downhole apparatus is operating properly, and that test procedures can be modified to correct for unanticipated hydraulic responses during testing. The BAT3 Analyzer can apply calibrations to the pressure transducer and flow meter data to display physically meaningful values. Plots of the time-varying data can be formatted for a specified time interval, and either saved to files, or printed. Libraries of calibrations for the pressure transducers and flow meters can be created, updated and reloaded to facilitate the rapid set up of the software to display data collected during testing with the Multifunction BAT3. The BAT3 Analyzer also has the functionality to estimate calibrations for pressure transducers and flow meters using data collected with the Multifunction BAT3 in conjunction with corroborating check measurements. During testing with the Multifunction BAT3, and also after testing has been completed, hydraulic properties of the test interval can be estimated by comparing fluid pressure responses with model results; a variety of hydrogeologic conceptual models of the formation are available for interpreting fluid-withdrawal, fluid-injection, and slug tests.

  11. Simulation of hydrodynamics, temperature, and dissolved oxygen in Table Rock Lake, Missouri, 1996-1997

    USGS Publications Warehouse

    Green, W. Reed; Galloway, Joel M.; Richards, Joseph M.; Wesolowski, Edwin A.

    2003-01-01

    Outflow from Table Rock Lake and other White River reservoirs support a cold-water trout fishery of substantial economic yield in south-central Missouri and north-central Arkansas. The Missouri Department of Conservation has requested an increase in existing minimum flows through the Table Rock Lake Dam from the U.S. Army Corps of Engineers to increase the quality of fishable waters downstream in Lake Taneycomo. Information is needed to assess the effect of increased minimum flows on temperature and dissolved- oxygen concentrations of reservoir water and the outflow. A two-dimensional, laterally averaged, hydrodynamic, temperature, and dissolved-oxygen model, CE-QUAL-W2, was developed and calibrated for Table Rock Lake, located in Missouri, north of the Arkansas-Missouri State line. The model simulates water-surface elevation, heat transport, and dissolved-oxygen dynamics. The model was developed to assess the effects of proposed increases in minimum flow from about 4.4 cubic meters per second (the existing minimum flow) to 11.3 cubic meters per second (the increased minimum flow). Simulations included assessing the effect of (1) increased minimum flows and (2) increased minimum flows with increased water-surface elevations in Table Rock Lake, on outflow temperatures and dissolved-oxygen concentrations. In both minimum flow scenarios, water temperature appeared to stay the same or increase slightly (less than 0.37 ?C) and dissolved oxygen appeared to decrease slightly (less than 0.78 mg/L) in the outflow during the thermal stratification season. However, differences between the minimum flow scenarios for water temperature and dissolved- oxygen concentration and the calibrated model were similar to the differences between measured and simulated water-column profile values.

  12. Semi-Numerical Studies of the Three-Meter Spherical Couette Experiment Utilizing Data Assimilation

    NASA Astrophysics Data System (ADS)

    Burnett, S. C.; Rojas, R.; Perevalov, A.; Lathrop, D. P.

    2017-12-01

    The model of the Earth's magnetic field has been investigated in recent years through experiments and numerical models. At the University of Maryland, experimental studies are implemented in a three-meter spherical Couette device filled with liquid sodium. The inner and outer spheres of this apparatus mimic the planet's inner core and core-mantle boundary, respectively. These experiments incorporate high velocity flows with Reynolds numbers 108. In spherical Couette geometry, the numerical scheme applied to this work features finite difference methods in the radial direction and pseudospectral spherical harmonic transforms elsewhere [Schaeffer, N. G3 (2013)]. Adding to the numerical model, data assimilation integrates the experimental outer-layer magnetic field measurements. This semi-numerical model can then be compared to the experimental results as well as forecasting magnetic field changes. Data assimilation makes it possible to get estimates of internal motions of the three-meter experiment that would otherwise be intrusive or impossible to obtain in experiments or too computationally expensive with a purely numerical code. If we can provide accurate models of the three-meter device, it is possible to attempt to model the geomagnetic field. We gratefully acknowledge the support of NSF Grant No. EAR1417148 & DGE1322106.

  13. Semi-Numerical Studies of the Three-Meter Spherical Couette Experiment Utilizing Data Assimilation

    NASA Astrophysics Data System (ADS)

    Burnett, Sarah; Rojas, Ruben; Perevalov, Artur; Lathrop, Daniel; Ide, Kayo; Schaeffer, Nathanael

    2017-11-01

    The model of the Earth's magnetic field has been investigated in recent years through experiments and numerical models. At the University of Maryland, experimental studies are implemented in a three-meter spherical Couette device filled with liquid sodium. The inner and outer spheres of this apparatus mimic the planet's inner core and core-mantle boundary, respectively. These experiments incorporate high velocity flows with Reynolds numbers 108 . In spherical Couette geometry, the numerical scheme applied to this work features finite difference methods in the radial direction and pseudospectral spherical harmonic transforms elsewhere. Adding to the numerical model, data assimilation integrates the experimental outer-layer magnetic field measurements. This semi-numerical model can then be compared to the experimental results as well as forecasting magnetic field changes. Data assimilation makes it possible to get estimates of internal motions of the three-meter experiment that would otherwise be intrusive or impossible to obtain in experiments or too computationally expensive with a purely numerical code. If we can provide accurate models of the three-meter device, it is possible to attempt to model the geomagnetic field. We gratefully acknowledge the support of NSF Grant No. EAR1417148 & DGE1322106.

  14. Vapor-screen flow-visualization experiments in the NASA Langley 0.3-m transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Selby, G. V.

    1986-01-01

    The vortical flow on the leeward side of a delta-wing model has been visualized at several different tunnel conditions in the NASA Langley 0.3-Meter Transonic Cryogenic Tunnel using a vapor-screen flow-visualization technique. Vapor-screen photographs of the subject flow field are presented and interpreted relative to phenomenological implications. Results indicate that the use of nitrogen fog in conjunction with the vapor-screen technique is feasibile.

  15. Quantifying exchange between groundwater and surface water in rarely measured organic sediments

    NASA Astrophysics Data System (ADS)

    Rosenberry, D. O.; Cavas, M.; Keith, D.; Gefell, M. J.; Jones, P. M.

    2016-12-01

    Transfer of water and chemicals between poorly competent organic sediments and surface water in low-energy riverine and lentic settings depends on several factors, including rate and direction of flow, redox state, number and type of benthic invertebrates, and chemical gradients at and near the sediment-water interface. In spite of their commonly large areal extent, direct measurements of flow in soft, organic sediments are rarely made and little is known about flux direction, rate, or heterogeneity. Commonly used monitoring wells are difficult to install and suffer from slow response to changing hydraulic head due to the low permeability of these sediments. Seepage meters can directly quantify seepage flux if several challenges can be overcome. Meters are difficult to install and operate where water is deep, visibility is poor, and the position of the sediment-water interface is not readily apparent. Soft, easily eroded sediment can be displaced during meter installation, creating bypass flow beneath the bottom of the seepage cylinder. Poorly competent sediments often cannot support the weight of the meters; they slowly sink into the bed and displace water inside the seepage cylinder, which leads to the interpretation of large upward flow. Decaying organic material within the sediment generates gas that can displace water and corrupt seepage-meter measurements. Several inexpensive modifications to a standard seepage meter, as well as precautions during installation and operation, can minimize these sources of error. Underwater video cameras can be mounted to the meter to remotely observe sediment disturbance during sensor installation and monitor the stability of the meter insertion depth during the period of deployment. Anchor rods can be driven a meter or more into the sediment until refusal, firmly anchoring the seepage meter at a constant sediment insertion depth. Data collected from modified seepage meters installed in Minnesota and New York demonstrate the importance of quantifying flows in these challenging settings where biogeochemistry is complex and seepage rates commonly have been assumed to be insignificantly small.

  16. Discharge Measurements in Shallow Urban Streams Using a Hydroacoustic Current Meter

    USGS Publications Warehouse

    Fisher, G.T.; Morlock, S.E.; ,

    2002-01-01

    Hydroacoustic current-meter measurements were evaluated in small urban streams under a range of stages, velocities, and channel-bottom materials. Because flow in urban streams is often shallow, conventional mechanical current-meter measurements are difficult or impossible to make. The rotating-cup Price pygmy meter that is widely used by the U.S. Geological Survey and other agencies should not be used in depths below 0.20 ft and velocities less than 0.30 ft/s. The hydroacoustic device provides measurements at depths as shallow as 0.10 ft and velocities as low as 0.10 ft/s or less. Measurements using the hydroacoustic current meter were compared to conventional discharge measurements. Comparisons with Price-meter measurements were favorable within the range of flows for which the meters are rated. Based on laboratory and field tests, velocity measurements with the hydroacoustic cannot be validated below about 0.07 ft/s. However, the hydroacoustic meter provides valuable information on direction and magnitude of flow even at lower velocities, which otherwise could not be measured with conventional measurements.

  17. Advection within shallow pore waters of a coastal lagoon, Florida

    USGS Publications Warehouse

    Cable, J.E.; Martin, Jonathan B.; Swarzenski, Peter W.; Lindenberg, Mary K.; Steward, Joel

    2004-01-01

    Ground water sources can be a significant portion of a local water budget in estuarine environments, particularly in areas with high recharge rates, transmissive aquifers, and permeable marine sediments. However, field measurements of ground water discharge are often incongruent with ground water flow modeling results, leaving many scientists unsure which estimates are accurate. In this study, we find that both measurements and model results are reasonable. The difference between estimates apparently results from the sources of water being measured and not the techniques themselves. In two locations in the Indian River Lagoon estuarine system, we found seepage meter rates similar to rates calculated from the geochemical tracers 222Rn and 226Ra. Ground water discharge rates ranged from 4 to 9 cm/d using seepage meters and 3 to 20 cm/d using 222Rn and 226Ra. In contrast, in comparisons to other studies where finite element ground water flow modeling was used, much lower ground water discharge rates of ∼0.05 to 0.15 cm/d were estimated. These low rates probably represent discharge of meteoric ground water from land-recharged aquifers, while the much higher rates measured with seepage meters, 222Rn, and 226Ra likely include an additional source of surface waters that regularly flush shallow (< 1 m depth) sediments. This resultant total flow of mixed land-recharged water and recirculated surface waters contributes to the total biogeochemical loading in this shallow estuarine environment.

  18. A High Resolution, Integrated Approach to Modeling Climate Change Impacts to a Mountain Headwaters Catchment using ParFlow

    NASA Astrophysics Data System (ADS)

    Pribulick, C. E.; Maxwell, R. M.; Williams, K. H.; Carroll, R. W. H.

    2014-12-01

    Prediction of environmental response to global climate change is paramount for regions that rely upon snowpack for their dominant water supply. Temperature increases are anticipated to be greater at higher elevations perturbing hydrologic systems that provide water to millions of downstream users. In this study, the relationships between large-scale climatic change and the corresponding small-scale hydrologic processes of mountainous terrain are investigated in the East River headwaters catchment near Gothic, CO. This catchment is emblematic of many others within the upper Colorado River Basin and covers an area of 250 square kilometers, has a topographic relief of 1420 meters, an average elevation of 3266 meters and has varying stream characteristics. This site allows for the examination of the varying effect of climate-induced changes on the hydrologic response of three different characteristic components of the catchment: a steep high-energy mountain system, a medium-grade lower-energy system and a low-grade low-energy meandering floodplain. To capture the surface and subsurface heterogeneity of this headwaters system the basin has been modeled at a 10-meter resolution using ParFlow, a parallel, integrated hydrologic model. Driven by meteorological forcing, ParFlow is able to capture land surface processes and represents surface and subsurface interactions through saturated and variably saturated heterogeneous flow. Data from Digital Elevation Models (DEMs), land cover, permeability, geologic and soil maps, and on-site meteorological stations, were prepared, analyzed and input into ParFlow as layers with a grid size comprised of 1403 by 1685 cells to best represent the small-scale, high resolution model domain. Water table depth, soil moisture, soil temperature, snowpack, runoff and local energy budget values provide useful insight into the catchments response to the Intergovernmental Panel on Climate Change (IPCC) temperature projections. In the near term, coupling this watershed model with one describing a diverse suite of subsurface elemental cycling pathways, including carbon and nitrogen, will provide an improved understanding of the response of the subsurface ecosystems to hydrologic transitions induced as a result of global climate change.

  19. Evaluation and enhancement of Texas ramp metering strategies, compliance, and alternative enforcement techniques: Go with the flow Houston. Public outreach plan (revised); Interim research report, September 1995--October 1996

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lancaster, S.; Fette, B.; Busler, L.

    This report describes the public outreach plan on the implementation of ramp meters along the Katy Freeway in Houston, Generally, ramp metering is neither beloved nor understood by the public. To gain public awareness, acceptance, compliance and continued support, ramp metering operations should be reinforced by a strong, ongoing public information and outreach campaign that communicates the need for and benefits of the program. Because the term `ramp metering` exhibits restrictions on the public, the phrase `Flow Signals` was developed to better describe the benefits of ramp metering; enhanced flow of traffic, fewer bottlenecks, and fewer trip delays. The logo,more » `Go with the Flow Houston,` and a graphic identity were developed to help communicate the theme throughout the various media where both the primary and secondary messages are intended to reach 15 different audiences. These media will include: a PSA, both static and changeable message signs, a brochure, Internet web site information, letters to specific audience and media relations efforts.« less

  20. Methods of measuring pumpage through closed-conduit irrigation systems

    USGS Publications Warehouse

    Kjelstrom, L.C.

    1991-01-01

    Methods of measuring volumes of water withdrawn from the Snake River and its tributaries and pumped through closed-conduit irrigation systems were needed for equitable management of and resolution of conflicts over water use. On the basis of evaluations and field tests by researchers from the University of Idaho, Water Resources Research Institute, Moscow, Idaho, an impeller meter was selected to monitor pumpage through closed-conduit systems. In 1988, impeller meters were installed at 20 pumping stations along the Snake River between the Upper Salmon Falls and C.J. Strike Dams. Impeller-derived pumpage data were adjusted if they differed substantially from ultrasonic flow-meter- or current-meter-derived values. Comparisons of pumpage data obtained by ultrasonic flow-meter and current-meter measurements indicated that the ultrasonic flow meter was a reliable means to check operation of impeller meters. The equipment generally performed satisfactorily, and reliable pumpage data could be obtained using impeller meters in closed-conduit irrigation systems. Many pumping stations that divert water from the Snake River for irrigation remain unmeasured; however, regression analyses indicate that total pumpage can be reasonably estimated on the basis of electrical power consumption data, an approximation of total head at a pumping station, and a derived coefficient.

  1. Immersed transient eddy current flow metering: a calibration-free velocity measurement technique for liquid metals

    NASA Astrophysics Data System (ADS)

    Krauter, N.; Stefani, F.

    2017-10-01

    Eddy current flow meters are widely used for measuring the flow velocity of electrically conducting fluids. Since the flow induced perturbations of a magnetic field depend both on the geometry and the conductivity of the fluid, extensive calibration is needed to get accurate results. Transient eddy current flow metering has been developed to overcome this problem. It relies on tracking the position of an impressed eddy current system that is moving with the same velocity as the conductive fluid. We present an immersed version of this measurement technique and demonstrate its viability by numerical simulations and a first experimental validation.

  2. Elbow mass flow meter

    DOEpatents

    McFarland, Andrew R.; Rodgers, John C.; Ortiz, Carlos A.; Nelson, David C.

    1994-01-01

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  3. 40 CFR 98.443 - Calculating CO2 geologic sequestration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... each gas-liquid separator for which flow is measured using a mass flow meter, you must calculate...) For each gas-liquid separator for which flow is measured using a volumetric flow meter, you must...) To aggregate production data, you must sum the mass of all of the CO2 separated at each gas-liquid...

  4. Two-phase flow measurements with advanced instrumented spool pieces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turnage, K.C.

    1980-09-01

    A series of two-phase, air-water and steam-water tests performed with instrumented piping spool pieces is described. The behavior of the three-beam densitometer, turbine meter, and drag flowmeter is discussed in terms of two-phase models. Results from application of some two-phase mass flow models to the recorded spool piece data are shown. Results of the study are used to make recommendations regarding spool piece design, instrument selection, and data reduction methods to obtain more accurate measurements of two-phase flow parameters. 13 refs., 23 figs., 1 tab.

  5. An ex ante analysis on the use of activity meters for automated estrus detection: to invest or not to invest?

    PubMed

    Rutten, C J; Steeneveld, W; Inchaisri, C; Hogeveen, H

    2014-11-01

    The technical performance of activity meters for automated detection of estrus in dairy farming has been studied, and such meters are already used in practice. However, information on the economic consequences of using activity meters is lacking. The current study analyzes the economic benefits of a sensor system for detection of estrus and appraises the feasibility of an investment in such a system. A stochastic dynamic simulation model was used to simulate reproductive performance of a dairy herd. The number of cow places in this herd was fixed at 130. The model started with 130 randomly drawn cows (in a Monte Carlo process) and simulated calvings and replacement of these cows in subsequent years. Default herd characteristics were a conception rate of 50%, an 8-wk dry-off period, and an average milk production level of 8,310 kg per cow per 305 d. Model inputs were derived from real farm data and expertise. For the analysis, visual detection by the farmer ("without" situation) was compared with automated detection with activity meters ("with" situation). For visual estrus detection, an estrus detection rate of 50% and a specificity of 100% were assumed. For automated estrus detection, an estrus detection rate of 80% and a specificity of 95% were assumed. The results of the cow simulation model were used to estimate the difference between the annual net cash flows in the "with" and "without" situations (marginal financial effect) and the internal rate of return (IRR) as profitability indicators. The use of activity meters led to improved estrus detection and, therefore, to a decrease in the average calving interval and subsequent increase in annual milk production. For visual estrus detection, the average calving interval was 419 d and average annual milk production was 1,032,278 kg. For activity meters, the average calving interval was 403 d and the average annual milk production was 1,043,398 kg. It was estimated that the initial investment in activity meters would cost €17,728 for a herd of 130 cows, with an additional cost of €90 per year for the replacement of malfunctioning activity meters. Changes in annual net cash flows arising from using an activity meter included extra revenues from increased milk production and number of calves sold, increased costs from more inseminations, calvings, and feed consumption, and reduced costs from fewer culled cows and less labor for estrus detection. These changes in cash flows were caused mainly by changes in the technical results of the simulated dairy herds, which arose from differences in the estrus detection rate and specificity between the "with" and "without" situations. The average marginal financial effect in the "with" and "without" situations was €2,827 for the baseline scenario, with an average IRR of 11%. The IRR is a measure of the return on invested capital. Investment in activity meters was generally profitable. The most influential assumptions on the profitability of this investment were the assumed culling rules and the increase in sensitivity of estrus detection between the "without" and the "with" situation. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Effect of altitude on spirometric parameters and the performance of peak flow meters.

    PubMed Central

    Pollard, A. J.; Mason, N. P.; Barry, P. W.; Pollard, R. C.; Collier, D. J.; Fraser, R. S.; Miller, M. R.; Milledge, J. S.

    1996-01-01

    BACKGROUND: Portable peak flow meters are used in clinical practice for measurement of peak expiratory flow (PEF) at many different altitudes throughout the world. Some PEF meters are affected by gas density. This study was undertaken to establish which type of meter is best for use above sea level and to determine changes in spirometric measurements at altitude. METHODS: The variable orifice mini-Wright peak flow meter was compared with the fixed orifice Micro Medical Microplus turbine microspirometer at sea level and at Everest Base Camp (5300 m). Fifty one members of the 1994 British Mount Everest Medical Expedition were studied (age range, 19-55). RESULTS: Mean forced vital capacity (FVC) fell by 5% and PEF rose by 25.5%. However, PEF recorded with the mini-Wright peak flow meter underestimated PEF by 31%, giving readings 6.6% below sea level values. FVC was lowest in the mornings and did not improve significantly with acclimatisation. Lower PEF values were observed on morning readings and were associated with higher acute mountain sickness scores, although the latter may reflect decreased effort in those with acute mountain sickness. There was no change in forced expiratory volume in one second (FEV1) at altitude when measured with the turbine microspirometer. CONCLUSIONS: The cause of the fall in FVC at 5300 m is unknown but may be attributed to changes in lung blood volume, interstitial lung oedema, or early airways closure. Variable orifice peak flow meters grossly underestimate PEF at altitude and fixed orifice devices are therefore preferable where accurate PEF measurements are required above sea level. PMID:8711651

  7. 40 CFR 1065.225 - Intake-air flow meter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

  8. 40 CFR 1065.225 - Intake-air flow meter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

  9. 40 CFR 1065.225 - Intake-air flow meter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

  10. Guide to Flow Measurement for Electric Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Frieman, Jason D.; Walker, Mitchell L. R.; Snyder, Steve

    2013-01-01

    In electric propulsion (EP) systems, accurate measurement of the propellant mass flow rate of gas or liquid to the thruster and external cathode is a key input in the calculation of thruster efficiency and specific impulse. Although such measurements are often achieved with commercial mass flow controllers and meters integrated into propellant feed systems, the variability in potential propellant options and flow requirements amongst the spectrum of EP power regimes and devices complicates meter selection, integration, and operation. At the direction of the Committee on Standards for Electric Propulsion Testing, a guide was jointly developed by members of the electric propulsion community to establish a unified document that contains the working principles, methods of implementation and analysis, and calibration techniques and recommendations on the use of mass flow meters in laboratory and spacecraft electric propulsion systems. The guide is applicable to EP devices of all types and power levels ranging from microthrusters to high-power ion engines and Hall effect thrusters. The establishment of a community standard on mass flow metering will help ensure the selection of the proper meter for each application. It will also improve the quality of system performance estimates by providing comprehensive information on the physical phenomena and systematic errors that must be accounted for during the analysis of flow measurement data. This paper will outline the standard methods and recommended practices described in the guide titled "Flow Measurement for Electric Propulsion Systems."

  11. An Analysis of the Loads on and Dynamic Response of a Floating Flexible Tube in Waves and Currents

    DTIC Science & Technology

    2014-05-09

    the tube about 4.57 meters. The CFD code associated with the SolidWorks Flow Simulation tool was applied for this application. Flow Simulation uses...Liquid-Filled Membrane Structure in Waves," Journal of Fluids and Structures, no. 9, pp. 937-956, 1995. [16] SolidWorks , " Flow Simulation 2012...influence of Reynolds number on the drag coefficient. Simulations were performed with the 100% full (solid) model with flow velocities that yielded

  12. A proposal of optimal sampling design using a modularity strategy

    NASA Astrophysics Data System (ADS)

    Simone, A.; Giustolisi, O.; Laucelli, D. B.

    2016-08-01

    In real water distribution networks (WDNs) are present thousands nodes and optimal placement of pressure and flow observations is a relevant issue for different management tasks. The planning of pressure observations in terms of spatial distribution and number is named sampling design and it was faced considering model calibration. Nowadays, the design of system monitoring is a relevant issue for water utilities e.g., in order to manage background leakages, to detect anomalies and bursts, to guarantee service quality, etc. In recent years, the optimal location of flow observations related to design of optimal district metering areas (DMAs) and leakage management purposes has been faced considering optimal network segmentation and the modularity index using a multiobjective strategy. Optimal network segmentation is the basis to identify network modules by means of optimal conceptual cuts, which are the candidate locations of closed gates or flow meters creating the DMAs. Starting from the WDN-oriented modularity index, as a metric for WDN segmentation, this paper proposes a new way to perform the sampling design, i.e., the optimal location of pressure meters, using newly developed sampling-oriented modularity index. The strategy optimizes the pressure monitoring system mainly based on network topology and weights assigned to pipes according to the specific technical tasks. A multiobjective optimization minimizes the cost of pressure meters while maximizing the sampling-oriented modularity index. The methodology is presented and discussed using the Apulian and Exnet networks.

  13. An investigation of deformation and fluid flow at subduction zones using newly developed instrumentation and finite element modeling

    NASA Astrophysics Data System (ADS)

    Labonte, Alison Louise

    Detecting seafloor deformation events in the offshore convergent margin environment is of particular importance considering the significant seismic hazard at subduction zones. Efforts to gain insight into the earthquake cycle have been made at the Cascadia and Costa Rica subduction margins through recent expansions of onshore GPS and seismic networks. While these studies have given scientists the ability to quantify and locate slip events in the seismogenic zone, there is little technology available for adequately measuring offshore aseismic slip. This dissertation introduces an improved flow meter for detecting seismic and aseismic deformation in submarine environments. The value of such hydrologic measurements for quantifying the geodetics at offshore margins is verified through a finite element modeling (FEM) study in which the character of deformation in the shallow subduction zone is determined from previously recorded hydrologic events at the Costa Rica Pacific margin. Accurately sensing aseismic events is one key to determining the stress state in subduction zones as these slow-slip events act to load or unload the seismogenic zone during the interseismic period. One method for detecting seismic and aseismic strain events is to monitor the hydrogeologic response to strain events using fluid flow meters. Previous instrumentation, the Chemical Aqueous Transport (CAT) meter which measures flow rates through the sediment-water interface, can detect transient events at very low flowrates, down to 0.0001 m/yr. The CAT meter performs well in low flow rate environments and can capture gradual changes in flow rate, as might be expected during ultra slow slip events. However, it cannot accurately quantify high flow rates through fractures and conduits, nor does it have the temporal resolution and accuracy required for detecting transient flow events associated with rapid deformation. The Optical Tracer Injection System (OTIS) developed for this purpose is an electronic flow meter that can measure flow rates of 0.1 to >500 m/yr at a temporal resolution of 30 minutes to 0.5 minutes, respectively. Test deployments of the OTIS at cold seeps in the transpressional Monterey Bay demonstrated the OTIS functionality over this range of flow environments. Although no deformation events were detected during these test deployments, the OTIS's temporally accurate measurements at the vigorously flowing Monterey Bay cold seep rendered valuable insight into the plumbing of the seep system. In addition to the capability to detect transient flow events, a primary functional requirement of the OTIS was the ability to communicate and transfer data for long-term real-time monitoring deployments. Real-time data transfer from the OTIS to the desktop was successful during a test deployment of the Nootka Observatory, an acoustically-linked moored-buoy system. A small array of CAT meters was also deployed at the Nootka transform-Cascadia subduction zone triple junction. Four anomalous flow rate events were observed across all four meters during the yearlong deployment. Although the records have low temporal accuracy, a preliminary explanation for the regional changes in flow rate is made through comparison between flow rate records and seismic records. The flow events are thought to be a result of a tectonic deformation event, possibly with an aseismic component. Further constraints are not feasible given the unknown structure of faulting near the triple junction. In a final proof of concept study, I find that use these hydrologic instruments, which capture unique aseismic flow rate patterns, is a valuable method for extracting information about deformation events on the decollement in the offshore subduction zone margin. Transient flow events observed in the frontal prism during a 1999--2000 deployment of CAT meters on the Costa Rica Pacific margin suggest episodic slow-slip deformation events may be occurring in the shallow subduction zone. The FEM study to infer the character of the hypothetical deformation event driving flow transients verify that indeed, a shallow slow-slip event can reproduce the unique flow rate patterns observed. Along (trench) strike variability in the rupture initiation location, and bidirectional propagation, is one way to explain the opposite sign of flow rate transients observed at different along-strike distances. The larger question stimulated by this dissertation project, is: What are the controls on fault mechanics in offshore subduction zone environments? It appears the shallow subduction zone plate interface doesn't behave solely in response to frictional properties of the sediment lining the decollement. Shallow episodic slip at the Costa Rica Pacific margin and further north off Nicaragua, where a slow earthquake broke through the shallow 'stable-sliding' zone and resulted in a tsunami, are potentially conceived through the normally faulted incoming basement topography. Scientists should seek to map out the controls of faulting mechanics, whatever they may be, at all temporal and spatial scales in order to understand these dynamic subduction zone systems. The quest to understanding these controls, in part, requires the characterization of aseismic and seismic strain occurring over time and space. The techniques presented in this dissertation advance scientists' capability for quantifying such strains. With the new instrumentation presented here, long-term real-time observatory networks on the seafloor, and modeling for characterization of deformation events, the pieces of the subduction zone earthquake cycle puzzle may start to come together.

  14. The accuracy of portable peak flow meters.

    PubMed

    Miller, M R; Dickinson, S A; Hitchings, D J

    1992-11-01

    The variability of peak expiratory flow (PEF) is now commonly used in the diagnosis and management of asthma. It is essential for PEF meters to have a linear response in order to obtain an unbiased measurement of PEF variability. As the accuracy and linearity of portable PEF meters have not been rigorously tested in recent years this aspect of their performance has been investigated. The response of several portable PEF meters was tested with absolute standards of flow generated by a computer driven, servo controlled pump and their response was compared with that of a pneumotachograph. For each device tested the readings were highly repeatable to within the limits of accuracy with which the pointer position can be assessed by eye. The between instrument variation in reading for six identical devices expressed as a 95% confidence limit was, on average across the range of flows, +/- 8.5 l/min for the Mini-Wright, +/- 7.9 l/min for the Vitalograph, and +/- 6.4 l/min for the Ferraris. PEF meters based on the Wright meter all had similar error profiles with overreading of up to 80 l/min in the mid flow range from 300 to 500 l/min. This overreading was greatest for the Mini-Wright and Ferraris devices, and less so for the original Wright and Vitalograph meters. A Micro-Medical Turbine meter was accurate up to 400 l/min and then began to underread by up to 60 l/min at 720 l/min. For the low range devices the Vitalograph device was accurate to within 10 l/min up to 200 l/min, with the Mini-Wright overreading by up to 30 l/min above 150 l/min. Although the Mini-Wright, Ferraris, and Vitalograph meters gave remarkably repeatable results their error profiles for the full range meters will lead to important errors in recording PEF variability. This may lead to incorrect diagnosis and bias in implementing strategies of asthma treatment based on PEF measurement.

  15. The accuracy of portable peak flow meters.

    PubMed Central

    Miller, M R; Dickinson, S A; Hitchings, D J

    1992-01-01

    BACKGROUND: The variability of peak expiratory flow (PEF) is now commonly used in the diagnosis and management of asthma. It is essential for PEF meters to have a linear response in order to obtain an unbiased measurement of PEF variability. As the accuracy and linearity of portable PEF meters have not been rigorously tested in recent years this aspect of their performance has been investigated. METHODS: The response of several portable PEF meters was tested with absolute standards of flow generated by a computer driven, servo controlled pump and their response was compared with that of a pneumotachograph. RESULTS: For each device tested the readings were highly repeatable to within the limits of accuracy with which the pointer position can be assessed by eye. The between instrument variation in reading for six identical devices expressed as a 95% confidence limit was, on average across the range of flows, +/- 8.5 l/min for the Mini-Wright, +/- 7.9 l/min for the Vitalograph, and +/- 6.4 l/min for the Ferraris. PEF meters based on the Wright meter all had similar error profiles with overreading of up to 80 l/min in the mid flow range from 300 to 500 l/min. This overreading was greatest for the Mini-Wright and Ferraris devices, and less so for the original Wright and Vitalograph meters. A Micro-Medical Turbine meter was accurate up to 400 l/min and then began to underread by up to 60 l/min at 720 l/min. For the low range devices the Vitalograph device was accurate to within 10 l/min up to 200 l/min, with the Mini-Wright overreading by up to 30 l/min above 150 l/min. CONCLUSION: Although the Mini-Wright, Ferraris, and Vitalograph meters gave remarkably repeatable results their error profiles for the full range meters will lead to important errors in recording PEF variability. This may lead to incorrect diagnosis and bias in implementing strategies of asthma treatment based on PEF measurement. PMID:1465746

  16. Multiphase flowmeter successfully measures three-phase flow at extremely high gas-volume fractions -- Gulf of Suez, Egypt

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leggett, R.B.; Borling, D.C.; Powers, B.S.

    1998-02-01

    A multiphase flowmeter (MPFM) installed in offshore Egypt has accurately measured three-phase flow in extremely gassy flow conditions. The meter is completely nonintrusive, with no moving parts, requires no flow mixing before measurement, and has no bypass loop to remove gas before multiphase measurement. Flow regimes observed during the field test of this meter ranged from severe slugging to annular flow caused by the dynamics of gas-lift gas in the production stream. Average gas-volume fraction ranged from 93 to 98% during tests conducted on seven wells. The meter was installed in the Gulf of Suez on a well protector platformmore » in the Gulf of Suez Petroleum Co. (Gupco) October field, and was placed in series with a test separator located on a nearby production platform. Wells were individually tested with flow conditions ranging from 1,300 to 4,700 B/D fluid, 2.4 to 3.9 MMscf/D of gas, and water cuts from 1 to 52%. The meter is capable of measuring water cuts up to 100%. Production was routed through both the MPFM and the test separator simultaneously as wells flowed with the assistance of gas-lift gas. The MPFM measured gas and liquid rates to within {+-} 10% of test-separator reference measurement flow rates, and accomplished this at gas-volume fractions from 93 to 96%. At higher gas-volume fractions up to 98%, accuracy deteriorated but the meter continued to provide repeatable results.« less

  17. DEVELOPMENT AND DEMONSTRATION OF A BIDIRECTIONAL ADVECTIVE FLUX METER FOR SEDIMENT-WATER INTERFACE

    EPA Science Inventory

    A bidirectional advective flux meter for measuring water transport across the sediment-water interface has been successfully developed and field tested. The flow sensor employs a heat-pulse technique combined with a flow collection funnel for the flow measurement. Because the dir...

  18. Data system for multiplexed water-current meters

    NASA Technical Reports Server (NTRS)

    Ramsey, C. R.

    1977-01-01

    Flow rates at 32 flood plain locations are measured simultaneously by single digital logic unit with high noise immunity. Water flowing through pygmy current meters rotates element that closes electrical contact once every resolution, so flow rate is measured by counting number of closures in time interval.

  19. Groundwater-Seepage Meter

    NASA Technical Reports Server (NTRS)

    Walthall, Harry G.; Reay, William G.

    1993-01-01

    Instrument measures seepage of groundwater into inland or coastal body of water. Positioned at depth as great as 40 meters, and measures flow at low rate and low pressure differential. Auxiliary pressure meter provides data for correlation of flow of groundwater with tides and sea states. Seepage meter operates independently for several weeks. Its sampling rate adjusted to suit hydrologic conditions; to measure more frequently when conditions changing rapidly. Used in water-quality management and for biological and geological research. Potential industrial uses include measurement of seepage of caustic and corrosive liquids.

  20. Fuel cell membrane hydration and fluid metering

    DOEpatents

    Jones, Daniel O.; Walsh, Michael M.

    2003-01-01

    A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).

  1. Geophysical Investigation Along the Great Miami River From New Miami to Charles M. Bolton Well Field, Cincinnati, Ohio

    USGS Publications Warehouse

    Sheets, R.A.; Dumouchelle, D.H.

    2009-01-01

    Three geophysical profiling methods were tested to help characterize subsurface materials at selected transects along the Great Miami River, in southwestern Ohio. The profiling methods used were continuous seismic profiling (CSP), continuous resistivity profiling (CRP), and continuous electromagnetic profiling (CEP). Data were collected with global positioning systems to spatially locate the data along the river. The depth and flow conditions of the Great Miami River limited the amount and quality of data that could be collected with the CSP and CRP methods. Data from the CSP were generally poor because shallow reflections (less than 5 meters) were mostly obscured by strong multiple reflections and deep reflections (greater than 5 meters) were sparse. However, modeling of CRP data indicated broad changes in subbottom geology, primarily below about 3 to 5 meters. Details for shallow electrical conductivity (resistivity) (less than 3 meters) were limited because of the 5-meter electrode spacing used for the surveys. For future studies of this type, a cable with 3-meter electrode spacing (or perhaps even 1-meter spacing) might best be used in similar environments to determine shallow electrical properties of the stream-bottom materials. CEP data were collected along the entire reach of the Great Miami River. The CRP and CEP data did not correlate well, but the CRP electrode spacing probably limited the correlation. Middle-frequency (3,510 hertz) and high-frequency (15,030 hertz) CEP data were correlated to water depth. Low-frequency (750 hertz) CEP data indicate shallow (less than 5-meter) changes in electrical conductivity. Given the variability in depth and flow conditions on a river such as the Great Miami, the CEP method worked better than either the CSP or CRP methods.

  2. Application of a Laser Interferometer Skin-Friction Meter in Complex Flows

    NASA Technical Reports Server (NTRS)

    Monson, D. J.; Driver, D. M.; Szodruch, J.

    1981-01-01

    A nonintrusive skin-friction meter has been found useful for a variety of complex wind-tunnel flows. This meter measures skin friction with a remotely located laser interferometer that monitors the thickness change of a thin oil film. Its accuracy has been proven in a low-speed flat-plate flow. The wind-tunnel flows described here include sub-sonic separated and reattached flow over a rearward-facing step, supersonic flow over a flat plate at high Reynolds numbers, and supersonic three - dimensional vortical flow over the lee of a delta wing at angle of attack. The data-reduction analysis was extended to apply to three-dimensional flows with unknown flow direction, large pressure and shear gradients, and large oil viscosity changes with time. The skin friction measurements were verified, where possible, with results from more conventional techniques and also from theoretical computations.

  3. Numerical investigation of influence on heat transfer characteristics to pneumatically conveyed dense phase flow by selecting models and boundary conditions

    NASA Astrophysics Data System (ADS)

    Zheng, Y.; Liu, Q.; Li, Y.

    2012-03-01

    Solids moving with a gas stream in a pipeline can be found in many industrial processes, such as power generation, chemical, pharmaceutical, food and commodity transfer processes. A mass flow rate of the solids is important characteristic that is often required to be measured (and controlled) to achieve efficient utilization of energy and raw materials in pneumatic conveying systems. The methods of measuring the mass flow rate of solids in a pneumatic pipeline can be divided into direct and indirect (inferential) measurements. A thermal solids' mass flow-meter, in principle, should ideally provide a direct measurement of solids flow rate, regardless of inhomogeneities in solids' distribution and environmental impacts. One key issue in developing a thermal solids' mass flow-meter is to characterize the heat transfer between the hot pipe wall and the gas-solids dense phase flow. The Eulerian continuum modeling with gas-solid two phases is the most common method for pneumatic transport. To model a gas-solid dense phase flow passing through a heated region, the gas phase is described as a continuous phase and the particles as the second phase. This study aims to describe the heat transfer characteristics between the hot wall and the gas-solids dense phase flow in pneumatic pipelines by modeling a turbulence gas-solid plug passing through the heated region which involves several actual and crucial issues: selections of interphase exchange coefficient, near-wall region functions and different wall surface temperatures. A sensitivity analysis was discussed to identify the influence on the heat transfer characteristics by selecting different interphase exchange coefficient models and different boundary conditions. Simulation results suggest that sensitivity analysis in the choice of models is very significant. The simulation results appear to show that a combination of choosing the Syamlal-O'Brien interphase exchange coefficient model and the standard k-ɛ model along with the standard wall function model might be the best approach, by which, the simulation data seems to be closest to the experimental results.

  4. Estimated probabilities, volumes, and inundation areas depths of potential postwildfire debris flows from Carbonate, Slate, Raspberry, and Milton Creeks, near Marble, Gunnison County, Colorado

    USGS Publications Warehouse

    Stevens, Michael R.; Flynn, Jennifer L.; Stephens, Verlin C.; Verdin, Kristine L.

    2011-01-01

    During 2009, the U.S. Geological Survey, in cooperation with Gunnison County, initiated a study to estimate the potential for postwildfire debris flows to occur in the drainage basins occupied by Carbonate, Slate, Raspberry, and Milton Creeks near Marble, Colorado. Currently (2010), these drainage basins are unburned but could be burned by a future wildfire. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of postwildfire debris-flow occurrence and debris-flow volumes for drainage basins occupied by Carbonate, Slate, Raspberry, and Milton Creeks near Marble. Data for the postwildfire debris-flow models included drainage basin area; area burned and burn severity; percentage of burned area; soil properties; rainfall total and intensity for the 5- and 25-year-recurrence, 1-hour-duration-rainfall; and topographic and soil property characteristics of the drainage basins occupied by the four creeks. A quasi-two-dimensional floodplain computer model (FLO-2D) was used to estimate the spatial distribution and the maximum instantaneous depth of the postwildfire debris-flow material during debris flow on the existing debris-flow fans that issue from the outlets of the four major drainage basins. The postwildfire debris-flow probabilities at the outlet of each drainage basin range from 1 to 19 percent for the 5-year-recurrence, 1-hour-duration rainfall, and from 3 to 35 percent for 25-year-recurrence, 1-hour-duration rainfall. The largest probabilities for postwildfire debris flow are estimated for Raspberry Creek (19 and 35 percent), whereas estimated debris-flow probabilities for the three other creeks range from 1 to 6 percent. The estimated postwildfire debris-flow volumes at the outlet of each creek range from 7,500 to 101,000 cubic meters for the 5-year-recurrence, 1-hour-duration rainfall, and from 9,400 to 126,000 cubic meters for the 25-year-recurrence, 1-hour-duration rainfall. The largest postwildfire debris-flow volumes were estimated for Carbonate Creek and Milton Creek drainage basins, for both the 5- and 25-year-recurrence, 1-hour-duration rainfalls. Results from FLO-2D modeling of the 5-year and 25-year recurrence, 1-hour rainfalls indicate that the debris flows from the four drainage basins would reach or nearly reach the Crystal River. The model estimates maximum instantaneous depths of debris-flow material during postwildfire debris flows that exceeded 5 meters in some areas, but the differences in model results between the 5-year and 25-year recurrence, 1-hour rainfalls are small. Existing stream channels or topographic flow paths likely control the distribution of debris-flow material, and the difference in estimated debris-flow volume (about 25 percent more volume for the 25-year-recurrence, 1-hour-duration rainfall compared to the 5-year-recurrence, 1-hour-duration rainfall) does not seem to substantially affect the estimated spatial distribution of debris-flow material. Historically, the Marble area has experienced periodic debris flows in the absence of wildfire. This report estimates the probability and volume of debris flow and maximum instantaneous inundation area depths after hypothetical wildfire and rainfall. This postwildfire debris-flow report does not address the current (2010) prewildfire debris-flow hazards that exist near Marble.

  5. Simulation of hydrodynamics and solute transport in the Pamlico River estuary, North Carolina

    USGS Publications Warehouse

    Bales, Jerad; Robbins, Jeanne C.

    1995-01-01

    An investigation was conducted to characterize flow, circulation, and solute transport in the Pamlico River estuary, North Carolina. The study included a detailed field-measurement program and the calibration, validation, and application of a physically realistic numerical model of hydro- dynamics and transport. Water level, salinity, water temperature, wind speed and direction, and current data were collected during March 1988 through September 1992, and were used to characterize physical conditions in the estuary. Data from pre- existing streamflow gaging stations and meteoro- logical stations were also used. A two-dimensional vertically averaged hydrodynamic and solute transport model was applied to the 48-kilometer study reach. The model domain was discretized into 5,620 separate 200- by 200-meter computational cells. Model calibration was achieved through adjustment of parameters for June 14-30, 1991. Data from selected periods in 1989 and 1991 were used for model validation. Water levels used for model calibration and validation ranged from -0.052 to 0.698 meter; salinities ranged from 0.1 to 13.1 parts per thousand; and wind speeds ranged from calm to 22 meters per second. The model was tested for stratified and unstratified conditions. Simulated and observed data were used to evaluate model performance. The calibrated model was applied for selected periods in 1989 and 1991. Instantaneous flows were simulated at each boundary and at mid- estuary. Circulation patterns were characterized using vector plots, particle tracking, and solute transport. Particle tracks showed that materials released at mid-estuary may remain in the system for 25 days or longer.

  6. Continuous flow measurements using ultrasonic velocity meters - an update

    USGS Publications Warehouse

    Oltmann, Rick

    1995-01-01

    An article in the summer 1993 Newsletter described USGS work to continously monitor tidal flows in the delta using ultrasonic velocity meters.  This article updates progress since 1993, including new installations, results of data analysis, damage during this year's high flows, and the status of each site.

  7. "Physically-based" numerical experiment to determine the dominant hillslope processes during floods?

    NASA Astrophysics Data System (ADS)

    Gaume, Eric; Esclaffer, Thomas; Dangla, Patrick; Payrastre, Olivier

    2016-04-01

    To study the dynamics of hillslope responses during flood event, a fully coupled "physically-based" model for the combined numerical simulation of surface runoff and underground flows has been developed. A particular attention has been given to the selection of appropriate numerical schemes for the modelling of both processes and of their coupling. Surprisingly, the most difficult question to solve, from a numerical point of view, was not related to the coupling of two processes with contrasted kinetics such as surface and underground flows, but to the high gradient infiltration fronts appearing in soils, source of numerical diffusion, instabilities and sometimes divergence. The model being elaborated, it has been successfully tested against results of high quality experiments conducted on a laboratory sandy slope in the early eighties, which is still considered as a reference hillslope experimental setting (Abdul & Guilham). The model appeared able to accurately simulate the pore pressure distributions observed in this 1.5 meter deep and wide laboratory hillslope, as well as its outflow hydrograph shapes and the measured respective contributions of direct runoff and groundwater to these outflow hydrographs. Based on this great success, the same model has been used to simulate the response of a theoretical 100-meter wide and 10% sloped hillslope, with a 2 meter deep pervious soil and impervious bedrock. Three rain events have been tested: a 100 millimeter rainfall event over 10 days, over 1 day or over one hour. The simulated responses are hydrologically not realistic and especially the fast component of the response, that is generally observed in the real-world and explains flood events, is almost absent of the simulated response. Thinking a little about the whole problem, the simulation results appears totally logical according to the proposed model. The simulated response, in fact a recession hydrograph, corresponds to a piston flow of a relatively uniformly saturated hillslope leading to a constant discharge over several days. Some ingredients are clearly missing in the proposed model to reproduce hydrologically sensible responses. Heterogeneities are necessary to generate a variety of residence times and especially preferential flows must clearly be present to generate the fast component of hillslope responses. The importance of preferential flows in hillslope hydrology has been confirmed since this reported failure by several hillslope field experiments. We let also the readers draw their own conclusions about the numerous numerical models, that look very much alike the model proposed here, even if generally much more simplified, but representing the watersheds as much too homogeneous neglecting heterogeneities and preferential flows and pretending to be "physically based"…

  8. THERMALWATER FLOW METER. Hot Springs National Park, Bathhouse Row, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    THERMAL-WATER FLOW METER. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  9. Parametric test results of a swirl-can combustor

    NASA Technical Reports Server (NTRS)

    Niedzwiecki, R. W.; Jones, R. E.

    1973-01-01

    Pollutant levels of oxides of nitrogen, unburned hydrocarbons, and carbon monoxide were measured for three models of an experimental, annular swirl can combustor. The combustor was 1.067 meters in outer diameter, incorporated 120 modules, and was specifically designed for elevated exit temperature performance. Test conditions included combustor inlet temperatures of 589, 756 and 839 K, inlet pressures of 3 to 6.4 atmospheres, reference velocities of 21 to 38 meters per second and combustor equivalence ratios, based on total combustor flows of 0.206 to 1.028. Maximum oxides of nitrogen emission index values occurred at an equivalence ratio of 0.7 with lower values measured for both higher and lower equivalence ratios. Oxides of nitrogen concentrations, to the 0.7 level with 756 K inlet air, were correlated for the three models by a combined parameter consisting of measured flow and geometric parameters. Effects of the individual parameters comprising the correlation are also presented.

  10. Volcanic recycling of carbonate deposits on Mars

    NASA Technical Reports Server (NTRS)

    Schaefer, M. W.

    1992-01-01

    One question of great interest to those who study the evolution of the Martian atmosphere is: if there was an early, dense atmosphere that was removed, is there any mechanism that could restore it? In the case of an atmosphere removed largely by the formation of carbonates, the only obvious means of restoring it is by the thermal decomposition of the carbonates. Decomposition of carbonates under turbulently flowing lava holds great promise as a means of resupplying the atmosphere with CO2. Huppert and colleagues have modeled the emplacement of terrestrial komatiite flows and found that komatiites, even when flowing over previously emplaced and cooled komatiite flows, could melt and erode this rock to a significant depth. Based on this work, I have begun modeling the erosion of Martian carbonate deposits under turbulently flowing, komatiitic lava. Initial results from this modeling indicate that a high-volume lava flow, emerging at a temperature of, say, 1600 degrees, is capable of eroding several meters of carbonate deposits per day. If such a flow is active for a hundred days, several hundreds of meters of carbonate could be decomposed. If this process occurred over a large area, a bar or more of CO2 could be injected back into the atmosphere over an extremely short period of time. The implications of such an occurrence are intriguing. For instance, if a relatively late pulse of volcanism (such as is suggested by Frey) were to cause a large flow of lava over carbonate deposits in the northern lowlands, the resulting pulse of CO2 into the atmosphere could conceivably restore the climate to one in which liquid water could exist on the surface, or ice could flow.

  11. Evaluation of four fast-response flow measurement devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gero, A.J.; Suppers, K.L.; Tomb, T.F.

    1988-01-01

    The Federal Mine Safety and Health Act of 1977 requires that sampling of dust in coal mine environments be conducted with an approved sampler operating at a flow rate of 2.0 liters of air per minute or at such other flow rate as prescribed by the Secretaries of Labor and of Health and Human Services. Standard procedures for calibration of these samplers within the Mine Safety and Health Administration utilize either a 3.0 liter capacity wet test meter or a 1.0 liter soap film calibrator. Several new flow calibrating devices have become commercially available. This paper describes an evaluation conductedmore » on four such devices: the Mast Model 823-2 bubble flowmeter, the Buck Calibrator, the Kurz Model 541S mass flowmeter and the Kurz Pocket Calibrator. The precision of a series of measurements made with each instrument was compared to the precision of a series of measurements made with the wet test meter. The comparison showed that the variability of calibration measurements obtained with the fast response flow calibrators was between 1.5 and 4.5 times larger than that obtained with the WTM; however, with all of the calibration devices evaluated, three repetitive measurements were sufficient to obtain a precision of {plus minus}0.1 liters per minute. 4 refs., 2 figs., 1 tab.« less

  12. Preliminary soil-slip susceptibility maps, southwestern California

    USGS Publications Warehouse

    Morton, Douglas M.; Alvarez, Rachel M.; Campbell, Russell H.; Digital preparation by Bovard, Kelly R.; Brown, D.T.; Corriea, K.M.; Lesser, J.N.

    2003-01-01

    This group of maps shows relative susceptibility of hill slopes to the initiation sites of rainfall-triggered soil slip-debris flows in southwestern California. As such, the maps offer a partial answer to one part of the three parts necessary to predict the soil-slip/debris-flow process. A complete prediction of the process would include assessments of “where”, “when”, and “how big”. These maps empirically show part of the “where” of prediction (i.e., relative susceptibility to sites of initiation of the soil slips) but do not attempt to show the extent of run out of the resultant debris flows. Some information pertinent to “when” the process might begin is developed. “When” is determined mostly by dynamic factors such as rainfall rate and duration, for which local variations are not amenable to long-term prediction. “When” information is not provided on the maps but is described later in this narrative. The prediction of “how big” is addressed indirectly by restricting the maps to a single type of landslide process—soil slip-debris flows. The susceptibility maps were created through an iterative process from two kinds of information. First, locations of sites of past soil slips were obtained from inventory maps of past events. Aerial photographs, taken during six rainy seasons that produced abundant soil slips, were used as the basis for soil slip-debris flow inventory. Second, digital elevation models (DEM) of the areas that were inventoried were used to analyze the spatial characteristics of soil slip locations. These data were supplemented by observations made on the ground. Certain physical attributes of the locations of the soil-slip debris flows were found to be important and others were not. The most important attribute was the mapped bedrock formation at the site of initiation of the soil slip. However, because the soil slips occur in surficial materials overlying the bedrocks units, the bedrock formation can only serve as a surrogate for the susceptibility of the overlying surficial materials. The maps of susceptibility were created from those physical attributes learned to be important from the inventories. The multiple inventories allow a model to be created from one set of inventory data and evaluated with others. The resultant maps of relative susceptibility represent the best estimate generated from available inventory and DEM data. Slope and aspect values used in the susceptibility analysis were 10-meter DEM cells at a scale of 1:24,000. For most of the area 10-meter DEMs were available; for those quadrangles that have only 30-meter DEMs, the 30-meter DEMS were resampled to 10-meters to maintain resolution of 10-meter cells. Geologic unit values used in the susceptibility analysis were five-meter cells. For convenience, the soil slip susceptibility values are assembled on 1:100,000-scale bases. Any area of the 1:100,000-scale maps can be transferred to 1:24,000-scale base without any loss of accuracy. Figure 32 is an example of part of a 1:100,000-scale susceptibility map transferred back to a 1:24,000-scale quadrangle.

  13. Fifty-year flood-inundation maps for La Lima, Honduras

    USGS Publications Warehouse

    Mastin, Mark C.; Olsen, T.D.

    2002-01-01

    After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of La Lima that would be inundated by Rio Chamelecon with a discharge of 500 cubic meters per second, the approximate capacity of the river channel through the city of La Lima. The 50-year flood (2,400 cubic meters per second), the original design flow to be mapped, would inundate the entire area surveyed for this municipality. Because water-surface elevations of the 50-year flood could not be mapped properly without substantially expanding the area of the survey, the available data were used instead to estimate the channel capacity of Rio Chamelecon in La Lima by trial-and-error runs of different flows in a numerical model and to estimate the increase in height of levees needed to contain flows of 1,000 and 2,400 cubic meters per second. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of La Lima as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for various discharges on Rio Chamelecon at La Lima were determined using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and ground surveys at three bridges. Top-of-levee or top-of-channel-bank elevations and locations at the cross sections were critical to estimating the channel capacity of Rio Chamelecon. These elevations and locations are provided along with the water-surface elevations for the 500-cubic-meter-per-second flow of Rio Chamelecon. Also, water-surface elevations of the 1,000 and 2,400 cubic-meter-per-second flows are provided, assuming that the existing levees are raised to contained the flows.

  14. Development of the Circulation Control Flow Scheme Used in the NTF Semi-Span FAST-MAC Model

    NASA Technical Reports Server (NTRS)

    Jones, Gregory S.; Milholen, William E., II; Chan, David T.; Allan, Brian G.; Goodliff, Scott L.; Melton, Latunia P.; Anders, Scott G.; Carter, Melissa B.; Capone, Francis J.

    2013-01-01

    The application of a circulation control system for high Reynolds numbers was experimentally validated with the Fundamental Aerodynamic Subsonic Transonic Modular Active Control semi-span model in the NASA Langley National Transonic Facility. This model utilized four independent flow paths to modify the lift and thrust performance of a representative advanced transport type of wing. The design of the internal flow paths highlights the challenges associated with high Reynolds number testing in a cryogenic pressurized wind tunnel. Weight flow boundaries for the air delivery system were identified at mildly cryogenic conditions ranging from 0.1 to 10 lbm/sec. Results from the test verified system performance and identified solutions associated with the weight-flow metering system that are linked to internal perforated plates used to achieve flow uniformity at the jet exit.

  15. DETAIL OF THERMALWATER FLOW METER. Hot Springs National Park, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THERMAL-WATER FLOW METER. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  16. 5. FLOW METER AND PIPING SHOWING CONNECTIONS. Hot Springs ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. FLOW METER AND PIPING SHOWING CONNECTIONS. - Hot Springs National Park Bathhouse Row, Maurice Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  17. Simulation of ground-water discharge to Biscayne Bay, southeastern Florida

    USGS Publications Warehouse

    Langevin, Christian David

    2001-01-01

    As part of the Place-Based Studies Program, the U.S. Geological Survey initiated a project in 1996, in cooperation with the U.S. Army Corps of Engineers, to quantify the rates and patterns of submarine ground-water discharge to Biscayne Bay. Project objectives were achieved through field investigations at three sites (Coconut Grove, Deering Estate, and Mowry Canal) along the coastline of Biscayne Bay and through the development and calibration of variable-density, ground-water flow models. Two-dimensional, vertical cross-sectional models were developed for steady-state conditions for the Coconut Grove and Deering Estate transects to quantify local-scale ground-water discharge patterns to Biscayne Bay. A larger regional-scale model was developed in three dimensions to simulate submarine ground-water discharge to the entire bay. The SEAWAT code, which is a combined version of MODFLOW and MT3D, was used to simulate the complex variable-density flow patterns. Field data suggest that ground-water discharge to Biscayne Bay relative to the shoreline is restricted to within 300 meters at Coconut Grove, 600 to 1,000 meters at Deering Estate, and 100 meters at Mowry Canal. The vertical cross-sectional models, which were calibrated to the field data using the assumption of steady state, tend to focus ground-water discharge to within 50 to 200 meters of the shoreline. With homogeneous distributions for aquifer parameters and a constant-concentration boundary for Biscayne Bay, the numerical models could not reproduce the lower ground-water salinities observed beneath the bay, which suggests that further research may be necessary to improve the accuracy of the numerical simulations. Results from the cross-sectional models, which were able to simulate the approximate position of the saltwater interface, suggest that longitudinal dispersivity ranges between 1 and 10 meters, and transverse dispersivity ranges from 0.1 to 1 meter for the Biscayne aquifer. The three-dimensional, regional-scale model was calibrated to ground-water heads, canal baseflow, and the general position of the saltwater interface for nearly a 10-year period from 1989 to 1998. The mean absolute error between observed and simulated head values is 0.15 meter. The mean absolute error between observed and simulated baseflow is 3 x 105 cubic meters per day. The position of the simulated saltwater interface generally matches the position observed in the field, except for areas north of the Miami Canal where the simulated saltwater interface is located about 5 kilometers inland of the observed saltwater interface. Results from the regional-scale model suggest that the average rate of fresh ground-water discharge to Biscayne Bay for the 10-year period (1989-98) is about 2 x 105 cubic meters per day for 100 kilometers of coastline. This simulated discharge rate is about 6 percent of the measured surface-water discharge to Biscayne Bay for the same period. The model also suggests that nearly 100 percent of the fresh ground-water discharge is to the northern half of Biscayne Bay, north of the Cutler Drain Canal. South of the Cutler Drain Canal, coastal lowlands prevent the water table from rising high enough to drive measurable quantities of ground water to Biscayne Bay. Annual variations in sea-level elevation, which can be as large as 0.3 meter, have a substantial effect on rates of ground-water discharge. During 1989-98, simulated rates of ground-water discharge to Biscayne Bay generally are highest when sea level is relatively low.

  18. Mean flow field and surface heating produced by unequal shock interactions at hypersonic speeds

    NASA Technical Reports Server (NTRS)

    Birch, S. F.; Rudy, D. H.

    1975-01-01

    Mean velocity profiles were measured in a free shear layer produced by the interaction of two unequal strength shock waves at hypersonic free-stream Mach numbers. Measurements were made over a unit Reynolds number range of 3,770,000 per meter to 17,400,000 per meter based on the flow on the high velocity side of the shear layer. The variation in measured spreading parameters with Mach number for the fully developed flows is consistent with the trend of the available zero velocity ratio data when the Mach numbers for the data given in this study are taken to be characteristic Mach numbers based on the velocity difference across the mixing layer. Surface measurements in the shear-layer attachment region of the blunt-body model indicate peak local heating and static pressure consistent with other published data. Transition Reynolds numbers were found to be significantly lower than those found in previous data.

  19. Direct Measurement of Proximal Isovelocity Surface Area by Real-Time Three-Dimensional Color Doppler for Quantitation of Aortic Regurgitant Volume: An In Vitro Validation

    PubMed Central

    Pirat, Bahar; Little, Stephen H.; Igo, Stephen R.; McCulloch, Marti; Nosé, Yukihiko; Hartley, Craig J.; Zoghbi, William A.

    2012-01-01

    Objective The proximal isovelocity surface area (PISA) method is useful in the quantitation of aortic regurgitation (AR). We hypothesized that actual measurement of PISA provided with real-time 3-dimensional (3D) color Doppler yields more accurate regurgitant volumes than those estimated by 2-dimensional (2D) color Doppler PISA. Methods We developed a pulsatile flow model for AR with an imaging chamber in which interchangeable regurgitant orifices with defined shapes and areas were incorporated. An ultrasonic flow meter was used to calculate the reference regurgitant volumes. A total of 29 different flow conditions for 5 orifices with different shapes were tested at a rate of 72 beats/min. 2D PISA was calculated as 2π r2, and 3D PISA was measured from 8 equidistant radial planes of the 3D PISA. Regurgitant volume was derived as PISA × aliasing velocity × time velocity integral of AR/peak AR velocity. Results Regurgitant volumes by flow meter ranged between 12.6 and 30.6 mL/beat (mean 21.4 ± 5.5 mL/beat). Regurgitant volumes estimated by 2D PISA correlated well with volumes measured by flow meter (r = 0.69); however, a significant underestimation was observed (y = 0.5x + 0.6). Correlation with flow meter volumes was stronger for 3D PISA-derived regurgitant volumes (r = 0.83); significantly less underestimation of regurgitant volumes was seen, with a regression line close to identity (y = 0.9x + 3.9). Conclusion Direct measurement of PISA is feasible, without geometric assumptions, using real-time 3D color Doppler. Calculation of aortic regurgitant volumes with 3D color Doppler using this methodology is more accurate than conventional 2D method with hemispheric PISA assumption. PMID:19168322

  20. Linking fault pattern with groundwater flow in crystalline rocks at the Grimsel Test Site (Switzerland)

    NASA Astrophysics Data System (ADS)

    Schneeberger, Raphael; Berger, Alfons; Mäder, Urs K.; Niklaus Waber, H.; Kober, Florian; Herwegh, Marco

    2017-04-01

    Water flow across crystalline bedrock is of major interest for deep-seated geothermal energy projects as well as for underground disposal of radioactive waste. In crystalline rocks enhanced fluid flow is related to zones of increased permeability, i.e. to fractures that are associated to fault zones. The flow regime around the Grimsel Test Site (GTS, Central Aar massif) was assessed by establishing a 3D fault zone pattern on a local scale in the GTS underground facility (deca-meter scale) and on a regional scale at the surface (km-scale). The study reveals the existence of a dense fault zone network consisting of several km long and few tens of cm to meter wide, sub-vertically oriented major faults that are connected by tens to hundreds of meters long minor bridging faults. This geometrical information was used as input for the generation of a 3D fault zone network model. The faults originate from ductile shear zones that were reactivated as brittle faults under retrograde conditions during exhumation. Embrittlement and associated dilatancy along the faults provide the pathways for today's groundwater flow. Detection of the actual 3D flow paths is, however, challenging since flow seem to be not planar but rather tube-like. Two strategies are applied to constrain the 3D geometry of the flow tubes: (i) Characterization of the groundwater infiltrating into the GTS (location, yield, hydraulic head, and chemical composition) and (ii) stress modelling on the base of the 3D structural model to unravel potential domains of enhanced fluid flow such as fault plane intersections and domains of dilatancy. At the Grimsel Test Site, hydraulic and structural data demonstrate that the groundwater flow is head-driven from the surface towards the GTS located some 450 m below the surface. The residence time of the groundwater in this surface-near section is >60 years as evidenced by absence of detectable tritium. However, hydraulic heads obtained from interval pressure measurements within boreholes are variable and do not correspond to the overburden above the interval. Underground mapping revealed close spatial relation between water inflow points and faults, major water inflows occur in strongly deformed areas of the GTS. Furthermore, persistent differences in the groundwater chemical composition between infiltration points indicate that connectivity between different water flow paths is poor. Different findings indicate complex flow path geometries. However, domains of enhanced dilatancy and domains with increased number of fault intersections correlate with areas in the underground with 'high' water inflow.

  1. A system for the real time, direct measurement of natural gas flow

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sowell, T.

    1995-12-31

    PMI/Badger Meter, Inc. with partial sponsorship from the Gas Research Institute, has designed and developed direct measurement total energy flow metering instrumentation. As industry demands for improved accuracy and speed of measurement have increased so has the complexity of the overall hardware and software systems. Considering traditional system approaches, few companies have the in house capability of maintaining a complete system. This paper addresses efforts to implement a direct, total gas energy flow metering system which is simple to use and cost effective.

  2. Understanding Hydraulic Fracturing: A Multi-Scale Problem

    DOE PAGES

    Hyman, Jeffrey De'Haven; Gimenez Martinez, Joaquin; Viswanathan, Hari S.; ...

    2016-09-05

    Despite the impact that hydraulic fracturing has had on the energy sector, the physical mechanisms that control its efficiency and environmental impacts remain poorly understood in part because the length scales involved range from nano-meters to kilo-meters. We characterize flow and transport in shale formations across and between these scales using integrated computational, theoretical, and experimental efforts. At the field scale, we use discrete fracture network modeling to simulate production at a well site whose fracture network is based on a site characterization of a shale formation. At the core scale, we use triaxial fracture experiments and a finite-element discrete-elementmore » fracture propagation model with a coupled fluid solver to study dynamic crack propagation in low permeability shale. We use lattice Boltzmann pore-scale simulations and microfluidic experiments in both synthetic and real micromodels to study pore-scale flow phenomenon such as multiphase flow and mixing. A mechanistic description and integration of these multiple scales is required for accurate predictions of production and the eventual optimization of hydrocarbon extraction from unconventional reservoirs.« less

  3. Delineation of the hydrogeologic framework of the Big Sioux aquifer near Sioux Falls, South Dakota, using airborne electromagnetic data

    USGS Publications Warehouse

    Valseth, Kristen J.; Delzer, Gregory C.; Price, Curtis V.

    2018-03-21

    The U.S. Geological Survey, in cooperation with the City of Sioux Falls, South Dakota, began developing a groundwater-flow model of the Big Sioux aquifer in 2014 that will enable the City to make more informed water management decisions, such as delineation of areas of the greatest specific yield, which is crucial for locating municipal wells. Innovative tools are being evaluated as part of this study that can improve the delineation of the hydrogeologic framework of the aquifer for use in development of a groundwater-flow model, and the approach could have transfer value for similar hydrogeologic settings. The first step in developing a groundwater-flow model is determining the hydrogeologic framework (vertical and horizontal extents of the aquifer), which typically is determined by interpreting geologic information from drillers’ logs and surficial geology maps. However, well and borehole data only provide hydrogeologic information for a single location; conversely, nearly continuous geophysical data are collected along flight lines using airborne electromagnetic (AEM) surveys. These electromagnetic data are collected every 3 meters along a flight line (on average) and subsequently can be related to hydrogeologic properties. AEM data, coupled with and constrained by well and borehole data, can substantially improve the accuracy of aquifer hydrogeologic framework delineations and result in better groundwater-flow models. AEM data were acquired using the Resolve frequency-domain AEM system to map the Big Sioux aquifer in the region of the city of Sioux Falls. The survey acquired more than 870 line-kilometers of AEM data over a total area of about 145 square kilometers, primarily over the flood plain of the Big Sioux River between the cities of Dell Rapids and Sioux Falls. The U.S. Geological Survey inverted the survey data to generate resistivity-depth sections that were used in two-dimensional maps and in three-dimensional volumetric visualizations of the Earth resistivity distribution. Contact lines were drawn using a geographic information system to delineate interpreted geologic stratigraphy. The contact lines were converted to points and then interpolated into a raster surface. The methods used to develop elevation and depth maps of the hydrogeologic framework of the Big Sioux aquifer are described herein.The final AEM interpreted aquifer thickness ranged from 0 to 31 meters with an average thickness of 12.8 meters. The estimated total volume of the aquifer was 1,060,000,000 cubic meters based on the assumption that the top of the aquifer is the land-surface elevation. A simple calculation of the volume (length times width times height) of a previous delineation of the aquifer estimated the aquifer volume at 378,000,000 cubic meters; thus, the estimation based on AEM data is more than twice the previous estimate. The depth to top of Sioux Quartzite, which ranged in depth from 0 to 90 meters, also was delineated from the AEM data.

  4. An alternative arrangement of metered dosing fluid using centrifugal pump

    NASA Astrophysics Data System (ADS)

    Islam, Md. Arafat; Ehsan, Md.

    2017-06-01

    Positive displacement dosing pumps are extensively used in various types of process industries. They are widely used for metering small flow rates of a dosing fluid into a main flow. High head and low controllable flow rates make these pumps suitable for industrial flow metering applications. However their pulsating flow is not very suitable for proper mixing of fluids and they are relatively more expensive to buy and maintain. Considering such problems, alternative techniques to control the fluid flow from a low cost centrifugal pump is practiced. These include - throttling, variable speed drive, impeller geometry control and bypass control. Variable speed drive and impeller geometry control are comparatively costly and the flow control by throttling is not an energy efficient process. In this study an arrangement of metered dosing flow was developed using a typical low cost centrifugal pump using bypass flow technique. Using bypass flow control technique a wide range of metered dosing flows under a range of heads were attained using fixed pump geometry and drive speed. The bulk flow returning from the system into the main tank ensures better mixing which may eliminate the need of separate agitators. Comparative performance study was made between the bypass flow control arrangement of centrifugal pump and a diaphragm type dosing pump. Similar heads and flow rates were attainable using the bypass control system compared to the diaphragm dosing pump, but using relatively more energy. Geometrical optimization of the centrifugal pump impeller was further carried out to make the bypass flow arrangement more energy efficient. Although both the systems run at low overall efficiencies but the capital cost could be reduced by about 87% compared to the dosing pump. The savings in capital investment and lower maintenance cost very significantly exceeds the relatively higher energy cost of the bypass system. This technique can be used as a cost effective solution for industries in Bangladesh and have been implemented in two salt iodization plants at Narayangang.

  5. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sampling probe. (2) Exhaust flow metering system. A dilute exhaust flow metering system must be used to... exhaust. The background probe must draw a representative sample of the background air during each sampling... (bag) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe...

  6. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sampling probe. (2) Exhaust flow metering system. A dilute exhaust flow metering system must be used to... exhaust. The background probe must draw a representative sample of the background air during each sampling... (bag) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe...

  7. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sampling probe. (2) Exhaust flow metering system. A dilute exhaust flow metering system must be used to... exhaust. The background probe must draw a representative sample of the background air during each sampling... (bag) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe...

  8. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sampling probe. (2) Exhaust flow metering system. A dilute exhaust flow metering system must be used to... exhaust. The background probe must draw a representative sample of the background air during each sampling... (bag) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe...

  9. 40 CFR 90.420 - CVS concept of exhaust gas sampling system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sampling probe. (2) Exhaust flow metering system. A dilute exhaust flow metering system must be used to... exhaust. The background probe must draw a representative sample of the background air during each sampling... (bag) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe...

  10. Velocity profile survey in a 16-in. custody-transfer orifice meter for natural gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, J.J.S.

    1991-02-01

    This paper describes a research project conducted at Chevron U.S.A. Inc.'s Venice, LA, facility to ascertain that the flow condition inside a nominal 16-in. (406-mm) custody-transfer orifice meter was in compliance with American Gas Assn. (AGA) requirements. The survey was conducted at four flow rates ranging from 160 to 200 MMscf/D (4.53 {times} 10{sup 6} to 5.66 {times} 10{sup 6} std m{sup 3}/d) of processed natural gas at 880 psia (6.1 MPa). Experimental data were collected by a portable data-acquisition system driven by a lap-top microcomputer. The measured profiles indicated that the flow was nearly fully developed at the orificemore » plate location, and no significant swirling motion was detected. This test successfully demonstrated the techniques and equipment developed for determining actual flow distributions inside orifice meters in the field under normal operating conditions. This technology can be used to detect detrimental flow profiles and to verify compliance with AGA requirements on flow conditions in custody-transfer orifice meters.« less

  11. Novel Air Flow Meter for an Automobile Engine Using a Si Sensor with Porous Si Thermal Isolation

    PubMed Central

    Hourdakis, Emmanouel; Sarafis, Panagiotis; Nassiopoulou, Androula G.

    2012-01-01

    An air flow meter for measuring the intake air of an automobile engine is presented. It is based on a miniaturized silicon thermal mass flow sensor using a thick porous Si (Po-Si) layer for local thermal isolation from the Si substrate, on which the sensor active elements are integrated. The sensor is mounted on one side of a printed circuit board (PCB), on the other side of which the readout and control electronics of the meter are mounted. The PCB is fixed on a housing containing a semi-cylindrical flow tube, in the middle of which the sensor is situated. An important advantage of the present air flow meter is that it detects with equal sensitivity both forward and reverse flows. Two prototypes were fabricated, a laboratory prototype for flow calibration using mass flow controllers and a final demonstrator with the housing mounted in an automobile engine inlet tube. The final demonstrator was tested in real life conditions in the engine inlet tube of a truck. It shows an almost linear response in a large flow range between –6,500 kg/h and +6,500 kg/h, which is an order of magnitude larger than the ones usually encountered in an automobile engine. PMID:23202189

  12. Novel air flow meter for an automobile engine using a Si sensor with porous Si thermal isolation.

    PubMed

    Hourdakis, Emmanouel; Sarafis, Panagiotis; Nassiopoulou, Androula G

    2012-11-02

    An air flow meter for measuring the intake air of an automobile engine is presented. It is based on a miniaturized silicon thermal mass flow sensor using a thick porous Si (Po-Si) layer for local thermal isolation from the Si substrate, on which the sensor active elements are integrated. The sensor is mounted on one side of a printed circuit board (PCB), on the other side of which the readout and control electronics of the meter are mounted. The PCB is fixed on a housing containing a semi-cylindrical flow tube, in the middle of which the sensor is situated. An important advantage of the present air flow meter is that it detects with equal sensitivity both forward and reverse flows. Two prototypes were fabricated, a laboratory prototype for flow calibration using mass flow controllers and a final demonstrator with the housing mounted in an automobile engine inlet tube. The final demonstrator was tested in real life conditions in the engine inlet tube of a truck. It shows an almost linear response in a large flow range between –6,500 kg/h and +6,500 kg/h, which is an order of magnitude larger than the ones usually encountered in an automobile engine.

  13. 40 CFR 60.73a - Emissions testing and monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... system (e.g., weigh scale, volume flow meter, mass flow meter, tank volume) to measure and record the... via titration or by determining the temperature and specific gravity of the nitric acid. You may also...

  14. 40 CFR 60.73a - Emissions testing and monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... system (e.g., weigh scale, volume flow meter, mass flow meter, tank volume) to measure and record the... via titration or by determining the temperature and specific gravity of the nitric acid. You may also...

  15. Continuous flow measurements using fixed ultrasonic meters

    USGS Publications Warehouse

    Oltmann, Rick

    1993-01-01

    USGS has or soon will be installing four continuous flow-monitoring stations in the delta that will use ultrasonic velocity meters (DVM). Funding for the stations has been provided by USGS, DWR, USBR, and Contra Costa Water District.

  16. Postwildfire debris flows hazard assessment for the area burned by the 2011 Track Fire, northeastern New Mexico and southeastern Colorado

    USGS Publications Warehouse

    Tillery, Anne C.; Darr, Michael J.; Cannon, Susan H.; Michael, John A.

    2011-01-01

    In June 2011, the Track Fire burned 113 square kilometers in Colfax County, northeastern New Mexico, and Las Animas County, southeastern Colorado, including the upper watersheds of Chicorica and Raton Creeks. The burned landscape is now at risk of damage from postwildfire erosion, such as that caused by debris flows and flash floods. This report presents a preliminary hazard assessment of the debris-flow potential from basins burned by the Track Fire. A pair of empirical hazard-assessment models developed using data from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volume of debris flows at the outlets of selected drainage basins within the burned area. The models incorporate measures of burn severity, topography, soils, and storm rainfall to estimate the probability and volume of post-fire debris flows following the fire. In response to a design storm of 38 millimeters of rain in 30 minutes (10-year recurrence-interval), the probability of debris flow estimated for basins burned by the Track fire ranged between 2 and 97 percent, with probabilities greater than 80 percent identified for the majority of the tributary basins to Raton Creek in Railroad Canyon; six basins that flow into Lake Maloya, including the Segerstrom Creek and Swachheim Creek basins; two tributary basins to Sugarite Canyon, and an unnamed basin on the eastern flank of the burned area. Estimated debris-flow volumes ranged from 30 cubic meters to greater than 100,000 cubic meters. The largest volumes (greater than 100,000 cubic meters) were estimated for Segerstrom Creek and Swachheim Creek basins, which drain into Lake Maloya. The Combined Relative Debris-Flow Hazard Ranking identifies the Segerstrom Creek and Swachheim Creek basins as having the highest probability of producing the largest debris flows. This finding indicates the greatest post-fire debris-flow impacts may be expected to Lake Maloya. In addition, Interstate Highway 25, Raton Creek and the rail line in Railroad Canyon, County road A-27, and State Highway 526 in Sugarite Canyon may also be affected where they cross drainages downstream from recently burned basins. Although this assessment indicates that a rather large debris flow (approximately 42,000 cubic meters) may be generated from the basin above the City of Raton (basin 9) in response to the design storm, the probability of such an event is relatively low (approximately 10 percent). Additional assessment is necessary to determine if the estimated volume of material is sufficient to travel into the City of Raton. In addition, even small debris flows may affect structures at or downstream from basin outlets and increase the threat of flooding downstream by damaging or blocking flood mitigation structures. The maps presented here may be used to prioritize areas where erosion mitigation or other protective measures may be necessary within a 2- to 3-year window of vulnerability following the Track Fire.

  17. Biosensing of DNA oxidative damage: a model of using glucose meter for non-glucose biomarker detection.

    PubMed

    Zhu, Xuena; Sarwar, Mehenur; Yue, Qiaoli; Chen, Chunying; Li, Chen-Zhong

    2017-01-01

    Non-glucose biomarker-DNA oxidative damage biomarker 8-hydroxy-2'-deoxyguanosine (8-OHdG) has been successfully detected using a smartphone-enabled glucose meter. Through a series of immune reactions and enzymatic reactions on a solid lateral flow platform, 8-OHdG concentration has been converted to a relative amount of glucose, and therefore can be detected by conventional glucose meter directly. The device was able to detect 8-OHdG concentrations in phosphate buffer saline as low as 1.73 ng mL -1 with a dynamic range of 1-200 ng mL -1 . Considering the inherent advantages of the personal glucose meter, the demonstration of this device, therefore, should provide new opportunities for the monitoring of a wide range of biomarkers and various target analytes in connection with different molecular recognition events.

  18. Comparison of Surface Flow Features from Lidar-Derived Digital Elevation Models with Historical Elevation and Hydrography Data for Minnehaha County, South Dakota

    USGS Publications Warehouse

    Poppenga, Sandra K.; Worstell, Bruce B.; Stoker, Jason M.; Greenlee, Susan K.

    2009-01-01

    The U.S. Geological Survey (USGS) has taken the lead in the creation of a valuable remote sensing product by incorporating digital elevation models (DEMs) derived from Light Detection and Ranging (lidar) into the National Elevation Dataset (NED), the elevation layer of 'The National Map'. High-resolution lidar-derived DEMs provide the accuracy needed to systematically quantify and fully integrate surface flow including flow direction, flow accumulation, sinks, slope, and a dense drainage network. In 2008, 1-meter resolution lidar data were acquired in Minnehaha County, South Dakota. The acquisition was a collaborative effort between Minnehaha County, the city of Sioux Falls, and the USGS Earth Resources Observation and Science (EROS) Center. With the newly acquired lidar data, USGS scientists generated high-resolution DEMs and surface flow features. This report compares lidar-derived surface flow features in Minnehaha County to 30- and 10-meter elevation data previously incorporated in the NED and ancillary hydrography datasets. Surface flow features generated from lidar-derived DEMs are consistently integrated with elevation and are important in understanding surface-water movement to better detect surface-water runoff, flood inundation, and erosion. Many topographic and hydrologic applications will benefit from the increased availability of accurate, high-quality, and high-resolution surface-water data. The remotely sensed data provide topographic information and data integration capabilities needed for meeting current and future human and environmental needs.

  19. Microtopographic evolution of lava flows at Cima volcanic field, Mojave Desert, California

    NASA Technical Reports Server (NTRS)

    Farr, Tom G.

    1992-01-01

    Microtopographic profiles were measured and power spectra calculated for dated lava flow surfaces at Cima volcanic field in the eastern Mojave Desert of California in order to quantify changes in centimeter- to meter-scale roughness as a function of age. For lava flows younger than about 0.8 m.y., roughness over all spatial scales decreases with age, with meter-scale roughness decreasing slightly more than centimeter scales. Flows older than about 0.8 m.y. show a reversal of this trend, becoming as rough as young flows at these scales. Modeling indicates that eolian deposition can explain most of the change observed in the offset, or roughness amplitude, of power spectra of flow surface profiles up to 0.8 m.y. Other processes, such as rubbing and stone pavement development, appear to have a minor effect in this age range. Changes in power spectra of surfaces older than about 0.8 m.y. are consistent with roughening due to fluvial dissection. These results agree qualitatively with a process-response model that attributes systematic changes in flow surface morphology to cyclic changes in the rates of eolian, soil formation, and fluvial processes. Identification of active surficial processes and estimation of the extent of their effects, or stage of surficial evolution, through measurement of surface roughness will help put the correlation of surficial units on a quantitative basis. This may form the basis for the use of radar remote sensing data to help in regional correlations of surficial units.

  20. Ramp metering : procedure manual.

    DOT National Transportation Integrated Search

    2002-11-01

    Ramp metering is a traffic management tool used to increase the efficiency and safety of the : traffic operations on freeways. It is one of the most cost effective ways of managing traffic flow. : It improves traffic flow on congested freeways and of...

  1. Progress in catalytic ignition fabrication and modeling : fabrication part 2.

    DOT National Transportation Integrated Search

    2012-06-01

    The ignition temperature and heat generation from oxidation of methane on a platinum catalyst were : determined experimentally. A 127 micron diameter platinum coiled wire was placed crosswise in a : quartz tube of a plug flow reactor. A source meter ...

  2. Investigation of flow fields within large scale hypersonic inlet models

    NASA Technical Reports Server (NTRS)

    Gnos, A. V.; Watson, E. C.; Seebaugh, W. R.; Sanator, R. J.; Decarlo, J. P.

    1973-01-01

    Analytical and experimental investigations were conducted to determine the internal flow characteristics in model passages representative of hypersonic inlets for use at Mach numbers to about 12. The passages were large enough to permit measurements to be made in both the core flow and boundary layers. The analytical techniques for designing the internal contours and predicting the internal flow-field development accounted for coupling between the boundary layers and inviscid flow fields by means of a displacement-thickness correction. Three large-scale inlet models, each having a different internal compression ratio, were designed to provide high internal performance with an approximately uniform static-pressure distribution at the throat station. The models were tested in the Ames 3.5-Foot Hypersonic Wind Tunnel at a nominal free-stream Mach number of 7.4 and a unit free-stream Reynolds number of 8.86 X one million per meter.

  3. Postwildfire debris-flow hazard assessment of the area burned by the 2013 West Fork Fire Complex, southwestern Colorado

    USGS Publications Warehouse

    Verdin, Kristine L.; Dupree, Jean A.; Stevens, Michael R.

    2013-01-01

    This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2013 West Fork Fire Complex near South Fork in southwestern Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence, potential volume of debris flows, and the combined debris-flow hazard ranking along the drainage network within and just downstream from the burned area, and to estimate the same for 54 drainage basins of interest within the perimeter of the burned area. Input data for the debris-flow models included topographic variables, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall, referred to as a 2-year storm; (2) 10-year-recurrence, 1-hour-duration rainfall, referred to as a 10-year storm; and (3) 25-year-recurrence, 1-hour-duration rainfall, referred to as a 25-year storm. Estimated debris-flow probabilities at the pour points of the 54 drainage basins of interest ranged from less than 1 to 65 percent in response to the 2-year storm; from 1 to 77 percent in response to the 10-year storm; and from 1 to 83 percent in response to the 25-year storm. Twelve of the 54 drainage basins of interest have a 30-percent probability or greater of producing a debris flow in response to the 25-year storm. Estimated debris-flow volumes for all rainfalls modeled range from a low of 2,400 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages also were predicted to produce substantial debris flows. One of the 54 drainage basins of interest had the highest combined hazard ranking, while 9 other basins had the second highest combined hazard ranking. Of these 10 basins with the 2 highest combined hazard rankings, 7 basins had predicted debris-flow volumes exceeding 100,000 cubic meters, while 3 had predicted probabilities of debris flows exceeding 60 percent. The 10 basins with high combined hazard ranking include 3 tributaries in the headwaters of Trout Creek, four tributaries to the West Fork San Juan River, Hope Creek draining toward a county road on the eastern edge of the burn, Lake Fork draining to U.S. Highway 160, and Leopard Creek on the northern edge of the burn. The probabilities and volumes for the modeled storms indicate a potential for debris-flow impacts on structures, reservoirs, roads, bridges, and culverts located within and immediately downstream from the burned area. U.S. Highway 160, on the eastern edge of the burn area, also is susceptible to impacts from debris flows.

  4. From Magma Fracture to a Seismic Magma Flow Meter

    NASA Astrophysics Data System (ADS)

    Neuberg, J. W.

    2007-12-01

    Seismic swarms of low-frequency events occur during periods of enhanced volcanic activity and have been related to the flow of magma at depth. Often they precede a dome collapse on volcanoes like Soufriere Hills, Montserrat, or Mt St Helens. This contribution is based on the conceptual model of magma rupture as a trigger mechanism. Several source mechanisms and radiation patterns at the focus of a single event are discussed. We investigate the accelerating event rate and seismic amplitudes during one swarm, as well as over a time period of several swarms. The seismic slip vector will be linked to magma flow parameters resulting in estimates of magma flux for a variety of flow models such as plug flow, parabolic- or friction controlled flow. In this way we try to relate conceptual models to quantitative estimations which could lead to estimations of magma flux at depth from seismic low-frequency signals.

  5. Field calibration of orifice meters for natural gas flow

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ting, V.C.; Shen, J.J.S.

    1989-03-01

    This paper presents the orifice calibration results for nominal 15.24, 10.16, and 5.08-cm (6,4,2-in.) orifice meters conducted at the Chevron's Sand Hills natural gas flow measurement facility in Crane, Texas. Over 200 test runs were collected in a field environment to study the accuracy of the orifice meters. Data were obtained at beta ratios ranging from 0.12 to 0.74 at the nominal conditions of 4576 kPa and 27{sup 0}C (650 psig and 80{sup 0}F) with a 0.57 specific gravity processed, pipeline quality natural gas. A bank of critical flow nozzles was used as the flow rate proving device to calibratemore » the orifice meters. Orifice discharge coefficients were computed with ANSI/API 2530-1985 (AGA3) and ISO 5167/ASME MFC-3M-1984 equations for every set of data points. With the orifice bore Reynolds numbers ranging from 1 to 9 million, the Sand Hills calibration data bridge the gap between the Ohio State water data at low Reynolds numbers and Chevron's high Reynolds number test data taken at a large test facility in Venice, Louisiana. The test results also successfully demonstrate that orifice meters can be accurately proved with critical flow nozzles under realistic field conditions.« less

  6. Support of gas flowmeter upgrade

    NASA Technical Reports Server (NTRS)

    Waugaman, Dennis

    1996-01-01

    A project history review, literature review, and vendor search were conducted to identify a flowmeter that would improve the accuracy of gaseous flow measurements in the White Sands Test Facility (WSTF) Calibration Laboratory and the Hydrogen High Flow Facility. Both facilities currently use sonic flow nozzles to measure flowrates. The flow nozzle pressure drops combined with corresponding pressure and temperature measurements have been estimated to produce uncertainties in flowrate measurements of 2 to 5 percent. This study investigated the state of flowmeter technology to make recommendations that would reduce those uncertainties. Most flowmeters measure velocity and volume, therefore mass flow measurement must be calculated based on additional pressures and temperature measurement which contribute to the error. The two exceptions are thermal dispersion meters and Coriolis mass flowmeters. The thermal dispersion meters are accurate to 1 to 5 percent. The Coriolis meters are significantly more accurate, at least for liquids. For gases, there is evidence they may be accurate to within 0.5 percent or better of the flowrate, but there may be limitations due to inappropriate velocity, pressure, Mach number and vibration disturbances. In this report, a comparison of flowmeters is presented. Candidate Coriolis meters and a methodology to qualify the meter with tests both at WSTF and Southwest Research Institute are recommended and outlined.

  7. Development and testing of highway storm-sewer flow measurement and recording system

    USGS Publications Warehouse

    Kilpatrick, F.A.; Kaehrle, W.R.; Hardee, Jack; Cordes, E.H.; Landers, M.N.

    1985-01-01

    A comprehensive study and development of measuring instruments and techniques for measuring all components of flow in a storm-sewer drainage system was undertaken by the U.S. Geological Survey under the sponsorship of the Federal Highway Administration. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, electromagnetic velocity meters as well as the development and calibration of pneumatic-bubbler pressure transducer head measuring systems. Tracer-dilution and acoustic flow meter measurements were used in field verification tests. A single micrologger was used to record data from all the above instruments as well as from a tipping-bucket rain gage and also to activate on command the electromagnetic velocity meter and tracer-dilution systems. (Author 's abstract)

  8. Theoretical analysis of an oscillatory plane Poiseuille flow—A link to the design of vortex flow meter

    NASA Astrophysics Data System (ADS)

    Ma, Huai-Lung; Kuo, Cheng-Hsiung

    2017-05-01

    Theoretical analysis on an oscillatory plane Poiseuille flow is conducted in terms of a non-dimensional ratio (η) of the channel half-width to Stokes' layer thickness. The cyclic velocity profiles, the phase shifts and the magnitudes among the driving pressure gradient, the induced wall shear stress, and the volume flux are investigated. Also, the flow physics at a different ratio η is demonstrated. In this study, the mechanism of the driving pressure gradient and the oscillating volume flux is similar to and can be employed to demonstrate the slit flow in the application of the novel vortex flow meter using a slit cylinder as a shedder. When applied to the novel vortex flow meter, the non-dimensional ratio η can be expressed as the relation of the slit width ratio (S/D), the Strouhal number, and the Reynolds number. Finally, a range of η between 0.97 < η < 20 will be suggested for the vortex flow meter at the design stage. Large values of η are employed at a high Reynolds number, and small η is used for low Reynolds number applications. In the novel vortex flow meters, a cylinder with a normal axial slit of width (S) is employed as the shedder. Due to the primary lock-on, the process of vortex shedding synchronizes with the rhythm of slit flow leading to a stable shedding frequency. The value η is well correlated by the value of ηopt obtained by experiments and shows a one-to-one correspondence to the slit ratio at each Reynolds number. Once the design value of ηopt is determined, the optimal slit ratio can be estimated for a fixed applied Reynolds number at the design stage.

  9. The sand seas of titan: Cassini RADAR observations of longitudinal dunes

    USGS Publications Warehouse

    Lorenz, R.D.; Wall, S.; Radebaugh, J.; Boubin, G.; Reffet, E.; Janssen, M.; Stofan, E.; Lopes, R.; Kirk, R.; Elachi, C.; Lunine, J.; Mitchell, Ken; Paganelli, F.; Soderblom, L.; Wood, C.; Wye, L.; Zebker, H.; Anderson, Y.; Ostro, S.; Allison, M.; Boehmer, R.; Callahan, P.; Encrenaz, P.; Ori, G.G.; Francescetti, G.; Gim, Y.; Hamilton, G.; Hensley, S.; Johnson, W.; Kelleher, K.; Muhleman, D.; Picardi, G.; Posa, F.; Roth, L.; Seu, R.; Shaffer, S.; Stiles, B.; Vetrella, S.; Flamini, E.; West, R.

    2006-01-01

    The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show ???100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of ???0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps.

  10. The sand seas of Titan: Cassini RADAR observations of longitudinal dunes.

    PubMed

    Lorenz, R D; Wall, S; Radebaugh, J; Boubin, G; Reffet, E; Janssen, M; Stofan, E; Lopes, R; Kirk, R; Elachi, C; Lunine, J; Mitchell, K; Paganelli, F; Soderblom, L; Wood, C; Wye, L; Zebker, H; Anderson, Y; Ostro, S; Allison, M; Boehmer, R; Callahan, P; Encrenaz, P; Ori, G G; Francescetti, G; Gim, Y; Hamilton, G; Hensley, S; Johnson, W; Kelleher, K; Muhleman, D; Picardi, G; Posa, F; Roth, L; Seu, R; Shaffer, S; Stiles, B; Vetrella, S; Flamini, E; West, R

    2006-05-05

    The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show approximately 100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of approximately 0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps.

  11. Water balance in irrigation districts. Uncertainty in on-demand pressurized networks

    NASA Astrophysics Data System (ADS)

    Sánchez-Calvo, Raúl; Rodríguez-Sinobas, Leonor; Juana, Luis; Laguna, Francisco Vicente

    2015-04-01

    In on-demand pressurized irrigation distribution networks, applied water volume is usually controlled opening a valve during a calculated time interval, and assuming constant flow rate. In general, pressure regulating devices for controlling the discharged flow rate by irrigation units are needed due to the variability of pressure conditions. A pressure regulating valve PRV is the commonly used pressure regulating device in a hydrant, which, also, executes the open and close function. A hydrant feeds several irrigation units, requiring a wide range in flow rate. In addition, some flow meters are also available, one as a component of the hydrant and the rest are placed downstream. Every land owner has one flow meter for each group of field plots downstream the hydrant. Ideal PRV performance would maintain a constant downstream pressure. However, the true performance depends on both upstream pressure and the discharged flow rate. Theoretical flow rates values have been introduced into a PRV behavioral model, validated in laboratory, coupled with an on-demand irrigation district waterworks, composed by a distribution network and a multi-pump station. Variations on flow rate are simulated by taking into account the consequences of variations on climate conditions and also decisions in irrigation operation, such us duration and frequency application. The model comprises continuity, dynamic and energy equations of the components of both the PRV and the water distribution network. In this work the estimation of water balance terms during the irrigation events in an irrigation campaign has been simulated. The effect of demand concentration peaks has been estimated.

  12. Direct Methanol Fuel Cell (DMFC) Battery Replacement Program

    DTIC Science & Technology

    2013-01-29

    selection of the Reynold’s number enables use of water for simulation of gas or liquid flow. Introduction of dye to the flow stream, with video...calibrated using a soap -film flow meter (Bubble-o-meter, Dublin, OH). Eleven Array system temperature regions were set as follows prior to start of...expected. The ar- ray flow proceeds down the columns: column effects would be more likely than row effects from a design of experiments perspective

  13. Calibration and application of an automated seepage meter for monitoring water flow across the sediment-water interface.

    PubMed

    Zhu, Tengyi; Fu, Dafang; Jenkinson, Byron; Jafvert, Chad T

    2015-04-01

    The advective flow of sediment pore water is an important parameter for understanding natural geochemical processes within lake, river, wetland, and marine sediments and also for properly designing permeable remedial sediment caps placed over contaminated sediments. Automated heat pulse seepage meters can be used to measure the vertical component of sediment pore water flow (i.e., vertical Darcy velocity); however, little information on meter calibration as a function of ambient water temperature exists in the literature. As a result, a method with associated equations for calibrating a heat pulse seepage meter as a function of ambient water temperature is fully described in this paper. Results of meter calibration over the temperature range 7.5 to 21.2 °C indicate that errors in accuracy are significant if proper temperature-dependence calibration is not performed. The proposed calibration method allows for temperature corrections to be made automatically in the field at any ambient water temperature. The significance of these corrections is discussed.

  14. Investigation of Seepage Meter Measurements in Steady Flow and Wave Conditions.

    PubMed

    Russoniello, Christopher J; Michael, Holly A

    2015-01-01

    Water exchange between surface water and groundwater can modulate or generate ecologically important fluxes of solutes across the sediment-water interface. Seepage meters can directly measure fluid flux, but mechanical resistance and surface water dynamics may lead to inaccurate measurements. Tank experiments were conducted to determine effects of mechanical resistance on measurement efficiency and occurrence of directional asymmetry that could lead to erroneous net flux measurements. Seepage meter efficiency was high (average of 93%) and consistent for inflow and outflow under steady flow conditions. Wave effects on seepage meter measurements were investigated in a wave flume. Seepage meter net flux measurements averaged 0.08 cm/h-greater than the expected net-zero flux, but significantly less than theoretical wave-driven unidirectional discharge or recharge. Calculations of unidirectional flux from pressure measurements (Darcy flux) and theory matched well for a ratio of wave length to water depth less than 5, but not when this ratio was greater. Both were higher than seepage meter measurements of unidirectional flux made with one-way valves. Discharge averaged 23% greater than recharge in both seepage meter measurements and Darcy calculations of unidirectional flux. Removal of the collection bag reduced this net discharge. The presence of a seepage meter reduced the amplitude of pressure signals at the bed and resulted in a nearly uniform pressure distribution beneath the seepage meter. These results show that seepage meters may provide accurate measurements of both discharge and recharge under steady flow conditions and illustrate the potential measurement errors associated with dynamic wave environments. © 2014, National Ground Water Association.

  15. Non-invasive energy meter for fixed and variable flow systems

    DOEpatents

    Menicucci, David F.; Black, Billy D.

    2005-11-01

    An energy metering method and apparatus for liquid flow systems comprising first and second segments of one or more conduits through which a liquid flows, comprising: attaching a first temperature sensor for connection to an outside of the first conduit segment; attaching a second temperature sensor for connection to an outside of the second conduit segment; via a programmable control unit, receiving data from the sensors and calculating energy data therefrom; and communicating energy data from the meter; whereby the method and apparatus operate without need to temporarily disconnect or alter the first or second conduit segments. The invention operates with both variable and fixed flow systems, and is especially useful for both active and passive solar energy systems.

  16. Velocity profile, water-surface slope, and bed-material size for selected streams in Colorado

    USGS Publications Warehouse

    Marchand, J.P.; Jarrett, R.D.; Jones, L.L.

    1984-01-01

    Existing methods for determining the mean velocity in a vertical sampling section do not address the conditions present in high-gradient, shallow-depth streams common to mountainous regions such as Colorado. The report presents velocity-profile data that were collected for 11 streamflow-gaging stations in Colorado using both a standard Price type AA current meter and a prototype Price Model PAA current meter. Computational results are compiled that will enable mean velocities calculated from measurements by the two current meters to be compared with each other and with existing methods for determining mean velocity. Water-surface slope, bed-material size, and flow-characteristic data for the 11 sites studied also are presented. (USGS)

  17. Fabrication and evaluation of a graphene oxide-based cantilever-type flow-meter for subsonic gas flow rate measurement

    NASA Astrophysics Data System (ADS)

    Hamdollahi, Hassan; Rahbar-Shahrouzi, Javad

    2018-05-01

    In this paper, a cantilever-type flow meter was fabricated to measure the rate of air flow in turbulent subsonic regimes such as purged gases. In the fabrication process, a piezoresistive material was coated on an interdigitated electric board as a substrate. The piezoresistive layer was a blend of latex as the polymeric matrix and graphene oxide as the sensing nanomaterial agent, which was reduced by solvothermal reduction method. The piezoresistive blend was dip-coated on a substrate with dotted pattern and was then reduced at 240 °C for 1 h in every coating step. When an air flow passed over the surface of the cantilever beam, the beam was bent in the downward direction, resulting in small variations in the resistance of the piezoresistive layer and a change in the bending angle of the cantilever which were measured simultaneously. The air flow rate was acquired via calibrating electrical resistance changes by Arduino and Wheatstone bridge circuit. The blending angle of the substrate caused by the interaction between the airflow and the cantilever and recorded by the camera and image processing was ultimately compared with the simulation results. The flow meter accuracy as a percentage of full scale (% FS) was calculated to be  ±5.8%, and mean deviation was equal to 2.1 (% FS) with the appropriate response time of 0.70 s at the air flow range of 100‑240 m s‑1. Highlights • A cantilever-type flow meter was fabricated to measure the high-speed air flow rate. • The sensitive piezoresistive material was composed of GO and latex. • The dip-coating method was used to deposit the piezoresistive layer on the fiberglass substrate. • The impact of effective parameters on the performance of the flow meter was investigated. • A simulation study was performed and the results were compared with the experimental data.

  18. Deep and intermediate mediterranean water in the western Alboran Sea

    NASA Astrophysics Data System (ADS)

    Parrilla, Gregorio; Kinder, Thomas H.; Preller, Ruth H.

    1986-01-01

    Hydrographic and current meter data, obtained during June to October 1982, and numerical model experiments are used to study the distribution and flow of Mediterranean waters in the western Alboran Sea. The Intermediate Water is more pronounced in the northern three-fourths of the sea, but its distribution is patchy as manifested by variability of the temperature and salinity maxima at scales ≤10 km. Current meters in the lower Intermediate Water showed mean flow toward the Strait at 2 cm s -1. A reversal of this flow lasted about 2 weeks. A rough estimate of the mean westward Intermediate Water transport was 0.4 × 10 6 m 3 s -1, about one-third of the total outflow, so that the best estimates of the contributions of traditionally defined Intermediate Water and Deep Water account for only about one-half of the total outflow. The Deep Water was uplifted against the southern continental slope from Alboran Island (3°W) to the Strait. There was also a similar but much weaker banking against the Spanish slope, but a deep current record showed that the eastward recirculation implied by this banking is probably intermittent. Two-layer numerical model experiments simulated the Intermediate Water flow with a flat bottom and the Deep Water with realistic bottom topography. Both experiments replicated the major circulation features, and the Intermediate Water flow was concentrated in the north because of rotation and the Deep Water flow in the south because of topographic control.

  19. Fuel cell membrane hydration and fluid metering

    DOEpatents

    Jones, Daniel O.; Walsh, Michael M.

    1999-01-01

    A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel in order to mix its respective portion of liquid water with the corresponding portion of the stream. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).

  20. Comparison of continuum and particle simulations of expanding rarefied flows

    NASA Technical Reports Server (NTRS)

    Lumpkin, Forrest E., III; Boyd, Iain D.; Venkatapathy, Ethiraj

    1993-01-01

    Comparisons of Navier-Stokes solutions and particle simulations for a simple two-dimensional model problem at a succession of altitudes are performed in order to assess the importance of rarefaction effects on the base flow region. In addition, an attempt is made to include 'Burnett-type' extensions to the Navier-Stokes constitutive relations. The model geometry consists of a simple blunted wedge with a 0.425 meter nose radius, a 70 deg cone half angle, a 1.7 meter base length, and a rounded shoulder. The working gas is monatomic with a molecular weight and viscosity similar to air and was chosen to focus the study on the continuum and particle methodologies rather than the implementation of thermo-chemical modeling. Three cases are investigated, all at Mach 29, with densities corresponding to altitudes of 92 km, 99 km, and 105 km. At the lowest altitude, Navier-Stokes solutions agree well with particle simulations. At the higher altitudes, the Navier-Stokes equations become less accurate. In particular, the Navier-Stokes equations and particle method predict substantially different flow turning angle in the wake near the after body. Attempts to achieve steady continuum solutions including 'Burnett-type' terms failed. Further research is required to determine whether the boundary conditions, the equations themselves, or other unknown causes led to this failure.

  1. Monitoring of multiphase flows for superconducting accelerators and others applications

    NASA Astrophysics Data System (ADS)

    Filippov, Yu. P.; Kakorin, I. D.; Kovrizhnykh, A. M.; Miklayev, V. M.

    2017-07-01

    This paper is a review on implementation of measuring systems for two-phase helium, hydrogen, liquefied natural gas (LNG), and oil-formation/salty water flows. Two types of such systems are presented. The first type is based on two-phase flow-meters combining void fraction radio-frequency (RF) sensors and narrowing devices. They can be applied for superconducting accelerators cooled with two-phase helium, refueling hydrogen system for space ships and some applications in oil production industry. The second one is based on combination of a gamma-densitometer and a narrowing device. These systems can be used to monitor large two-phase LNG and oil-formation water flows. An electronics system based on a modular industrial computer is described as well. The metrological characteristics for different flow-meters are presented and the obtained results are discussed. It is also shown that the experience gained allows separationless flow-meter for three-phase oil-gas-formation water flows to be produced.

  2. USE OF ELECTRICAL RESISTIVITY PROBE FOR DETERMINATION OF HYPORHEIC FLOW

    EPA Science Inventory

    The hyporheic zone can play a significant role in nutrient behavior in watersheds. Conceptual models describe the behavior of nutrients and biota for the hyporheic ecotone, but site characterization is needed to quantiiy effects at the restoration reach scale (hundreds of meters)...

  3. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1999-02-02

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  4. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1990-01-01

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  5. A synchronous strobed laser light sheet for helicopter model rotor flow visualization

    NASA Technical Reports Server (NTRS)

    Leighty, Bradley D.; Rhodes, David B.; Jones, Stephen B.; Franke, John M.

    1990-01-01

    A synchronous, strobed laser light sheet has been developed for use in flow visualization of a helicopter rotor model. The light sheet strobe circuit included selectable blade position, strobe duration, and multiple pulses per revolution for rotors having 2 to 9 blades. The flow was seeded with propylene glycol. Between runs, a calibration grid board was placed in the plane of the laser sheet and recorded with the video camera at the position used to record the flow field. A slip-sync mode permitted slow motion visualization of the flow field over complete rotations of the rotor. The system was used to make two-dimensional flow field cuts of a four-bladed rotor operating at advance ratio of 0.37 at wind tunnel speeds up to 79.25 meters per second (260 feet per second).

  6. Test Your Asthma Knowledge

    MedlinePlus

    ... be eliminated simply by washing sheets in warm water. True or False? A peak flow meter records how many asthma attacks you have had. ... degrees or less, and by washing items in water temperatures of 130 degrees or ... them. False: Peak flow meters measure how well air moves out of your ...

  7. Insert metering plates for gas turbine nozzles

    DOEpatents

    Burdgick, Steven S.; Itzel, Gary; Chopra, Sanjay; Abuaf, Nesim; Correia, Victor H.

    2004-05-11

    The invention comprises a metering plate which is assembled to an impingement insert for use in the nozzle of a gas turbine. The metering plate can have one or more metering holes and is used to balance the cooling flow within the nozzle. A metering plate with multiple holes reduces static pressure variations which result from the cooling airflow through the metering plate. The metering plate can be assembled to the insert before or after the insert is inserted into the nozzle.

  8. Two-Phase flow instrumentation for nuclear accidents simulation

    NASA Astrophysics Data System (ADS)

    Monni, G.; De Salve, M.; Panella, B.

    2014-11-01

    The paper presents the research work performed at the Energy Department of the Politecnico di Torino, concerning the development of two-phase flow instrumentation and of models, based on the analysis of experimental data, that are able to interpret the measurement signals. The study has been performed with particular reference to the design of power plants, such as nuclear water reactors, where the two-phase flow thermal fluid dynamics must be accurately modeled and predicted. In two-phase flow typically a set of different measurement instruments (Spool Piece - SP) must be installed in order to evaluate the mass flow rate of the phases in a large range of flow conditions (flow patterns, pressures and temperatures); moreover, an interpretative model of the SP need to be developed and experimentally verified. The investigated meters are: Turbine, Venturi, Impedance Probes, Concave sensors, Wire mesh sensor, Electrical Capacitance Probe. Different instrument combinations have been tested, and the performance of each one has been analyzed.

  9. James Webb Space Telescope Integrated Science Instrument Module Calibration and Verification of High-Accuracy Instrumentation to Measure Heat Flow in Cryogenic Testing

    NASA Technical Reports Server (NTRS)

    Comber, Brian; Glazer, Stuart

    2012-01-01

    The James Webb Space Telescope (JWST) is an upcoming flagship observatory mission scheduled to be launched in 2018. Three of the four science instruments are passively cooled to their operational temperature range of 36K to 40K, and the fourth instrument is actively cooled to its operational temperature of approximately 6K. The requirement for multiple thermal zoned results in the instruments being thermally connected to five external radiators via individual high purity aluminum heat straps. Thermal-vacuum and thermal balance testing of the flight instruments at the Integrated Science Instrument Module (ISIM) element level will take place within a newly constructed shroud cooled by gaseous helium inside Goddard Space Flight Center's (GSFC) Space environment Simulator (SES). The flight external radiators are not available during ISIM-level thermal vacuum/thermal testing, so they will be replaced in test with stable and adjustable thermal boundaries with identical physical interfaces to the flight radiators. Those boundaries are provided by specially designed test hardware which also measures the heat flow within each of the five heat straps to an accuracy of less than 2 mW, which is less than 5% of the minimum predicted heat flow values. Measurement of the heat loads to this accuracy is essential to ISIM thermal model correlation, since thermal models are more accurately correlated when temperature data is supplemented by accurate knowledge of heat flows. It also provides direct verification by test of several high-level thermal requirements. Devices that measure heat flow in this manner have historically been referred to a "Q-meters". Perhaps the most important feature of the design of the JWST Q-meters is that it does not depend on the absolute accuracy of its temperature sensors, but rather on knowledge of precise heater power required to maintain a constant temperature difference between sensors on two stages, for which a table is empirically developed during a calibration campaign in a small chamber at GSFC. This paper provides a brief review of Q-meter design, and discusses the Q-meter calibration procedure including calibration chamber modifications and accommodations, handling of differing conditions between calibration and usage, the calibration process itself, and the results of the tests used to determine if the calibration is successful.

  10. Method to produce American Thoracic Society flow-time waveforms using a mechanical pump.

    PubMed

    Hankinson, J L; Reynolds, J S; Das, M K; Viola, J O

    1997-03-01

    The American Thoracic Society (ATS) recently adopted a new set of 26 standard flow-time waveforms for use in testing both diagnostic and monitoring devices. Some of these waveforms have a higher frequency content than present in the ATS-24 standard volume-time waveforms, which, when produced by a mechanical pump, may result in a pump flow output that is less than the desired flow due to gas compression losses within the pump. To investigate the effects of gas compression, a mechanical pump was used to generate the necessary flows to test mini-Wright and Assess peak expiratory flow (PEF) meters. Flow output from the pump was measured by two different independent methods, a pneumotachometer and a method based on piston displacement and pressure measured within the pump. Measuring output flow based on piston displacement and pressure has been validated using a pneumotachometer and mini-Wright PEF meter, and found to accurately measure pump output. This method introduces less resistance (lower back-pressure) and dead space volume than using a pneumotachometer in series with the meter under test. Pump output flow was found to be lower than the desired flow both with the mini-Wright and Assess meters (for waveform No. 26, PEFs 7.1 and 10.9% lower, respectively). To compensate for losses due to gas compression, we have developed a method of deriving new input waveforms, which, when used to drive a commercially available mechanical pump, accurately and reliably produces the 26 ATS flow-time waveforms, even those with the fastest rise-times.

  11. An Experimental Device for Generating High Frequency Perturbations in Supersonic Wind Tunnels

    NASA Technical Reports Server (NTRS)

    Melcher, Kevin J.; Ibrahim, Mounir B.

    1996-01-01

    This paper describes the analytical study of a device that has been proposed as a mechanism for generating gust-like perturbations in supersonic wind tunnels. The device is envisioned as a means to experimentally validate dynamic models and control systems designed for high-speed inlets. The proposed gust generator is composed of two flat trapezoidal plates that modify the properties of the flow ingested by the inlet. One plate may be oscillated to generate small perturbations in the flow. The other plate is held stationary to maintain a constant angle-of-attack. Using an idealized approach, design equations and performance maps for the new device were developed from the compressible flow relations. A two-dimensional CFD code was used to confirm the correctness of these results. The idealized approach was then used to design and evaluate a new gust generator for a 3.05-meter by 3.05-meter (10-foot by 10-foot) supersonic wind tunnel.

  12. Electromagnetic Flow Meter Having a Driver Circuit Including a Current Transducer

    NASA Technical Reports Server (NTRS)

    Patel, Sandeep K. (Inventor); Karon, David M. (Inventor); Cushing, Vincent (Inventor)

    2014-01-01

    An electromagnetic flow meter (EMFM) accurately measures both the complete flow rate and the dynamically fluctuating flow rate of a fluid by applying a unipolar DC voltage to excitation coils for a predetermined period of time, measuring the electric potential at a pair of electrodes, determining a complete flow rate and independently measuring the dynamic flow rate during the "on" cycle of the DC excitation, and correcting the measurements for errors resulting from galvanic drift and other effects on the electric potential. The EMFM can also correct for effects from the excitation circuit induced during operation of the EMFM.

  13. Ultrasonic Blood Flow Measurement in Haemodialysis

    PubMed Central

    Sampson, D.; Papadimitriou, M.; Kulatilake, A. E.

    1970-01-01

    A 5-megacycle Doppler flow meter, calibrated in-vitro, was found to give a linear response to blood flow in the ranges commonly encountered in haemodialysis. With this, blood flow through artificial kidneys could be measured simply and with a clinically acceptable error. The method is safe, as blood lines do not have to be punctured or disconnected and hence there is no risk of introducing infection. Besides its value as a research tool the flow meter is useful in evaluating new artificial kidneys. Suitably modified it could form the basis of an arterial flow alarm system. PMID:5416812

  14. Comparison of five portable peak flow meters.

    PubMed

    Takara, Glaucia Nency; Ruas, Gualberto; Pessoa, Bruna Varanda; Jamami, Luciana Kawakami; Di Lorenzo, Valéria Amorim Pires; Jamami, Mauricio

    2010-05-01

    To compare the measurements of spirometric peak expiratory flow (PEF) from five different PEF meters and to determine if their values are in agreement. Inaccurate equipment may result in incorrect diagnoses of asthma and inappropriate treatments. Sixty-eight healthy, sedentary and insufficiently active subjects, aged from 19 to 40 years, performed PEF measurements using Air Zone, Assess, Galemed, Personal Best and Vitalograph peak flow meters. The highest value recorded for each subject for each device was compared to the corresponding spirometric values using Friedman's test with Dunn's post-hoc (p<0.05), Spearman's correlation test and Bland-Altman's agreement test. The median and interquartile ranges for the spirometric values and the Air Zone, Assess, Galemed, Personal Best and Vitalograph meters were 428 (263-688 L/min), 450 (350-800 L/min), 420 (310-720 L/min), 380 (300-735 L/min), 400 (310-685 L/min) and 415 (335-610 L/min), respectively. Significant differences were found when the spirometric values were compared to those recorded by the Air Zone(R) (p<0.001) and Galemed (p<0.01) meters. There was no agreement between the spirometric values and the five PEF meters. The results suggest that the values recorded from Galemed meters may underestimate the actual value, which could lead to unnecessary interventions, and that Air Zone meters overestimate spirometric values, which could obfuscate the need for intervention. These findings must be taken into account when interpreting both devices' results in younger people. These differences should also be considered when directly comparing values from different types of PEF meters.

  15. USE OF ELECTRICAL RESISTIVITY PROBE WITH MODFLOW FOR SCREENING LEVEL DETERMINATION OF PARAFLUVIAL HYPORHEIC FLOW

    EPA Science Inventory

    The hyporheic zone can provide significant nutrient attenuation in watersheds. Conceptual models describe the behavior of nutrients and biota for the hyporheic ecotone, but site characterization is needed to quantify these effects at the restoration reach scale (hundreds of meter...

  16. Twin Cities ramp meter evaluation : executive summary

    DOT National Transportation Integrated Search

    2001-02-01

    This report details the results of a study on the traffic flow and safety impacts of ramp metering. The study served two important public purposes. 1. It thoroughly documented the benefits resulting from ramp metering to traffic operations and relate...

  17. Remote sensing evidence of lava-ground ice interactions associated with the Lost Jim Lava Flow, Seward Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Marcucci, Emma C.; Hamilton, Christopher W.; Herrick, Robert R.

    2017-12-01

    Thermokarst terrains develop when ice-bearing permafrost melts and causes the overlying surface to subside or collapse. This process occurs widely throughout Arctic regions due to environmental and climatological factors, but can also be induced by localized melting of ground ice by active lava flows. The Lost Jim Lava Flow (LJLF) on the Seward Peninsula of Alaska provides evidence of former lava-ground ice interactions. Associated geomorphic features, on the scale of meters to tens of meters, were identified using satellite orthoimages and stereo-derived digital terrain models. The flow exhibits positive- and mixed-relief features, including tumuli ( N = 26) and shatter rings ( N = 4), as well as negative-relief features, such as lava tube skylights ( N = 100) and irregularly shaped topographic depressions ( N = 1188) that are interpreted to include lava-rise pits and lava-induced thermokarst terrain. Along the margins of the flow, there are also clusters of small peripheral pits that may be the products of meltwater or steam escape. On Mars, we observed morphologically similar pits near lava flow margins in northeastern Elysium Planitia, which suggests a common formation mechanism. Investigating the LJLF may therefore help to elucidate processes of lava-ground ice interaction on both Earth and Mars.

  18. Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

    NASA Astrophysics Data System (ADS)

    Hoffmann, D.; Willmann, A.; Göpfert, R.; Becker, P.; Folkmer, B.; Manoli, Y.

    2013-12-01

    In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced.

  19. Uncertainty and Traceability for the CEESI Iowa Natural Gas Facility.

    PubMed

    Johnson, Aaron; Kegel, Tom

    2004-01-01

    This paper analyzes the uncertainty of a secondary flow measurement facility that calibrates a significant fraction of United States and foreign flow meters used for custody transfer of natural gas. The facility, owned by the Colorado Experimental Engineering Station Incorporated (CEESI), is located in Iowa. This facility measures flow with nine turbine meter standards, each of which is traceable to the NIST primary flow standard. The flow capacity of this facility ranges from 0.7 actual m(3)/s to 10.7 actual m(3)/s at nominal pressures of 7174 kPa and at ambient temperatures. Over this flow range the relative expanded flow uncertainty varies from 0.28 % to 0.30 % (depending on flow).

  20. Public Sector Benefits From Aerospace Research and Development

    ERIC Educational Resources Information Center

    Hamilton, Jeffrey T.

    1973-01-01

    Many benefits from aerospace research have occurred: research on quiet aircraft engines, worldwide news coverage, contributions to the national economy, development of reliable fluid amplifiers and logic systems, attempts to control airport congestion, a low speed air sensor for use on a pulmonary flow meter and even as a flow meter in a large…

  1. On the Representation of Subgrid Microtopography Effects in Process-based Hydrologic Models

    NASA Astrophysics Data System (ADS)

    Jan, A.; Painter, S. L.; Coon, E. T.

    2017-12-01

    Increased availability of high-resolution digital elevation are enabling process-based hydrologic modeling on finer and finer scales. However, spatial variability in surface elevation (microtopography) exists below the scale of a typical hyper-resolution grid cell and has the potential to play a significant role in water retention, runoff, and surface/subsurface interactions. Though the concept of microtopographic features (depressions, obstructions) and the associated implications on flow and discharge are well established, representing those effects in watershed-scale integrated surface/subsurface hydrology models remains a challenge. Using the complex and coupled hydrologic environment of the Arctic polygonal tundra as an example, we study the effects of submeter topography and present a subgrid model parameterized by small-scale spatial heterogeneities for use in hyper-resolution models with polygons at a scale of 15-20 meters forming the surface cells. The subgrid model alters the flow and storage terms in the diffusion wave equation for surface flow. We compare our results against sub-meter scale simulations (acts as a benchmark for our simulations) and hyper-resolution models without the subgrid representation. The initiation of runoff in the fine-scale simulations is delayed and the recession curve is slowed relative to simulated runoff using the hyper-resolution model with no subgrid representation. Our subgrid modeling approach improves the representation of runoff and water retention relative to models that ignore subgrid topography. We evaluate different strategies for parameterizing subgrid model and present a classification-based method to efficiently move forward to larger landscapes. This work was supported by the Interoperable Design of Extreme-scale Application Software (IDEAS) project and the Next-Generation Ecosystem Experiments-Arctic (NGEE Arctic) project. NGEE-Arctic is supported by the Office of Biological and Environmental Research in the DOE Office of Science.

  2. Potential climate-induced runoff changes and associated uncertainty in four Pacific Northwest estuaries

    USGS Publications Warehouse

    Steele, Madeline O.; Chang, Heejun; Reusser, Deborah A.; Brown, Cheryl A.; Jung, Il-Won

    2012-01-01

    As part of a larger investigation into potential effects of climate change on estuarine habitats in the Pacific Northwest, we estimated changes in freshwater inputs into four estuaries: Coquille River estuary, South Slough of Coos Bay, and Yaquina Bay in Oregon, and Willapa Bay in Washington. We used the U.S. Geological Survey's Precipitation Runoff Modeling System (PRMS) to model watershed hydrological processes under current and future climatic conditions. This model allowed us to explore possible shifts in coastal hydrologic regimes at a range of spatial scales. All modeled watersheds are located in rainfall-dominated coastal areas with relatively insignificant base flow inputs, and their areas vary from 74.3 to 2,747.6 square kilometers. The watersheds also vary in mean elevation, ranging from 147 meters in the Willapa to 1,179 meters in the Coquille. The latitudes of watershed centroids range from 43.037 degrees north latitude in the Coquille River estuary to 46.629 degrees north latitude in Willapa Bay. We calibrated model parameters using historical climate grid data downscaled to one-sixteenth of a degree by the Climate Impacts Group, and historical runoff from sub-watersheds or neighboring watersheds. Nash Sutcliffe efficiency values for daily flows in calibration sub-watersheds ranged from 0.71 to 0.89. After calibration, we forced the PRMS models with four North American Regional Climate Change Assessment Program climate models: Canadian Regional Climate Model-(National Center for Atmospheric Research) Community Climate System Model version 3, Canadian Regional Climate Model-Canadian Global Climate Model version 3, Hadley Regional Model version 3-Hadley Centre Climate Model version 3, and Regional Climate Model-Canadian Global Climate Model version 3. These are global climate models (GCMs) downscaled with regional climate models that are embedded within the GCMs, and all use the A2 carbon emission scenario developed by the Intergovernmental Panel on Climate Change. With these climate-forcing outputs, we derived the mean change in flow from the period encompassing the 1980s (1971-1995) to the period encompassing the 2050s (2041-2065). Specifically, we calculated percent change in mean monthly flow rate, coefficient of variation, top 5 percent of flow, and 7-day low flow. The trends with the most agreement among climate models and among watersheds were increases in autumn mean monthly flows, especially in October and November, decreases in summer monthly mean flow, and increases in the top 5 percent of flow. We also estimated variance in PRMS outputs owing to parameter uncertainty and the selection of climate model using Latin hypercube sampling. This analysis showed that PRMS low-flow simulations are more uncertain than medium or high flow simulations, and that variation among climate models was a larger source of uncertainty than the hydrological model parameters. These results improve our understanding of how climate change may affect the saltwater-freshwater balance in Pacific Northwest estuaries, with implications for their sensitive ecosystems.

  3. Accuracy of Phase-Contrast Velocity Mapping Proximal and Distal to Stent Artifact During Cardiac Magnetic Resonance Imaging.

    PubMed

    Avitabile, Catherine M; Harris, Matthew A; Doddasomayajula, Ravi S; Chopski, Steven G; Gillespie, Matthew J; Dori, Yoav; Glatz, Andrew C; Fogel, Mark A; Whitehead, Kevin K

    2018-06-15

    Little data are available on the accuracy of phase-contrast magnetic resonance imaging (PC-MRI) velocity mapping in the vicinity of intravascular metal stents other than nitinol stents. Therefore, we sought to determine this accuracy using in vitro experiments. An in vitro flow phantom was used with 3 stent types: (1) 316L stainless steel, (2) nitinol self-expanding, and (3) platinum-iridium. Steady and pulsatile flow was delivered with a magnetic resonance imaging-compatible pump (CardioFlow 5000, Shelley Medical, London, Ontario, Canada). Flows were measured using a transit time flow meter (ME13PXN, Transonic, Inc, Ithaca, New York). Mean flows ranged from 0.5 to 7 L/min. For each condition, 5 PC-MRI acquisitions were made: within the stent, immediately adjacent to both edges of the stent artifact, and 1 cm upstream and downstream of the artifact. Mean PC-MRI flows were calculated by segmenting the tube lumen using clinical software (ARGUS, Siemens, Inc, Erlangen, Germany). PC-MRI and flow meter flows were compared by location and stent type using linear regression, Bland-Altman, and intraclass correlation (ICC). PC-MRI flows within the stent artifact were inaccurate for all stents studied, generally underestimating flow meter-measured flow. Agreement between PC-MRI and flow meter-measured flows was excellent for all stent types, both immediately adjacent to and 1 cm away from the edge of the stent artifact. Agreement was highest for the platinum-iridium stent (R = 0.999, ICC = 0.999) and lowest for the nitinol stent (R = 0.993, ICC = 0.987). In conclusion, PC-MRI flows are highly accurate just upstream and downstream of a variety of clinically used stents, supporting its use to directly measure flows in stented vessels. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wyatt, Douglas

    Planning for ultimate Decontamination and Decommissioning (D and D) of a nuclear facility is as much a part of a successful nuclear strategy as is the ultimate disposal of radioactive waste. As facilities, in this case radioactive waste disposal trenches, are closed and abandoned leading to ultimate decommissioning, long term monitoring may be required. However, preplanning by characterizing, modeling, and monitoring the environment around the facility prior to and during operations will allow a performance assessment to be made and future behavior predicted. In the radioactive waste burial grounds of the Savannah River Site new slit trenches were constructed tomore » receive demolition debris associated with site foot print reduction. Some of the construction debris and associated process waste contained small amounts of tritium. Since the trenches were constructed over an existing tritium groundwater plume the monitoring and performance assessment of the trench, particularly with respect to tritium contributions to the vadose zone and groundwater, were important. These disposal trenches vary in length and width but are typically constructed within the upper 7 to 8 meters (21 to 24 feet) of the local sediments. The unconfined aquifer (water table) typically underlies the area at depths varying from 20 to 24 meters (60 to 72 feet), depending on elevation. Therefore, with downward flow and 13 to 16 meters (40 to 48 feet) of unsaturated sediments separating the base of the waste trenches from the unconfined aquifer, there was potential for an environmental impact to the sediments within the vadose zone and to the underlying groundwater. Monitoring and predicting this impact can support ultimate D and D activities and future performance assessment evaluation. From this work several key observations were made that will support long term monitoring and subsequent D and D: - The observed lateral variation of thinly bedded sands and clays may be less than 20 meters particularly if lenticular sands are present. Ultimate D and D should consider monitoring and remedial activities that consider sampling on scales to address this issue. - The detailed modeling, when compared with the modeled depositional patterns, indicates flow paths for vadose zone fluids, therefore a plan should allow for these flow paths. - Detailed lithostratigraphic modeling, when based on correlations between soil properties, CPT soundings and borehole geophysical logs, can aid in precision placement of subsurface sensors and sample points for performance monitoring and D and D assessment.« less

  5. Modifications to the 4x7 meter tunnel for acoustic research: Engineering feasibility study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The NASA-Langley Research Center 4 x 7 Meter Low Speed Wind Tunnel is currently being used for low speed aerodynamics, V/STOL aerodynamics and, to a limited extent, rotorcraft noise research. The deficiencies of this wind tunnel for both aerodynamics and aeroacoustics research have been recognized for some time. Modifications to the wind tunnel are being made to improve the test section flow quality and to update the model cart systems. A further modification of the 4 x 7 Meter Wind Tunnel to permit rotorcraft model acoustics research has been proposed. As a precursor to the design of the proposed modifications, NASA is conducted both in-house and contracted studies to define the acoustic environment within the wind tunnel and to provide recommendations or the reduction of the wind tunnel background noise to a level acceptable to acoustics researchers. One of these studies by an acoustics consultant, has produced the primary reference documents that define the wind tunnel noise sources and outline recommended solutions.

  6. Characterization of cavity flow fields using pressure data obtained in the Langley 0.3-Meter Transonic Cryogenic Tunnel

    NASA Technical Reports Server (NTRS)

    Tracy, M. B.; Plentovich, E. B.

    1993-01-01

    Static and fluctuating pressure distributions were obtained along the floor of a rectangular-box cavity in an experiment performed in the LaRC 0.3-Meter Transonic Cryogenic Tunnel. The cavity studied was 11.25 in. long and 2.50 in. wide with a variable height to obtain length-to-height ratios of 4.4, 6.7, 12.67, and 20.0. The data presented herein were obtained for yaw angles of 0 deg and 15 deg over a Mach number range from 0.2 to 0.9 at a Reynolds number of 30 x 10(exp 6) per ft with a boundary-layer thickness of approximately 0.5 in. The results indicated that open and transitional-open cavity flow supports tone generation at subsonic and transonic speeds at Mach numbers of 0.6 and above. Further, pressure fluctuations associated with acoustic tone generation can be sustained when static pressure distributions indicate that transitional-closed and closed flow fields exist in the cavity. Cavities that support tone generation at 0 deg yaw also supported tone generation at 15 deg yaw when the flow became transitional-closed. For the latter cases, a reduction in tone amplitude was observed. Both static and fluctuating pressure data must be considered when defining cavity flow fields, and the flow models need to be refined to accommodate steady and unsteady flows.

  7. A vadose zone water fluxmeter with divergence control

    NASA Astrophysics Data System (ADS)

    Gee, G. W.; Ward, A. L.; Caldwell, T. G.; Ritter, J. C.

    2002-08-01

    Unsaturated water flux densities are needed to quantify water and contaminant transfer within the vadose zone. However, water flux densities are seldom measured directly and often are predicted with uncertainties of an order or magnitude or more. A water fluxmeter was designed, constructed, and tested to directly measure drainage fluxes in field soils. The fluxmeter was designed to minimize divergence. It concentrates flow into a narrow sensing region filled with a fiberglass wick. The wick applies suction, proportional to its length, and passively drains the meter. The meter can be installed in an augured borehole at almost any depth below the root zone. Water flux through the meter is measured with a self-calibrating tipping bucket, with a sensitivity of ~4 mL tip-1. For our meter this is equivalent to detection limit of ~0.1 mm. Passive-wick devices previously have not properly corrected for flow divergence. Laboratory measurements supported predictions of a two-dimensional (2-D) numerical model, which showed that control of the collector height H and knowledge of soil hydraulic properties are required for improving divergence control, particularly at fluxes below 1000 mm yr-1. The water fluxmeter is simple in concept, is inexpensive, and has the capability of providing continuous and reliable monitoring of unsaturated water fluxes ranging from less than 1 mm yr-1 to more than 1000 mm yr-1.

  8. A vadose zone water fluxmeter with divergence control

    USGS Publications Warehouse

    Gee, G.W.; Ward, A.L.; Caldwell, T.G.; Ritter, J.C.

    2002-01-01

    Unsaturated water flux densities are needed to quantify water and contaminant transfer within the vadose zone. However, water flux densities are seldom measured directly and often are predicted with uncertainties of an order or magnitude or more. A water fluxmeter was designed, constructed, and tested to directly measure drainage fluxes in field soils. The fluxmeter was designed to minimize divergence. It concentrates flow into a narrow sensing region filled with a fiberglass wick. The wick applies suction, proportional to its length, and passively drains the meter. The meter can be installed in an augured borehole at almost any depth below the root zone. Water flux through the meter is measured with a self‐calibrating tipping bucket, with a sensitivity of ∼4 mL tip−1. For our meter this is equivalent to detection limit of ∼0.1 mm. Passive‐wick devices previously have not properly corrected for flow divergence. Laboratory measurements supported predictions of a two‐dimensional (2‐D) numerical model, which showed that control of the collector height H and knowledge of soil hydraulic properties are required for improving divergence control, particularly at fluxes below 1000 mm yr−1. The water fluxmeter is simple in concept, is inexpensive, and has the capability of providing continuous and reliable monitoring of unsaturated water fluxes ranging from less than 1 mm yr−1 to more than 1000 mm yr−1.

  9. Comparison of five portable peak flow meters

    PubMed Central

    Takara, Glaucia Nency; Ruas, Gualberto; Pessoa, Bruna Varanda; Jamami, Luciana Kawakami; Di Lorenzo, Valéria Amorim Pires; Jamami, Mauricio

    2010-01-01

    OBJECTIVE To compare the measurements of spirometric peak expiratory flow (PEF) from five different PEF meters and to determine if their values are in agreement. Inaccurate equipment may result in incorrect diagnoses of asthma and inappropriate treatments. METHODS Sixty-eight healthy, sedentary and insufficiently active subjects, aged from 19 to 40 years, performed PEF measurements using Air Zone®, Assess®, Galemed®, Personal Best® and Vitalograph® peak flow meters. The highest value recorded for each subject for each device was compared to the corresponding spirometric values using Friedman’s test with Dunn’s post-hoc (p<0.05), Spearman’s correlation test and Bland-Altman’s agreement test. RESULTS The median and interquartile ranges for the spirometric values and the Air Zone®, Assess®, Galemed®, Personal Best® and Vitalograph® meters were 428 (263–688 L/min), 450 (350–800 L/min), 420 (310–720 L/min), 380 (300–735 L/min), 400 (310–685 L/min) and 415 (335–610 L/min), respectively. Significant differences were found when the spirometric values were compared to those recorded by the Air Zone® (p<0.001) and Galemed ® (p<0.01) meters. There was no agreement between the spirometric values and the five PEF meters. CONCLUSIONS The results suggest that the values recorded from Galemed® meters may underestimate the actual value, which could lead to unnecessary interventions, and that Air Zone® meters overestimate spirometric values, which could obfuscate the need for intervention. These findings must be taken into account when interpreting both devices’ results in younger people. These differences should also be considered when directly comparing values from different types of PEF meters. PMID:20535364

  10. A three-dimensional turbulent separated flow and related mesurements

    NASA Technical Reports Server (NTRS)

    Pierce, F. J.

    1985-01-01

    The applicability of and the limits on the applicability of 11 near wall similarity laws characterizing three-dimensional turbulent boundary layer flows were determined. A direct force sensing local wall shear stress meter was used in both pressure-driven and shear-driven three-dimensional turbulent boundary layers, together with extensive mean velocity field and wall pressure field data. This resulted in a relatively large number of graphical comparisons of the predictive ability of 10 of these 11 similarity models relative to measured data over a wide range of flow conditions. Documentation of a complex, separated three-dimensional turbulent flow as a standard test case for evaluating the predictive ability of numerical codes solving such flows is presented.

  11. Two-phase flow measurements with advanced instrumented spool pieces and local conductivity probes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turnage, K.G.; Davis, C.E.

    1979-01-01

    A series of two-phase, air-water and steam-water tests performed with instrumented spool pieces and with conductivity probes obtained from Atomic Energy of Canada, Ltd. is described. The behavior of the three-beam densitometer, turbine meter, and drag flowmeter is discussed in terms of two-phase models. Application of some two-phase mass flow models to the recorded spool piece data is made and preliminary results are shown. Velocity and void fraction information derived from the conductivity probes is presented and compared to velocities and void fractions obtained using the spool piece instrumentation.

  12. Application of Geographical Information System Arc/info Grid-Based Surface Hyrologic Modeling to the Eastern Hellas Region, Mars

    NASA Astrophysics Data System (ADS)

    Mest, S. C.; Harbert, W.; Crown, D. A.

    2001-05-01

    Geographical Information System GRID-based raster modeling of surface water runoff in the eastern Hellas region of Mars has been completed. We utilized the 0.0625 by 0.0625 degree topographic map of Mars collected by the Mars Global Surveyor Mars Orbiter Laser Altimeter (MOLA) instrument to model watershed and surface runoff drainage systems. Scientific interpretation of these models with respect to ongoing geological mapping is presented in Mest et al., (2001). After importing a region of approximately 77,000,000 square kilometers into Arc/Info 8.0.2 we reprojected this digital elevation model (DEM) from a Mars sphere into a Mars ellipsoid. Using a simple cylindrical geographic projection and horizontal spatial units of decimal degrees and then an Albers projection with horizontal spatial units of meters, we completed basic hydrological modeling. Analysis of the raw DEM to determine slope, aspect, flow direction, watershed and flow accumulation grids demonstrated the need for correction of single pixel sink anomalies. After analysis of zonal elevation statistics associated with single pixel sinks, which identified 0.8 percent of the DEM points as having undefined surface water flow directions, we filled single pixel sink values of 89 meters or less. This correction is comparable with terrestrial DEMs that contain 0.9 percent to 4.7 percent of cells, which are sinks (Tarboton et al., 1991). The fill-corrected DEM was then used to determine slope, aspect, surface water flow direction and surface water flow accumulation. Within the region of interest 8,776 watersheds were identified. Using Arc/Info GRID flow direction and flow accumulation tools, regions of potential surface water flow accumulation were identified. These networks were then converted to a Strahler ordered stream network. Surface modeling produced Strahler orders one through six. As presented in Mest et al., (2001) comparisons of mapped features may prove compatible with drainage networks and watersheds derived using this methodology. Mest, Scott C., Crown, David A., and Harbert, William, 2001, Highland drainage basins and valley networks in the eastern Hellas Region of Mars, Abstract 1419, Lunar and Planetary Science XXXII Meeting Houston (CDROM). Tarboton D. G., Bras, R. L., and Rodriguez-Iturbe, 1991, On the Extraction of Channel Networks from Digital Elevation Data, Hydrological Processes, v. 5, 81-100. http://viking.eps.pitt.edu

  13. Multiple flow processes accompanying a dam-break flood in a small upland watershed, Centralia, Washington

    USGS Publications Warehouse

    Costa, John E.

    1994-01-01

    On October 5, 1991, following 35 consecutive days of dry weather, a 105-meter long, 37-meter wide, 5.2-meter deep concrete-lined watersupply reservoir on a hillside in the eastern edge of Centralia, Washington, suddenly failed, sending 13,250 cubic meters of water rushing down a small, steep tributary channel into the city. Two houses were destroyed, several others damaged, mud and debris were deposited in streets, on lawns, and in basements over four city blocks, and 400 people were evacuated. The cause of failure is believed to have been a sliding failure along a weak seam or joint in the siltstone bedrock beneath the reservoir, possibly triggered by increased seepage into the rock foundation through continued deterioration of concrete panel seams, and a slight rise (0.6 meters) in the pool elevation. A second adjacent reservoir containing 18,900 cubic meters of water also drained, but far more slowly, when a 41-cm diameter connecting pipe was broken by the landslide. The maximum discharge resulting from the dam-failure was about 71 cubic meters per second. A reconstructed hydrograph based on the known reservoir volume and calculated peak discharge indicates the flood duration was about 6.2 minutes. Sedimentologic evidence, high-water mark distribution, and landforms preserved in the valley floor indicate that the dam failure flood consisted of two flow phases: an initial debris flow that deposited coarse bouldery sediment along the slope-area reach as it lost volume, followed soon after by a water-flood that achieved a stage about one-half meter higher than the debris flow. The Centralia dam failure is one of three constructed dams destroyed by rapid foundation failure that defines the upper limits of an envelope curve of peak flood discharge as a function of potential energy for failed constructed dams worldwide.

  14. 75 FR 47207 - Airworthiness Directives; Airbus Model A330-200 and -300 Series Airplanes, and Model A340-200...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... airplanes. The AD requires replacing or modifying the Halon dual-filter assemblies of the flow metering fire...-filter assembly P/N QA06753 is embodied in production through Airbus modification 40041. The Halon dual- filter assembly P/N QA06753-01 is only embodied in service through Airbus Service Bulletin A330-26-3030...

  15. Heat flow in the flanks of the Oceanographer-Hayes segment of the Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Le Gal, V.; Lucazeau, F.; Cannat, M.; Battani, A.; Poort, J.; Guichet, X.; Monnin, C.; Fontaine, F. J.; Leroy, S. D.

    2016-12-01

    It is currently estimated that a third of the oceanic heat loss is due to fluid circulation in the oceanic crust. Besides high and low temperature fluid discharge at ridge axis, off-axis low temperature fluid circulations can affect large volumes of the oceanic crust. Long term investigations of the Eastern Juan de Fuca ridge flank (Hutnak et al.2006) have established a circulation pattern where hydrothermal discharge and recharge occur at basement outcrops and where sediment is mostly impermeable. Here, we present results from the recent Oceanograflu cruise (2013), on the Oceanographer-Hayes segment ridge flanks of the Mid-Atlantic ridge in crust 5 and 12 myrs in age. On both flanks, we obtained 185 temperature gradients and conductivities in-situ, 30 Küllenberg cores (3 to 5 meters long) coupled with temperature gradients in-situ and conductivity measurements onboard. These data are interpreted in terms of heat flow values and are generally lower than the conductive cooling model. Several temperature-depth profiles don't show linear gradients, but rather sigmoid shapes or inverse gradients suggesting superficial circulations through the first meters of sediments. The corresponding heat flow pattern is not similar to the one observed at Juan de Fuca. No systematic links have been observed between basement outcrops and lower or higher heat flow which would point to discharge or recharge sites. Instead, the pattern recalls studies in the North Pond area (Langseth et al.1992), with a clear predominance of low heat flow values over the site. We propose that the North Pond circulation model is applicable to large portions of slow-spreading ridge flanks such as the Atlantic. In this model, seawater cools the uppermost crust below sediments in basins that are typically tens of kms wide, reducing the surface heat flow under cooling model values. Based on subsidence rates, these shallow hydrothermal circulations have a minor impact on the cooling of the diverging plates.

  16. A method of calibrating wind velocity sensors with a modified gas flow calibrator

    NASA Technical Reports Server (NTRS)

    Stump, H. P.

    1978-01-01

    A procedure was described for calibrating air velocity sensors in the exhaust flow of a gas flow calibrator. The average velocity in the test section located at the calibrator exhaust was verified from the mass flow rate accurately measured by the calibrator's precision sonic nozzles. Air at elevated pressures flowed through a series of screens, diameter changes, and flow straighteners, resulting in a smooth flow through the open test section. The modified system generated air velocities of 2 to 90 meters per second with an uncertainty of about two percent for speeds below 15 meters per second and four percent for the higher speeds. Wind tunnel data correlated well with that taken in the flow calibrator.

  17. Blueschist preservation in a retrograded, high-pressure, low-temperature metamorphic terrane, Tinos, Greece: Implications for fluid flow paths in subduction zones

    NASA Astrophysics Data System (ADS)

    Breeding, Christopher M.; Ague, Jay J.; BröCker, Michael; Bolton, Edward W.

    2003-01-01

    The preservation of high-pressure, low-temperature (HP-LT) mineral assemblages adjacent to marble unit contacts on the Cycladic island of Tinos in Greece was investigated using a new type of digital outcrop mapping and numerical modeling of metamorphic fluid infiltration. Mineral assemblage distributions in a large blueschist outcrop, adjacent to the basal contact of a 150-meter thick marble horizon, were mapped at centimeter-scale resolution onto digital photographs using a belt-worn computer and graphics editing software. Digital mapping reveals that while most HP-LT rocks in the outcrop were pervasively retrograded to greenschist facies, the marble-blueschist contact zone underwent an even more intense retrogression. Preservation of HP-LT mineral assemblages was mainly restricted to a 10-15 meter zone (or enclave) adjacent to the intensely retrograded lithologic contact. The degree and distribution of the retrograde overprint suggests that pervasively infiltrating fluids were channelized into the marble-blueschist contact and associated veins and flowed around the preserved HP-LT enclave. Numerical modeling of Darcian flow, based on the field observations, suggests that near the marble horizon, deflections in fluid flow paths caused by flow channelization along the high-permeability marble-blueschist contact zone likely resulted in very large fluid fluxes along the lithologic contact and significantly smaller fluxes (as much as 8 times smaller than the input flux) within the narrow, low-flux regions where HP-LT minerals were preserved adjacent to the contact. Our results indicate that lithologic contacts are important conduits for metamorphic fluid flow in subduction zones. Channelization of retrograde fluids into these discrete flow conduits played a critical role in the preservation of HP-LT assemblages.

  18. Analytical Modeling of Groundwater Seepages to St. Lucie Estuary

    NASA Astrophysics Data System (ADS)

    Lee, J.; Yeh, G.; Hu, G.

    2008-12-01

    In this paper, six analytical models describing hydraulic interaction of stream-aquifer systems were applied to St Lucie Estuary (SLE) River Estuaries. These are analytical solutions for: (1) flow from a finite aquifer to a canal, (2) flow from an infinite aquifer to a canal, (3) the linearized Laplace system in a seepage surface, (4) wave propagation in the aquifer, (5) potential flow through stratified unconfined aquifers, and (6) flow through stratified confined aquifers. Input data for analytical solutions were obtained from monitoring wells and river stages at seepage-meter sites. Four transects in the study area are available: Club Med, Harbour Ridge, Lutz/MacMillan, and Pendarvis Cove located in the St. Lucie River. The analytical models were first calibrated with seepage meter measurements and then used to estimate of groundwater discharges into St. Lucie River. From this process, analytical relationships between the seepage rate and river stages and/or groundwater tables were established to predict the seasonal and monthly variation in groundwater seepage into SLE. It was found the seepage rate estimations by analytical models agreed well with measured data for some cases but only fair for some other cases. This is not unexpected because analytical solutions have some inherently simplified assumptions, which may be more valid for some cases than the others. From analytical calculations, it is possible to predict approximate seepage rates in the study domain when the assumptions underlying these analytical models are valid. The finite and infinite aquifer models and the linearized Laplace method are good for sites Pendarvis Cove and Lutz/MacMillian, but fair for the other two sites. The wave propagation model gave very good agreement in phase but only fairly agreement in magnitude for all four sites. The stratified unconfined and confined aquifer models gave similarly good agreements with measurements at three sites but poorly at the Club Med site. None of the analytical models presented here can fit the data at this site. To give better estimates at all sites numerical modeling that couple river hydraulics and groundwater flow involving less simplifications of and assumptions for the system may have to be adapted.

  19. 49 CFR 192.381 - Service lines: Excess flow valve performance standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... hour (0.57 cubic meters per hour); or (B) For an excess flow valve designed to prevent equalization of pressure across the valve, to no more than 0.4 cubic feet per hour (.01 cubic meters per hour); and (4) Not... the manufacturer according to an industry specification, or the manufacturer's written specification...

  20. 49 CFR 192.381 - Service lines: Excess flow valve performance standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... hour (0.57 cubic meters per hour); or (B) For an excess flow valve designed to prevent equalization of pressure across the valve, to no more than 0.4 cubic feet per hour (.01 cubic meters per hour); and (4) Not... the manufacturer according to an industry specification, or the manufacturer's written specification...

  1. 49 CFR 192.381 - Service lines: Excess flow valve performance standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... hour (0.57 cubic meters per hour); or (B) For an excess flow valve designed to prevent equalization of pressure across the valve, to no more than 0.4 cubic feet per hour (.01 cubic meters per hour); and (4) Not... the manufacturer according to an industry specification, or the manufacturer's written specification...

  2. 77 FR 63537 - Greenhouse Gas Reporting Program: Proposed Amendments and Confidentiality Determinations for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-16

    ... consumption. (See Section for ``all flow meters, weigh III.B.6). scales, pressure gauges and thermometers... apportioning consumption. (See Section III.B.8). factors by using direct measurements using gas flow meters or... consumption. Revising 40 CFR 98.94(c)(2)(i) to allow reporters to select a period of the reporting year and...

  3. 49 CFR 192.381 - Service lines: Excess flow valve performance standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... hour (0.57 cubic meters per hour); or (B) For an excess flow valve designed to prevent equalization of pressure across the valve, to no more than 0.4 cubic feet per hour (.01 cubic meters per hour); and (4) Not... the manufacturer according to an industry specification, or the manufacturer's written specification...

  4. 40 CFR 98.423 - Calculating CO2 supply.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... as allowed in paragraph (b) of this section, calculate the annual mass of CO2 captured, extracted... mass of CO2 for all flow meters according to the procedures specified in paragraph (a)(3) of this section. (1) For each mass flow meter, you shall calculate quarterly the mass of CO2 in a CO2 stream in...

  5. 40 CFR 98.423 - Calculating CO2 supply.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... as allowed in paragraph (b) of this section, calculate the annual mass of CO2 captured, extracted... mass of CO2 for all flow meters according to the procedures specified in paragraph (a)(3) of this section. (1) For each mass flow meter, you shall calculate quarterly the mass of CO2 in a CO2 stream in...

  6. 40 CFR 98.423 - Calculating CO2 supply.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... as allowed in paragraph (b) of this section, calculate the annual mass of CO2 captured, extracted... mass of CO2 for all flow meters according to the procedures specified in paragraph (a)(3) of this section. (1) For each mass flow meter, you shall calculate quarterly the mass of CO2 in a CO2 stream in...

  7. Calibration of the BASS acoustic current meter with carrageenan agar

    USGS Publications Warehouse

    Morrison, A.T.; Williams, A.J.; Martini, M.

    1993-01-01

    The BASS current meter can measure currents down to the millimeter per second range. Due to the dependence of zero offset on pressure, determining a sensor referenced velocity requires accurate in situ zeroing of the meter. Previously, flow was restricted during calibration by placing plastic bags around the acoustic volume. In this paper, bacterial grade and carrageenan agars are used in the laboratory to create a zero flow condition during calibration and are shown to be acoustically transparent. Additionally, the results of open ocean and dockside carrageenan and plastic bag comparisons are presented. Carrageenan is shown to reliably provide a low noise, zero mean flow environment that is largely independent of ambient conditions. The improved zeros make millimeter per second accuracy possible under field conditions.

  8. Prediction based active ramp metering control strategy with mobility and safety assessment

    NASA Astrophysics Data System (ADS)

    Fang, Jie; Tu, Lili

    2018-04-01

    Ramp metering is one of the most direct and efficient motorway traffic flow management measures so as to improve traffic conditions. However, owing to short of traffic conditions prediction, in earlier studies, the impact on traffic flow dynamics of the applied RM control was not quantitatively evaluated. In this study, a RM control algorithm adopting Model Predictive Control (MPC) framework to predict and assess future traffic conditions, which taking both the current traffic conditions and the RM-controlled future traffic states into consideration, was presented. The designed RM control algorithm targets at optimizing the network mobility and safety performance. The designed algorithm is evaluated in a field-data-based simulation. Through comparing the presented algorithm controlled scenario with the uncontrolled scenario, it was proved that the proposed RM control algorithm can effectively relieve the congestion of traffic network with no significant compromises in safety aspect.

  9. In Situ Soil Venting - Full Scale Test, Hill AFB, Guidance Document. Volume 2

    DTIC Science & Technology

    1991-08-01

    oxidizer. Another system was connected to the existing air scrubber of a building (Reference 23). The self-contained unit reported by Rippberger...devices on the market for flow rate measurement. Some of the more common devices are orifice meters, venturi meters, rotameters, pitot tubes, hot-wire...Notes on how to size and construct orifice meters can be found in Reference 41. * Venturi Meter - A venturi meter works basically on the same

  10. In situ determination of heat flow in unconsolidated sediments

    USGS Publications Warehouse

    Sass, J.H.; Kennelly, J.P.; Wendt, W.E.; Moses, T.H.; Ziagos, J.P.

    1979-01-01

    Subsurface thermal measurements are the most effective, least ambiguous tools for identifying and delineating possible geothernml resources. Measurements of thermal gradient in the upper few tens of meters generally are sufficient to outline the major anomalies, but it is always desirable to combine these gradients with reliable estimates of thermal conductivity to provide data on the energy flux and to constrain models for the heat sources responsible for the observed, near-surface thermal anomalies. The major problems associated with heat-flow measurements in the geothermal exploration mode are concerned with the economics of casing and/or grouting holes, the repeated site visits necessary to obtain equilibrium temperature values, the possible legal liability associated with the disturbance of underground aquifers, the surface hazards presented by pipes protruding from the ground, and the security problems associated with leaving cased holes open for periods of weeks to months. We have developed a technique which provides reliable 'real-time' determinations of temperature, thermal conductivity, and hence, of heat flow during the drilling operation in unconsolidated sediments. A combined temperature, gradient, and thermal conductivity experiment can be carried out, by driving a thin probe through the bit about 1.5 meters into the formation in the time that would otherwise be required for a coring trip. Two or three such experiments over the depth range of, say, 50 to 150 meters provide a high-quality heat-flow determination at costs comparable to those associated with a standard cased 'gradient hole' to comparable depths. The hole can be backfilled and abandoned upon cessation of drilling, thereby eliminating the need for casing, grouting, or repeated site visits.

  11. Flow Meter Based on Freely Suspended Smectic Liquid Crystal Films

    NASA Astrophysics Data System (ADS)

    Green, Adam; Qi, Zhiyuan; Park, Cheol; Glaser, Matthew; Maclennan, Joseph; Clark, Noel

    We present the realization of a idealized 2D hydrodynamic system coupled to air-flow, and show that freely suspended films (FSF) of smectic liquid crystals can be used as a novel flow-meter. Freely-suspended films of liquid crystals are one of the closest physical realizations of an idealized 2D fluid. The velocity of air-flow above a film suspended above a channel can be inferred by studying the velocity profile of the smectic film. This velocity profile can be measured using digital video microscopy to track the inclusions present in the moving film. The velocity profile is then fitted to the coupled 2D solutions of an embedded fluid in air, and the velocity of the air can then be extracted. This flow meter serves as a demonstration of a robust test-bed for further exploration of 2D hydrodynamics. This work was supported by NASA Grant No. NNX-13AQ81G, NSF MRSEC Grant No. DMR-0820579, and DMR-1420736.

  12. Development and evaluation of an ultrasonic ground water seepage meter.

    PubMed

    Paulsen, R J; Smith, C F; O'Rourke, D; Wong, T F

    2001-01-01

    Submarine ground water discharge can influence significantly the near-shore transport and flux of chemicals into the oceans. Quantification of the sources and rates of such discharge requires a ground water seepage meter that provides continuous measurements at high resolution over an extended period of time. An ultrasonic flowmeter has been adapted for such measurements in the submarine environment. Connected to a steel collection funnel, the meter houses two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube. By monitoring the perturbations of fluid flow on the propagation of sound waves inside the flow tube, the ultrasonic meter can measure both forward and reverse fluid flows in real time. Laboratory and field calibrations show that the ultrasonic meter can resolve ground water discharges on the order of 0.1 microm/sec, and it is sufficiently robust for deployment in the field for several days. Data from West Neck Bay, Shelter Island, New York, elucidate the temporal and spatial heterogeneity of submarine ground water discharge and its interplay with tidal loading. A negative correlation between the discharge and tidal elevation was generally observed. A methodology was also developed whereby data for the sound velocity as a function of temperature can be used to infer the salinity and source of the submarine discharge. Independent measurements of electrical conductance were performed to validate this methodology.

  13. Inert gas thrusters

    NASA Technical Reports Server (NTRS)

    Kaufman, H. R.; Robinson, R. S.

    1979-01-01

    Inert gas thrusters considered for space propulsion systems were investigated. Electron diffusion across a magnetic field was examined utilizing a basic model. The production of doubly charged ions was correlated using only overall performance parameters. The use of this correlation is therefore possible in the design stage of large gas thrusters, where detailed plasma properties are not available. Argon hollow cathode performance was investigated over a range of emission currents, with the positions of the inert, keeper, and anode varied. A general trend observed was that the maximum ratio of emission to flow rate increased at higher propellant flow rates. It was also found that an enclosed keeper enhances maximum cathode emission at high flow rates. The maximum cathode emission at a given flow rate was associated with a noisy high voltage mode. Although this mode has some similarities to the plume mode found at low flows and emissions, it is encountered by being initially in the spot mode and increasing emission. A detailed analysis of large, inert-gas thruster performance was carried out. For maximum thruster efficiency, the optimum beam diameter increases from less than a meter at under 2000 sec specific impulse to several meters at 10,000 sec. The corresponding range in input power ranges from several kilowatts to megawatts.

  14. NaK Plugging Meter Design for the Feasibility Test Loops

    NASA Technical Reports Server (NTRS)

    Pearson, J. Boise; Godfroy, Thomas J.; Reid, Robert S.; Polzin, Kurt A.

    2008-01-01

    The design and predicted performance of a plugging meter for use in the measurement of NaK impurity levels are presented. The plugging meter is incorporated into a Feasibility Test Loop (FTL), which is a small pumped-NaK loop designed to enable the rapid, small-scale evaluation of techniques such as in situ purification methods and to permit the measurement of bulk material transport effects (not mechanisms) under flow conditions that are representative of a fission surface power reactor. The FTL operates at temperatures similar to those found in a reactor, with a maximum hot side temperature of 900 K and a corresponding cold side temperature of 860 K. In the plugging meter a low flow rate bypass loop is cooled until various impurities (primarily oxides) precipitate out of solution. The temperatures at which these impurities precipitate are indicative of the level of impurities in the NaK. The precipitates incrementally plug a small orifice in the bypass loop, which is detected by monitoring changes in the liquid metal flow rate.

  15. Application of acoustic doppler velocimeters for streamflow measurements

    USGS Publications Warehouse

    Rehmel, M.

    2007-01-01

    The U.S. Geological Survey (USGS) principally has used Price AA and Price pygmy mechanical current meters for measurement of discharge. New technologies have resulted in the introduction of alternatives to the Price meters. One alternative, the FlowTracker acoustic Doppler velocimeter, was designed by SonTek/YSI to make streamflow measurements in wadeable conditions. The device measures a point velocity and can be used with standard midsection method algorithms to compute streamflow. The USGS collected 55 quality-assurance measurements with the FlowTracker at 43 different USGS streamflow-gaging stations across the United States, with mean depths from 0.05to0.67m, mean velocities from 13 to 60 cm/s, and discharges from 0.02 to 12.4m3/s. These measurements were compared with Price mechanical current meter measurements. Analysis of the comparisons shows that the FlowTracker discharges were not statistically different from the Price meter discharges at a 95% confidence level. ?? 2007 ASCE.

  16. An electrode polarization impedance based flow sensor for low water flow measurement

    NASA Astrophysics Data System (ADS)

    Yan, Tinghu; Sabic, Darko

    2013-06-01

    This note describes an electrode polarization impedance based flow sensor for low water flow measurement. It consists of two pairs of stainless steel electrodes set apart and inserted into a non-conductive flow tube with each pair of electrodes placed diametrically at the opposite sides. The flow sensor is modeled as a typical four-electrode system of which two electrodes are current-carrying and the other two serve as output pick ups. The polarization impedances of the two current carrying electrodes are affected by water flows resulting in changes of differential potential between the two pick-up electrodes which are separated by the same fluid. The interrogation of the two excitation electrodes with dc biased ac signals offers significantly higher sensor sensitivities to flow. The prototype flow sensor constructed for a 20 mm diameter pipeline was able to measure water flow rate as low as tested at 1.06 l h-1 and remained sensitive at a flow rate of 25.18 l h-1 when it was driven with a sinusoidal voltage at 1000 Hz with a peak ac amplitude of 2 V and a dc offset of +8 V. The nonlinear characteristics of the sensor response indicate that the sensor is more sensitive at low flows and will not be able to measure at very high flows. Additional experiments are needed to evaluate the influences of impurities, chemical species, ions constituents, conductivity and temperature over a practical range of residential water conditions, the effects of fluctuating ground signals, measurement uncertainty, power consumption, compensation of effects and practical operations. The flow sensor (principle) presented may be used as (in) a secondary sensor in combination with an existing electronic water meter to extend the low end of measurement range in residential water metering.

  17. A conflict analysis of 4D descent strategies in a metered, multiple-arrival route environment

    NASA Technical Reports Server (NTRS)

    Izumi, K. H.; Harris, C. S.

    1990-01-01

    A conflict analysis was performed on multiple arrival traffic at a typical metered airport. The Flow Management Evaluation Model (FMEM) was used to simulate arrival operations using Denver Stapleton's arrival route structure. Sensitivities of conflict performance to three different 4-D descent strategies (clear-idle Mach/Constant AirSpeed (CAS), constant descent angle Mach/CAS and energy optimal) were examined for three traffic mixes represented by those found at Denver Stapleton, John F. Kennedy and typical en route metering (ERM) airports. The Monte Carlo technique was used to generate simulation entry point times. Analysis results indicate that the clean-idle descent strategy offers the best compromise in overall performance. Performance measures primarily include susceptibility to conflict and conflict severity. Fuel usage performance is extrapolated from previous descent strategy studies.

  18. 40 CFR 1066.625 - Flow meter calibration calculations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to calculate viscosities of gas mixtures. b The model results are valid only for ambient conditions..., including a polynomial or a power series. The following equation is an example of a commonly used... each combination of venturis as one venturi by determining K v for the system. (1) To determine K v for...

  19. Excitation condition analysis of guided wave on PFA tubes for ultrasonic flow meter.

    PubMed

    Li, Xuan; Xiao, Xufeng; Cao, Li

    2016-12-01

    Impurity accumulation, which decreases the accuracy of flow measurement, is a critical problem when applying Z-shaped or U-shaped ultrasonic flow meters on straight PFA tubes. It can be expected that the guided wave can be used to implement flow measurement on straight PFA tubes. In this paper, the propagation of guided wave is explained by finite element simulations for the flow meter design. Conditions of guided wave generation, including the excitation frequency and the wedge structure, are studied in the simulations. The wedge is designed as a cone which is friendly to be manufactured and installed. The cone angle, the piezoelectric wafer's resonant frequency and the vibration directions are studied in the simulations. The simulations shows that the propagation of guided wave in thin PFA tubes is influenced by the piezoelectric wafers' resonant frequency and the vibration direction when the mode is on the 'water line'. Based on the results of the simulations, an experiment is conducted to verify the principles of excitation conditions, which performs flow measurement on a straight PFA tube well. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. A portable meter for measuring low frequency currents in the human body.

    PubMed

    Niple, J C; Daigle, J P; Zaffanella, L E; Sullivan, T; Kavet, R

    2004-07-01

    A portable meter has been developed for measuring low frequency currents that flow in the human body. Although the present version of the meter was specifically designed to measure 50/60 Hz "contact currents," the principles involved can be used with other low frequency body currents. Contact currents flow when the human body provides a conductive path between objects in the environment with different electrical potentials. The range of currents the meter detects is approximately 0.4-800 microA. This provides measurements of currents from the threshold of human perception (approximately 500 microA(RMS)) down to single microampere levels. The meter has a unique design, which utilizes the human subject's body impedance as the sensing element. Some of the advantages of this approach are high sensitivity, the ability to measure current flow in the majority of the body, and relative insensitivity to the current path connection points. Current measurement accuracy varies with the accuracy of the body impedance (resistance) measurement and different techniques can be used to obtain a desired level of accuracy. Techniques are available to achieve an estimated +/-20% accuracy. Copyright 2004 Wiley-Liss, Inc.

  1. Calibrating/testing meters in hot water test bench VM7

    NASA Astrophysics Data System (ADS)

    Kling, E.; Stolt, K.; Lau, P.; Mattiasson, K.

    A Hot Water Test Bench, VM7, has been developed and constructed for the calibration and testing of volume and flowmeters, in a project at the National Volume Measurement Laboratory at the Swedish National Testing and Research Institute. The intended area of use includes use as a reference at audit measurements, e.g. for accredited laboratories, calibration of meters for the industry and for the testing of hot water meters. The objective of the project, which was initiated in 1989, was to design equipment with stable flow and with a minimal temperature drop even at very low flow rates. The principle of the design is a closed system with two pressure tanks at different pressures. The water is led from the high pressure tank through the test object and the volume standard, in the form of master meters or a piston prover alternatively, to the low pressure tank. Calibrations/tests are made comparing the indication of the test object to that of master meters covering the current flow rate. These are, in the same test cycle, calibrated to the piston prover. Alternatively, the test object can be calibrated directly to the piston prover.

  2. Fuel supply device for supplying fuel to an engine combustor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lindsay, M.H.; Kerr, W.B.

    1990-05-29

    This patent describes a variable flow rate fuel supply device for supplying fuel to an engine combustor. It comprises: fuel metering means having a fuel valve means for controlling the flow rate of fuel to the combustor; piston means for dividing a first cooling fluid chamber from a second cooling fluid chamber; coupling means for coupling the piston means to the fuel valve means; and cooling fluid supply means in communication with the first and second cooling fluid chamber for producing a first pressure differential across the piston means for actuating the fuel valve means in a first direction, andmore » for producing a second pressure differential across the piston means for actuating the valve means in a second direction opposite the first direction, to control the flow rate of the fuel through the fuel metering means and into the engine combustor; and means for positioning the fuel metering means within the second cooling air chamber enabling the cooling air supply means to both cool the fuel metering means and control the fuel supply rate of fuel supplied by the fuel metering means to the combustor.« less

  3. Experimentally Modeling Black and White Hole Event Horizons via Fluid Flow

    NASA Astrophysics Data System (ADS)

    Manheim, Marc E.; Lindner, John F.; Manz, Niklas

    We will present a scaled down experiment that hydrodynamically models the interaction between electromagnetic waves and black/white holes. It has been mathematically proven that gravity waves in water can behave analogously to electromagnetic waves traveling through spacetime. In this experiment, gravity waves will be generated in a water tank and propagate in a direction opposed to a flow of varying rate. We observe a noticeable change in the wave's spreading behavior as it travels through the simulated horizon with decreased wave speeds up to standing waves, depending on the opposite flow rate. Such an experiment has already been performed in a 97.2 cubic meter tank. We reduced the size significantly to be able to perform the experiment under normal lab conditions.

  4. Analysis of Geomorphic and Hydrologic Characteristics of Mount Jefferson Debris Flow, Oregon, November 6, 2006

    USGS Publications Warehouse

    Sobieszczyk, Steven; Uhrich, Mark A.; Piatt, David R.; Bragg, Heather M.

    2008-01-01

    On November 6, 2006, a rocky debris flow surged off the western slopes of Mount Jefferson into the drainage basins of Milk and Pamelia Creeks in Oregon. This debris flow was not a singular event, but rather a series of surges of both debris and flooding throughout the day. The event began during a severe storm that brought warm temperatures and heavy rainfall to the Pacific Northwest. Precipitation measurements near Mount Jefferson at Marion Forks and Santiam Junction showed that more than 16.1 centimeters of precipitation fell the week leading up to the event, including an additional 20.1 centimeters falling during the 2 days afterward. The flooding associated with the debris flow sent an estimated 15,500 to 21,000 metric tons, or 9,800 to 13,000 cubic meters, of suspended sediment downstream, increasing turbidity in the North Santiam River above Detroit Lake to an estimated 35,000 to 55,000 Formazin Nephelometric Units. The debris flow started small as rock and ice calved off an upper valley snowfield, but added volume as it eroded weakly consolidated deposits from previous debris flows, pyroclastic flows, and glacial moraines. Mud run-up markings on trees indicated that the flood stage of this event reached depths of at least 2.4 meters. Velocity calculations indicate that different surges of debris flow and flooding reached 3.9 meters per second. The debris flow reworked and deposited material ranging in size from sand to coarse boulders over a 0.1 square kilometer area, while flooding and scouring as much as 0.45 square kilometer. Based on cross-sectional transect measurements recreating pre-event topography and other field measurements, the total volume of the deposit ranged from 100,000 to 240,000 cubic meters.

  5. 40 CFR 1033.525 - Smoke testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... measure smoke emissions using a full-flow, open path light extinction smokemeter. A light extinction meter... path length equal to the hydraulic diameter. The light extinction meter must meet the requirements of... apertures (or windows and lenses) and on the axis of the light beam. (8) You may use light extinction meters...

  6. 40 CFR 1033.525 - Smoke testing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... measure smoke emissions using a full-flow, open path light extinction smokemeter. A light extinction meter... path length equal to the hydraulic diameter. The light extinction meter must meet the requirements of... apertures (or windows and lenses) and on the axis of the light beam. (8) You may use light extinction meters...

  7. 40 CFR 1033.525 - Smoke testing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... measure smoke emissions using a full-flow, open path light extinction smokemeter. A light extinction meter... path length equal to the hydraulic diameter. The light extinction meter must meet the requirements of... apertures (or windows and lenses) and on the axis of the light beam. (8) You may use light extinction meters...

  8. 40 CFR 1033.525 - Smoke testing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... measure smoke emissions using a full-flow, open path light extinction smokemeter. A light extinction meter... path length equal to the hydraulic diameter. The light extinction meter must meet the requirements of... apertures (or windows and lenses) and on the axis of the light beam. (8) You may use light extinction meters...

  9. Highlights of the high-temperature falling particle receiver project: 2012 - 2016

    NASA Astrophysics Data System (ADS)

    Ho, C. K.; Christian, J.; Yellowhair, J.; Jeter, S.; Golob, M.; Nguyen, C.; Repole, K.; Abdel-Khalik, S.; Siegel, N.; Al-Ansary, H.; El-Leathy, A.; Gobereit, B.

    2017-06-01

    A 1 MWt continuously recirculating falling particle receiver has been demonstrated at Sandia National Laboratories. Free-fall and obstructed-flow receiver designs were tested with particle mass flow rates of ˜1 - 7 kg/s and average irradiances up to 1,000 suns. Average particle outlet temperatures exceeded 700 °C for the free-fall tests and reached nearly 800 °C for the obstructed-flow tests, with peak particle temperatures exceeding 900 °C. High particle heating rates of ˜50 to 200 °C per meter of illuminated drop length were achieved for the free-fall tests with mass flow rates ranging from 1 - 7 kg/s and for average irradiances up to ˜ 700 kW/m2. Higher temperatures were achieved at the lower particle mass flow rates due to less shading. The obstructed-flow design yielded particle heating rates over 300 °C per meter of illuminated drop length for mass flow rates of 1 - 3 kg/s for irradiances up to ˜1,000 kW/m2. The thermal efficiency was determined to be ˜60 - 70% for the free-falling particle tests and up to ˜80% for the obstructed-flow tests. Challenges encountered during the tests include particle attrition and particle loss through the aperture, reduced particle mass flow rates at high temperatures due to slot aperture narrowing and increased friction, and deterioration of the obstructed-flow structures due to wear and oxidation. Computational models were validated using the test data and will be used in future studies to design receiver configurations that can increase the thermal efficiency.

  10. Recessed impingement insert metering plate for gas turbine nozzles

    DOEpatents

    Itzel, Gary Michael; Burdgick, Steven Sebastian

    2002-01-01

    An impingement insert sleeve is provided that is adapted to be disposed in a coolant cavity defined through a stator vane. The insert has a generally open inlet end and first and second diametrically opposed, perforated side walls. A metering plate having at least one opening defined therethrough for coolant flow is mounted to the side walls to generally transverse a longitudinal axis of the insert, and is disposed downstream from said inlet end. The metering plate improves flow distribution while reducing ballooning stresses within the insert and allowing for a more flexible insert attachment.

  11. Evaluation of a hemispherical head flow direction sensor for inlet duct measurements

    NASA Technical Reports Server (NTRS)

    Bennett, D. L.

    1975-01-01

    A hemispherical head flow direction sensor was tested in a wind tunnel to evaluate its effectiveness for measuring dynamic duct flow direction angles of plus and minus 27 degrees. The tests were conducted at Reynolds numbers of 3.8 million per meter (1.0 million per foot) and 4.92 million per meter (1.5 million per foot) and at Mach numbers from 0.30 to 0.70. The design criteria for the probe are discussed and the wind tunnel results are presented. Three techniques for deriving the flow angles are described.

  12. Note: Void effects on eddy current distortion in two-phase liquid metal.

    PubMed

    Kumar, M; Tordjeman, Ph; Bergez, W; Cavaro, M

    2015-10-01

    A model based on the first order perturbation expansion of magnetic flux in a two-phase liquid metal flow has been developed for low magnetic Reynolds number Rem. This model takes into account the distortion of the induced eddy currents due to the presence of void in the conducting medium. Specific experiments with an eddy current flow meter have been realized for two periodic void distributions. The results have shown, in agreement with the model, that the effects of velocity and void on the emf modulation are decoupled. The magnitude of the void fraction and the void spatial frequency can be determined from the spectral density of the demodulated emf.

  13. Examination of magnetic resonance soundings in the Central Platter River Basin for ground water model enhancements

    NASA Astrophysics Data System (ADS)

    Abraham, J. D.; Kress, W. H.; Cannia, J. C.; Steele, G. V.; Smith, B. D.; Woodward, D.

    2008-12-01

    In 2007, the USGS in cooperation with the Central Platte Natural Resources District, central Nebraska, initiated a four year study to test the usefulness of magnetic resonance rounding (MRS) to gather information on aquifer characteristics. Magnetic resonance sounding is a ground surface applied tool which has the potential to measure hydraulic conductivity at depth using noninvasive means. This in turn will provide a low cost alternative to traditional aquifer tests. MRS also will allow for collection of large data sets of aquifer properties during short periods of time. The work is under way in Dawson County near Lexington, Nebraska to characterize the hydrogeology of the Quaternary-age alluvial and underlying Tertiary-age Ogallala Group aquifers that occur within the Platte River Valley. This county was selected because it lies in an area of Nebraska that has major groundwater- surface water management issues which have stimulated the development of regional and local groundwater models. Data used to evaluate the MRS during this study were derived from traditional constant discharge aquifer tests, borehole flow meter tests, lithologic descriptions, borehole geophysics, and time-domain electromagnetic soundings. This study presents methods and interpretation of MRS. The MRS-derived hydraulic conductivity data will be compared to hydraulic conductivity data from two separate constant discharge pumping tests of the alluvium and Ogallala Group aquifers at Site 72 The MRS-derived hydraulic conductivity data will also be compared to conductivity estimates based on data from a borehole flow meter test. This information can potentially be incorporated into groundwater models of the area to provide improved data sets of aquifer characteristics. The research will document an integrated MRS, surface geophysical, borehole geophysical, borehole flow meter and aquifer test approach in which the hydrostratigraphy of the Platte River alluvial aquifer and Ogallala aquifer can be described.

  14. Saturn Northern Hemisphere

    NASA Image and Video Library

    1998-12-05

    This false color picture of Saturn’s northern hemisphere was assembled from ultraviolet, violet and green images obtained Aug. 19 by Voyager 2 from a range of 7.1 million kilometers (4.4 million miles). The several weather patterns evident include three spots flowing westward at about 15 meters-per-second (33 mph). Although the cloud system associated with the western-most spot is part of this flow, the spot itself moves eastward at about 30 meters-per-second (65 mph). Their joint flow shows the anti-cyclonic rotation of the spot, which is about 3,000 km. (1,900 mi.) in diameter. The ribbon- like feature to the north marks a high-speed jet where wind speeds approach 150 meters-per-second (330 mph). http://photojournal.jpl.nasa.gov/catalog/PIA01365

  15. A physics based multiscale modeling of cavitating flows.

    PubMed

    Ma, Jingsen; Hsiao, Chao-Tsung; Chahine, Georges L

    2017-03-02

    Numerical modeling of cavitating bubbly flows is challenging due to the wide range of characteristic lengths of the physics at play: from micrometers (e.g., bubble nuclei radius) to meters (e.g., propeller diameter or sheet cavity length). To address this, we present here a multiscale approach which integrates a Discrete Singularities Model (DSM) for dispersed microbubbles and a two-phase Navier Stokes solver for the bubbly medium, which includes a level set approach to describe large cavities or gaseous pockets. Inter-scale schemes are used to smoothly bridge the two transitioning subgrid DSM bubbles into larger discretized cavities. This approach is demonstrated on several problems including cavitation inception and vapor core formation in a vortex flow, sheet-to-cloud cavitation over a hydrofoil, cavitation behind a blunt body, and cavitation on a propeller. These examples highlight the capabilities of the developed multiscale model in simulating various form of cavitation.

  16. A physics based multiscale modeling of cavitating flows

    PubMed Central

    Ma, Jingsen; Hsiao, Chao-Tsung; Chahine, Georges L.

    2018-01-01

    Numerical modeling of cavitating bubbly flows is challenging due to the wide range of characteristic lengths of the physics at play: from micrometers (e.g., bubble nuclei radius) to meters (e.g., propeller diameter or sheet cavity length). To address this, we present here a multiscale approach which integrates a Discrete Singularities Model (DSM) for dispersed microbubbles and a two-phase Navier Stokes solver for the bubbly medium, which includes a level set approach to describe large cavities or gaseous pockets. Inter-scale schemes are used to smoothly bridge the two transitioning subgrid DSM bubbles into larger discretized cavities. This approach is demonstrated on several problems including cavitation inception and vapor core formation in a vortex flow, sheet-to-cloud cavitation over a hydrofoil, cavitation behind a blunt body, and cavitation on a propeller. These examples highlight the capabilities of the developed multiscale model in simulating various form of cavitation. PMID:29720773

  17. Evaluation of a simplified gross thrust calculation technique using two prototype F100 turbofan engines in an altitude facility

    NASA Technical Reports Server (NTRS)

    Kurtenbach, F. J.

    1979-01-01

    The technique which relies on afterburner duct pressure measurements and empirical corrections to an ideal one dimensional flow analysis to determine thrust is presented. A comparison of the calculated and facility measured thrust values is reported. The simplified model with the engine manufacturer's gas generator model are compared. The evaluation was conducted over a range of Mach numbers from 0.80 to 2.00 and at altitudes from 4020 meters to 15,240 meters. The effects of variations in inlet total temperature from standard day conditions were explored. Engine conditions were varied from those normally scheduled for flight. The technique was found to be accurate to a twice standard deviation of 2.89 percent, with accuracy a strong function of afterburner duct pressure difference.

  18. 40 CFR 1066.140 - Diluted exhaust flow calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... whenever corrective action does not resolve a failure to meet the diluted exhaust flow verification (i.e... subsonic venturi flow meter, a long-radius ASME/NIST flow nozzle, a smooth approach orifice, a laminar flow...

  19. Changes to subaqueous delta bathymetry following a high river flow event, Wax Lake Delta, LA, USA

    NASA Astrophysics Data System (ADS)

    Whaling, A. R.; Shaw, J.

    2017-12-01

    Sediment transport capacity is increased during high river flow (flood) events which are characterized by discharges that exceed the 15 year median daily statistic. The Wax Lake Delta (WLD) in coastal Louisiana has experienced 19 of these high flow events in the past 20 years, yet the depositional patterns of single floods are rarely measured in a field-scale deltaic setting. We characterize flood deposition and erosion patterns on the subaqueous portion of the WLD by differencing two Digital Elevation Models (DEMs) constructed from bathymetric surveys before and after the third largest flood in the WLD's recorded history. The total suspended sediment discharge for the 496 day inter-survey period was 2.14x107 cubic meters measured 21 km upstream of the delta apex. The difference map showed 1.06x107 cubic meters of sediment was deposited and 8.2x106 cubic meters was eroded, yielding 2.40x106 cubic meters of net deposition in the survey area ( 79.7 km2 ). Therefore the average deposition rate was 0.061 mm/day. Channel planform remained relatively unchanged for five out of six distributary passes however Gadwall Pass experienced a maximum channel displacement of 166 m ( 1 channel width) measured from the thalweg centerline. Channel tip extension was negligible. In addition, channel displacement was not concentrated at any portion along the channel centerline. Maximum erosion occurred within channel margins and increased upstream whereas maximum deposition occurred immediately outside the channel margins. Sediment eroded from the survey area was either subsequently re-deposited or transported out of the system. Our results show that up to 77.4% of deposition in the survey area originated from sediment eroded during the flood. Surprisingly, only 11.2% of the total suspended sediment discharge was retained in the subaqueous portion of the delta after the flood. We conclude that a high flow event does not produce channel progradation. Rather, high flow causes delta aggradation and channel incision. The role of increased sediment supply versus erosive capabilities during high flow is roughly comparable regarding changes to subaqueous delta bathymetry. These counterintuitive results have important implications for land building from sediment diversions and stratigraphic analysis of deltas.

  20. Density and Cavitating Flow Results from a Full-Scale Optical Multiphase Cryogenic Flowmeter

    NASA Technical Reports Server (NTRS)

    Korman, Valentin

    2007-01-01

    Liquid propulsion systems are hampered by poor flow measurements. The measurement of flow directly impacts safe motor operations, performance parameters as well as providing feedback from ground testing and developmental work. NASA Marshall Space Flight Center, in an effort to improve propulsion sensor technology, has developed an all optical flow meter that directly measures the density of the fluid. The full-scale sensor was tested in a transient, multiphase liquid nitrogen fluid environment. Comparison with traditional density models shows excellent agreement with fluid density with an error of approximately 0.8%. Further evaluation shows the sensor is able to detect cavitation or bubbles in the flow stream and separate out their resulting effects in fluid density.

  1. Expanding the Use of Time-Based Metering: Multi-Center Traffic Management Advisor

    NASA Technical Reports Server (NTRS)

    Landry, Steven J.; Farley, Todd; Hoang, Ty

    2005-01-01

    Time-based metering is an efficient air traffic management alternative to the more common practice of distance-based metering (or "miles-in-trail spacing"). Despite having demonstrated significant operational benefit to airspace users and service providers, time-based metering is used in the United States for arrivals to just nine airports and is not used at all for non-arrival traffic flows. The Multi-Center Traffic Management Advisor promises to bring time-based metering into the mainstream of air traffic management techniques. Not constrained to operate solely on arrival traffic, Multi-Center Traffic Management Advisor is flexible enough to work in highly congested or heavily partitioned airspace for any and all traffic flows in a region. This broader and more general application of time-based metering is expected to bring the operational benefits of time-based metering to a much wider pool of beneficiaries than is possible with existing technology. It also promises to facilitate more collaborative traffic management on a regional basis. This paper focuses on the operational concept of the Multi-Center Traffic Management Advisor, touching also on its system architecture, field test results, and prospects for near-term deployment to the United States National Airspace System.

  2. Probability and volume of potential postwildfire debris flows in the 2012 High Park Burn Area near Fort Collins, Colorado

    USGS Publications Warehouse

    Verdin, Kristine L.; Dupree, Jean A.; Elliott, John G.

    2012-01-01

    This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 High Park fire near Fort Collins in Larimer County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volume of debris flows along the burned area drainage network and to estimate the same for 44 selected drainage basins along State Highway 14 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall (25 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall (43 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall (51 millimeters). Estimated debris-flow probabilities along the drainage network and throughout the drainage basins of interest ranged from 1 to 84 percent in response to the 2-year-recurrence, 1-hour-duration rainfall; from 2 to 95 percent in response to the 10-year-recurrence, 1-hour-duration rainfall; and from 3 to 97 in response to the 25-year-recurrence, 1-hour-duration rainfall. Basins and drainage networks with the highest probabilities tended to be those on the eastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Estimated debris-flow volumes range from a low of 1,600 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce substantial volumes of material. The predicted probabilities and some of the volumes predicted for the modeled storms indicate a potential for substantial debris-flow impacts on structures, roads, bridges, and culverts located both within and immediately downstream from the burned area. Colorado State Highway 14 is also susceptible to impacts from debris flows.

  3. Gas compression in lungs decreases peak expiratory flow depending on resistance of peak flowmeter.

    PubMed

    Pedersen, O F; Pedersen, T F; Miller, M R

    1997-11-01

    It has recently been shown (O. F. Pedersen T. R. Rasmussen, O. Omland, T. Sigsgaard, P. H. Quanjer. and M. R. Miller. Eur. Respir. J. 9: 828-833, 1996) that the added resistance of a mini-Wright peak flowmeter decreases peak expiratory flow (PEF) by approximately 8% compared with PEF measured by a pneumotachograph. To explore the reason for this, 10 healthy men (mean age 43 yr, range 33-58 yr) were examined in a body plethysmograph with facilities to measure mouth flow vs. expired volume as well as the change in thoracic gas volume (Vb) and alveolar pressure (PA). The subjects performed forced vital capacity maneuvers through orifices of different sizes and also a mini-Wright peak flowmeter. PEF with the meter and other added resistances were achieved when flow reached the perimeter of the flow-Vb curves. The mini-Wright PEF meter decreased PEF from 11.4 +/- 1.5 to 10.3 +/- 1.4 (SD) l/s (P < 0.001), PA increased from 6.7 +/- 1.9 to 9.3 +/- 2.7 kPa (P < 0.001), an increase equal to the pressure drop across the meter, and caused Vb at PEF to decrease by 0.24 +/- 0.09 liter (P < 0.001). We conclude that PEF obtained with an added resistance like a mini-Wright PEF meter is a wave-speed-determined maximal flow, but the added resistance causes gas compression because of increased PA at PEF. Therefore, Vb at PEF and, accordingly, PEF decrease.

  4. Liquid Oxygen/Liquid Methane Test Results of the RS-18 Lunar Ascent Engine at Simulated Altitude Conditions at NASA White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Melcher, John C., IV; Allred, Jennifer K.

    2009-01-01

    Tests were conducted with the RS-18 rocket engine using liquid oxygen (LO2) and liquid methane (LCH4) propellants under simulated altitude conditions at NASA Johnson Space Center White Sands Test Facility (WSTF). This project is part of NASA's Propulsion and Cryogenics Advanced Development (PCAD) project. "Green" propellants, such as LO2/LCH4, offer savings in both performance and safety over equivalently sized hypergolic propulsion systems in spacecraft applications such as ascent engines or service module engines. Altitude simulation was achieved using the WSTF Large Altitude Simulation System, which provided altitude conditions equivalent up to 122,000 ft (37 km). For specific impulse calculations, engine thrust and propellant mass flow rates were measured. LO2 flow ranged from 5.9 - 9.5 lbm/sec (2.7 - 4.3 kg/sec), and LCH4 flow varied from 3.0 - 4.4 lbm/sec (1.4 - 2.0 kg/sec) during the RS-18 hot-fire test series. Propellant flow rate was measured using a coriolis mass-flow meter and compared with a serial turbine-style flow meter. Results showed a significant performance measurement difference during ignition startup due to two-phase flow effects. Subsequent cold-flow testing demonstrated that the propellant manifolds must be adequately flushed in order for the coriolis flow meters to give accurate data. The coriolis flow meters were later shown to provide accurate steady-state data, but the turbine flow meter data should be used in transient phases of operation. Thrust was measured using three load cells in parallel, which also provides the capability to calculate thrust vector alignment. Ignition was demonstrated using a gaseous oxygen/methane spark torch igniter. Test objectives for the RS-18 project are 1) conduct a shakedown of the test stand for LO2/methane lunar ascent engines, 2) obtain vacuum ignition data for the torch and pyrotechnic igniters, and 3) obtain nozzle kinetics data to anchor two-dimensional kinetics codes. All of these objectives were met with the RS-18 data and additional testing data from subsequent LO2/methane test programs in 2009 which included the first simulated-altitude pyrotechnic ignition demonstration of LO2/methane.

  5. Analysis of inflated submarine and sub-lacustrine Pahoehoe lava flows using high-resolution bathymetric and lidar data (Invited)

    NASA Astrophysics Data System (ADS)

    Deschamps, A.; Van Vliet-Lanoe, B.; Soule, S. A.; Allemand, P.; Le Saout, M.; Delacourt, C.

    2013-12-01

    The summit of the East Pacific Rise (EPR), 16°N, is investigated based -among others- on high-resolution bathymetry acquired using the AUV Aster-X, and photos and videos collected using the submersible Nautile (Ifremer). HR bathymetry reveals submarine tumuli and inflated smooth lava flows at the summit of the ridge, emplaced on sub-horizontal terrains. They are primarily composed of jumbled and lobate flows with occurrences of sheet flows, and pillows close to the flow margins. They are 5 to 15 meters -high, and their surface ranges 0.2 to 1.5 km2. Their surface is either planar or depressed, likely due to lava topographic downdraining during eruption. At their margins, planar slabs of lava, few meters wide, slope down from the top of the flow, at angles ranging 40 to 80°. A series of cracks, 0,5 to 1.5 m deep, separate the horizontal surface of the flow from their inclined flanks. These cracks parallel the sinuous edges of the flows, suggesting the flow flanks tilted outward. Tumuli are also observed. Some of these smooth flows form 80 to 750 m -long sinuous ridges, suggesting the existence of lava tubes. Their morphology indicates that these flows experienced inflationary emplacement styles, but at a much larger scale than Pahoehoe lavas in Hawaii and La Réunion Islands. In these two islands, indeed, inflation structures are typically less than 2 meters high and only several tens of meters in length at maximum, suggesting that their mechanism of emplacement and inflation is significantly different. Conversely, we observe comparable inflation flows in Iceland and in Idaho and Oregon, also emplaced onto sub-horizontal terrains. We use high-resolution aerial photographs and lidar data to investigate their morphology. In the Eastern Snake River Plain (ESRP), quaternary basaltic plains volcanism produced monogenetic coalescent shields, and phreatomagmatic basaltic eruptions that are directly related to proximity of magmatism to the Snake River or Pleistocene lakes. For example, the Hells Half Acres Holocene lava flows, Idaho, display similar morphology as EPR flows, with sheet lavas, flow lobes 5-8 m high and approximately 100 m wide, and pressure ridges. Similar flows are observed in the ESRP: Craters of the Moon, Wapi, and Cerro Grande lava flows for example. In Oregon, Potholes, Devils Garden, Diamond Craters, Deschute River, Owyhee River, Jordan Crater flows are also strictly comparable. In Iceland, Lake Mytvan lava flows, for example, were emplaced in sublacustrine environments, and Budahraun flows in Snaefellness were emplaced at the coast below the sea level. The common point of these presently "aerial" lava flow is their emplacement in lakes, paleo-lakes and river beds, thus in "wet" environment, often controlled by rivers and their tributaries. A more efficient cooling of the lava lobes in wet environment probably triggers the development of strong and plastic margins due to cooling, which resists continued movement of the flow, whereas a thinner margin developing in aerial environment may favor lobe break out when internal pressure rises above the tensile strength of the crust. We propose a theoretical model for these lava flow emplacement on sub-horizontal basement.

  6. Combined use of thermal methods and seepage meters to efficiently locate, quantify, and monitor focused groundwater discharge to a sand-bed stream

    USGS Publications Warehouse

    Rosenberry, Donald O.; Briggs, Martin A.; Delin, Geoffrey N.; Hare, Danielle K.

    2016-01-01

    Quantifying flow of groundwater through streambeds often is difficult due to the complexity of aquifer-scale heterogeneity combined with local-scale hyporheic exchange. We used fiber-optic distributed temperature sensing (FO-DTS), seepage meters, and vertical temperature profiling to locate, quantify, and monitor areas of focused groundwater discharge in a geomorphically simple sand-bed stream. This combined approach allowed us to rapidly focus efforts at locations where prodigious amounts of groundwater discharged to the Quashnet River on Cape Cod, Massachusetts, northeastern USA. FO-DTS detected numerous anomalously cold reaches one to several m long that persisted over two summers. Seepage meters positioned upstream, within, and downstream of 7 anomalously cold reaches indicated that rapid groundwater discharge occurred precisely where the bed was cold; median upward seepage was nearly 5 times faster than seepage measured in streambed areas not identified as cold. Vertical temperature profilers deployed next to 8 seepage meters provided diurnal-signal-based seepage estimates that compared remarkably well with seepage-meter values. Regression slope and R2 values both were near 1 for seepage ranging from 0.05 to 3.0 m d−1. Temperature-based seepage model accuracy was improved with thermal diffusivity determined locally from diurnal signals. Similar calculations provided values for streambed sediment scour and deposition at subdaily resolution. Seepage was strongly heterogeneous even along a sand-bed river that flows over a relatively uniform sand and fine-gravel aquifer. FO-DTS was an efficient method for detecting areas of rapid groundwater discharge, even in a strongly gaining river, that can then be quantified over time with inexpensive streambed thermal methods.

  7. Deployable Emergency Shutoff Device Blocks High-Velocity Fluid Flows

    NASA Technical Reports Server (NTRS)

    Nabors, Sammy A.

    2015-01-01

    NASA's Marshall Space Flight Center has developed a device and method for blocking the flow of fluid from an open pipe. Motivated by the sea-bed oil-drilling catastrophe in the Gulf of Mexico in 2010, NASA innovators designed the device to plug, control, and meter the flow of gases and liquids. Anchored with friction fittings, spikes, or explosively activated fasteners, the device is well-suited for harsh environments and high fluid velocities and pressures. With the addition of instrumentation, it can also be used as a variable area flow metering valve that can be set based upon flow conditions. With robotic additions, this patent-pending innovation can be configured to crawl into a pipe then anchor and activate itself to block or control fluid flow.

  8. Methods of measurement signal acquisition from the rotational flow meter for frequency analysis

    NASA Astrophysics Data System (ADS)

    Świsulski, Dariusz; Hanus, Robert; Zych, Marcin; Petryka, Leszek

    One of the simplest and commonly used instruments for measuring the flow of homogeneous substances is the rotational flow meter. The main part of such a device is a rotor (vane or screw) rotating at a speed which is the function of the fluid or gas flow rate. A pulse signal with a frequency proportional to the speed of the rotor is obtained at the sensor output. For measurements in dynamic conditions, a variable interval between pulses prohibits the analysis of the measuring signal. Therefore, the authors of the article developed a method involving the determination of measured values on the basis of the last inter-pulse interval preceding the moment designated by the timing generator. For larger changes of the measured value at a predetermined time, the value can be determined by means of extrapolation of the two adjacent interpulse ranges, assuming a linear change in the flow. The proposed methods allow analysis which requires constant spacing between measurements, allowing for an analysis of the dynamics of changes in the test flow, eg. using a Fourier transform. To present the advantages of these methods simulations of flow measurement were carried out with a DRH-1140 rotor flow meter from the company Kobold.

  9. 40 CFR 1065.340 - Diluted exhaust flow (CVS) calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... action does not resolve a failure to meet the diluted exhaust flow verification (i.e., propane check) in... subsonic venturi flow meter, a long-radius ASME/NIST flow nozzle, a smooth approach orifice, a laminar flow...

  10. Open-channel integrating-type flow meter

    USGS Publications Warehouse

    Koopman, K.C.

    1971-01-01

    A relatively inexpensive meter for measuring cumulative flow in open channels with a rated control,. called a "totalizer", was developed. It translates the nonlinear function of gage height to flow by use of a cam and a float. A variable resistance element in an electronic circuit is controlled by the float so that the electron flow in the circuit corresponds to the flow of water. The flow of electricity causes electroplating of an electrode with silver. The amount of silver deposited is proportionate to the flow of water. The total flow of water is determined by removing the silver from the electrode at a fixed rate with ·an electronic device and recording the time for removal with a counter. The circuit is designed so that the ,resultant reading on the counter is in acre-feet of water.

  11. Basal Terraces on Melting Ice Shelves

    NASA Astrophysics Data System (ADS)

    Dutrieux, P.; Stewart, C.; Jenkins, A.; Nicholls, K. W.; Corr, H. F. J.; Rignot, E. J.; Steffen, K.

    2014-12-01

    Ocean waters melt the margins of Antarctic and Greenland glaciers and individualglaciers' responses and the integrity of their ice shelves are expected to depend on thespatial distribution of melt. The bases of the ice shelves associated with Pine IslandGlacier (West Antarctica) and Petermann Glacier (Greenland) have similar geometries,including kilometers-wide, hundreds-of-meter-high channels oriented along and acrossthe direction of ice flow. The channels are enhanced by, and constrain, oceanic melt.New, meter-scale observations of basal topography reveal peculiar glaciated landscapes.Channel flanks are not smooth, but are instead stepped, with hundreds-of-meters-wideflat terraces separated by 5-50 m-high walls. Melting is shown to be modulated by thegeometry: constant across each terrace, changing from one terrace to the next, and greatlyenhanced on the ~45°-inclined walls. Melting is therefore fundamentally heterogeneousand likely associated with stratification in the ice-ocean boundary layer, challengingcurrent models of ice shelf-ocean interactions.

  12. Simulation of ground-water flow, contributing recharge areas, and ground-water travel time in the Missouri River alluvial aquifer near Ft. Leavenworth, Kansas

    USGS Publications Warehouse

    Kelly, Brian P.

    2004-01-01

    The Missouri River alluvial aquifer near Ft. Leavenworth, Kansas, supplies all or part of the drinking water for Ft. Leavenworth; Leavenworth, Kansas; Weston, Missouri; and cooling water for the Kansas City Power and Light, Iatan Power Plant. Ground water at three sites within the alluvial aquifer near the Ft. Leavenworth well field is contaminated with trace metals and organic compounds and concerns have been raised about the potential contamination of drinking-water supplies. In 2001, the U.S. Geological Survey, U.S. Army Corps of Engineers, and the U.S. Army began a study of ground-water flow in the Missouri River alluvial aquifer near Ft. Leavenworth. Hydrogeologic data from 173 locations in the study area was used to construct a ground-water flow model (MODFLOW-2000) and particle-tracking program (MODPATH) to determine the direction and travel time of ground-water flow and contributing recharge areas for water-supply well fields within the alluvial aquifer. The modeled area is 28.6 kilometers by 32.6 kilometers and contains the entire study area. The model uses a uniform grid size of 100 meters by 100 meters and contains 372,944 cells in 4 layers, 286 columns, and 326 rows. The model represents the alluvial aquifer using four layers of variable thickness with no intervening confining layers. The model was calibrated to both quasi-steady-state and transient hydraulic head data collected during the study and ground-water flow was simulated for five well-pumping/river-stage scenarios. The model accuracy was calculated using the root mean square error between actual measurements of hydraulic head and model generated hydraulic head at the end of each model run. The accepted error for the model calibrations were below the maximum measurement errors. The error for the quasi-steady-state calibration was 0.82 meter; for the transient calibration it was 0.33 meter. The shape, size, and ground-water travel time within the contributing recharge area for each well or well field is affected by changes in river stage and pumping rates and by the location of the well or well field with respect to the major rivers, alluvial valley walls, and other pumping wells. The shapes of the simulated contributing recharge areas for the well fields in the study area are elongated in the upstream direction for all well-pumping/river-stage scenarios. The capture of ground water by the pumping wells as it moved downgradient toward the Missouri River caused the long up-valley extent of the contributing recharge areas. Recharge to the Iatan and Weston well fields primarily is from precipitation and surface runoff from the surrounding uplands because the contributing recharge area does not intersect the Missouri River for any well-pumping/river-stage scenarios. Recharge to the Leavenworth and Ft. Leavenworth well fields is from precipitation, surface runoff from the surrounding uplands, and the Missouri River because the contributing recharge area intersects these boundaries for all well-pumping/river-stage scenarios. Particle tracking analysis indicated ground water from the three contaminated sites was captured by the Ft. Leavenworth well field for all well-pumping/river-stage scenarios. Ground-water travel times to the Ft. Leavenworth well field for average well-pumping/river-stage scenario ranged from about 33 years for the closest contamination site to about 71 years for the farthest contamination site. Ground-water flow was induced below the Missouri River by the Ft. Leavenworth and Leavenworth well fields for all well-pumping/river-stage scenarios.

  13. Water flow measurement in large bore pipes: an experimental comparison between two different types of insertion flowmeters.

    PubMed

    Cascetta, Furio; Palombo, Adolfo; Scalabrini, Gianfranco

    2003-04-01

    In this paper the metrological behavior of two different insertion flowmeters (magnetic and turbine types) in large water pipes is described. A master-slave calibration was carried out in order to estimate the overall uncertainty of the tested meters. The experimental results show that (i) the magnetic insertion tested flowmeter performs the claimed accuracy (+/- 2%) within all the flow range (20:1); (ii) the insertion turbine tested meter, instead, reaches the claimed accuracy just in the upper zone of the flow range.

  14. STORM-SEWER FLOW MEASUREMENT AND RECORDING SYSTEM.

    USGS Publications Warehouse

    Kilpatrick, Frederick A.; Kaehrle, William R.

    1986-01-01

    A comprehensive study and development of instruments and techniques for measuring all components of flow in a storm-sewer drainage system were undertaken by the U. S. Geological Survey under the sponsorship of FHWA. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, and electromagnetic velocity meters as well as the development and calibration of pneumatic bubbler and pressure transducer head-measuring systems. Tracer dilution and acoustic-flowmeter measurements were used in field verification tests. A single micrologger was used to record data from all the instruments and also to activate on command the electromagnetic velocity meter and tracer dilution systems.

  15. Earth observations taken from Space Shuttle Columbia during STS-80 mission

    NASA Image and Video Library

    1996-11-30

    STS080-733-001 (19 Nov.-7 Dec. 1996) --- This view shows Mount Everest, near the border of Nepal and China, which reaches 29,028 feet in elevation (8,848 meters). Mount Everest is to the left of the V-shaped valley (holding picture with numbers on the right). Tibet is to the right, and Nepal is below. Rongbuk Glacier flows to the north while Khumbu Glacier flows to the south from Mount Everest. Many other glaciers are visible. The snow level is about 4,000 meters south of the divide or rain shadow, and about 6,000 meters north of the divide, in the rain shadow.

  16. Quaternary sedimentary processes on the northwestern African continental margin - An integrated study using side-scan sonar, high-resolution profiling, and core data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Masson, D.G.; Huggett, Q.J.; Weaver, P.P.E.

    1991-08-01

    Side-scan sonar data, cores, and high-resolution profiles have been used to produce an integrated model of sedimentation for the continental margin west of the Canary Islands. Long-range side-scan sonar (GLORIA) data and a grid of 3.5-kHz profiles, covering some 200,000 km{sup 2} allow a regional appraisal of sedimentation. More detailed studies of selected areas have been undertaken using a new 30 kHz deep-towed side-scan sonar (TOBI) developed by the U.K. Institute of Oceanographic Sciences. Sediment cores have been used both to calibrate acoustic facies identified on sonographs and for detailed stratigraphic studies. The most recent significant sedimentation event in themore » area is to Saharan Sediment Slide, which carried material from the upper continental slope off West Africa to the edge of the Madeira Abyssal Plain, a distance of some 1000 km. The authors data shows the downslope evolution of the debris flow. Near the Canaries, it is a 20-m-thick deposit rafting coherent blocks of more than 1 km diameter; side-scan records show a strong flow-parallel fabric on a scale of tens of meters. On the lower slope, the debris flow thins to a few meters, the flow fabric disappears, and the rafted blocks decrease to meters in diameter. Side-scan data from the lower slope show that the Saharan Slide buries an older landscape of turbidity current channels, typically 1 km wide and 50 m deep. Evidence from the Madeiran Abyssal Plain indicates a history of large but infrequent turbidity currents, the emplacement of which is related to the effects of sea level changes on the northwest African margin.« less

  17. Gas flow meter and method for measuring gas flow rate

    DOEpatents

    Robertson, Eric P.

    2006-08-01

    A gas flow rate meter includes an upstream line and two chambers having substantially equal, fixed volumes. An adjustable valve may direct the gas flow through the upstream line to either of the two chambers. A pressure monitoring device may be configured to prompt valve adjustments, directing the gas flow to an alternate chamber each time a pre-set pressure in the upstream line is reached. A method of measuring the gas flow rate measures the time required for the pressure in the upstream line to reach the pre-set pressure. The volume of the chamber and upstream line are known and fixed, thus the time required for the increase in pressure may be used to determine the flow rate of the gas. Another method of measuring the gas flow rate uses two pressure measurements of a fixed volume, taken at different times, to determine the flow rate of the gas.

  18. Low speed wind tunnel test of a propulsive wing/canard concept in the STOL configuration. Volume 2: Test data

    NASA Technical Reports Server (NTRS)

    Stewart, V. R.

    1987-01-01

    A propulsive wind/canard model was tested at STOL operating conditions in the NASA Langley Research Center 4 x 7 meter wind tunnel. Longitudinal and lateral/directional aerodynamic characteristics were measured for various flap deflections, angles of attack and sideslip, and blowing coefficients. Testing was conducted for several model heights to determine ground proximity effects on the aerodynamic characteristics. Flow field surveys of local flow angles and velocities were performed behind both the canard and the wing. This is volume 2 of a 2 volume report. All of the test data in three appendices are presented. Appendix A presented tabulated six component force and moment data, Appendix B presents tabulated wing pressure coefficients, and Appendix C presents the flow field data.

  19. Preparation and Characteristics of Ultrasonic Transducers for High Temperature Using PbNb2O6

    NASA Astrophysics Data System (ADS)

    Soejima, Junichiro; Sato, Kokichi; Nagata, Kunihiro

    2000-05-01

    The substance PZT(Pb(Zr, Ti)O3) is chiefly used for piezoceramic transducers in many ultrasonic flow meters. It is difficult to use PZT transducers for flow meters for automobile exhaust gas at high temperatures over 350°C. Lead niobate (PbNb2O6) has a high Curie temperature of 540°C and a low mechanical quality factor, and is the most suitable as the sensor element in flow meters for automobile exhaust gas. However, it is difficult to fabricate dense PbNb2O6 ceramics that have good piezoelectric properties. In this study, ceramics with high density and a high piezoelectric effect were fabricated by adding various elements such as Mn and Ca to PbNb2O6 and by examining the sintering process. A Langevin transducer with a resonance frequency of 80 kHz was made for measuring automobile exhaust gas flow using PbNb2O6 ceramics.

  20. Estimates of bridge scour at two sites on the Virgin River, southeastern Nevada, using a sediment-transport model and historical geomorphic data

    USGS Publications Warehouse

    Hilmes, M.M.; Vaill, J.E.

    1997-01-01

    A bridge-scour study by the U.S. Geological Survey, in cooperation with the Nevada Department of Transportation, began in April 1996 to evaluate the Mesquite, Nevada, and Riverside, Nevada, bridges on the lower Virgin River using a sediment-transport model and historical geomorphic data. The BRIdge Stream Tube model for Alluvial River Simulation (BRI-STARS) was used to estimate bridge scour. The model was first calibrated using data for the Virgin River flood of March 12, 1995. Surveyed channel-geometry data were available at 11 cross sections for dates before and after the March 1995 flood to allow for evaluation of the model results. The model estimated the thalweg altitude within plus or minus 1 meter at 10 of the 11 cross sections. The calibrated model then was used to estimate the contraction, channel, pier, and total scour for synthesized hydrographs for 100- and 500-year floods at the two bridge sites. The estimated maximum total scour at the Mesquite bridge was 1.30 meters for the 100-year flood and 1.32 meters for the 500-year flood. The maximum total scour at the Riverside bridge was 1.90 meters for the 100-year flood and 2.01 meters for the 500-year flood. General scour was evaluated using stage-discharge relations at nearby streamflow-gaging stations, 1993-95 channel-geometry data, and channel-geometry data for the 100- and 500-year floods. On the basis of stage and discharge at the Littlefield, Arizona, gaging station, no long-term trend in aggradation or degradation was found. However, several cycles of aggradation and degradation had occurred during the period of record; the difference between the highest and lowest stage was 0.87 meter for a chosen low-flow discharge of 5.66 cubic meters per second for 1929-95. The value of 0.87 meter is probably the best estimate of general scour. The cross sections had an average scour depth of 0.07 meter between 1993 and 1994 and 0.16 meter between 1994 and 1995. The model simulated little general scour for the 100- and 500-year floods at the cross sections and did not give a good estimate of general scour, probably because the duration (days) of the floods used in the model was relatively short when compared with the duration (months or years) of geomorphic processes that influence long-term aggradation or degradation. Historical geomorphic changes of the Virgin River at the bridge sites and the causes of those changes were documented using aerial photographs from 1938-95 and other historical information. The Virgin River has become narrower and more sinuous through time, the vegetation on the flood plain has increased, and the channel has shifted laterally many times. The processes associated with these channel changes were found to be long-term changes in precipitation and streamflow; the duration, magnitude, and timing of floods; sediment-transport characteristics; channel avulsion; changes in density of vegetation; and anthropogenic influences.

  1. Use of flumes in metering discharge at gaging stations

    USGS Publications Warehouse

    Kilpatrick, F.A.; Schneider, V.R.

    1982-01-01

    Flumes for metering discharge are usually of two general types--critical-flow flumes and supercritical-flow flumes. In this report the principles underlying the design of each are discussed, the most commonly used flumes of each of the two types are described, and discharge ratings for each are presented. Considerations in choosing and fitting the appropriate flume for a given situation are discussed along with construction techniques and operational experiences.

  2. Diagnostic Tools for Performance Evaluation of Innovative In-Situ Remediation Technologies at Chlorinated Solvent-Contaminated Sites

    DTIC Science & Technology

    2011-07-01

    fluid resistivity , temperature logging, and flow metering at other sites that typically indicated only two or three active fractures in each hole...was consistent with results of conventional borehole fluid resistivity , temperature logging, and flow metering at other sites that typically indicated...following tests were performed in each boundary monitoring well: ■ Gamma Ray; ■ Spontaneous Potential (SP); ■ Single Point Resistance (SPR

  3. Measurement Of Multiphase Flow Water Fraction And Water-cut

    NASA Astrophysics Data System (ADS)

    Xie, Cheng-gang

    2007-06-01

    This paper describes a microwave transmission multiphase flow water-cut meter that measures the amplitude attenuation and phase shift across a pipe diameter at multiple frequencies using cavity-backed antennas. The multiphase flow mixture permittivity and conductivity are derived from a unified microwave transmission model for both water- and oil-continuous flows over a wide water-conductivity range; this is far beyond the capability of microwave-resonance-based sensors currently on the market. The water fraction and water cut are derived from a three-component gas-oil-water mixing model using the mixture permittivity or the mixture conductivity and an independently measured mixture density. Water salinity variations caused, for example, by changing formation water or formation/injection water breakthrough can be detected and corrected using an online water-conductivity tracking technique based on the interpretation of the mixture permittivity and conductivity, simultaneously measured by a single-modality microwave sensor.

  4. 40 CFR 1065.330 - Exhaust-flow calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related Measurements § 1065.330... use other reference meters such as laminar flow elements, which are not commonly designed to withstand...

  5. The northern tidal dynamic of Aceh waters: A 3D numerical model

    NASA Astrophysics Data System (ADS)

    Irham, M.; Miswar, E.; Ilhamsyah, Y.; Setiawan, I.

    2018-05-01

    The northern tidal dynamic of Aceh waters studied by employing three-dimensional (3D) numerical hydrodynamic model. The purpose of this study is to understand the phenomena and the characteristic of the northern tidal dynamic of Aceh waters. The research used the explicit-splitting scheme numerical model of Navier-Stokes formulation. The result displays that the vertical rotation of flow movement (vertical eddy) at a depth of 15 to 25 meter eastern part of the study area. Hence, the result also informs that the current circulation identically to the upwelling in the western region of Aceh during the wet season and vice versa. However, during the transitional season, the flow circulation depends on how the tidal dynamic occurs in the area.

  6. Useful method to monitor the physiological effects of alcohol ingestion by combination of micro-integrated laser Doppler blood flow meter and arm-raising test.

    PubMed

    Iwasaki, Wataru; Nogami, Hirofumi; Ito, Hiroki; Gotanda, Takeshi; Peng, Yao; Takeuchi, Satoshi; Furue, Masutaka; Higurashi, Eiji; Sawada, Renshi

    2012-10-01

    Alcohol has a variety of effects on the human body, affecting both the sympathetic and parasympathetic nervous system. We examined the peripheral blood flow of alcohol drinkers using a micro-integrated laser Doppler blood flow meter (micro-electromechanical system blood flow sensor). An increased heart rate and blood flow was recorded at the earlobe after alcohol ingestion, and we observed strong correlation between blood flow, heart rate, and breath alcohol content in light drinkers; but not heavy drinkers. We also found that the amplitude of pulse waves measured at the fingertip during an arm-raising test significantly decreased on alcohol consumption, regardless of the individual's alcohol tolerance. Our micro-electromechanical system blood flow sensor successfully detected various physiological changes in peripheral blood circulation induced by alcohol consumption.

  7. Active bypass flow control for a seal in a gas turbine engine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ebert, Todd A.; Kimmel, Keith D.

    An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wears.more » In at least one embodiment, the metering device may include a valve formed from one or more pins movable between open and closed positions in which the one pin at least partially bisects the bypass channel to regulate flow.« less

  8. Calibration and use of continuous heat-type automated seepage meters for submarine groundwater discharge measurements

    USGS Publications Warehouse

    Mwashote, B.M.; Burnett, W.C.; Chanton, J.; Santos, I.R.; Dimova, N.; Swarzenski, P.W.

    2010-01-01

    Submarine groundwater discharge (SGD) assessments were conducted both in the laboratory and at a field site in the northeastern Gulf of Mexico, using a continuous heat-type automated seepage meter (seepmeter). The functioning of the seepmeter is based on measurements of a temperature gradient in the water between downstream and upstream positions in its flow pipe. The device has the potential of providing long-term, high-resolution measurements of SGD. Using a simple inexpensive laboratory set-up, we have shown that connecting an extension cable to the seepmeter has a negligible effect on its measuring capability. Similarly, the observed influence of very low temperature (???3 ??C) on seepmeter measurements can be accounted for by conducting calibrations at such temperatures prior to field deployments. Compared to manual volumetric measurements, calibration experiments showed that at higher water flow rates (>28 cm day-1 or cm3 cm-2 day-1) an analog flowmeter overestimated flow rates by ???7%. This was apparently due to flow resistance, turbulence and formation of air bubbles in the seepmeter water flow tubes. Salinity had no significant effect on the performance of the seepmeter. Calibration results from fresh water and sea water showed close agreement at a 95% confidence level significance between the data sets from the two media (R2 = 0.98). Comparatively, the seepmeter SGD measurements provided data that are comparable to manually-operated seepage meters, the radon geochemical tracer approach, and an electromagnetic (EM) seepage meter. ?? 2009 Elsevier Ltd.

  9. Pressure-Temperature Simulation at Brady Hot Springs

    DOE Data Explorer

    Feigl, Kurt (ORCID:0000000220596708)

    2017-07-11

    These files contain the output of a model calculation to simulate the pressure and temperature of fluid at Brady Hot Springs, Nevada, USA. The calculation couples the hydrologic flow (Darcy's Law) with simple thermodynamics. The epoch of validity is 24 March 2015. Coordinates are UTM Easting, Northing, and Elevation in meters. Temperature is specified in degrees Celsius. Pressure is specified in Pascal.

  10. Frequency response of portable PEF meters.

    PubMed

    Hankinson, J L; Das, M K

    1995-08-01

    Peak expiratory flow (PEF) is a dynamic parameter and therefore requires a measuring device with a high-frequency response. This study evaluated the frequency-response characteristics of eight commercially available PEF meters, using simulated forced-expiratory maneuvers with a computer-controlled mechanical pump. Three different PEF levels were used (200, 400, and 600 L/min) at six levels of harmonic-frequency content similar to those observed in human subjects. For waveforms with higher frequency content (at the high end or above the physiologic range), the Assess, Vitalograph, Pocket Peak, and Spir-O-Flow PEF meters all overread PEF (greater than 15% difference from target values) at all three PEF levels. These results suggest that the frequency response of PEF meters is an important consideration in the selection of such meters and should be included in device requirements. The current practice of using various levels of American Thoracic Society (ATS) waveform 24 with its low-frequency content may not adequately evaluate the frequency characteristics of PEF meters. An upper range (5% of the fundamental frequency) of 12 Hz, within the range observed in normal subjects, appears to be more practical than an upper limit of 20 Hz.

  11. Chevron facility focused on commercial orifice-meter research

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, E.H.; Ferguson, K.R.

    1987-07-27

    Research to determine the accuracy of commercial orifice meters for custody-transfer measurement has indicated that high-volume gas meters can be flow-proven while in such service. The research further yielded more accurate orifice-meter discharge coefficient equations (at Reynolds numbers greater than 4,000,000) than current equations of the International Standards Organization (ISO) and the American Petroleum Institute (API). These are partial findings of a major study conducted by Chevron Oil Field Research Co. at its Venice, La., calibration facility.

  12. 40 CFR 1065.325 - Intake-flow calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Section 1065.325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related Measurements § 1065.325 Intake-flow calibration. (a) Calibrate intake-air flow meters upon initial installation. Follow the...

  13. Sample preparation system for microfluidic applications

    DOEpatents

    Mosier, Bruce P [San Francisco, CA; Crocker, Robert W [Fremont, CA; Patel, Kamlesh D [Dublin, CA; Harnett, Cindy K [Livermore, CA

    2007-05-08

    An apparatus that couples automated injection with flow feedback to provide nanoliter accuracy in controlling microliter volumes. The apparatus comprises generally a source of hydraulic fluid pressure, a fluid isolator joined to the outlet of the hydraulic pressure source and a flow sensor to provide pressure-driven analyte metering. For operation generally and particularly in microfluidic systems the hydraulic pressure source is typically an electrokinetic (EK) pump that incorporates gasless electrodes. The apparatus is capable of metering sub-microliter volumes at flowrates of 1 100 .mu.L/min into microsystem load pressures of up to 1000 50 psi, respectively. Flowrates can be specified within 0.5 .mu.L/min and volumes as small as 80 nL can be metered.

  14. Effects of simulated ice on the performance of price type-AA current meter rotors

    USGS Publications Warehouse

    Fulford, Janice M.

    1994-01-01

    Slush ice readily adheres to the standard metal rotor of the winter Price type-AA current meter and affects the ability of the meter to measure the flow velocity accurately. Tests conducted at the U.S. Geological Survey Hydraulics Laboratory at Stennis Space Center, Mississippi, attempt to quantify the effects of slush ice on the performance of standard Price type-AA meter metal rotors. Test data obtained for rotors filled with simulated slush are compared with data for solid-cup polymer and standard hollow-cup metal rotors. Partial filling of the cups only marginally affects rotor performance at velocities greater than 15.24 centimeters per second. However, when cups are filled or over-filled with simulated slush, rotor performance is noticeably affected. Errors associated with slush over-filling and filling of cups are also significant when flows are angled vertically.

  15. Development and evaluation of virtual refrigerant mass flow sensors for fault detection and diagnostics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Woohyun; Braun, J.

    Refrigerant mass flow rate is an important measurement for monitoring equipment performance and enabling fault detection and diagnostics. However, a traditional mass flow meter is expensive to purchase and install. A virtual refrigerant mass flow sensor (VRMF) uses a mathematical model to estimate flow rate using low-cost measurements and can potentially be implemented at low cost. This study evaluates three VRMFs for estimating refrigerant mass flow rate. The first model uses a compressor map that relates refrigerant flow rate to measurements of inlet and outlet pressure, and inlet temperature measurements. The second model uses an energy-balance method on the compressormore » that uses a compressor map for power consumption, which is relatively independent of compressor faults that influence mass flow rate. The third model is developed using an empirical correlation for an electronic expansion valve (EEV) based on an orifice equation. The three VRMFs are shown to work well in estimating refrigerant mass flow rate for various systems under fault-free conditions with less than 5% RMS error. Each of the three mass flow rate estimates can be utilized to diagnose and track the following faults: 1) loss of compressor performance, 2) fouled condenser or evaporator filter, 3) faulty expansion device, respectively. For example, a compressor refrigerant flow map model only provides an accurate estimation when the compressor operates normally. When a compressor is not delivering the expected flow due to a leaky suction or discharge valve or other internal fault, the energy-balance or EEV model can provide accurate flow estimates. In this paper, the flow differences provide an indication of loss of compressor performance and can be used for fault detection and diagnostics.« less

  16. Recognition and measurement gas-liquid two-phase flow in a vertical concentric annulus at high pressures

    NASA Astrophysics Data System (ADS)

    Li, Hao; Sun, Baojiang; Guo, Yanli; Gao, Yonghai; Zhao, Xinxin

    2018-02-01

    The air-water flow characteristics under pressure in the range of 1-6 MPa in a vertical annulus were evaluated in this report. Time-resolved bubble rising velocity and void fraction were also measured using an electrical void fraction meter. The results showed that the pressure has remarkable effect on the density, bubble size and rise velocity of the gas. Four flow patterns (bubble, cap-bubble, cap-slug, and churn) were also observed instead of Taylor bubble at high pressure. Additionally, the transition process from bubble to cap-bubble was investigated at atmospheric and high pressures, respectively. The results revealed that the flow regime transition criteria for atmospheric pressure do not work at high pressure, hence a new flow regime transition model for annular flow channel geometry was developed to predict the flow regime transition, which thereafter exhibited high accuracy at high pressure condition.

  17. Understanding and predicting changing use of groundwater with climate and other uncertainties: a Bayesian approach

    NASA Astrophysics Data System (ADS)

    Costa, F. A. F.; Keir, G.; McIntyre, N.; Bulovic, N.

    2015-12-01

    Most groundwater supply bores in Australia do not have flow metering equipment and so regional groundwater abstraction rates are not well known. Past estimates of unmetered abstraction for regional numerical groundwater modelling typically have not attempted to quantify the uncertainty inherent in the estimation process in detail. In particular, the spatial properties of errors in the estimates are almost always neglected. Here, we apply Bayesian spatial models to estimate these abstractions at a regional scale, using the state-of-the-art computationally inexpensive approaches of integrated nested Laplace approximation (INLA) and stochastic partial differential equations (SPDE). We examine a case study in the Condamine Alluvium aquifer in southern Queensland, Australia; even in this comparatively data-rich area with extensive groundwater abstraction for agricultural irrigation, approximately 80% of bores do not have reliable metered flow records. Additionally, the metering data in this area are characterised by complicated statistical features, such as zero-valued observations, non-normality, and non-stationarity. While this precludes the use of many classical spatial estimation techniques, such as kriging, our model (using the R-INLA package) is able to accommodate these features. We use a joint model to predict both probability and magnitude of abstraction from bores in space and time, and examine the effect of a range of high-resolution gridded meteorological covariates upon the predictive ability of the model. Deviance Information Criterion (DIC) scores are used to assess a range of potential models, which reward good model fit while penalising excessive model complexity. We conclude that maximum air temperature (as a reasonably effective surrogate for evapotranspiration) is the most significant single predictor of abstraction rate; and that a significant spatial effect exists (represented by the SPDE approximation of a Gaussian random field with a Matérn covariance function). Our final model adopts air temperature, solar exposure, and normalized difference vegetation index (NDVI) as covariates, shows good agreement with previous estimates at a regional scale, and additionally offers rigorous quantification of uncertainty in the estimate.

  18. Lessons From the Largest Historic Floods Documented by the U.S. Geological Survey

    NASA Astrophysics Data System (ADS)

    Costa, J. E.

    2003-12-01

    A recent controversy over the flood risk downstream from a USGS streamgaging station in southern California that recorded a large debris flow led to the decision to closely examine a sample of the largest floods documented in the US. Twenty-nine floods that define the envelope curve of the largest rainfall-runoff floods were examined in detail, including field visits. These floods have a profound impact on local, regional, and national interpretations of potential peak discharges and flood risk. These 29 floods occured throughout the US from the northern Chesapeake Bay in Maryland to Kauai, Hawaii, and over time from 1935-1978. Methods used to compute peak discharges were slope-area (21/29), culvert computations (2/29), measurements lost or not available for study (2/29), bridge contraction, culvert flow, and flow over road (1/29), rating curve extension (1/29), current meter measurement (1/29), and rating curve and current meter measurement (1/29). While field methods and tools have improved significantly over the last 70 years (e.g. total stations, GPS, GIS, hydroacoustics, digital plotters and computer programs like SAC and CAP), the primary methods of hydraulic analysis for indirect measurements of outstanding floods has not changed: today flow is still assumed to be 1-D and gradually varied. Unsteady or multi-dimensional flow models are rarely if ever used to determine peak discharges. Problems identified in this sample of 29 floods include debris flows misidentified as water floods, small drainage areas determined from small-scale maps and mislocated sites, high-water marks set by transient hydraulic phenomena, possibility of disconnected flow surfaces, scour assumptions in sand channels, poor site selection, incorrect approach angle for road overflow, and missing or lost records. Each published flood magnitude was checked by applying modern computer models with original field data, or by re-calculating computations. Four of 29 floods in this sample were found to have errors resulting in a change of the peak discharge of more than 10%.

  19. AUTOMATED TECHNIQUE FOR FLOW MEASUREMENTS FROM MARIOTTE RESERVOIRS.

    USGS Publications Warehouse

    Constantz, Jim; Murphy, Fred

    1987-01-01

    The mariotte reservoir supplies water at a constant hydraulic pressure by self-regulation of its internal gas pressure. Automated outflow measurements from mariotte reservoirs are generally difficult because of the reservoir's self-regulation mechanism. This paper describes an automated flow meter specifically designed for use with mariotte reservoirs. The flow meter monitors changes in the mariotte reservoir's gas pressure during outflow to determine changes in the reservoir's water level. The flow measurement is performed by attaching a pressure transducer to the top of a mariotte reservoir and monitoring gas pressure changes during outflow with a programmable data logger. The advantages of the new automated flow measurement techniques include: (i) the ability to rapidly record a large range of fluxes without restricting outflow, and (ii) the ability to accurately average the pulsing flow, which commonly occurs during outflow from the mariotte reservoir.

  20. The Influence of Multi-Scale Stratal Architecture on Multi-Phase Flow

    NASA Astrophysics Data System (ADS)

    Soltanian, M.; Gershenzon, N. I.; Ritzi, R. W.; Dominic, D.; Ramanathan, R.

    2012-12-01

    Geological heterogeneity affects flow and transport in porous media, including the migration and entrapment patterns of oil, and efforts for enhanced oil recovery. Such effects are only understood through their relation to a hierarchy of reservoir heterogeneities over a range of scales. Recent work on modern rivers and ancient sediments has led to a conceptual model of the hierarchy of fluvial forms within channel-belts of gravelly braided rivers, and a quantitative model for the corresponding scales of heterogeneity within the stratal architecture (e.g. [Lunt et al (2004) Sedimentology, 51 (3), 377]). In related work, a three-dimensional digital model was developed which represents these scales of fluvial architecture, the associated spatial distribution of permeability, and the connectivity of high-permeability pathways across the different scales of the stratal hierarchy [Ramanathan et al, (2010) Water Resour. Res., 46, W04515; Guin et al, (2010) Water Resour. Res., 46, W04516]. In the present work we numerically examine three-phase fluid flow (water-oil-gas) incorporating the multi-scale model for reservoir heterogeneity spanning the scales from 10^-1 to 10^3 meters. Comparison with results of flow in a reservoir with homogeneous permeability is made showing essentially different flow dynamics.

  1. Lateral Variability of Lava flow Morphologies in the Deccan Traps Large Igneous Province (India)

    NASA Astrophysics Data System (ADS)

    Vanderkluysen, L.; Rader, E. L.; Self, S.; Clarke, A. B.; Sheth, H.; Moyer, D. K.

    2016-12-01

    In continental flood basalt provinces (CFBs), lava flow morphologies have traditionally been classified in two distinct groups recognizable in the field, expressing two different modes of lava flow emplacement mechanisms: (a) compound lava flow fields dominated by meter-sized pāhoehoe toes and lobes; and (b) inflated sheet lobes tens to hundreds of meters in width and meters to tens of meters in height. Temporal transitions between these two emplacement styles have been recognized in many mafic large igneous provinces worldwide and seem to be a fundamental feature of CFBs. However, lateral variations in these morphologies remain poorly studied and understood. In the Deccan CFB of India, two principal hypotheses have been proposed to account for possible lateral variations in lava flow facies: that smaller toes and lobes occur in distal regions of flow fields, representing breakouts at the edges of larger inflated lavas; or on the contrary that smaller toes and lobes represent proximal facies. We conducted a field study focusing on two of the Deccan's formations, the Khandala and the Poladpur, located in the middle and upper sections of the province's defined chemostratigraphy. We studied nine sections along a 600 km long E-W transect, with the easternmost sections representing the most distal outcrops, ≥ 500 km away from inferred vents. The Khandala Formation is traditionally described as a sequence of three thick inflated sheet lobes in the well-exposed sections of the western Deccan. However, in the central Deccan, we find the Khandala to be much thicker overall, with half of its thickness dominated by small, meter-sized toes and lobes. Inflated sheet lobes of the Khandala are thinner on average in the central Deccan than further to the east or west. We document this transition as occurring progressively in outcrops only 80 km apart. In the Poladpur, the average thickness of inflated sheet lobes increases in distal outcrops of the eastern Deccan. We interpret these results as an indication that smaller, meter-sized toes and lobes are indicative of proximal facies, whereas the thickest (> 10 m) inflated sheet lobes are the most likely to reach the far edges of the province. Analogue experiments are currently under way to test the relative importance of eruption parameters in the development of these morphologies.

  2. Particle Size Reduction in Geophysical Granular Flows: The Role of Rock Fragmentation

    NASA Astrophysics Data System (ADS)

    Bianchi, G.; Sklar, L. S.

    2016-12-01

    Particle size reduction in geophysical granular flows is caused by abrasion and fragmentation, and can affect transport dynamics by altering the particle size distribution. While the Sternberg equation is commonly used to predict the mean abrasion rate in the fluvial environment, and can also be applied to geophysical granular flows, predicting the evolution of the particle size distribution requires a better understanding the controls on the rate of fragmentation and the size distribution of resulting particle fragments. To address this knowledge gap we are using single-particle free-fall experiments to test for the influence of particle size, impact velocity, and rock properties on fragmentation and abrasion rates. Rock types tested include granodiorite, basalt, and serpentinite. Initial particle masses and drop heights range from 20 to 1000 grams and 0.1 to 3.0 meters respectively. Preliminary results of free-fall experiments suggest that the probability of fragmentation varies as a power function of kinetic energy on impact. The resulting size distributions of rock fragments can be collapsed by normalizing by initial particle mass, and can be fit with a generalized Pareto distribution. We apply the free-fall results to understand the evolution of granodiorite particle-size distributions in granular flow experiments using rotating drums ranging in diameter from 0.2 to 4.0 meters. In the drums, we find that the rates of silt production by abrasion and gravel production by fragmentation scale with drum size. To compare these rates with free-fall results we estimate the particle impact frequency and velocity. We then use population balance equations to model the evolution of particle size distributions due to the combined effects of abrasion and fragmentation. Finally, we use the free-fall and drum experimental results to model particle size evolution in Inyo Creek, a steep, debris-flow dominated catchment, and compare model results to field measurements.

  3. 40 CFR 1065.330 - Exhaust-flow calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Section 1065.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related Measurements § 1065.330... ultrasonic flow meter for raw exhaust flow measurement, we recommend that you calibrate it as described in...

  4. Techniques and equipment required for precise stream gaging in tide-affected fresh-water reaches of the Sacramento River, California

    USGS Publications Warehouse

    Smith, Winchell

    1971-01-01

    Current-meter measurements of high accuracy will be required for calibration of an acoustic flow-metering system proposed for installation in the Sacramento River at Chipps Island in California. This report presents an analysis of the problem of making continuous accurate current-meter measurements in this channel where the flow regime is changing constantly in response to tidal action. Gaging-system requirements are delineated, and a brief description is given of the several applicable techniques that have been developed by others. None of these techniques provides the accuracies required for the flowmeter calibration. A new system is described--one which has been assembled and tested in prototype and which will provide the matrix of data needed for accurate continuous current-meter measurements. Analysis of a large quantity of data on the velocity distribution in the channel of the Sacramento River at Chipps Island shows that adequate definition of the velocity can be made during the dominant flow periods--that is, at times other than slack-water periods--by use of current meters suspended at elevations 0.2 and 0.8 of the depth below the water surface. However, additional velocity surveys will be necessary to determine whether or not small systematic corrections need be applied during periods of rapidly changing flow. In the proposed system all gaged parameters, including velocities, depths, position in the stream, and related times, are monitored continuously as a boat moves across the river on the selected cross section. Data are recorded photographically and transferred later onto punchcards for computer processing. Computer programs have been written to permit computation of instantaneous discharges at any selected time interval throughout the period of the current meter measurement program. It is anticipated that current-meter traverses will be made at intervals of about one-half hour over periods of several days. Capability of performance for protracted periods was, consequently, one of the important elements in system design. Analysis of error sources in the proposed system indicates that errors in individual computed discharges can be kept smaller than 1.5 percent if the expected precision in all measured parameters is maintained.

  5. Hemolytic potential of hydrodynamic cavitation.

    PubMed

    Chambers, S D; Bartlett, R H; Ceccio, S L

    2000-08-01

    The purpose of this study was to determine the hemolytic potentials of discrete bubble cavitation and attached cavitation. To generate controlled cavitation events, a venturigeometry hydrodynamic device, called a Cavitation Susceptibility Meter (CSM), was constructed. A comparison between the hemolytic potential of discrete bubble cavitation and attached cavitation was investigated with a single-pass flow apparatus and a recirculating flow apparatus, both utilizing the CSM. An analytical model, based on spherical bubble dynamics, was developed for predicting the hemolysis caused by discrete bubble cavitation. Experimentally, discrete bubble cavitation did not correlate with a measurable increase in plasma-free hemoglobin (PFHb), as predicted by the analytical model. However, attached cavitation did result in significant PFHb generation. The rate of PFHb generation scaled inversely with the Cavitation number at a constant flow rate, suggesting that the size of the attached cavity was the dominant hemolytic factor.

  6. Hydrogeochemical zonation in intertidal salt marsh sediments: evidence of positive plant-soil feedback?

    NASA Astrophysics Data System (ADS)

    Moffett, K. B.; Dittmar, J.; Seyfferth, A.; Fendorf, S.; Gorelick, S.

    2012-12-01

    Surface and subsurface environments are linked by the biogeochemical activity in near-surface sediment and by the hydrological fluxes that mobilize its reagents and products. A particularly dynamic and interesting setting to study near-surface hydrogeochemistry is the intertidal zone. Here, the very strong tidal hydraulic forcing is often thought to dominate water and solute transport. However, we demonstrated the importance of two additional subsurface drivers: groundwater flow and plant root water uptake. A high-resolution, coupled surface water-groundwater model of an intertidal salt marsh in San Francisco Bay, CA showed that these three drivers vary over different spatial scales: tidal flooding varies over 10's of meters; groundwater flow varies over meters, particularly within channel banks; and plant root water uptake varies in 3D at the sub-meter scale. Expanding on this third driver, we investigated whether the spatial variations in soil-water-plant hydraulic interactions that occur due to vegetation zonation also cause distinct geochemical zonation in salt marsh sediment pore waters. The existence of such geochemical zonation was verified and mapped by detailed field observations of the chemical composition of sediments, pore waters, surface waters, and vegetation. The field data and the coupled hydrologic model were then further analyzed to evaluate potential causal mechanisms for the geochemical zonation, including testing the hypothesis that the vegetation affects pore water geochemistry via a positive feedback beneficial to itself. If further supported by future studies, this geochemical feedback may complement known physical ecosystem engineering mechanisms to help stabilize and organize intertidal wetlands.

  7. 1-Meter Digital Elevation Model specification

    USGS Publications Warehouse

    Arundel, Samantha T.; Archuleta, Christy-Ann M.; Phillips, Lori A.; Roche, Brittany L.; Constance, Eric W.

    2015-10-21

    In January 2015, the U.S. Geological Survey National Geospatial Technical Operations Center began producing the 1-Meter Digital Elevation Model data product. This new product was developed to provide high resolution bare-earth digital elevation models from light detection and ranging (lidar) elevation data and other elevation data collected over the conterminous United States (lower 48 States), Hawaii, and potentially Alaska and the U.S. territories. The 1-Meter Digital Elevation Model consists of hydroflattened, topographic bare-earth raster digital elevation models, with a 1-meter x 1-meter cell size, and is available in 10,000-meter x 10,000-meter square blocks with a 6-meter overlap. This report details the specifications required for the production of the 1-Meter Digital Elevation Model.

  8. Emergency assessment of post-fire debris-flow hazards for the 2013 Powerhouse fire, southern California

    USGS Publications Warehouse

    Staley, Dennis M.; Smoczyk, Gregory M.; Reeves, Ryan R.

    2013-01-01

    Wildfire dramatically alters the hydrologic response of a watershed such that even modest rainstorms can produce dangerous flash floods and debris flows. Existing empirical models were used to predict the probability and magnitude of debris-flow occurrence in response to a 10-year recurrence interval rainstorm for the 2013 Powerhouse fire near Lancaster, California. Overall, the models predict a relatively low probability for debris-flow occurrence in response to the design storm. However, volumetric predictions suggest that debris flows that occur may entrain a significant volume of material, with 44 of the 73 basins identified as having potential debris-flow volumes between 10,000 and 100,000 cubic meters. These results suggest that even though the likelihood of debris flow is relatively low, the consequences of post-fire debris-flow initiation within the burn area may be significant for downstream populations, infrastructure, and wildlife and water resources. Given these findings, we recommend that residents, emergency managers, and public works departments pay close attention to weather forecasts and National-Weather-Service-issued Debris Flow and Flash Flood Outlooks, Watches, and Warnings and that residents adhere to any evacuation orders.

  9. Evaluation of a turbine flow meter (Ventilometer Mark 2) in the measurement of ventilation.

    PubMed

    Cooper, C B; Harris, N D; Howard, P

    1990-01-01

    We have evaluated a turbine flow meter (Ventilometer Mark 2, PK Morgan, Kent, UK) at low flow rates and levels of ventilation which are likely to be encountered during exercise in patients with chronic respiratory disease. Pulsatile flows were generated from a volume-cycled mechanical ventilator, the flow wave-form was modified by damping to simulate a human breathing pattern. Comparative measurements of ventilation were made whilst varying tidal volume (VT) from 0.22 to 1.131 and respiratory rate (fR) from 10 to 35 min-1. At lower levels of ventilation the instrument tended to underread especially with increasing fR. The calibration factor must be adjusted to match the level of ventilation if the measurement errors are to be within 5%.

  10. Probability and volume of potential postwildfire debris flows in the 2012 Waldo Canyon Burn Area near Colorado Springs, Colorado

    USGS Publications Warehouse

    Verdin, Kristine L.; Dupree, Jean A.; Elliott, John G.

    2012-01-01

    This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 Waldo Canyon fire near Colorado Springs in El Paso County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and potential volume of debris flows along the drainage network of the burned area and to estimate the same for 22 selected drainage basins along U.S. Highway 24 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall, referred to as a 2-year storm (29 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall, referred to as a 10-year storm (42 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall, referred to as a 25-year storm (48 millimeters). Estimated debris-flow probabilities at the pour points of the the drainage basins of interest ranged from less than 1 to 54 percent in response to the 2-year storm; from less than 1 to 74 percent in response to the 10-year storm; and from less than 1 to 82 percent in response to the 25-year storm. Basins and drainage networks with the highest probabilities tended to be those on the southern and southeastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Nine of the 22 drainage basins of interest have greater than a 40-percent probability of producing a debris flow in response to the 10-year storm. Estimated debris-flow volumes for all rainfalls modeled range from a low of 1,500 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce substantial volumes of material. The predicted probabilities and some of the volumes predicted for the modeled storms indicate a potential for substantial debris-flow impacts on structures, reservoirs, roads, bridges, and culverts located both within and immediately downstream from the burned area. U.S. Highway 24, on the southern edge of the burn area, is also susceptible to impacts from debris flows.

  11. Determining the optimal approach to identifying individuals with chronic obstructive pulmonary disease: The DOC study.

    PubMed

    Ronaldson, Sarah J; Dyson, Lisa; Clark, Laura; Hewitt, Catherine E; Torgerson, David J; Cooper, Brendan G; Kearney, Matt; Laughey, William; Raghunath, Raghu; Steele, Lisa; Rhodes, Rebecca; Adamson, Joy

    2018-06-01

    Early identification of chronic obstructive pulmonary disease (COPD) results in patients receiving appropriate management for their condition at an earlier stage in their disease. The determining the optimal approach to identifying individuals with chronic obstructive pulmonary disease (DOC) study was a case-finding study to enhance early identification of COPD in primary care, which evaluated the diagnostic accuracy of a series of simple lung function tests and symptom-based case-finding questionnaires. Current smokers aged 35 or more were invited to undertake a series of case-finding tools, which comprised lung function tests (specifically, spirometry, microspirometry, peak flow meter, and WheezoMeter) and several case-finding questionnaires. The effectiveness of these tests, individually or in combination, to identify small airways obstruction was evaluated against the gold standard of spirometry, with the quality of spirometry tests assessed by independent overreaders. The study was conducted with general practices in the Yorkshire and Humberside area, in the UK. Six hundred eighty-one individuals met the inclusion criteria, with 444 participants completing their study appointments. A total of 216 (49%) with good-quality spirometry readings were included in the analysis. The most effective case-finding tools were found to be the peak flow meter alone, the peak flow meter plus WheezoMeter, and microspirometry alone. In addition to the main analysis, where the severity of airflow obstruction was based on fixed ratios and percent of predicted values, sensitivity analyses were conducted by using lower limit of normal values. This research informs the choice of test for COPD identification; case-finding by use of the peak flow meter or microspirometer could be used routinely in primary care for suspected COPD patients. Only those testing positive to these tests would move on to full spirometry, thereby reducing unnecessary spirometric testing. © 2018 John Wiley & Sons, Ltd.

  12. The Cardiovascular Function Profile and Physical Fitness in Overweight Subjects

    NASA Astrophysics Data System (ADS)

    Megawati, E. R.; Lubis, L. D.; Harahap, F. Y.

    2017-03-01

    Obesity in children and young adult is associated with cardiovascular risk in short term and long term. The aim of this study was to describe the profile of the cardiovascular functions parameters and physical fitness in overweight. This is an analytical observational study with cross sectional approach. The samples of this study were 85 randomly selected subjects aged 18 to 24 years with normoweight and body mass index <40. The parameters measures were body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), cardiovascular function parameters (resting pulse, blood pressure, and peak flow meter) and physical fitness parameters (VO2max dengan McArdle step test). The mean BMI was 24,53±4,929. The WC and WHR mean were 86,7±14,10 cms and 0,89±0,073 cm respectively. The mean of resting pulses were higher in normoweight subject (p=0,0209). The mean systole were lower in normoweight subject (p=0,0026). No differences VO2 max between groups (p=0,3888). The peak flow meter was higher in normoweight (p=0,0274). The result of this study indicate that heart rate, systole and peak flow meter are signifantly different between groups. The heart rate and the peak flow meter in the overweight subjects were lower meanwhile the systole blood pressure was higher compared to normoweight subjects.

  13. Anatomy Of The ‘LuSi’ Mud Eruption, East Java

    NASA Astrophysics Data System (ADS)

    Tingay, M. R.

    2009-12-01

    Early in the morning of the 29th of May 2006, hot mud started erupting from the ground in the densely populated Porong District of Sidoarjo, East Java. With initial flow rates of ~5000 cubic meters per day, the mud quickly inundated neighbouring villages. Over two years later and the ‘Lusi’ eruption has increased in strength, expelling over 90 million cubic meters of mud at an average rate of approximately 100000 cubic meters per day. The mud flow has now covered over 700 hectares of land to depths of over 25 meters, engulfing a dozen villages and displacing approximately 40000 people. In addition to the inundated areas, other areas are also at risk from subsidence and distant eruptions of gas. However, efforts to stem the mud flow or monitor its evolution are hampered by our overall lack of knowledge and consensus on the subsurface anatomy of the Lusi mud volcanic system. In particular, the largest and most significant uncertainties are the source of the erupted water (shales versus deep carbonates), the fluid flow pathways (purely fractures versus mixed fracture and wellbore) and disputes over the subsurface geology (nature of deep carbonates, lithology of rocks between shale and carbonates). This study will present and overview of the anatomy of the Lusi mud volcanic system with particular emphasis on these critical uncertainties and their influence on the likely evolution of disaster.

  14. Postwildfire preliminary debris flow hazard assessment for the area burned by the 2011 Las Conchas Fire in north-central New Mexico

    USGS Publications Warehouse

    Tillery, Anne C.; Darr, Michael J.; Cannon, Susan H.; Michael, John A.

    2011-01-01

    The Las Conchas Fire during the summer of 2011 was the largest in recorded history for the state of New Mexico, burning 634 square kilometers in the Jemez Mountains of north-central New Mexico. The burned landscape is now at risk of damage from postwildfire erosion, such as that caused by debris flows and flash floods. This report presents a preliminary hazard assessment of the debris-flow potential from 321 basins burned by the Las Conchas Fire. A pair of empirical hazard-assessment models developed using data from recently burned basins throughout the intermountain western United States was used to estimate the probability of debris-flow occurrence and volume of debris flows at the outlets of selected drainage basins within the burned area. The models incorporate measures of burn severity, topography, soils, and storm rainfall to estimate the probability and volume of debris flows following the fire. In response to a design storm of 28.0 millimeters of rain in 30 minutes (10-year recurrence interval), the probabilities of debris flows estimated for basins burned by the Las Conchas Fire were greater than 80 percent for two-thirds (67 percent) of the modeled basins. Basins with a high (greater than 80 percent) probability of debris-flow occurrence were concentrated in tributaries to Santa Clara and Rio del Oso Canyons in the northeastern part of the burned area; some steep areas in the Valles Caldera National Preserve, Los Alamos, and Guaje Canyons in the east-central part of the burned area; tributaries to Peralta, Colle, Bland, and Cochiti canyons in the southwestern part of the burned area; and tributaries to Frijoles, Alamo, and Capulin Canyons in the southeastern part of the burned area (within Bandelier National Monument). Estimated debris-flow volumes ranged from 400 cubic meters to greater than 72,000 cubic meters. The largest volumes (greater than 40,000 cubic meters) were estimated for basins in Santa Clara, Los Alamos, and Water Canyons, and for two basins at the northeast edge of the burned area tributary to Rio del Oso and Vallecitos Creek. The Combined Relative Debris-Flow Hazard Rankings identify the areas of highest probability of the largest debris flows. Basins with high Combined Relative Debris-Flow Hazard Rankings include upper Santa Clara Canyon in the northern section of the burn scar, and portions of Peralta, Colle, Bland, Cochiti, Capulin, Alamo, and Frijoles Canyons in the southern section of the burn scar. Three basins with high Combined Relative Debris-Flow Hazard Rankings also occur in areas upstream from the city of Los Alamos—the city is home to and surrounded by numerous technical sites for the Los Alamos National Laboratory. Potential debris flows in the burned area could affect the water supply for Santa Clara Pueblo and several recreational lakes, as well as recreational and archeological resources in Bandelier National Monument. Debris flows could damage bridges and culverts along State Highway 501 and other roadways. Additional assessment is necessary to determine if the estimated volume of material is sufficient to travel into areas downstream from the modeled basins along the valley floors, where they could affect human life, property, agriculture, and infrastructure in those areas. Additionally, further investigation is needed to assess the potential for debris flows to affect structures at or downstream from basin outlets and to increase the threat of flooding downstream by damaging or blocking flood mitigation structures. The maps presented here may be used to prioritize areas where erosion mitigation or other protective measures may be necessary within a 2- to 3-year window of vulnerability following the Las Conchas Fire.

  15. Generalized additive regression models of discharge and mean velocity associated with direct-runoff conditions in Texas: Utility of the U.S. Geological Survey discharge measurement database

    USGS Publications Warehouse

    Asquith, William H.; Herrmann, George R.; Cleveland, Theodore G.

    2013-01-01

    A database containing more than 17,700 discharge values and ancillary hydraulic properties was assembled from summaries of discharge measurement records for 424 U.S. Geological Survey streamflow-gauging stations (stream gauges) in Texas. Each discharge exceeds the 90th-percentile daily mean streamflow as determined by period-of-record, stream-gauge-specific, flow-duration curves. Each discharge therefore is assumed to represent discharge measurement made during direct-runoff conditions. The hydraulic properties of each discharge measurement included concomitant cross-sectional flow area, water-surface top width, and reported mean velocity. Systematic and statewide investigation of these data in pursuit of regional models for the estimation of discharge and mean velocity has not been previously attempted. Generalized additive regression modeling is used to develop readily implemented procedures by end-users for estimation of discharge and mean velocity from select predictor variables at ungauged stream locations. The discharge model uses predictor variables of cross-sectional flow area, top width, stream location, mean annual precipitation, and a generalized terrain and climate index (OmegaEM) derived for a previous flood-frequency regionalization study. The mean velocity model uses predictor variables of discharge, top width, stream location, mean annual precipitation, and OmegaEM. The discharge model has an adjusted R-squared value of about 0.95 and a residual standard error (RSE) of about 0.22 base-10 logarithm (cubic meters per second); the mean velocity model has an adjusted R-squared value of about 0.67 and an RSE of about 0.063 fifth root (meters per second). Example applications and computations using both regression models are provided. - See more at: http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29HE.1943-5584.0000635#sthash.jhGyPxgZ.dpuf

  16. Evaluation of the turbine pocket spirometer.

    PubMed Central

    Gunawardena, K A; Houston, K; Smith, A P

    1987-01-01

    A compact electronic spirometer, the turbine pocket spirometer, which measures the FEV1, forced vital capacity (FVC), and peak expiratory flow (PEF) in a single expiration, was compared with the Vitalograph and the Wright peak flow meter in 99 subjects (FEV1 range 0.40-5.50 litres; FVC 0.58-6.48 l; PEF 40-650 l min-1). The mean differences between the machines were small--0.05 l for FEV1, 0.05 l for FVC, and 11.6 l min-1 for PEF, with the limits of agreement at +/- 0.25 l, +/- 0.48 l, and +/- 52.2 l min-1 respectively. The wide limits of agreement for the PEF comparison were probably because of the difference in the technique of blowing: a fast, long blow was used for the pocket spirometer and a short, sharp one for the Wright peak flow meter. The FEV1 and FVC showed a proportional bias of around 4-5% in favour of the Vitalograph. The repeatability coefficient for the pocket spirometer FEV1 was 0.18 l, for FVC 0.22 l, and for PEF 31 l min-1. These compared well with the repeatability coefficients of the Vitalograph and the Wright peak flow meter, which gave values of 0.18 l, 0.28 l, and 27 l min-1 respectively. At flow rates of over 600 l min-1 the resistance of the pocket spirometer marginally exceeded the American Thoracic Society recommendations. The machine is easy to operate and portable, and less expensive than the Vitalograph and Wright peak flow meter combined. It can be recommended for general use. Images PMID:3686460

  17. Measurement of lung volume in mechanically ventilated monkeys with an ultrasonic flow meter and the nitrogen washout method.

    PubMed

    Schibler, Andreas; Hammer, Jürg; Isler, Ruedi; Buess, Christian; Newth, Christopher J L

    2004-01-01

    Measurement of functional residual capacity (FRC) during mechanical ventilation is important to standardise respiratory system compliance and adjust the ventilator settings to optimise lung recruitment. In the present study we compared three methods to measure FRC. The bias flow nitrogen washout technique (FRC(N2MC)), the multiple breath nitrogen washout (FRC(MBNW)) and the multiple breath sulphur-hexafluoride washout using the molar mass signal of an ultrasonic flow meter (FRC(MBSF6)) were compared in six adult monkeys after endotracheal intubation and during spontaneous breathing and mechanical ventilation at three different positive end-expiratory pressure (PEEP) levels of 0, 5 and 10 cmH2O. Animal research laboratory. We found good agreement between all three methods and they all accurately measured changes in FRC when PEEP was increased. The coefficients of variance of the three measurement techniques were in the same range (1.3-9.2%). The measurement of the tracer gas concentration with the molar mass signal of the ultrasonic flow meter provides a good and simple alternative to respiratory mass spectrometer for FRC measurements in ventilated subjects.

  18. Model Performance of Water-Current Meters

    USGS Publications Warehouse

    Fulford, J.M.; ,

    2002-01-01

    The measurement of discharge in natural streams requires hydrographers to use accurate water-current meters that have consistent performance among meters of the same model. This paper presents the results of an investigation into the performance of four models of current meters - Price type-AA, Price pygmy, Marsh McBirney 2000 and Swoffer 2100. Tests for consistency and accuracy for six meters of each model are summarized. Variation of meter performance within a model is used as an indicator of consistency, and percent velocity error that is computed from a measured reference velocity is used as an indicator of meter accuracy. Velocities measured by each meter are also compared to the manufacturer's published or advertised accuracy limits. For the meters tested, the Price models werer found to be more accurate and consistent over the range of test velocities compared to the other models. The Marsh McBirney model usually measured within its accuracy specification. The Swoffer meters did not meet the stringent Swoffer accuracy limits for all the velocities tested.

  19. 40 CFR 1065.340 - Diluted exhaust flow (CVS) calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... initial CVS installation and whenever corrective action does not resolve a failure to meet the diluted... such as a subsonic venturi flow meter, a long-radius ASME/NIST flow nozzle, a smooth approach orifice...

  20. 40 CFR 1065.340 - Diluted exhaust flow (CVS) calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... initial CVS installation and whenever corrective action does not resolve a failure to meet the diluted... such as a subsonic venturi flow meter, a long-radius ASME/NIST flow nozzle, a smooth approach orifice...

  1. 40 CFR 1065.340 - Diluted exhaust flow (CVS) calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... initial CVS installation and whenever corrective action does not resolve a failure to meet the diluted... such as a subsonic venturi flow meter, a long-radius ASME/NIST flow nozzle, a smooth approach orifice...

  2. Integrating flood modelling in a hydrological catchment model: flow approximations and spatial resolution.

    NASA Astrophysics Data System (ADS)

    van den Bout, Bastian; Jetten, Victor

    2017-04-01

    Within hydrological models, flow approximations are commonly used to reduce computation time. The validity of these approximations is strongly determined by flow height, flow velocity, the spatial resolution of the model, and by the manner in which flow routing is implemented. The assumptions of these approximations can furthermore limit emergent behavior, and influence flow behavior under space-time scaling. In this presentation, the validity and performance of the kinematic, diffusive and dynamic flow approximations are investigated for use in a catchment-based flood model. Particularly, the validity during flood events and for varying spatial resolutions is investigated. The OpenLISEM hydrological model is extended to implement these flow approximations and channel flooding based on dynamic flow. The kinematic routing uses a predefined converging flow network, the diffusive and dynamic routing uses a 2D flow solution over a DEM. The channel flow in all cases is a 1D kinematic wave approximation. The flow approximations are used to recreate measured discharge in three catchments of different size in China, Spain and Italy, among which is the hydrograph of the 2003 flood event in the Fella river basin (Italy). Furthermore, spatial resolutions are varied for the flood simulation in order to investigate the influence of spatial resolution on these flow approximations. Results show that the kinematic, diffusive and dynamic flow approximation provide least to highest accuracy, respectively, in recreating measured temporal variation of the discharge. Kinematic flow, which is commonly used in hydrological modelling, substantially over-estimates hydrological connectivity in the simulations with a spatial resolution of below 30 meters. Since spatial resolutions of models have strongly increased over the past decades, usage of routed kinematic flow should be reconsidered. In the case of flood events, spatial modelling of kinematic flow substantially over-estimates hydrological connectivity and flow concentration, leading to significant errors. The combination of diffusive or dynamic overland flow and dynamic channel flooding provides high accuracy in recreating the 2003 Fella river flood event. Finally, flow approximations substantially influenced the predictive potential of the (flash) flood model.

  3. Perturbations of the magnetic induction in a bubbly liquid metal flow

    NASA Astrophysics Data System (ADS)

    Guichou, Rafael; Tordjeman, Philippe; Bergez, Wladimir; Zamansky, Remi; Paumel, Kevin

    2017-11-01

    The presence of bubbles in liquid metal flow subject to AC magnetic field modifies the distribution of eddy currents in the fluid. This situation is encountered in metallurgy and nuclear industry for Sodium Fast Reactors. We will show that the perturbation of the eddy currents can be measured by an Eddy Current Flowmeter coupled with a lock-in amplifier. The experiments point out that the demodulated signal allows to detect the presence of a single bubble in the flow. The signal is sensitive both to the diameter and the relative position of the bubble. Then, we will present a model of a potential perturbation of the current density caused by a bubble and the distortion of the magnetic field. The eddy current distribution is calculated from the induction equation. This model is derived from a potential flow around a spherical particle. The total vector potential is the sum of the vector potential in the liquid metal flow without bubbles and the perturbated vector potential due to the presence of a bubble. The model is then compared to the experimental measurements realized with the eddy current flow meter for various bubble diameters in galinstan. The very good agreement between model and experiments validates the relevance of the perturbative approach.

  4. Quantifying hyporheic exchange dynamics in a highly regulated large river reach

    NASA Astrophysics Data System (ADS)

    Zhou, T.; Bao, J.; Huang, M.; Hou, Z.; Arntzen, E.; Mackley, R.; Harding, S.; Crump, A.; Xu, Y.; Song, X.; Chen, X.; Stegen, J.; Hammond, G. E.; Thorne, P. D.; Zachara, J. M.

    2016-12-01

    Hyporheic exchange is an important mechanism taking place in riverbanks and riverbed sediments, where the river water and shallow groundwater mix and interact with each other. The direction and magnitude of hyporheic flux that penetrates the river bed and residence time of river water in the hyporheic zone are critical for biogeochemical processes such as carbon and nitrogen cycling, and biodegradation of organic contaminants. Hyporheic flux can be quantified using many direct and indirect measurements as well as analytical and numerical modeling tools. However, in a relatively large river, these methods can be limited by the accessibility, spatial constraints, complexity of geomorphologic features and subsurface properties, and computational power. In rivers regulated by hydroelectric dams, quantifying hyporheic fluxes becomes more challenging due to frequent hydropeaking events created by dam operations. In this study, we developed and validated methods that combined field measurements and numerical modeling for estimating hyporheic fluxes across the river bed in a 7-km long reach of the highly regulated Columbia River. The reach has a minimum width of about 800 meters and variations in river stage within a day could be up to two meters due to the upstream dam operations. In shallow water along the shoreline, vertical thermal profiles measured by self-recording thermistors were combined with time series of hydraulic gradient derived from river stage and water level at in-land wells to estimate the hyporheic flux rate. For the deep section, a high resolution computational fluid dynamics (CFD) modeling framework was developed to characterize the spatial distribution of flux rates at the river bed and the residence time of hyporheic flow at different river flow conditions. Our modeling results show that the rates of hyporheic exchange and residence time are controlled by (1) hydrostatic pressure induced by river stage fluctuations, and (2) hydrodynamic drivers associated with flow velocity variations, which also to certain extent dependent on flow conditions.

  5. Modeling Raw Sewage Leakage and Transport in the Unsaturated Zone of Carbonate Aquifer Using Carbamazepine as an Indicator

    NASA Astrophysics Data System (ADS)

    Yakirevich, A.; Kuznetsov, M.; Livshitz, Y.; Gasser, G.; Pankratov, I.; Lev, O.; Adar, E.; Dvory, N. Z.

    2016-12-01

    Fast contamination of groundwater in karstic aquifers can be caused due to leaky sewers, for example, or overflow from sewer networks. When flowing through a karst system, wastewater has the potential to reach the aquifer in a relatively short time. The Western Mountain Aquifer (Yarkon-Taninim) of Israel is one of the country's major water resources. During late winter 2013, maintenance actions were performed on a central sewage pipe that caused raw sewage to leak into the creek located in the study area. The subsequent infiltration of sewage through the thick ( 100 m) fractured/karst unsaturated zone led to a sharp increase in contaminant concentrations in the groundwater, which was monitored in a well located 29 meters from the center of the creek. Carbamazepine (CBZ) was used as an indicator for the presence of untreated raw sewage and its quantification in groundwater. The ultimate research goal was to develop a mathematical model for quantifying flow and contaminant transport processes in the fractured-porous unsaturated zone and karstified groundwater system. A quasi-3D dual permeability numerical model, representing the 'vadose zone - aquifer' system, was developed by a series of 1D equations solved in variably-saturated zone and by 3D-saturated flow and transport equation in groundwater. The 1D and 3D equations were coupled at the moving phreatic surface. The model was calibrated and applied to a simulated water flow scenario and CBZ transport during and after the observed sewage leakage event. The results of simulation showed that after the leakage stopped, significant amounts of CBZ were retained in the porous matrix of the unsaturated zone below the creek. Water redistribution and slow recharge during the dry summer season contributed to elevated CBZ concentrations in the groundwater in the vicinity of the creek and tens of meters downstream. The resumption of autumn rains enhanced flushing of CBZ from the unsaturated zone and led to an increase in groundwater concentrations.

  6. Water velocity meter

    NASA Technical Reports Server (NTRS)

    Roberts, C. W.; Smith, D. L.

    1970-01-01

    Simple, inexpensive drag sphere velocity meter with a zero to 6 ft/sec range measures steady-state flow. When combined with appropriate data acquisition system, it is suited to applications where large numbers of simultaneous measurements are needed for current mapping or velocity profile determination.

  7. Basic processes and factors determining the evolution of collapse sinkholes: a sensitivity study

    NASA Astrophysics Data System (ADS)

    Romanov, Douchko; Kaufmann, Georg

    2017-04-01

    Collapse sinkholes appear as closed depressions at the surface. The origin of these karst features is related to the continuous dissolution of the soluble rock caused by a focussed sub-surface flow. Water flowing along a preferential pathway through fissures and fractures within the phreatic part of a karst aquifer is able to dissolve the rock (limestone, gypsum, anhydrite). With time, the dissolved void volume increases and part of the ceiling above the stream can become unstable, collapses, and accumulates as debris in the flow path. The debris partially blocks the flow and thus activates new pathways. Because of the low compaction of the debris (high hydraulic conductivity), the flow and the dissolution rates within this crushed zone remain high. This allows a relatively fast dissolutional and erosional removal of the crushed material and the development of new empty voids. The void volume expands upwards towards the surface until a collapse sinkhole is formed. The collapse sinkholes exhibit a large variety of shapes (cylindrical, cone-, bowl-shaped), depths (from few to few hundred meters) and diameters (meters up to hundreds of meters). Two major processes are responsible for this diversity: a) the karst evolution of the aquifer - responsible for the dissolutional and erosional removal of material; b) the mechanical evolution of the host rock and the existence of structural features, faults for example, which determine the stability and the magnitude of the subsequent collapses. In this work we demonstrate the influence of the host rock type, the hydrological and geological boundary conditions, the chemical composition of the flowing water, and the geometry and the scale of the crushed zone, on the location and the evolution of the growing sinkhole. We demonstrate the ability of the karst evolution models to explain, at least qualitatively, the growth and the morphology of the collapse sinkholes and to roughly predict their shape and location. Implementing simple rules that describe the mechanical collapse, we come to the conclusion that a complete quantitative and qualitative description of a collapse sinkhole is possible, but for this it is necessary to take into account also the mechanical properties of the rock and the processes determining the mechanics of the collapses.

  8. ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT FOR THE UV DISINFECTION OF SECONDARY EFFLUENTS, SUNTEC, INC. MODEL LPX200 DISINFECTION SYSTEM - 03/09/WQPC-SWP

    EPA Science Inventory

    Verification testing of the SUNTEC LPX200 UV Disinfection System to develop the UV delivered dose flow relationship was conducted at the Parsippany-Troy Hills wastewater treatment plant test site in Parsippany, New Jersey. Two lamp modules were mounted parallel in a 6.5-meter lon...

  9. Fan noise reduction achieved by removing tip flow irregularities behind the rotor - forward arc test configurations

    NASA Technical Reports Server (NTRS)

    Dittmar, J. H.; Woodward, R. P.; Mackinnon, M. J.

    1984-01-01

    The noise source caused by the interaction of the rotor tip flow irregularities (vortices and velocity defects) with the downstream stator vanes was studied. Fan flow was removed behind a 0.508 meter (20 in.) diameter model turbofan through an outer wall slot between the rotor and stator. Noise measurements were made with far-field microphones positioned in an arc about the fan inlet and with a pressure transducer in the duct behind the stator. Little tone noise reduction was observed in the forward arc during flow removal; possibly because the rotor-stator interaction noise did not propagate upstream through the rotor. Noise reductions were maded in the duct behind the stator and the largest decrease occurred with the first increment of flow removal. This result indicates that the rotor tip flow irregularity-stator interaction is as important a noise producing mechanism as the normally considered rotor wake-stator interaction.

  10. Experimental study on hydraulic characteristic around trash rack of a pumping station

    NASA Astrophysics Data System (ADS)

    Zhou, MinZhe; Li, TongChun; Lin, XiangYang; Liu, XiaoQing; Ding, Yuan; Liu, GuangYuan

    2017-11-01

    This paper focuses on flow pattern around trash rack of intake of a pumping station project. This pumping station undertake the task of supplying up to 3,500,000 m3 water per day for a megacity. Considering the large flow rate, high lift, multi-pipe supply and long-time operation in this water conveyance pumping station, we built a physical model test to measure the flow velocity and observe the flow pattern to verify the reasonability of preliminary design. In this test, we set 3 layers of current meters around each trash rack of intake in reservoir to collect the flow velocity. Furthermore, we design 2 operating conditions of 9 pumps to observe the change of flow pattern. Finally, we found the velocity data were in a normal range under 2 different operating conditions of the 9 pump units.

  11. Emergency assessment of post-fire debris-flow hazards for the 2013 Mountain fire, southern California

    USGS Publications Warehouse

    Staley, Dennis M.; Gartner, Joseph E.; Smoczyk, Greg M.; Reeves, Ryan R.

    2013-01-01

    Wildfire dramatically alters the hydrologic response of a watershed such that even modest rainstorms can produce dangerous flash floods and debris flows. We use empirical models to predict the probability and magnitude of debris flow occurrence in response to a 10-year rainstorm for the 2013 Mountain fire near Palm Springs, California. Overall, the models predict a relatively high probability (60–100 percent) of debris flow for six of the drainage basins in the burn area in response to a 10-year recurrence interval design storm. Volumetric predictions suggest that debris flows that occur may entrain a significant volume of material, with 8 of the 14 basins identified as having potential debris-flow volumes greater than 100,000 cubic meters. These results suggest there is a high likelihood of significant debris-flow hazard within and downstream of the burn area for nearby populations, infrastructure, and wildlife and water resources. Given these findings, we recommend that residents, emergency managers, and public works departments pay close attention to weather forecasts and National Weather Service–issued Debris Flow and Flash Flood Outlooks, Watches and Warnings and that residents adhere to any evacuation orders.

  12. Hydrokinetic canal measurements: inflow velocity, wake flow velocity, and turbulence

    DOE Data Explorer

    Gunawan, Budi

    2014-06-11

    The dataset consist of acoustic Doppler current profiler (ADCP) velocity measurements in the wake of a 3-meter diameter vertical-axis hydrokinetic turbine deployed in Roza Canal, Yakima, WA, USA. A normalized hub-centerline wake velocity profile and two cross-section velocity contours, 10 meters and 20 meters downstream of the turbine, are presented. Mean velocities and turbulence data, measured using acoustic Doppler velocimeter (ADV) at 50 meters upstream of the turbine, are also presented. Canal dimensions and hydraulic properties, and turbine-related information are also included.

  13. Modelling and optimization of a wellhead gas flowmeter using concentric pipes

    NASA Astrophysics Data System (ADS)

    Nec, Yana; Huculak, Greg

    2017-09-01

    A novel configuration of a landfill wellhead was analysed to measure the flow rate of gas extracted from sanitary landfills. The device provides access points for pressure measurement integral to flow rate computation similarly to orifice and Venturi meters, and has the advantage of eliminating the problem of water condensation often impairing the accuracy thereof. It is proved that the proposed configuration entails comparable computational complexity and negligible sensitivity to geometric parameters. Calibration for the new device was attained using a custom optimization procedure, operating on a quadri-dimensional parameter surface evincing discontinuity and non-smoothness.

  14. A system for calibrating seepage meters used to measure flow between ground water and surface water

    USGS Publications Warehouse

    Rosenberry, Donald O.; Menheer, Michael A.

    2006-01-01

    The in-line flowmeter used with this system is incapable of measuring seepage rates below about 7 centimeters per day. Smaller seepage rates can be measured manually. The seepage- control system also can be modified for measuring slower seepage rates with the use of two flowmeters and a slightly different water-routing system, or a fluid-metering pump can be used to control flow through the flux tank instead of an adjustable-height reservoir.

  15. Apparatus and method to inject a reductant into an exhaust gas feedstream

    DOEpatents

    Viola, Michael B [Macomb Township, MI

    2009-09-22

    An exhaust aftertreatment system for an internal combustion engine is provided including an apparatus and method to inject a reductant into the exhaust gas feedstream. Included is a fuel metering device adapted to inject reductant into the exhaust gas feedstream and a controllable pressure regulating device. A control module is operatively connected to the reductant metering device and the controllable pressure regulating device, and, adapted to effect flow of reductant into the exhaust gas feedstream over a controllable flow range.

  16. Research yields precise uncertainty equations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, E.H.; Ferguson, K.R.

    1987-08-03

    Results of a study of orifice-meter accuracy by Chevron Oil Field Research Co. at its Venice, La., calibration facility have important implications for natural gas custody-transfer measurement. The calibration facility, data collection, and equipment calibration were described elsewhere. This article explains the derivation of uncertainty factors and details the study's findings. The results were based on calibration of two 16-in. orifice-meter runs. The experimental data cover a beta-ratio range of from 0.27 to 0.71 and a Reynolds number range of from 4,000,000 to 35,000,000. Discharge coefficients were determined by comparing the orifice flow to the flow from critical-flow nozzles.

  17. Biological and associated water-quality data for lower Olmos Creek and upper San Antonio River, San Antonio, Texas, March-October 1990

    USGS Publications Warehouse

    Taylor, R. Lynn

    1995-01-01

    Depths and velocities, measured at sample points after benthic macroinvertebrate sampling, ranged from 0.03 to 0.30 meter and from 0.06 to 1.2 meters per second, respectively. Measurable stream discharge ranged from 0.01 to 0.27 cubic meter per second. During two of the sampling periods, no flow was at site 1.

  18. 40 CFR 1065.545 - Validation of proportional flow control for batch sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of the estimate, SEE, of the sample flow rate versus the total flow rate. For each test interval, demonstrate that SEE was less than or equal to 3.5% of the mean sample flow rate. (b) For any pair of flow meters, use recorded sample and total flow rates, where total flow rate means the raw exhaust flow rate...

  19. Basal terraces on melting ice shelves

    NASA Astrophysics Data System (ADS)

    Dutrieux, Pierre; Stewart, Craig; Jenkins, Adrian; Nicholls, Keith W.; Corr, Hugh F. J.; Rignot, Eric; Steffen, Konrad

    2014-08-01

    Ocean waters melt the margins of Antarctic and Greenland glaciers, and individual glaciers' responses and the integrity of their ice shelves are expected to depend on the spatial distribution of melt. The bases of the ice shelves associated with Pine Island Glacier (West Antarctica) and Petermann Glacier (Greenland) have similar geometries, including kilometer-wide, hundreds-of-meter high channels oriented along and across the direction of ice flow. The channels are enhanced by, and constrain, oceanic melt. New meter-scale observations of basal topography reveal peculiar glaciated landscapes. Channel flanks are not smooth, but are instead stepped, with hundreds-of-meters-wide flat terraces separated by 5-50 m high walls. Melting is shown to be modulated by the geometry: constant across each terrace, changing from one terrace to the next, and greatly enhanced on the ~45° inclined walls. Melting is therefore fundamentally heterogeneous and likely associated with stratification in the ice-ocean boundary layer, challenging current models of ice shelf-ocean interactions.

  20. Characterization of the Triassic Newark Basin of New York and New Jersey for geologic storage of carbon dioxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Collins, Daniel J.

    The Newark Basin is a Triassic-aged rift basin underlying densely populated, industrialized sections of New York, New Jersey and Pennsylvania. The Basin is an elongate half-graben encompassing an area of more than 7,510 square-kilometers (2,900 square-miles), and could represent a key storage component for commercial scale management of carbon dioxide emissions via geologic sequestration. The project team first acquired published reports, surface and subsurface maps, and seismic data, which formed the basis for a three-dimensional model framework for the northern end of the Basin incorporating stratigraphic, hydrologic, and water quality data. Field investigations included drilling, coring, and logging of two stratigraphic test borings in Clarkstown, NY (Exit 14 Tandem Lot Well No. 1), drilled to a depth of 2,099 meters (6,885 feet); and Palisades, NY (Lamont-Doherty Earth Observatory Test Well No. 4) drilled to a depth of 549 meters (1,802 feet). Two two-dimensional seismic reflection data lines arrayed perpendicularly were acquired by Schlumberger/WesternGeco to help characterize the structure and stratigraphy and as part of pre-drilling field screening activities for the deep stratigraphic borehole. A total of 47 meters (155 feet) of continuous whole core was recovered from the Tandem Lot boring from depths of 1,393 meters (4,570 feet) to 1,486 meters (4,877 feet). Twenty-five horizontal rotary cores were collected in mudstones and sandstones in the surface casing hole and fifty-two cores were taken in various lithologies in the deep borehole. Rotary core plugs were analyzed by Weatherford Laboratories for routine and advanced testing. Rotary core plug trim end thin sections were evaluated by the New York State Museum for mineralogical analysis and porosity estimation. Using core samples, Lawrence Berkley National Laboratory designed and completed laboratory experiments and numerical modeling analyses to characterize the dissolution and reaction of carbon dioxide with formation brine and minerals, and resulting effects on injection rate, pressure, effective storage volume, and carbon dioxide migration within a prospective sandstone reservoir.more » $$Three potential porous and permeable sandstone units were identified in the Passaic Formation at the New York State Thruway Exit 14 location. Potential Flow Unit 1, at a depth of 643 meters (2,110 feet) to 751 meters (2,465 feet); Potential Flow Unit 2 at a depth of 853 meters (2,798 feet) to 1,000 meters (3,280 feet); and Potential Flow Unit 3, at a depth of 1,114 meters (3,655 feet) to 1,294 meters (4,250 feet). Reactive transport simulations of interactions between carbon dioxide, brine and formation minerals were carried out to evaluate changes in formation water chemistry, mineral precipitation and dissolution reactions, and any potential resulting effects on formation permeability. The experimental and modeling analyses suggest that mineral precipitation and dissolution reactions (within the target formation) are not expected to lead to significant changes to the underground hydrologic system over time frames (~30 years) typically relevant for carbon dioxide injection operations. Key findings of this basin characterization study include an estimate of carbon dioxide storage capacity in the Newark Basin. Assuming an average porosity of twelve percent and an aquifer volume of 6.1E+12 meters3, calculated ranges of likely storage capacity range from 1.9 – 20.2 gigatonnes under high temperature (low carbon dioxide density) conditions; and 2.9 – 30.2 gigatonnes under low temperature (low carbon dioxide density) conditions. Intra-basin faulting, geometry of the Palisades Sill, and the presence of altered meta-sediments above and below the Sill, increase potential compartmentalization within the basin. A structural/stratigraphic trap type may occur where porous/permeable sediments are cross-cut by the Palisades Sill. Potential injection intervals are present within the Stockton Formation of the Newark Basin. Additional porous/permeable intervals may be present within sandstones of the Passaic Formation, increasing projected storage capacity. Deeper wedges of strata are likely present in the deeper portions of the basin in southern New York and into northern New Jersey. Abundant mudstones are present in the Passaic, Lockatong, and Stockton Formations. These intervals have the requisite petrophysical properties to form effective primary and secondary containment intervals to industrial-scale sequestration of carbon dioxide in the Newark Basin. Hydro-thermally altered meta-sediments in the region immediately surrounding the top and base of the Palisades Sill is devoid of porosity/permeability and forms an additional effective lateral/vertical sealing cap rock.« less

  1. Modeling and control study of the NASA 0.3-meter transonic cryogenic tunnel for use with sulfur hexafluoride medium

    NASA Technical Reports Server (NTRS)

    Balakrishna, S.; Kilgore, W. Allen

    1992-01-01

    The NASA Langley 0.3-m Transonic Cryogenic Tunnel is to be modified to operate with sulfur hexafluoride gas while retaining its present capability to operate with nitrogen. The modified tunnel will provide high Reynolds number flow on aerodynamic models with two different test gases. The document details a study of the SF6 tunnel performance boundaries, thermodynamic modeling of the tunnel process, nonlinear dynamical simulation of math model to yield tunnel responses, the closed loop control requirements, control laws, and mechanization of the control laws on the microprocessor based controller.

  2. Two Primary Standards for Low Flows of Gases

    PubMed Central

    Berg, Robert F.; Tison, Stuart A.

    2004-01-01

    We describe two primary standards for gas flow in the range from 0.1 to 1000 μmol/s. (1 μmol/s ≅ 1.3 cm3/min at 0 °C and 1 atmosphere.) The first standard is a volumetric technique in which measurements of pressure, volume, temperature, and time are recorded while gas flows in or out of a stainless steel bellows at constant pressure. The second standard is a gravimetric technique. A small aluminum pressure cylinder supplies gas to a laminar flow meter, and the integrated throughput of the laminar flow meter is compared to the weight decrease of the cylinder. The two standards, which have standard uncertainties of 0.019 %, agree to within combined uncertainties with each other and with a third primary standard at NIST based on pressure measurements at constant volume. PMID:27366623

  3. Paleohydrology of the southern Great Basin, with special reference to water table fluctuations beneath the Nevada Test Site during the late(?) Pleistocene

    USGS Publications Warehouse

    Winograd, Isaac Judah; Doty, Gene C.

    1980-01-01

    Knowledge of the magnitude of water-table rise during Pleistocene pluvial climates, and of the resultant shortening of groundwater flow path and reduction in unsaturated zone thickness, is mandatory for a technical evaluation of the Nevada Test Site (NTS) or other arid zone sites as repositories for high-level or transuranic radioactive wastes. The distribution of calcitic veins filling fractures in alluvium, and of tufa deposits between the Ash Meadows spring discharge area and the Nevada Test Site indicates that discharge from the regional Paleozoic carbonate aquifer during the Late( ) Pleistocene pluvial periods may have occurred at an altitude about 50 meters higher than at present and 14 kilometers northeast of Ash Meadows. Use of the underflow equation (relating discharge to transmissivity, aquifer width, and hydraulic gradient), and various assumptions regarding pluvial recharge, transmissivity, and altitude of groundwater base level, suggest possible rises in potentiometric level in the carbonate aquifer of about -90 meters beneath central Frenchman Flat. During Wisconsin time the rise probably did not exceed 30 meters. Water-level rises beneath Frenchman Flat during future pluvials are unlikely to exceed 30 meters and might even be 10 meters lower than modern levels. Neither the cited rise in potentiometric level in the regional carbonate aquifer, nor the shortened flow path during the Late( ) Pleistocene preclude utilization of the NTS as a repository for high-level or transuranic-element radioactive wastes provided other requisite conditions are met as this site. Deep water tables, attendant thick (up to several hundred meter) unsaturated zones, and long groundwater flow paths characterized the region during the Wisconsin Stage and probably throughout the Pleistocene Epoch and are likely to so characterize it during future glacial periods. (USGS)

  4. Karst connections between unconfined aquifers and the Upper Floridan aquifer in south Georgia: geophysical evidence and hydrogeological models

    NASA Astrophysics Data System (ADS)

    Thieme, D. M.; Denizman, C.

    2011-12-01

    Buried karst features in sedimentary rocks of the south Georgia Coastal Plain present a challenge for hydrogeological models of recharge and confined flow within the underlying Upper Floridan aquifer. The Withlacoochee River, the trunk stream for the area, frequently disappears into subsurface caverns as it makes its way south to join the Suwannee River in northern Florida. The Withlacoochee also receives inputs from small ponds and bays which in turn receive spring and seep groundwater inputs. We have mapped karst topography at the "top of rock" using ground-penetrating radar (GPR). Up to seven meters of relief is indicated for the paleotopography on Miocene to Pliocene rocks, contrasting with the more subdued relief of the modern landscape. Current stratigraphic and hydrogeological reconstructions do not incorporate this amount of relief or lateral variation in the confining beds. One "pipe" which is approximately four meters in diameter is being mapped in detail. We have field evidence at this location for rapid movement of surficial pond and river water with a meteoric signature through several separate strata of sedimentary rock into an aquifer in the Hawthorn formation. We use our geophysical and hydrological field evidence to constrain quantitative hydrogeological models for the flow rates into and out of both this upper aquifer and the underlying Upper Floridan aquifer, which is generally considered to be confined by the clays of the Hawthorn.

  5. Flowmeter for Clear and Translucent Fluids

    NASA Technical Reports Server (NTRS)

    White, P. R.

    1985-01-01

    Transducer with only three moving parts senses flow of clear or translucent fluid. Displacement of diaphragm by force of flow detected electrooptically and displayed by panel meter or other device. Transducer used to measure flow of gasoline to automobile engine.

  6. A High-Pressure Bi-Directional Cycloid Rotor Flowmeter

    PubMed Central

    Liu, Shuo; Ding, Fan; Ding, Chuan; Man, Zaipeng

    2014-01-01

    The measurement of the flow rate of various liquids and gases is critical in industrial automation. Rotary positive displacement meters (rotary PD meters) are highly accurate flowmeters that are widely employed in engineering applications, especially in custody transfer operations and hydraulic control systems. This paper presents a high pressure rotary PD meter containing a pair of internal cycloid rotors. It has the advantages of concise structure, low pressure loss, high accuracy and low noise. The curve of the internal rotor is designed as an equidistant curtate epicycloid curve with the external rotor curve as its conjugate. The calculation method used to determine the displacement of the cycloid rotor flowmeter is discussed. A prototype was fabricated, and experiments were performed to confirm measurements over a flow range of 1–100 L/min with relative errors of less than ±0.5%. The pressure loss through the flowmeter was about 3 bar at a flow rate of 100 L/min. PMID:25196162

  7. Restoration of the Apollo 15 Heat Flow Experiment Data from 1975 to 1977

    NASA Technical Reports Server (NTRS)

    Nagihara, S.; Nakamura, Y.; Taylor, P. T.; Williams, D. R.; Kiefer, W. S.

    2017-01-01

    The Apollo 15 Heat Flow Experiment (HFE) was conducted from July 1971 through January 1977. Two heat flow probes were deployed roughly 8.5 meters apart. Probe 1 and Probe 2 penetrated to 1.4-meters and 1-meter depths into the lunar regolith, respectively. Temperatures at different depths and the surface were logged with 7.25-minute intervals and transmitted to Earth. At the conclusion of the experiment, only data obtained from July 1971 through December 1974 were processed and archived at the National Space Science Data Center (NSSDC) by the principal investigator of the experiment, Marcus Langseth of Columbia University. Langseth died in 1997. It is not known what happened to the HFE data tapes he used. Current researchers have strong interests in re-examining the HFE data for the full duration of the experiment. We have recovered and processed large portions of the Apollo 15 HFE data from 1975 through 1977 by assembling data and metadata from various sources.

  8. Aerodynamic characteristics of a Sparrow 3 missile model in the flow field of a generalized parent body at Mach 2.86

    NASA Technical Reports Server (NTRS)

    Stallings, R. L., Jr.

    1984-01-01

    Longitudinal aerodynamic characteristics of a Sparrow 3 wing control missile model were measured through a range of separation distances relative to a flat plate surface that represented the parent-body configuration. Measurements were obtained with and without two dimensional circular arc protuberances attached to the flat plate surface. The tests were conducted at a Mach number of 2.86 and a Reynolds number per meter of 6.56 million. The behavior of these longitudinal characteristics with varying separation distance in the flow field created by the flat plate and protuberance was generally as would be expected on the basis of flow field boundaries determined from the second order approximation of Friedrich. In general, varying roll angle from 0 deg to 45 deg caused no significant effect on the store separation characteristics.

  9. The InSight Mars Lander and Its Effect on the Subsurface Thermal Environment

    NASA Astrophysics Data System (ADS)

    Siegler, Matthew A.; Smrekar, Suzanne E.; Grott, Matthias; Piqueux, Sylvain; Mueller, Nils; Williams, Jean-Pierre; Plesa, Ana-Catalina; Spohn, Tilman

    2017-10-01

    The 2018 InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) Mission has the mission goal of providing insitu data for the first measurement of the geothermal heat flow of Mars. The Heat Flow and Physical Properties Package (HP3) will take thermal conductivity and thermal gradient measurements to approximately 5 m depth. By necessity, this measurement will be made within a few meters of the lander. This means that thermal perturbations from the lander will modify local surface and subsurface temperature measurements. For HP3's sensitive thermal gradient measurements, this spacecraft influence will be important to model and parameterize. Here we present a basic 3D model of thermal effects of the lander on its surroundings. Though lander perturbations significantly alter subsurface temperatures, a successful thermal gradient measurement will be possible in all thermal conditions by proper (>3 m depth) placement of the heat flow probe.

  10. Effectiveness of Miles-Per-Gallon Meters as a Means to Conserve Gasoline in Automobiles

    DOT National Transportation Integrated Search

    1976-10-01

    This report is an assessment of fuel flow instruments reading directly in miles per gallon (mpg). It describes currently available mpg meters, their installation, utility, and safety and presents an analysis of potential cost savings. It discusses me...

  11. Experimental aerodynamic and acoustic model testing of the Variable Cycle Engine (VCE) testbed coannular exhaust nozzle system

    NASA Technical Reports Server (NTRS)

    Nelson, D. P.; Morris, P. M.

    1980-01-01

    Aerodynamic performance and jet noise characteristics of a one sixth scale model of the variable cycle engine testbed exhaust system were obtained in a series of static tests over a range of simulated engine operating conditions. Model acoustic data were acquired. Data were compared to predictions of coannular model nozzle performance. The model, tested with an without a hardwall ejector, had a total flow area equivalent to a 0.127 meter (5 inch) diameter conical nozzle with a 0.65 fan to primary nozzle area ratio and a 0.82 fan nozzle radius ratio. Fan stream temperatures and velocities were varied from 422 K to 1089 K (760 R to 1960 R) and 434 to 755 meters per second (1423 to 2477 feet per second). Primary stream properties were varied from 589 to 1089 K (1060 R to 1960 R) and 353 to 600 meters per second (1158 to 1968 feet per second). Exhaust plume velocity surveys were conducted at one operating condition with and without the ejector installed. Thirty aerodynamic performance data points were obtained with an unheated air supply. Fan nozzle pressure ratio was varied from 1.8 to 3.2 at a constant primary pressure ratio of 1.6; primary pressure ratio was varied from 1.4 to 2.4 while holding fan pressure ratio constant at 2.4. Operation with the ejector increased nozzle thrust coefficient 0.2 to 0.4 percent.

  12. A Probabilistic Model of Meter Perception: Simulating Enculturation.

    PubMed

    van der Weij, Bastiaan; Pearce, Marcus T; Honing, Henkjan

    2017-01-01

    Enculturation is known to shape the perception of meter in music but this is not explicitly accounted for by current cognitive models of meter perception. We hypothesize that the induction of meter is a result of predictive coding: interpreting onsets in a rhythm relative to a periodic meter facilitates prediction of future onsets. Such prediction, we hypothesize, is based on previous exposure to rhythms. As such, predictive coding provides a possible explanation for the way meter perception is shaped by the cultural environment. Based on this hypothesis, we present a probabilistic model of meter perception that uses statistical properties of the relation between rhythm and meter to infer meter from quantized rhythms. We show that our model can successfully predict annotated time signatures from quantized rhythmic patterns derived from folk melodies. Furthermore, we show that by inferring meter, our model improves prediction of the onsets of future events compared to a similar probabilistic model that does not infer meter. Finally, as a proof of concept, we demonstrate how our model can be used in a simulation of enculturation. From the results of this simulation, we derive a class of rhythms that are likely to be interpreted differently by enculturated listeners with different histories of exposure to rhythms.

  13. UNDERSTANDING HARD ROCK HYDROGEOLOGY THROUGH AN EXPERIMENTAL HYDROGEOLOGICAL PARK IN SOUTH INDIA: Site development and investigations on the major role of the fractured zone in crystalline aquifers

    NASA Astrophysics Data System (ADS)

    Ahmed, S.; Guiheneuf, N.; Boisson, A.; Marechal, J.; Chandra, S.; Dewandel, B.; Perrin, J.

    2012-12-01

    In water stressed south India most of the groundwater used for irrigation is pumped from crystalline rocks aquifers. In those structures groundwater flow dominantly occur in a shallow higher-permeability zone that overlies a deeper lower-permeability zone hosting little flow. The fractured zone of the weathering profile plays an important role for groundwater. In order to understand clearly this impact on water availability and quality changes the Experimental Hydrogeological Park at Choutuppal, Andhra Pradesh, India is developed in the framework of the SORE H+ network. Several hydraulic tests (injection, flowmeter profiles, single-packer tests…) and geophysical measurements (ERT, Borehole logging…) are carried out on the site in order to characterize the depth-dependence of hydrodynamic parameters in the Indian Archean granite. Specific investigation on a borewell through packer tests demonstrate that the most conductive part of the aquifer corresponds to the upper part of the fractured layer, located just below the saprolite bottom, between 15 meters and 20 meters depth. There is no highly conductive fracture beyond 20 meters depth and no indication for any conductive fracture beyond 25 meters depth. Packer tests show that the upper part of the fractured layer (15-20 m depth) is characterized by a good vertical connectivity. On the contrary, the tests carried out below 20 m depth show no vertical connectivity at all. The geometry of the fracture network and associated hydrodynamic parameters are in agreement with the conceptual model of hard-rock aquifers that derive its properties from weathering processes. The general existence of such a highly conductive structure at the top of the fractured zone has a great impact on water prospection and exploitation in such crystalline aquifers.

  14. An integrated workflow for stress and flow modelling using outcrop-derived discrete fracture networks

    NASA Astrophysics Data System (ADS)

    Bisdom, K.; Nick, H. M.; Bertotti, G.

    2017-06-01

    Fluid flow in naturally fractured reservoirs is often controlled by subseismic-scale fracture networks. Although the fracture network can be partly sampled in the direct vicinity of wells, the inter-well scale network is poorly constrained in fractured reservoir models. Outcrop analogues can provide data for populating domains of the reservoir model where no direct measurements are available. However, extracting relevant statistics from large outcrops representative of inter-well scale fracture networks remains challenging. Recent advances in outcrop imaging provide high-resolution datasets that can cover areas of several hundred by several hundred meters, i.e. the domain between adjacent wells, but even then, data from the high-resolution models is often upscaled to reservoir flow grids, resulting in loss of accuracy. We present a workflow that uses photorealistic georeferenced outcrop models to construct geomechanical and fluid flow models containing thousands of discrete fractures covering sufficiently large areas, that does not require upscaling to model permeability. This workflow seamlessly integrates geomechanical Finite Element models with flow models that take into account stress-sensitive fracture permeability and matrix flow to determine the full permeability tensor. The applicability of this workflow is illustrated using an outcropping carbonate pavement in the Potiguar basin in Brazil, from which 1082 fractures are digitised. The permeability tensor for a range of matrix permeabilities shows that conventional upscaling to effective grid properties leads to potential underestimation of the true permeability and the orientation of principal permeabilities. The presented workflow yields the full permeability tensor model of discrete fracture networks with stress-induced apertures, instead of relying on effective properties as most conventional flow models do.

  15. Estimating Water Fluxes Across the Sediment-Water Interface in the Lower Merced River, California

    USGS Publications Warehouse

    Zamora, Celia

    2008-01-01

    The lower Merced River Basin was chosen by the U.S. Geological Survey?s (USGS) National Water Quality Assessment Program (NAWQA) to be included in a national study on how hydrological processes and agricultural practices interact to affect the transport and fate of agricultural chemicals. As part of this effort, surface-water?ground-water (sw?gw) interactions were studied in an instrumented 100-m reach on the lower Merced River. This study focused on estimating vertical rates of exchange across the sediment?water interface by direct measurement using seepage meters and by using temperature as a tracer coupled with numerical modeling. Temperature loggers and pressure transducers were placed in monitoring wells within the streambed and in the river to continuously monitor temperature and hydraulic head every 15 minutes from March 2004 to October 2005. One-dimensional modeling of heat and water flow was used to interpret the temperature and head observations and deduce the sw?gw fluxes using the USGS numerical model, VS2DH, which simulates variably saturated water flow and solves the energy transport equation. Results of the modeling effort indicate that the Merced River at the study reach is generally a slightly gaining stream with small head differences (cm) between the surface water and ground water, with flow reversals occurring during high streamflow events. The average vertical flux across the sediment?water interface was 0.4?2.2 cm/day, and the range of hydraulic conductivities was 1?10 m/day. Seepage meters generally failed to provide accurate data in this high-energy system because of slow seepage rates and a moving streambed resulting in scour or burial of the seepage meters. Estimates of streambed hydraulic conductivity were also made using grain-size analysis and slug tests. Estimated hydraulic conductivity for the upstream transect determined using slug tests ranged from 40 to 250 m/day, whereas the downstream transect ranged from 10 to 100 m/day. The range in variability was a result of position along each transect. A relative percent difference was used to describe the variability in estimates of hydraulic conductivity by grain-size analysis and slug test. Variability in applied methods at the upstream transect ranged from 0 to 9 percent, whereas the downstream transect showed greater variability, with a range of 80 to 133 percent.

  16. Application of a laser interferometer skin-friction meter in complex flows

    NASA Technical Reports Server (NTRS)

    Monson, D. J.; Driver, D. M.; Szodruch, J.

    1981-01-01

    The application of a nonintrusive laser-interferometer skin-friction meter, which measures skin friction with a remotely located laser interferometer that monitors the thickness change of a thin oil film, is extended both experimentally and theoretically to several complex wind-tunnel flows. These include two-dimensional seperated and reattached subsonic flows with large pressure and shear gradients, and two and three-dimensional supersonic flows at high Reynolds number, which include variable wall temperatures and cross-flows. In addition, it is found that the instrument can provide an accurate location of the mean reattachment length for separated flows. Results show that levels up to 120 N/sq m, or 40 times higher than previous tests, can be obtained, despite encountering some limits to the method for very high skin-friction levels. It is concluded that these results establish the utility of this instrument for measuring skin friction in a wide variety of flows of interest in aerodynamic testing.

  17. Measuring Taylor Slough boundary and internal flows, Everglades National Park, Florida

    USGS Publications Warehouse

    Tillis, G.M.

    2001-01-01

    Four intensive data-collection efforts, intended to represent the spectrum of precipitation events and associated flow conditions, were conducted during 1997 and 1998 in the Taylor Slough Basin, Everglades National Park. Flow velocities were measured by newly developed, portable Acoustic Doppler Velocity meters along three transects bisecting the Taylor Slough Basin from east to west, roughly perpendicular to the centerline axis of the slough as well as a fourth transect along the slough's axis. These meters provided the required levels of accuracy in flow-velocity measurements while enabling the rapid collection of multiple time series of flow data at remote sites. Concurrently, flow measurements were made along bordering road culverts and under L-31W and Taylor Slough bridges. Flows across the study area's boundaries provided net flow of water into the system and transect measurements provided flow data within the basin. Collected data are available through the World Wide Web (http://sofia.usgs.gov/projects/flow_velocity/). The high-water and low-water events corresponded with the highest and lowest flow velocities, respectively. The July 1998 data had lower than expected flow velocities and, in some cases, strong winds reversed flow direction.

  18. A high-resolution large-eddy simulation of turbulent flow within and above urban-like canopies

    NASA Astrophysics Data System (ADS)

    Maché, M.; Calmet, I.; Sini, J.-F.

    2009-09-01

    The urban microclimate is a result of the interactions between regional climatology, morphology of urban fabric and thermo-radiative and hydric properties of the materials constituting the urban surfaces. Modern urban planning tries to compact cities for avoiding spreading of the town area in order to reduce the need of transports. The climatic effects of this politic are not well known yet. This work is the first step of a study whose main purpose is to propose an urban planning politic which considers the urban heat island within the context of the climate change. Therefore it aims to understand the effects of building configuration on the momentum, heat and humidity turbulent transfers. Urban structures are quite heterogeneous and complex. To analyse the interactions between urban canopies and the atmosphere, the resolution has to be high enough that mean flow characteristics between the buildings can be observed as well as turbulent structures that develop above roof level. For that purpose, the Large-Eddy Simulation atmospheric model ARPS (Advanced Regional Prediction System) is employed. The subgrid scales are modelled by means of the resolution of an equation for the subgrid-scale turbulent kinetic energy. The version used is this study is based on the developments of Dupont & Brunet (2008) who introduced a drag force approach to simulate the influence of the vegetal covers on the low atmosphere. The application of this model on urban canopies requires adjusting the drag coefficient (Cd) in function of the frontal density (Af) and of the building arrangement. Its dependency on configuration (staggered or aligned arrays) and on frontal density is investigated. In order to put in light the main characteristics of the flow field and to validate the model in urban configurations, the turbulent flow above arrays of obstacles is investigated here for different arrangements and packing densities. The grid spacing is set to a few tens of meters in both horizontal directions and one meter in vertical direction, within the canopy. Above the canopy, grids are stretched vertically to reach four meters in average. The surface density Af is calculated in function of the geometry of the obstacles present in a grid cell. The effect of Cd values on the turbulent statistics is compared with results from wind tunnel experiments or building resolving simulations. The ability of the model to reproduce the major turbulent organized structures above the canopy and the influence of the building configuration is also studied, in terms of intensity, size and orientation of the structures. Further research will be done to investigate the effect of configuration of buildings with more complex geometries, like variable building height, on turbulent flow characteristics. To understand the climatologic features of a real city this approach will be completed by the introduction of a parametrization for heat and humidity exchanges inside the canopy.

  19. Experimental validation of a 2D overland flow model using high resolution water depth and velocity data

    NASA Astrophysics Data System (ADS)

    Cea, L.; Legout, C.; Darboux, F.; Esteves, M.; Nord, G.

    2014-05-01

    This paper presents a validation of a two-dimensional overland flow model using empirical laboratory data. Unlike previous publications in which model performance is evaluated as the ability to predict an outlet hydrograph, we use high resolution 2D water depth and velocity data to analyze to what degree the model is able to reproduce the spatial distribution of these variables. Several overland flow conditions over two impervious surfaces of the order of one square meter with different micro and macro-roughness characteristics are studied. The first surface is a simplified representation of a sinusoidal terrain with three crests and furrows, while the second one is a mould of a real agricultural seedbed terrain. We analyze four different bed friction parameterizations and we show that the performance of formulations which consider the transition between laminar, smooth turbulent and rough turbulent flow do not improve the results obtained with Manning or Keulegan formulas for rough turbulent flow. The simulations performed show that using Keulegan formula with a physically-based definition of the bed roughness coefficient, a two-dimensional shallow water model is able to reproduce satisfactorily the flow hydrodynamics. It is shown that, even if the resolution of the topography data and numerical mesh are high enough to include all the small scale features of the bed surface, the roughness coefficient must account for the macro-roughness characteristics of the terrain in order to correctly reproduce the flow hydrodynamics.

  20. The performance & flow visualization studies of three-dimensional (3-D) wind turbine blade models

    NASA Astrophysics Data System (ADS)

    Sutrisno, Prajitno, Purnomo, W., Setyawan B.

    2016-06-01

    Recently, studies on the design of 3-D wind turbine blades have a less attention even though 3-D blade products are widely sold. In contrary, advanced studies in 3-D helicopter blade tip have been studied rigorously. Studies in wind turbine blade modeling are mostly assumed that blade spanwise sections behave as independent two-dimensional airfoils, implying that there is no exchange of momentum in the spanwise direction. Moreover, flow visualization experiments are infrequently conducted. Therefore, a modeling study of wind turbine blade with visualization experiment is needed to be improved to obtain a better understanding. The purpose of this study is to investigate the performance of 3-D wind turbine blade models with backward-forward swept and verify the flow patterns using flow visualization. In this research, the blade models are constructed based on the twist and chord distributions following Schmitz's formula. Forward and backward swept are added to the rotating blades. Based on this, the additional swept would enhance or diminish outward flow disturbance or stall development propagation on the spanwise blade surfaces to give better blade design. Some combinations, i. e., b lades with backward swept, provide a better 3-D favorable rotational force of the rotor system. The performance of the 3-D wind turbine system model is measured by a torque meter, employing Prony's braking system. Furthermore, the 3-D flow patterns around the rotating blade models are investigated by applying "tuft-visualization technique", to study the appearance of laminar, separated, and boundary layer flow patterns surrounding the 3-dimentional blade system.

  1. Hydrometry's classical and Innovative methods and tools comparison for Stara river flows at Agios Germanos monitoring station in north-west Greece.

    NASA Astrophysics Data System (ADS)

    Filintas, Agathos, , Dr; Hatzigiannakis, Evagellos, , Dr; Arampatzis, George, , Dr; Ilias, Andreas; Panagopoulos, Andreas, , Dr; Hatzispiroglou, Ioannis

    2015-04-01

    The aim of the present study is a thorough comparison of hydrometry's conventional and innovative methods-tools for river flow monitoring. A case study was conducted in Stara river at Agios Germanos monitoring station (northwest Greece), in order to investigate possible deviations between conventional and innovative methods-tools on river flow velocity and discharge. For this study, two flowmeters were used, which manufac-tured in 2013 (OTT Messtechnik Gmbh, 2013), as follows: a) A conventional propeller flow velocity meter (OTT-Model C2) which is a me-chanical current flow meter with a certification of calibration BARGO, operated with a rod and a relocating device, along with a digital measuring device including an elec-tronic flow calculator, data logger and real time control display unit. The flowmeter has a measurement velocity range 0.025-4.000 m/s. b) An innovative electromagnetic flowmeter (OTT-Model MF pro) which it is con-sisted of a compact and light-weight sensor and a robust handheld unit. Both system components are designed to be attached to conventional wading rods. The electromag-netic flowmeter uses Faraday's Law of electromagnetic induction to measure the process flow. When an electrically conductive fluid flows along the meter, an electrode voltage is induced between a pair of electrodes placed at right angles to the direction of mag-netic field. The electrode voltage is directly proportional to the average fluid velocity. The electromagnetic flowmeter was operated with a rod and relocating device, along with a digital measuring device with various logging and graphical capabilities and vari-ous methods of velocity measurement (ISO/USGS standards). The flowmeter has a measurement velocity range 0.000-6.000 m/s. The river flow data were averaged over a pair measurement of 60+60 seconds and the measured river water flow velocity, depths and widths of the segments were used for the estimation of cross-section's mean flow velocity in each measured segment. Then it was used the mid-section method for the overall discharge calculation of all segments flow area. The cross-section characteristics, the river flow velocity of segments and the mean water flow velocity and discharge total profile were measured, calculated and an-notated respectively. A series of concurrent conventional and innovative (electromag-netic) flow measurements were performed during 2014. The results and statistical analysis showed that Froude number during the measurement period in all cases was Fr<1 which means that the water flow of the Stara river is classified as subcritical flow. The 12 months' study showed various advantages for the elec-tromagnetic sensor that is virtually maintenance-free because there are no moving parts, no calibration was required in practice, and it can be used even in the lowest water ve-locities from 0.000 m/s. Moreover, based on the concurrent hydromeasurements of the Stara River, on the velocity and discharge modelling and the statistical analysis, it was found that there was not a significant statistical difference (α=0.05) between mean velocity measured with a) conventional and b) electromagnetic method which seems to be more accurate in low velocities where a significant statistical difference was found. Acknowledgments Data in this study are collected in the framework of the elaboration of the national water resources monitoring network, supervised by the Special Secretariat for Water-Hellenic Ministry for the Environment and Climate Change. This project is elaborated in the framework of the operational program "Environment and Sustainable Development" which is co-funded by the National Strategic Reference Framework (NSRF) and the Public Investment Program (PIP).

  2. 40 CFR Table 2 to Subpart D of... - TRE Parameters for NSPS Referencing Subpartsa

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...? Net heating value(MJ/scm)b Vent stream flow rate (scm/min)c Values of terms for TRE equation: TRE=A... § 65.64(h). b MJ/scm = mega Joules per standard cubic meter. c scm/min = standard cubic meters per...

  3. 40 CFR Table 2 to Subpart D of... - TRE Parameters for NSPS Referencing Subpartsa

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...? Net heating value(MJ/scm)b Vent stream flow rate (scm/min)c Values of terms for TRE equation: TRE=A... § 65.64(h). b MJ/scm = mega Joules per standard cubic meter. c scm/min = standard cubic meters per...

  4. Integrated hydrologic model of Pajaro Valley, Santa Cruz and Monterey Counties, California

    USGS Publications Warehouse

    Hanson, Randall T.; Schmid, Wolfgang; Faunt, Claudia C.; Lear, Jonathan; Lockwood, Brian

    2014-01-01

    The HS-ASR was simulated for the years 2002–09, and replaced about about 1,290 acre-ft of coastal pumpage. This was combined with the simulation of additional 6,200 acre-ft of deliveries from supplemental wells, recycled water, and city connection deliveries through the CDS that also supplanted some coastal pumpage. Total simulated deliveries were 7,350 acre-ft of the 7,500 acre-ft of reported deliveries for the period 2002-09. The completed CDS should be capable of delivering about 8.8 million cubic meters (7,150 acre-ft) of water per year to coastal farms within the Pajaro Valley, if all the local supply components were fully available for this purpose. This would represent about 15 percent of the 48,300 acre-ft (59.6 million cubic meters) average agricultural pumpage for the period 2005 to 2009. Combined with the potential capture and reuse of some of the return flows and tile-drain flows, this could represent an almost 70 percent reduction of average overdraft for the entire valley and a large part of the coastal pumpage that induces seawater intrusion.

  5. Is hyporheic flow an indicator for salmonid spawning site selection?

    NASA Astrophysics Data System (ADS)

    Benjankar, R. M.; Tonina, D.; Marzadri, A.; McKean, J. A.; Isaak, D.

    2015-12-01

    Several studies have investigated the role of hydraulic variables in the selection of spawning sites by salmonids. Some recent studies suggest that the intensity of the ambient hyporheic flow, that present without a salmon egg pocket, is a cue for spawning site selection, but others have argued against it. We tested this hypothesis by using a unique dataset of field surveyed spawning site locations and an unprecedented meter-scale resolution bathymetry of a 13.5 km long reach of Bear Valley Creek (Idaho, USA), an important Chinook salmon spawning stream. We used a two-dimensional surface water model to quantify stream hydraulics and a three-dimensional hyporheic model to quantify the hyporheic flows. Our results show that the intensity of ambient hyporheic flows is not a statistically significant variable for spawning site selection. Conversely, the intensity of the water surface curvature and the habitat quality, quantified as a function of stream hydraulics and morphology, are the most important variables for salmonid spawning site selection. KEY WORDS: Salmonid spawning habitat, pool-riffle system, habitat quality, surface water curvature, hyporheic flow

  6. A comparison between red and infrared light for recording pulpal blood flow from human anterior teeth with a laser Doppler flow meter.

    PubMed

    Kijsamanmith, Kanittha; Timpawat, Siriporn; Vongsavan, Noppakun; Matthews, Bruce

    2011-06-01

    To compare red (635 nm) and infrared (780 nm) light for recording pulpal blood flow from human anterior teeth with a laser Doppler flow meter. Recordings were made from 7 healthy teeth in 5 subjects (aged 22-55 years) using a laser Doppler flow meter (Periflux 4001) equipped with both red and infrared lasers. Average blood flow signals were obtained with both light sources alternately from each tooth under five conditions: intact tooth without opaque rubber dam, intact tooth with dam, after injecting local anaesthetic (3% Mepivacaine) (LA) over the apex of the tooth and cavity preparation to almost expose the pulp, after removal and replacement of the pulp, and with the root canal empty. With infrared light, because of technical limitations, data were obtained for the first three conditions only. The dam significantly decreased the mean blood flow by 82%. Injecting LA and cavity preparation had no significant effect. With red light, dam produced a decrease of 56%, and the resulting signal was reduced by 33% after LA and cavity preparation. The remaining signal fell by 46% after pulp removal and replacement. This contribution of the pulp is similar to that recorded previously with infrared light. There was no significant further change when the pulp was finally removed. The importance of using opaque rubber dam is confirmed. With dam, there is no advantage to using red rather than infrared light, and in each case the pulp contributes less than 50% to the blood flow signal. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Installation effects of long-duct pylon-mounted nacelles on a twin-jet transport model with swept supercritical wing

    NASA Technical Reports Server (NTRS)

    Lee, E. E., Jr.; Pendergraft, O. C., Jr.

    1985-01-01

    The installation interference effects of an underwing-mounted, long duct, turbofan nacelle were evaluated in the Langley 16-Foot Transonic Tunnel with two different pylon shapes installed on a twin engine transport model having a supercritical wing swept 30 deg. Wing, pylon, and nacelle pressures and overall model force data were obtained at Mach numbers from 0.70 to 0.83 and nominal angles of attack from -2 deg to 4 deg at an average unit Reynolds number of 11.9 x 1,000,000 per meter. The results show that adding the long duct nacelles to the supercritical wing, in the near sonic flow field, changed the magnitude and direction of flow velocities over the entire span, significantly reduced cruise lift, and caused large interference drag on the nacelle afterbody.

  8. Geosat Data Assimilation with Application to the Eastern North Atlantic

    NASA Technical Reports Server (NTRS)

    Stammer, Detlef

    1997-01-01

    An attempt is made to determine the three-dimensional ocean circulation from satellite altimeter measurements by assimilating Geosat sea surface height data into an eddy-resolving QuasiGeostrophic (QG) model of the eastern North Atlantic Ocean. Results are tested against independent information from hydrographic field observations and moored current meter data collected during the Geosat ERM. The comparison supports the concept of inferring aspects of the three-dimensional flow field from sea surface height observations by combining altimetric measurements with the dynamics of ocean circulation models. A Holland-type QG model with open boundaries is set up on a 2000 km X 2000 km domain of the eastern North Atlantic between 25 deg. and 45 deg. N, 32 deg. and 8 deg. W. By using a simple nudging technique, about two years of Geosat altimeter data are assimilated into the model every five days as space-time objective analyses on the model grid. The error information resulting from the analysis is used during the assimilation procedure to account for data uncertainties. Results show an intense eddy field, which in the surface layer interacts with a meandering Azores Front. Compared to Geosat, the model leads to smoothed fields that follow the observations. Model simulations are significantly correlated with hydrographic data from March 1988 and June 1989, both close to the surface and in the subsurface. Good agreement is also found between the model velocity fields and moored current meter data in the top two model layers. The agreement is visually weak in the bottom layer, although a coherence analysis reveals an agreement between the model simulation and current meter data over the full water column at periods exceeding 80 days.

  9. Development of the Coastal Storm Modeling System (CoSMoS) for predicting the impact of storms on high-energy, active-margin coasts

    USGS Publications Warehouse

    Barnard, Patrick; Maarten van Ormondt,; Erikson, Li H.; Jodi Eshleman,; Hapke, Cheryl J.; Peter Ruggiero,; Peter Adams,; Foxgrover, Amy C.

    2014-01-01

    The Coastal Storm Modeling System (CoSMoS) applies a predominantly deterministic framework to make detailed predictions (meter scale) of storm-induced coastal flooding, erosion, and cliff failures over large geographic scales (100s of kilometers). CoSMoS was developed for hindcast studies, operational applications (i.e., nowcasts and multiday forecasts), and future climate scenarios (i.e., sea-level rise + storms) to provide emergency responders and coastal planners with critical storm hazards information that may be used to increase public safety, mitigate physical damages, and more effectively manage and allocate resources within complex coastal settings. The prototype system, developed for the California coast, uses the global WAVEWATCH III wave model, the TOPEX/Poseidon satellite altimetry-based global tide model, and atmospheric-forcing data from either the US National Weather Service (operational mode) or Global Climate Models (future climate mode), to determine regional wave and water-level boundary conditions. These physical processes are dynamically downscaled using a series of nested Delft3D-WAVE (SWAN) and Delft3D-FLOW (FLOW) models and linked at the coast to tightly spaced XBeach (eXtreme Beach) cross-shore profile models and a Bayesian probabilistic cliff failure model. Hindcast testing demonstrates that, despite uncertainties in preexisting beach morphology over the ~500 km alongshore extent of the pilot study area, CoSMoS effectively identifies discrete sections of the coast (100s of meters) that are vulnerable to coastal hazards under a range of current and future oceanographic forcing conditions, and is therefore an effective tool for operational and future climate scenario planning.

  10. Emergency assessment of post-fire debris-flow hazards for the 2013 Springs Fire, Ventura County, California

    USGS Publications Warehouse

    Staley, Dennis M.

    2014-01-01

    Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can produce dangerous flash floods and debris flows. In this report, empirical models are used to predict the probability and magnitude of debris-flow occurrence in response to a 10-year rainstorm for the 2013 Springs fire in Ventura County, California. Overall, the models predict a relatively high probability (60–80 percent) of debris flow for 9 of the 99 drainage basins in the burn area in response to a 10-year recurrence interval design storm. Predictions of debris-flow volume suggest that debris flows may entrain a significant volume of material, with 28 of the 99 basins identified as having potential debris-flow volumes greater than 10,000 cubic meters. These results of the relative combined hazard analysis suggest there is a moderate likelihood of significant debris-flow hazard within and downstream of the burn area for nearby populations, infrastructure, wildlife, and water resources. Given these findings, we recommend that residents, emergency managers, and public works departments pay close attention to weather forecasts and National Weather Service-issued Debris Flow and Flash Flood Outlooks, Watches, and Warnings, and that residents adhere to any evacuation orders.

  11. Venturi flow meter and Electrical Capacitance Probe in a horizontal two-phase flow

    NASA Astrophysics Data System (ADS)

    Monni, G.; Caramello, M.; De Salve, M.; Panella, B.

    2015-11-01

    The paper presents the results obtained with a spool piece (SP) made of a Venturi flow meter (VMF) and an Electrical Capacitance Probe (ECP) in stratified two-phase flow. The objective is to determine the relationship between the test measurements and the physical characteristics of the flow such as superficial velocities, density and void fraction. The outputs of the ECP are electrical signals proportional to the void fraction between the electrodes; the parameters measured by the VFM are the total and the irreversible pressure losses of the two- phase mixture. The fluids are air and demineralized water at ambient conditions. The flow rates are in the range of 0,065-0,099 kg/s for air and 0- 0,039 kg/s (0-140 l/h) for water. The flow patterns recognized during the experiments are stratified, dispersed and annular flow. The presence of the VFM plays an important role on the alteration of the flow pattern due to wall flow detachment phenomena. The signals of differential pressure of the VFM in horizontal configuration are strongly dependent on the superficial velocities and on the flow pattern because of a lower symmetry of the flow with respect to the vertical configuration.

  12. Quantification of fish habitat in selected reaches of the Marmaton and Marais des Cygnes Rivers, Missouri

    USGS Publications Warehouse

    Heimann, David C.; Richards, Joseph M.; Brewer, Shannon K.; Norman, Richard D.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the Missouri Department of Conservation, undertook a study to quantify fish habitat by using relations between streamflow and the spatial and temporal distributions of fish habitat at five sites in the Marmaton and Marais des Cygnes Rivers in western Missouri. Twenty-six fish habitat categories were selected for nine species under varying seasonal (spring, summer, and fall), diel (summer day and night), and life-stage (spawning, juvenile, and adult) conditions. Physical habitat characteristics were determined for each category using depth, velocity, and channel substrate criteria. Continuous streamflow data were then combined with the habitat-streamflow relations to compile a habitat time series for each habitat category at each site. Fish habitat categories were assessed as to their vulnerability to habitat alteration based on critical life stages (spawning and juvenile rearing periods) and susceptibility to habitat limitations from dewatering or high flows. Species categories representing critical life stages with physical habitat limitations represent likely bottlenecks in fish populations. Categories with potential bottlenecks can serve as indicator categories and aid managers when determining the flows necessary for maintaining these habitats under altered flow regimes. The relation between the area of each habitat category and streamflow differed greatly between category, season, and stream reach. No single flow maximized selected habitat area for all categories or even for all species/category within a particular season at a site. However, some similarities were noted among habitat characteristics, including the streamflow range for which habitat availability is maximized and the range of streamflows for which a habitat category area is available at the Marmaton River sites. A monthly habitat time series was created for all 26 habitat categories at two Marmaton River sites. A daily habitat time series was created at three Marais des Cygnes River sites for two periods: 1941 through 1963 (pre-regulation) and 1982 through 2003 (post-regulation). The habitat category with the highest median area in spring was paddlefish (Polyodon spathula) with normalized areas of up to 2,000 square meters per 100 meters of stream channel. Flathead catfish (Pylodictis olivaris) habitat area generally was the category area most available in summer and fall. Differences in daily selected habitat area time series between pre- and post-regulation time periods varied by species/category and by site. For instance, whereas there was a decline in the distribution of spring spawning habitat for suckermouth minnow (Phenacobius mirabilis) and slenderhead darter (Percina phoxocephala) from pre- to post-regulation periods at all three sites, the 25 to 75 percentile habitat area substantially increased for paddlefish under post-regulation conditions. Potential habitat area for most species was maximized at the Marmaton River sites at flows of about 1 to 10 cubic meters per second, whereas median monthly streamflows ranged from less than 1 to 20 cubic meters per second depending on site and season. Paddlefish habitat was available beginning at higher flows than other categories (4 to 7 cubic meters per second) and also maximized at higher flows (greater than 50 to 100 cubic meters per second). Selected potential habitat area was maximized for most species at the Marais des Cygnes River sites at flows of about 1 to 50 cubic meters per second, whereas median monthly streamflows ranged from 4 to 55 cubic meters per second depending on site and season. The range of streamflows for which selected habitat area was available in summer and fall was substantially less at the channelized Marais des Cygnes River site when compared to the non-channelized sites, and, therefore, the susceptibility of categories to high-flow habitat limitations was greater at this site. The channelized reach was more unifor

  13. Effect of a levee setback on aquatic resources using two-dimensional flow and bioenergetics models

    USGS Publications Warehouse

    Black, Robert W.; Czuba, Christiana R.; Magirl, Christopher S.; McCarthy, Sarah; Berge, Hans; Comanor, Kyle

    2016-04-05

    Watershed restoration is the focus of many resource managers and can include a multitude of restoration actions each with specific restoration objectives. For the White River flowing through the cities of Pacific and Sumner, Washington, a levee setback has been proposed to reconnect the river with its historical floodplain to help reduce flood risks, as well as provide increased habitat for federally listed species of salmonids. The study presented here documents the use of a modeling framework that integrates two-dimensional hydraulic modeling with process-based bioenergetics modeling for predicting how changes in flow from reconnecting the river with its floodplain affects invertebrate drift density and the net rate of energy intake of juvenile salmonids. Modeling results were calculated for flows of 25.9 and 49.3 cubic meters per second during the spring, summer, and fall. Predicted hypothetical future mean velocities and depths were significantly lower and more variable when compared to current conditions. The abundance of low energetic cost and positive growth locations for salmonids were predicted to increase significantly in the study reach following floodplain reconnection, particularly during the summer. This modeling framework presents a viable approach for evaluating the potential fisheries benefits of reconnecting a river to its historical floodplain that integrates our understanding of hydraulic, geomorphology, and organismal biology.

  14. Flowing-water optical power meter for primary-standard, multi-kilowatt laser power measurements

    NASA Astrophysics Data System (ADS)

    Williams, P. A.; Hadler, J. A.; Cromer, C.; West, J.; Li, X.; Lehman, J. H.

    2018-06-01

    A primary-standard flowing-water optical power meter for measuring multi-kilowatt laser emission has been built and operated. The design and operational details of this primary standard are described, and a full uncertainty analysis is provided covering the measurement range from 1–10 kW with an expanded uncertainty of 1.2%. Validating measurements at 5 kW and 10 kW show agreement with other measurement techniques to within the measurement uncertainty. This work of the U.S. Government is not subject to U.S. copyright.

  15. Anomaly Detection in Test Equipment via Sliding Mode Observers

    NASA Technical Reports Server (NTRS)

    Solano, Wanda M.; Drakunov, Sergey V.

    2012-01-01

    Nonlinear observers were originally developed based on the ideas of variable structure control, and for the purpose of detecting disturbances in complex systems. In this anomaly detection application, these observers were designed for estimating the distributed state of fluid flow in a pipe described by a class of advection equations. The observer algorithm uses collected data in a piping system to estimate the distributed system state (pressure and velocity along a pipe containing liquid gas propellant flow) using only boundary measurements. These estimates are then used to further estimate and localize possible anomalies such as leaks or foreign objects, and instrumentation metering problems such as incorrect flow meter orifice plate size. The observer algorithm has the following parts: a mathematical model of the fluid flow, observer control algorithm, and an anomaly identification algorithm. The main functional operation of the algorithm is in creating the sliding mode in the observer system implemented as software. Once the sliding mode starts in the system, the equivalent value of the discontinuous function in sliding mode can be obtained by filtering out the high-frequency chattering component. In control theory, "observers" are dynamic algorithms for the online estimation of the current state of a dynamic system by measurements of an output of the system. Classical linear observers can provide optimal estimates of a system state in case of uncertainty modeled by white noise. For nonlinear cases, the theory of nonlinear observers has been developed and its success is mainly due to the sliding mode approach. Using the mathematical theory of variable structure systems with sliding modes, the observer algorithm is designed in such a way that it steers the output of the model to the output of the system obtained via a variety of sensors, in spite of possible mismatches between the assumed model and actual system. The unique properties of sliding mode control allow not only control of the model internal states to the states of the real-life system, but also identification of the disturbance or anomaly that may occur.

  16. Smart Grid Integrity Attacks: Characterizations and Countermeasures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Annarita Giani; Eilyan Bitar; Miles McQueen

    2011-10-01

    Real power injections at loads and generators, and real power flows on selected lines in a transmission network are monitored, transmitted over a SCADA network to the system operator, and used in state estimation algorithms to make dispatch, re-balance and other energy management system [EMS] decisions. Coordinated cyber attacks of power meter readings can be arranged to be undetectable by any bad data detection algorithm. These unobservable attacks present a serious threat to grid operations. Of particular interest are sparse attacks that involve the compromise of a modest number of meter readings. An efficient algorithm to find all unobservable attacksmore » [under standard DC load flow approximations] involving the compromise of exactly two power injection meters and an arbitrary number of power meters on lines is presented. This requires O(n2m) flops for a power system with n buses and m line meters. If all lines are metered, there exist canonical forms that characterize all 3, 4, and 5-sparse unobservable attacks. These can be quickly detected in power systems using standard graph algorithms. Known secure phase measurement units [PMUs] can be used as countermeasures against an arbitrary collection of cyber attacks. Finding the minimum number of necessary PMUs is NP-hard. It is shown that p + 1 PMUs at carefully chosen buses are sufficient to neutralize a collection of p cyber attacks.« less

  17. 40 CFR 1065.248 - Gas divider.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... testing. You may use critical-flow gas dividers, capillary-tube gas dividers, or thermal-mass-meter gas... PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.248 Gas divider. (a) Application. You may...

  18. Thermal homogeneity of plastication processes in single-screw extruders

    NASA Astrophysics Data System (ADS)

    Bu, L. X.; Agbessi, Y.; Béreaux, Y.; Charmeau, J.-Y.

    2018-05-01

    Single-screw plastication, used in extrusion and in injection moulding, is a major way of processing commodity thermoplastics. During the plastication phase, the polymeric material is melted by the combined effects of shear-induced self-heating (viscous dissipation) and heat conduction coming from the barrel. In injection moulding, a high level of reliability is usually achieved that makes this process ideally suited to mass market production. Nonetheless, process fluctuations still appear that make moulded part quality control an everyday issue. In this work, we used a combined modelling of plastication, throughput calculation and laminar dispersion, to investigate if, and how, thermal fluctuations could propagate along the screw length and affect the melt homogeneity at the end of the metering section. To do this, we used plastication models to relate changes in processing parameters to changes in the plastication length. Moreover, a simple model of throughput calculation is used to relate the screw geometry, the polymer rheology and the processing parameters to get a good estimate of the mass flow rate. Hence, we found that the typical residence time in a single screw is around one tenth of the thermal diffusion time scale. This residence time is too short for the dispersion coefficient to reach a steady state, but too long to be able to neglect radial thermal diffusion and resort to a purely convective solution. Therefore, a full diffusion/convection problem has to be solved with a base flow described by the classic pressure and drag velocity field. Preliminary results already show the major importance of the processing parameters in the breakthrough curve of an arbitrary temperature fluctuation at the end of the metering section of injection moulding screw. When the flow back-pressure is high, the temperature fluctuation is spread more evenly with time, whereas a pressure drop in the flow will results in a breakthrough curve which presents a larger peak of fluctuation.

  19. Environmental Assessment for Selected Regions in the Mediterranean Sea

    DTIC Science & Technology

    1992-01-01

    derived from gravity and turbidity flows and include ash layers interbedded with hemipelagic mud. Sedimen- tation rates in these regions are on the order of...CURRENT METERS, ALBORAN I (PISTEK 1984)0& CURRENT METERS, ALBORAN III (PISTEK 1987) A DRIFTING CURRENT METERIS , ALBORAN 11 (PISTEK 1987) 0: CURRENT

  20. Applications of a laser velocimeter in the Langley 4- by 7-meter tunnel

    NASA Astrophysics Data System (ADS)

    Sellers, W. L.; Elliott, J. W.

    1982-09-01

    Applications of a laser velocimeter in the Langley 4 by 7 meter wind tunnel are discussed. The system configuration is described. The data acquisition, the laser velocimeter traversing, and the particle generating systems are discussed. Flow distribution and rotor wake applications are discussed.

  1. THE VERTICAL PLANAR MOTION MECHANISM; A DYNAMIC TEST APPARATUS FOR EVALUATING CURRENT METERS AND OTHER MARINE INSTRUMENTATION

    EPA Science Inventory

    The overall objective was to provide a dynamic test apparatus that can produce known, controlled high frequency dynamics for the evaluation of current meters and other marine instrumentation. Of primary interest is the establishment of flow sensor measurement capabilities, and he...

  2. 43 CFR 3274.11 - What must I give BLM to approve my commercial use permit application?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... configuration, including meters; (f) A schematic flow diagram of the utilization facility, including... calibration schedule of production, injection, and royalty meters; (b) A schematic diagram of the utilization... is located off the utilization site, give us a generalized schematic diagram of the electrical...

  3. 43 CFR 3274.11 - What must I give BLM to approve my commercial use permit application?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... configuration, including meters; (f) A schematic flow diagram of the utilization facility, including... calibration schedule of production, injection, and royalty meters; (b) A schematic diagram of the utilization... is located off the utilization site, give us a generalized schematic diagram of the electrical...

  4. 43 CFR 3274.11 - What must I give BLM to approve my commercial use permit application?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... configuration, including meters; (f) A schematic flow diagram of the utilization facility, including... calibration schedule of production, injection, and royalty meters; (b) A schematic diagram of the utilization... is located off the utilization site, give us a generalized schematic diagram of the electrical...

  5. 43 CFR 3274.11 - What must I give BLM to approve my commercial use permit application?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... configuration, including meters; (f) A schematic flow diagram of the utilization facility, including... calibration schedule of production, injection, and royalty meters; (b) A schematic diagram of the utilization... is located off the utilization site, give us a generalized schematic diagram of the electrical...

  6. In-Flight Aeroelastic Stability of the Thermal Protection System on the NASA HIAD, Part II: Nonlinear Theory and Extended Aerodynamics

    NASA Technical Reports Server (NTRS)

    Goldman, Benjamin D.; Dowell, Earl H.; Scott, Robert C.

    2015-01-01

    Conical shell theory and a supersonic potential flow aerodynamic theory are used to study the nonlinear pressure buckling and aeroelastic limit cycle behavior of the thermal protection system for NASA's Hypersonic Inflatable Aerodynamic Decelerator. The structural model of the thermal protection system consists of an orthotropic conical shell of the Donnell type, resting on several circumferential elastic supports. Classical Piston Theory is used initially for the aerodynamic pressure, but was found to be insufficient at low supersonic Mach numbers. Transform methods are applied to the convected wave equation for potential flow, and a time-dependent aerodynamic pressure correction factor is obtained. The Lagrangian of the shell system is formulated in terms of the generalized coordinates for all displacements and the Rayleigh-Ritz method is used to derive the governing differential-algebraic equations of motion. Aeroelastic limit cycle oscillations and buckling deformations are calculated in the time domain using a Runge-Kutta method in MATLAB. Three conical shell geometries were considered in the present analysis: a 3-meter diameter 70 deg. cone, a 3.7-meter 70 deg. cone, and a 6-meter diameter 70 deg. cone. The 6-meter configuration was loaded statically and the results were compared with an experimental load test of a 6-meter HIAD. Though agreement between theoretical and experimental strains was poor, the circumferential wrinkling phenomena observed during the experiments was captured by the theory and axial deformations were qualitatively similar in shape. With Piston Theory aerodynamics, the nonlinear flutter dynamic pressures of the 3-meter configuration were in agreement with the values calculated using linear theory, and the limit cycle amplitudes were generally on the order of the shell thickness. The effect of axial tension was studied for this configuration, and increasing tension was found to decrease the limit cycle amplitudes when the circumferential elastic supports were neglected, but resulted in more complex behavior when the supports were included. The nominal flutter dynamic pressure of the 3.7-meter configuration was significantly lower than that of the 3-meter, and it was found that two sets of natural modes coalesce to flutter modes near the same dynamic pressure. This resulted in a significant drop in the limit cycle frequencies at higher dynamic pressures, where the flutter mode with the lower frequency becomes more critical. Pre-buckling pressure loads and the aerodynamic pressure correction factor were studied for all geometries, and these effects resulted in significantly lower flutter boundaries compared with Piston Theory alone. The maximum dynamic pressure predicted by aerodynamic simulations of a proposed 3.7-meter HIAD vehicle was still lower than any of the calculated flutter dynamic pressures, suggesting that aeroelastic effects for this vehicle are of little concern.

  7. THERMAL-ENERGY STORAGE IN A DEEP SANDSTONE AQUIFER IN MINNESOTA: FIELD OBSERVATIONS AND THERMAL ENERGY-TRANSPORT MODELING.

    USGS Publications Warehouse

    Miller, R.T.

    1986-01-01

    A study of the feasibility of storing heated water in a deep sandstone aquifer in Minnesota is described. The aquifer consists of four hydraulic zones that are areally anisotropic and have average hydraulic conductivities that range from 0. 03 to 1. 2 meters per day. A preliminary axially symmetric, nonisothermal, isotropic, single-phase, radial-flow, thermal-energy-transport model was constructed to investigate the sensitivity of model simulation to various hydraulic and thermal properties of the aquifer. A three-dimensional flow and thermal-energy transport model was constructed to incorporate the areal anisotropy of the aquifer. Analytical solutions of equations describing areally anisotropic groundwater flow around a doublet-well system were used to specify model boundary conditions for simulation of heat injection. The entire heat-injection-testing period of approximately 400 days was simulated. Model-computed temperatures compared favorably with field-recorded temperatures, with differences of no more than plus or minus 8 degree C. For each test cycle, model-computed aquifer thermal efficiency, defined as total heat withdrawn divided by total heat injected, was within plus or minus 2% of the field-calculated values.

  8. A flow boiling microchannel thermosyphon for fuel cell thermal management

    NASA Astrophysics Data System (ADS)

    Garrity, Patrick Thomas

    To provide a high power density thermal management system for proton exchange membrane (PEM) fuel cell applications, a passively driven thermal management system was assembled to operate in a closed loop two-phase thermosyphon. The system has two major components; a microchannel evaporator plate and a condenser. The microchannel evaporator plate was fabricated with 56 square channels that have a 1 mm x 1 mm cross section and are 115 mm long. Experiments were conducted with a liquid cooled condenser with heat flux as the control variable. Measurements of mass flow rate, temperature field, and pressure drop have been made for the thermosyphon loop. A model is developed to predict the system characteristics such as the temperature and pressure fields, flow rate, flow regime, heat transfer coefficient, and maximum heat flux. When the system is subjected to a heat load that exceeds the maximum heat flux, an unstable flow regime is observed that causes flow reversal and eventual dryout near the evaporator plate wall. This undesirable phenomenon is modeled based on a quasi-steady state assumption, and the model is capable of predicting the heat flux at the onset of instability for quasi-steady two-phase flow. Another focus of this work is the performance of the condenser portion of the loop, which will be air cooled in practice. The aim is to reduce air side thermal resistance and increase the condenser performance, which is accomplished with extended surfaces. A testing facility is assembled to observe the air side heat transfer performance of three aluminum foam samples and three modified carbon foam samples, used as extended surfaces. The aluminum foam samples have a bulk density of 216 kilograms per cubic meter with pore sizes of 0.5, 1, and 2 mm. The modified carbon foam samples have bulk densities of 284, 317, and 400 kilograms per cubic meter and machined flow passages of 3.2 mm. in diameter. Each sample is observed under forced convection with air velocity as the control variable. Thermocouples and pressure taps are distributed axially along the test section and measurements of pressure and temperature are recorded for air velocities ranging from 1-6 meters per second. Using the Darcy-Forcheimer equation, the porosity is determined for each sample. The volumetric heat transfer coefficient is extracted by means of solving the coupled energy equations of both the solid and fluid respectively. Nusselt number is correlated with Reynolds number. The optimal foam configuration is explored based on a Coefficient of Performance, (COP), Compactness Factor (CF) and Power Density (PD). The COP is the ratio of total heat removed to electrical heat consumption of the blower, CF is the total heat removed per unit volume, and PD is the total heat removed per unit mass. These performance parameters are computed for a hypothetical heat exchanger using each foam sample at various fluid velocities. They are also compared against those for the hypothetical heat exchanger fitted with conventional louvered fins. Given a proper weighting function based on the importance of CF, COP, and PD in the condenser design, an optimal configuration for an air cooled condenser can be obtained for various operating conditions.

  9. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... rates or total flow sampled into a batch sampling system over a test interval. You may use the... rates or total raw exhaust flow over a test interval. (b) Component requirements. We recommend that you... averaging Pitot tube, or a hot-wire anemometer. Note that your overall system for measuring sample flow must...

  10. Acoustic Signatures of a Model Fan in the NASA-Lewis Anechoic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Dietrich, D. A.; Heidmann, M. F.; Abbott, J. M.

    1977-01-01

    One-third octave band and narrowband spectra and continuous directivity patterns radiated from an inlet are presented over ranges of fan operating conditions, tunnel velocity, and angle of attack. Tunnel flow markedly reduced the unsteadiness and level of the blade passage tone, revealed the cutoff design feature of the blade passage tone, and exposed a lobular directivity pattern for the second harmonic tone. The full effects of tunnel flow are shown to be complete above a tunnel velocity of 20 meters/second. The acoustic signatures are also shown to be strongly affected by fan rotational speed, fan blade loading, and inlet angle of attack.

  11. Distribution of "Compound" and "Simple" Flows in the Deccan Traps (India)

    NASA Astrophysics Data System (ADS)

    Vanderkluysen, L.; Self, S.; Jay, A. E.; Sheth, H. C.; Clarke, A. B.

    2014-12-01

    The Deccan Traps are a dominantly mafic large igneous province (LIP) that, prior to erosion, covered ~1 million km2 of west-central India with lava flows. The type sections of the Western Ghats escarpment, where the Deccan lava pile reaches a maximum reconstructed stratigraphic thickness of ~3400 m, are subdivided into eleven formations defined on chemo-stratigraphic grounds. Earlier work recognized that emplacement of Deccan basalt flows primarily occurs following two main modes: as a stack of meter-sized pāhoehoe toes and lobes, termed "compound" flows; or as inflated sheet lobes tens to hundreds of meters in width and meters to tens of meters in height, previously termed "simple" flows. Initially, the distribution of small lobes and sheet lobes in the Deccan was thought to be controlled by distance from source, but later work suggested the distribution to be mainly controlled along stratigraphic, formational boundaries, with six of the lower formations being composed exclusively of compound flows, and the upper 4-5 formations being wholly built of sheet lobes. This simple stratigraphic subdivision of lava flow morphologies has also been documented in the volcanic architecture of other LIPs, e.g., the Etendeka, the Ethiopian Traps, and in the Faeroe Islands (North Atlantic LIP). Upon examination of eight sections carefully logged along the Western Ghats, this traditional view must be challenged. Where the lower Deccan formations crop out, we found that as much as 65% of the exposed thickness (below the Khandala Formation) is made up of sheet lobes, from 40% in the Bhimashankar Formation to 75% in the Thakurvadi Formation. Near the bottom of the sequence, 25% of the Neral Formation is composed of sheet lobes ≥15 m in thickness. This distribution in lava flow morphology does not seem to be noticeably affected by the inferred distance to the source (based on the location of similar-composition dikes for each formation). Several mechanisms have been proposed to explain the development of compound flows and inflated sheet lobes, involving one or more of the following factors: underlying slope, varying effusion rate, and source geometry. Analogue experiments are currently under way to test the relative influence of each of these factors in the development of different lava flow morphologies in LIPs.

  12. The Effect of Acoustic Disturbances on the Operation of the Space Shuttle Main Engine Fuel Flowmeter

    NASA Technical Reports Server (NTRS)

    Marcu, Bogdan; Szabo, Roland; Dorney, Dan; Zoladz, Tom

    2007-01-01

    The Space Shuttle Main Engine (SSME) uses a turbine fuel flowmeter (FFM) in its Low Pressure Fuel Duct (LPFD) to measure liquid hydrogen flowrates during engine operation. The flowmeter is required to provide accurate and robust measurements of flow rates ranging from 10000 to 18000 GPM in an environment contaminated by duct vibration and duct internal acoustic disturbances. Errors exceeding 0.5% can have a significant impact on engine operation and mission completion. The accuracy of each sensor is monitored during hot-fire engine tests on the ground. Flow meters which do not meet requirements are not flown. Among other parameters, the device is screened for a specific behavior in which a small shift in the flow rate reading is registered during a period in which the actual fuel flow as measured by a facility meter does not change. Such behavior has been observed over the years for specific builds of the FFM and must be avoided or limited in magnitude in flight. Various analyses of the recorded data have been made prior to this report in an effort to understand the cause of the phenomenon; however, no conclusive cause for the shift in the instrument behavior has been found. The present report proposes an explanation of the phenomenon based on interactions between acoustic pressure disturbances in the duct and the wakes produced by the FFM flow straightener. Physical insight into the effects of acoustic plane wave disturbances was obtained using a simple analytical model. Based on that model, a series of three-dimensional unsteady viscous flow computational fluid dynamics (CFD) simulations were performed using the MSFC PHANTOM turbomachinery code. The code was customized to allow the FFM rotor speed to change at every time step according to the instantaneous fluid forces on the rotor, that, in turn, are affected by acoustic plane pressure waves propagating through the device. The results of the simulations show the variation in the rotation rate of the flowmeter due to the interaction of the flow straightener wakes and the upstream propagating acoustic waves. A detailed analysis of the acoustic disturbance effects is presented along with an assessment of the impact on measurement accuracy.

  13. In-airway molecular flow sensing: A new technology for continuous, noninvasive monitoring of oxygen consumption in critical care.

    PubMed

    Ciaffoni, Luca; O'Neill, David P; Couper, John H; Ritchie, Grant A D; Hancock, Gus; Robbins, Peter A

    2016-08-01

    There are no satisfactory methods for monitoring oxygen consumption in critical care. To address this, we adapted laser absorption spectroscopy to provide measurements of O2, CO2, and water vapor within the airway every 10 ms. The analyzer is integrated within a novel respiratory flow meter that is an order of magnitude more precise than other flow meters. Such precision, coupled with the accurate alignment of gas concentrations with respiratory flow, makes possible the determination of O2 consumption by direct integration over time of the product of O2 concentration and flow. The precision is illustrated by integrating the balance gas (N2 plus Ar) flow and showing that this exchange was near zero. Measured O2 consumption changed by <5% between air and O2 breathing. Clinical capability was illustrated by recording O2 consumption during an aortic aneurysm repair. This device now makes easy, accurate, and noninvasive measurement of O2 consumption for intubated patients in critical care possible.

  14. In-airway molecular flow sensing: A new technology for continuous, noninvasive monitoring of oxygen consumption in critical care

    PubMed Central

    Ciaffoni, Luca; O’Neill, David P.; Couper, John H.; Ritchie, Grant A. D.; Hancock, Gus; Robbins, Peter A.

    2016-01-01

    There are no satisfactory methods for monitoring oxygen consumption in critical care. To address this, we adapted laser absorption spectroscopy to provide measurements of O2, CO2, and water vapor within the airway every 10 ms. The analyzer is integrated within a novel respiratory flow meter that is an order of magnitude more precise than other flow meters. Such precision, coupled with the accurate alignment of gas concentrations with respiratory flow, makes possible the determination of O2 consumption by direct integration over time of the product of O2 concentration and flow. The precision is illustrated by integrating the balance gas (N2 plus Ar) flow and showing that this exchange was near zero. Measured O2 consumption changed by <5% between air and O2 breathing. Clinical capability was illustrated by recording O2 consumption during an aortic aneurysm repair. This device now makes easy, accurate, and noninvasive measurement of O2 consumption for intubated patients in critical care possible. PMID:27532048

  15. Comparative Analysis of Smart Meters Deployment Business Models on the Example of the Russian Federation Markets

    NASA Astrophysics Data System (ADS)

    Daminov, Ildar; Tarasova, Ekaterina; Andreeva, Tatyana; Avazov, Artur

    2016-02-01

    This paper presents the comparison of smart meter deployment business models to determine the most suitable option providing smart meters deployment. Authors consider 3 main business model of companies: distribution grid company, energy supplier (energosbyt) and metering company. The goal of the article is to compare the business models of power companies from massive smart metering roll out in power system of Russian Federation.

  16. Meter for very slow flows

    NASA Technical Reports Server (NTRS)

    Baxter, W. J., Jr.; Frant, M. S.; West, S. J.

    1978-01-01

    Solid-state sensing unit developed for use with NASA's Water-Quality Monitoring System can detect small velocity changes in slow moving fluid. Nonprotruding sensor is applicable to numerous other uses requiring sensitive measurement of slow flows.

  17. 40 CFR 1065.220 - Fuel flow meter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (a) Application. You may use fuel flow in combination with a chemical balance of carbon (or oxygen... concentrations, if the same signal is used in a chemical-balance calculation to determine work from brake...

  18. 40 CFR 1065.220 - Fuel flow meter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (a) Application. You may use fuel flow in combination with a chemical balance of carbon (or oxygen... concentrations, if the same signal is used in a chemical-balance calculation to determine work from brake...

  19. Microwave fluid flow meter

    DOEpatents

    Billeter, Thomas R.; Philipp, Lee D.; Schemmel, Richard R.

    1976-01-01

    A microwave fluid flow meter is described utilizing two spaced microwave sensors positioned along a fluid flow path. Each sensor includes a microwave cavity having a frequency of resonance dependent upon the static pressure of the fluid at the sensor locations. The resonant response of each cavity with respect to a variation in pressure of the monitored fluid is represented by a corresponding electrical output which can be calibrated into a direct pressure reading. The pressure drop between sensor locations is then correlated as a measure of fluid velocity. In the preferred embodiment the individual sensor cavities are strategically positioned outside the path of fluid flow and are designed to resonate in two distinct frequency modes yielding a measure of temperature as well as pressure. The temperature response can then be used in correcting for pressure responses of the microwave cavity encountered due to temperature fluctuations.

  20. Evapotranspiration from nonuniform surfaces - A first approach for short-term numerical weather prediction

    NASA Technical Reports Server (NTRS)

    Wetzel, Peter J.; Chang, Jy-Tai

    1988-01-01

    Observations of surface heterogeneity of soil moisture from scales of meters to hundreds of kilometers are discussed, and a relationship between grid element size and soil moisture variability is presented. An evapotranspiration model is presented which accounts for the variability of soil moisture, standing surface water, and vegetation internal and stomatal resistance to moisture flow from the soil. The mean values and standard deviations of these parameters are required as input to the model. Tests of this model against field observations are reported, and extensive sensitivity tests are presented which explore the importance of including subgrid-scale variability in an evapotranspiration model.

  1. Research on MEMS sensor in hydraulic system flow detection

    NASA Astrophysics Data System (ADS)

    Zhang, Hongpeng; Zhang, Yindong; Liu, Dong; Ji, Yulong; Jiang, Jihai; Sun, Yuqing

    2011-05-01

    With the development of mechatronics technology and fault diagnosis theory, people regard flow information much more than before. Cheap, fast and accurate flow sensors are urgently needed by hydraulic industry. So MEMS sensor, which is small, low cost, well performed and easy to integrate, will surely play an important role in this field. Based on the new method of flow measurement which was put forward by our research group, this paper completed the measurement of flow rate in hydraulic system by setting up the mathematical model, using numerical simulation method and doing physical experiment. Based on viscous fluid flow equations we deduced differential pressure-velocity model of this new sensor and did optimization on parameters. Then, we designed and manufactured the throttle and studied the velocity and pressure field inside the sensor by FLUENT. Also in simulation we get the differential pressure-velocity curve .The model machine was simulated too to direct experiment. In the static experiments we calibrated the MEMS sensing element and built some sample sensors. Then in a hydraulic testing system we compared the sensor signal with a turbine meter. It presented good linearity and could meet general hydraulic system use. Based on the CFD curves, we analyzed the error reasons and made some suggestion to improve. In the dynamic test, we confirmed this sensor can realize high frequency flow detection by a 7 piston-pump.

  2. Research on MEMS sensor in hydraulic system flow detection

    NASA Astrophysics Data System (ADS)

    Zhang, Hongpeng; Zhang, Yindong; Liu, Dong; Ji, Yulong; Jiang, Jihai; Sun, Yuqing

    2010-12-01

    With the development of mechatronics technology and fault diagnosis theory, people regard flow information much more than before. Cheap, fast and accurate flow sensors are urgently needed by hydraulic industry. So MEMS sensor, which is small, low cost, well performed and easy to integrate, will surely play an important role in this field. Based on the new method of flow measurement which was put forward by our research group, this paper completed the measurement of flow rate in hydraulic system by setting up the mathematical model, using numerical simulation method and doing physical experiment. Based on viscous fluid flow equations we deduced differential pressure-velocity model of this new sensor and did optimization on parameters. Then, we designed and manufactured the throttle and studied the velocity and pressure field inside the sensor by FLUENT. Also in simulation we get the differential pressure-velocity curve .The model machine was simulated too to direct experiment. In the static experiments we calibrated the MEMS sensing element and built some sample sensors. Then in a hydraulic testing system we compared the sensor signal with a turbine meter. It presented good linearity and could meet general hydraulic system use. Based on the CFD curves, we analyzed the error reasons and made some suggestion to improve. In the dynamic test, we confirmed this sensor can realize high frequency flow detection by a 7 piston-pump.

  3. Gaining the necessary geologic, hydrologic, and geochemical understanding for additional brackish groundwater development, coastal San Diego, California, USA

    USGS Publications Warehouse

    Danskin, Wesley R.

    2012-01-01

    Local water agencies and the United States Geological Survey are using a combination of techniques to better understand the scant freshwater resources and the much more abundant brackish resources in coastal San Diego, California, USA. Techniques include installation of multiple-depth monitoring well sites; geologic and paleontological analysis of drill cuttings; geophysical logging to identify formations and possible seawater intrusion; sampling of pore-water obtained from cores; analysis of chemical constituents including trace elements and isotopes; and use of scoping models including a three-dimensional geologic framework model, rainfall-runoff model, regional groundwater flow model, and coastal density-dependent groundwater flow model. Results show that most fresh groundwater was recharged during the last glacial period and that the coastal aquifer has had recurring intrusions of fresh and saline water. These intrusions disguise the source, flowpaths, and history of ground water near the coast. The flow system includes a freshwater lens resting on brackish water; a 100-meter-thick flowtube of freshwater discharging under brackish estuarine water and above highly saline water; and broad areas of fine-grained coastal sediment filled with fairly uniform brackish water. Stable isotopes of hydrogen and oxygen indicate the recharged water flows through many kilometers of fractured crystalline rock before entering the narrow coastal aquifer.

  4. Thermography of the New River Inlet plume and nearshore currents

    NASA Astrophysics Data System (ADS)

    Chickadel, C.; Jessup, A.

    2012-12-01

    As part of the DARLA and RIVET experiments, thermal imaging systems mounted on a tower and in an airplane captured water flow in the New River Inlet, NC, USA. Kilometer-scale, airborne thermal imagery of the inlet details the ebb flow of the estuarine plume water mixing with ocean water. Multiple fronts, corresponding to the preferred channels through the ebb tidal delta, are imaged in the aerial data. A series of internal fronts suggest discreet sources of the tidal plume that vary with time. Focused thermal measurements made from a tower on the south side of the inlet viewed an area within a radius of a few hundred meters. Sub-meter resolution video from the tower revealed fine-scale flow features and the interaction of tidal exchange and wave-forced surfzone currents. Using the tower and airborne thermal image data we plan to provide geophysical information to compare with numerical models and in situ measurements made by other investigators. From the overflights, we will map the spatial and temporal extent of the estuarine plume to correlate with tidal phase and local wind conditions. From the tower data, we will investigate the structure of the nearshore flow using a thermal particle image velocimetry (PIV) technique, which is based on tracking motion of the surface temperature patterns. Long term variability of the mean and turbulent two-dimensional PIV currents will be correlated to local wave, tidal, and wind forcing parameters.

  5. Blood flow measurement using digital subtraction angiography for assessing hemodialysis access function

    NASA Astrophysics Data System (ADS)

    Koirala, Nischal; Setser, Randolph M.; Bullen, Jennifer; McLennan, Gordon

    2017-03-01

    Blood flow rate is a critical parameter for diagnosing dialysis access function during fistulography where a flow rate of 600 ml/min in arteriovenous graft or 400-500 ml/min in arteriovenous fistula is considered the clinical threshold for fully functioning access. In this study, a flow rate computational model for calculating intra-access flow to evaluate dialysis access patency was developed and validated in an in vitro set up using digital subtraction angiography. Flow rates were computed by tracking the bolus through two regions of interest using cross correlation (XCOR) and mean arrival time (MAT) algorithms, and correlated versus an in-line transonic flow meter measurement. The mean difference (mean +/- standard deviation) between XCOR and in-line flow measurements for in vitro setup at 3, 6, 7.5 and 10 frames/s was 118+/-63 37+/-59 31+/-31 and 46+/-57 ml/min respectively while for MAT method it was 86+/-56 57+/-72 35+/-85 and 19+/-129 ml/min respectively. The result of this investigation will be helpful for selecting candidate algorithms while blood flow computational tool is developed for clinical application.

  6. Sea Salt Aerosol, Atmospheric Radon and Meteorological Observations in the Western South Atlantic Ocean (February 1981).

    DTIC Science & Technology

    1983-09-28

    approximately isokinetic sampling conditions. The blower motor for the hi-vol was separated from the filter holder unit by a one- meter length of flexible...bridge bulkhead about 15 m above sea level and within 3 meters of the ARCAS inlet. The flow rate through the 20 cm x 25 cm glass fiber filters was...materials, atmospheric pressure, soil moisture and vegetative cover (Larson and Bressan, 1980). Radon concentrations measured a few meters above

  7. Validation of a 3D computational fluid-structure interaction model simulating flow through an elastic aperture.

    PubMed

    Quaini, A; Canic, S; Glowinski, R; Igo, S; Hartley, C J; Zoghbi, W; Little, S

    2012-01-10

    This work presents a validation of a fluid-structure interaction computational model simulating the flow conditions in an in vitro mock heart chamber modeling mitral valve regurgitation during the ejection phase during which the trans-valvular pressure drop and valve displacement are not as large. The mock heart chamber was developed to study the use of 2D and 3D color Doppler techniques in imaging the clinically relevant complex intra-cardiac flow events associated with mitral regurgitation. Computational models are expected to play an important role in supporting, refining, and reinforcing the emerging 3D echocardiographic applications. We have developed a 3D computational fluid-structure interaction algorithm based on a semi-implicit, monolithic method, combined with an arbitrary Lagrangian-Eulerian approach to capture the fluid domain motion. The mock regurgitant mitral valve corresponding to an elastic plate with a geometric orifice, was modeled using 3D elasticity, while the blood flow was modeled using the 3D Navier-Stokes equations for an incompressible, viscous fluid. The two are coupled via the kinematic and dynamic conditions describing the two-way coupling. The pressure, the flow rate, and orifice plate displacement were measured and compared with numerical simulation results. In-line flow meter was used to measure the flow, pressure transducers were used to measure the pressure, and a Doppler method developed by one of the authors was used to measure the axial displacement of the orifice plate. The maximum recorded difference between experiment and numerical simulation for the flow rate was 4%, the pressure 3.6%, and for the orifice displacement 15%, showing excellent agreement between the two. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. 40 CFR 86.116-94 - Calibrations, frequency and overview.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... positive displacement pump or Critical Flow Venturi shall be calibrated following initial installation... an organic gas retention and calibration on the evaporative emissions enclosure (see § 86.117-90(c)). (4) Calibrate the gas meters or flow instrumentation used for providing total flow measurement for...

  9. New insight into lunar impact melt mobility from the LRO camera

    USGS Publications Warehouse

    Bray, Veronica J.; Tornabene, Livio L.; Keszthelyi, Laszlo P.; McEwen, Alfred S.; Hawke, B. Ray; Giguere, Thomas A.; Kattenhorn, Simon A.; Garry, William B.; Rizk, Bashar; Caudill, C.M.; Gaddis, Lisa R.; van der Bogert, Carolyn H.

    2010-01-01

    The Lunar Reconnaissance Orbiter Camera (LROC) is systematically imaging impact melt deposits in and around lunar craters at meter and sub-meter scales. These images reveal that lunar impact melts, although morphologically similar to terrestrial lava flows of similar size, exhibit distinctive features (e.g., erosional channels). Although generated in a single rapid event, the post-impact mobility and morphology of lunar impact melts is surprisingly complex. We present evidence for multi-stage influx of impact melt into flow lobes and crater floor ponds. Our volume and cooling time estimates for the post-emplacement melt movements noted in LROC images suggest that new flows can emerge from melt ponds an extended time period after the impact event.

  10. A Field Exercise on Groundwater Flow Using Seepage Meters and Mini-Piezometers.

    ERIC Educational Resources Information Center

    Lee, David R.; Cherry, John A.

    1979-01-01

    Basic principles of physical hydrogeology and the nature of hydrologic interactions between groundwater and surface water can be demonstrated using two devices, the miniature piezometer and the seepage meter which can be cheaply constructed by the teacher and students. Use of the devices and learning activities are presented. (RE)

  11. A seepage meter designed for use in flowing water

    USGS Publications Warehouse

    Rosenberry, D.O.

    2008-01-01

    Seepage meters provide one of the most direct means to measure exchange of water across the sediment-water interface, but they generally have been unsuitable for use in fluvial settings. Although the seepage bag can be placed inside a rigid container to minimize velocity head concerns, the seepage cylinder installed in the sediment bed projects into and disrupts the flow field, altering both the local-scale fluid exchange as well as measurement of that exchange. A low-profile seepage meter designed for use in moving water was tested in a seepage meter flux tank where both current velocity and seepage velocity could be controlled. The conical seepage cylinder protrudes only slightly above the sediment bed and is connected via tubing to a seepage bag or flowmeter positioned inside a rigid shelter that is located nearby where current velocity is much slower. Laboratory and field tests indicate that the net effect of the small protrusion of the seepage cylinder into the surface water flow field is inconsequentially small for surface water currents up to 65 cm s-1. Current velocity affects the variability of seepage measurements; seepage standard deviation increased from ???2 to ???6 cm d-1 as current velocity increased from 9 to 65 cm s-1. Substantial bias can result if the shelter is not placed to minimize hydraulic gradient between the bag and the seepage cylinder.

  12. Geohydrologic and drill-hole data for test well USW H-4, Yucca Mountain, Nye County, Nevada

    USGS Publications Warehouse

    Whitfield, M.S.; Thordarson, William; Eshom, E.P.

    1984-01-01

    Data are presented on drilling operations, lithology, geophysical well logs, sidewall-core samples, water-level monitoring, pumping tests, injection tests, radioactive-tracer borehole flow survey, and water chemistry for test well USW H-4. The well is one of a series of test wells drilled in the southwestern part of the Nevada Test Site, Nye County, Nevada, in cooperation with the U.S. Department of Energy. These test wells are part of the Nevada Nuclear Waste Storage Investigations to identify sites for storage of high-level radioactive wastes. Test well USW H-4 was drilled in ash-flow tuff to a total depth of 1,219 meters. Depth to water below land surface was 519 meters or at an altitude of 730 meters above sea level. After test pumping at a rate of 17.4 liters per second for approximately 9 days, the drawdown was 4.85 meters. A radioactive borehole-flow survey indicated that the Bullfrog Member was the most productive geologic unit, producing 36.5 percent of the water in the well. The second most productive geologic unit was the Tram Member, which produced 32 percent of the water. The water in test well USW H-4 is predominantly a soft, sodium bicarbonate type of water typical of water produced in tuffaceous rocks in southern Nevada. (USGS)

  13. Long-term temperature monitoring at the biological community site on the Nankai accretionary prism off Kii Peninsula

    NASA Astrophysics Data System (ADS)

    Goto, S.; Hamamoto, H.; Yamano, M.; Kinoshita, M.; Ashi, J.

    2008-12-01

    Nankai subduction zone off Kii Peninsula is one of the most intensively surveyed areas for studies on the seismogenic zone. Multichannel seismic reflection surveys carried out in this area revealed the existence of splay faults that branched from the subduction zone plate boundary [Park et al., 2002]. Along the splay faults, reversal of reflection polarity was observed, indicating elevated pore fluid pressure along the faults. Cold seepages with biological communities were discovered along a seafloor outcrop of one of the splay faults through submersible observations. Long-term temperature monitoring at a biological community site along the outcrop revealed high heat flow carried by upward fluid flow (>180 mW/m2) [Goto et al., 2003]. Toki et al. [2004] estimated upward fluid flow rates of 40-200 cm/yr from chloride distribution of interstitial water extracted from sediments in and around biological community sites along the outcrop. These observation results suggest upward fluid flow along the splay fault. In order to investigate hydrological nature of the splay fault, we conducted long-term temperature monitoring again in the same cold seepage site where Goto et al. [2003] carried out long-term temperature monitoring. In this presentation, we present results of the temperature monitoring and estimate heat flow carried by upward fluid flow from the temperature records. In this long-term temperature monitoring, we used stand-alone heat flow meter (SAHF), a probe-type sediment temperature recorder. Two SAHFs (SAHF-3 and SAHF-4) were used in this study. SAHF-4 was inserted into a bacterial mat, within several meters of which the previous long-term temperature monitoring was conducted. SAHF-3 was penetrated into ordinary sediment near the bacterial mat. The sub-bottom temperature records were obtained for 8 months. The subsurface temperatures oscillated reflecting bottom- water temperature variation (BTV). For sub-bottom temperatures measured with SAHF-3 (outside of the bacterial mat), we found that the effects of the BTV propagated into sediment by conduction only. By correcting the effect of the BTV, conductive heat flow estimated is higher than 100 mW/m2. Sub-bottom temperatures measured within bacterial mat (SAHF-4) except for the topmost sensor could be explained by a conduction model. The heat flow estimated based on the conduction model is similar to that measured with SAHF-3. The temperature of the topmost sensor is slightly higher than that expected from the conduction model. To explain the high temperature, upward fluid flow at a rate of 10-7 m/s order is needed. Heat flow carried by the upward fluid flow is higher than that estimated by Goto et al. [2003]. Heat flow value expected from the distribution of heat flow around this area is 70-80 mW/m2. The high heat flow values inside and outside the bacterial mat estimated in the present and previous studies may reflect upward fluid flow along the splay fault.

  14. 40 CFR 1065.225 - Intake-air flow meter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... concentrations, if the same signal is used in a chemical-balance calculation to determine work from brake... tube, or a hot-wire anemometer. Note that your overall system for measuring intake-air flow must meet...

  15. 25. CURRENT METERS: GURLEY MODEL NO. 665 AT CENTER, GURLEY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. CURRENT METERS: GURLEY MODEL NO. 665 AT CENTER, GURLEY MODEL NO. 625 'PYGMY' CURRENT METER AT LEFT, AND WES MINIATURE PRICE-TYPE CURRENT METER AT RIGHT. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  16. 40 CFR 98.154 - Monitoring and QA/QC requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the concentrations of the process samples. (b) The mass flow of the product stream containing the HFC... concentration and volumetric flow rate determined by measurement of volumetric flow rate using EPA Method 2, 2A... volumetric flow rate at the inlet or by a metering device for HFC-23 sent to the device. Determine a new...

  17. Laboratory evaluation of an OTT acoustic digital current meter and a SonTek Laboratory acoustic Doppler velocimeter

    USGS Publications Warehouse

    Vermeyen, T.B.; Oberg, Kevin A.; Jackson, Patrick Ryan

    2009-01-01

    Recently, an acoustic current meter known as the OTT * acoustic digital current meter (ADC) was introduced as an alternative instrument for stream gaging measurements. The Bureau of Reclamation and the U.S. Geological Survey collaborated on a side- by-side evaluation of the ADC and a SonTek/YSI acoustic Doppler velocimeter (ADV). Measurements were carried out in a laboratory flume to evaluate the performance characteristics of the ADC under a range of flow and boundary conditions. The flume contained a physical model of a mountain river with a diversion dam and variety of bed materials ranging from smooth mortar to a cobble bed. The instruments were installed on a trolley system that allowed them to be easily moved within the flume while maintaining a consistent probe orientation. More than 50 comparison measurements were made in an effort to verify the manufacturer’s performance specifications and to evaluate potential boundary disturbance for near-bed and vertical boundary measurements. Data and results from this evaluation are presented and discussed. 

  18. Peak flow meter with a questionnaire and mini-spirometer to help detect asthma and COPD in real-life clinical practice: a cross-sectional study.

    PubMed

    Thorat, Yogesh T; Salvi, Sundeep S; Kodgule, Rahul R

    2017-05-09

    Peak flow meter with questionnaire and mini-spirometer are considered as alternative tools to spirometry for screening of asthma and chronic obstructive pulmonary disease. However, the accuracy of these tools together, in clinical settings for disease diagnosis, has not been studied. Two hundred consecutive patients with respiratory complaints answered a short symptom questionnaire and performed peak expiratory flow measurements, standard spirometry with Koko spirometer and mini-spirometry (COPD-6). Spirometry was repeated after bronchodilation. Physician made a final diagnosis of asthma, chronic obstructive pulmonary disease and others. One eighty nine patients (78 females) with age 51 ± 17 years with asthma (115), chronic obstructive pulmonary disease (33) and others (41) completed the study. "Breathlessness > 6months" and "cough > 6months" were important symptoms to detect obstructive airways disease. "Asymptomatic period > 2 weeks" had the best sensitivity (Sn) and specificity (Sp) to differentiate asthma and chronic obstructive pulmonary disease. A peak expiratory flow of < 80% predicted was the best cut-off to detect airflow limitation (Sn 90%, Sp 50%). Respiratory symptoms with PEF < 80% predicted, had Sn 84 and Sp 93% to detect OAD. COPD-6 device under-estimated FEV 1 by 13 mL (95% CI: -212, 185). At a cut-off of 0.75, the FEV 1 /FEV 6 had the best accuracy (Sn 80%, Sp 86%) to detect airflow limitation. Peak flow meter with few symptom questions can be effectively used in clinical practice for objective detection of asthma and chronic obstructive pulmonary disease, in the absence of good quality spirometry. Mini-spirometers are useful in detection of obstructive airways diseases but FEV 1 measured is inaccurate. DIFFERENTIATING CONDITIONS IN POORLY-EQUIPPED SETTINGS: A simple questionnaire and peak flow meter measurements can help doctors differentiate between asthma and chronic lung disease. In clinical settings where access to specialist equipment and knowledge is limited, it can be challenging for doctors to tell the difference between asthma and chronic obstructive pulmonary disease (COPD). To determine a viable alternative method for differentiating between these diseases, Rahul Kodgule and colleagues at the Chest Research Foundation in Pune, India, trialed a simplified version of two existing symptom questionnaires, combined with peak flow meter measurements. They assessed 189 patients using this method, and found it aided diagnosis with high sensitivity and specificity. Breathlessness, cough and wheeze were the minimal symptoms required for COPD diagnosis, while the length of asymptomatic periods was most helpful in distinguishing asthma from COPD.

  19. The need to consider temporal variability when modelling exchange at the sediment-water interface

    USGS Publications Warehouse

    Rosenberry, Donald O.

    2011-01-01

    Most conceptual or numerical models of flows and processes at the sediment-water interface assume steady-state conditions and do not consider temporal variability. The steady-state assumption is required because temporal variability, if quantified at all, is usually determined on a seasonal or inter-annual scale. In order to design models that can incorporate finer-scale temporal resolution we first need to measure variability at a finer scale. Automated seepage meters that can measure flow across the sediment-water interface with temporal resolution of seconds to minutes were used in a variety of settings to characterize seepage response to rainfall, wind, and evapotranspiration. Results indicate that instantaneous seepage fluxes can be much larger than values commonly reported in the literature, although seepage does not always respond to hydrological processes. Additional study is needed to understand the reasons for the wide range and types of responses to these hydrologic and atmospheric events.

  20. Orifice Mass Flow Calculation in NASA's W-8 Single Stage Axial Compressor Facility

    NASA Technical Reports Server (NTRS)

    Bozak, Richard F.

    2018-01-01

    Updates to the orifice mass flow calculation for the W-8 Single Stage Axial Compressor Facility at NASA Glenn Research Center are provided to include the effect of humidity and incorporate ISO 5167. A methodology for including the effect of humidity into the inlet orifice mass flow calculation is provided. Orifice mass flow calculations provided by ASME PTC-19.5-2004, ASME MFC-3M-2004, ASME Fluid Meters, and ISO 5167 are compared for W-8's atmospheric inlet orifice plate. Differences in expansion factor and discharge coefficient given by these standards give a variation of about +/- 75% mass flow except for a few cases. A comparison of the calculations with an inlet static pressure mass flow correlation and a fan exit mass flow integration using test data from a 2017 turbofan rotor test in W-8 show good agreement between the inlet static pressure mass flow correlation, ISO 5167, and ASME Fluid Meters. While W-8's atmospheric inlet orifice plate violates the pipe diameter limit defined by each of the standards, the ISO 5167 is chosen to be the primary orifice mass flow calculation to use in the W-8 facility.

  1. Centrifugal multiplexing fixed-volume dispenser on a plastic lab-on-a-disk for parallel biochemical single-end-point assays

    PubMed Central

    La, Moonwoo; Park, Sang Min; Kim, Dong Sung

    2015-01-01

    In this study, a multiple sample dispenser for precisely metered fixed volumes was successfully designed, fabricated, and fully characterized on a plastic centrifugal lab-on-a-disk (LOD) for parallel biochemical single-end-point assays. The dispenser, namely, a centrifugal multiplexing fixed-volume dispenser (C-MUFID) was designed with microfluidic structures based on the theoretical modeling about a centrifugal circumferential filling flow. The designed LODs were fabricated with a polystyrene substrate through micromachining and they were thermally bonded with a flat substrate. Furthermore, six parallel metering and dispensing assays were conducted at the same fixed-volume (1.27 μl) with a relative variation of ±0.02 μl. Moreover, the samples were metered and dispensed at different sub-volumes. To visualize the metering and dispensing performances, the C-MUFID was integrated with a serpentine micromixer during parallel centrifugal mixing tests. Parallel biochemical single-end-point assays were successfully conducted on the developed LOD using a standard serum with albumin, glucose, and total protein reagents. The developed LOD could be widely applied to various biochemical single-end-point assays which require different volume ratios of the sample and reagent by controlling the design of the C-MUFID. The proposed LOD is feasible for point-of-care diagnostics because of its mass-producible structures, reliable metering/dispensing performance, and parallel biochemical single-end-point assays, which can identify numerous biochemical. PMID:25610516

  2. Predictions of hydrothermal alteration within near-ridge oceanic crust from coordinated geochemical and fluid flow models

    USGS Publications Warehouse

    Wetzel, L.R.; Raffensperger, Jeff P.; Shock, E.L.

    2001-01-01

    Coordinated geochemical and hydrological calculations guide our understanding of the composition, fluid flow patterns, and thermal structure of near-ridge oceanic crust. The case study presented here illustrates geochemical and thermal changes taking place as oceanic crust ages from 0.2 to 1.0 Myr. Using a finite element code, we model fluid flow and heat transport through the upper few hundred meters of an abyssal hill created at an intermediate spreading rate. We use a reaction path model with a customized database to calculate equilibrium fluid compositions and mineral assemblages of basalt and seawater at 500 bars and temperatures ranging from 150 to 400??C. In one scenario, reaction path calculations suggest that volume increases on the order of 10% may occur within portions of the basaltic basement. If this change in volume occurred, it would be sufficient to fill all primary porosity in some locations, effectively sealing off portions of the oceanic crust. Thermal profiles resulting from fluid flow simulations indicate that volume changes along this possible reaction path occur primarily within the first 0.4 Myr of crustal aging. ?? 2001 Elsevier Science B.V. All rights reserved.

  3. Elbow mass flow meter

    DOEpatents

    McFarland, A.R.; Rodgers, J.C.; Ortiz, C.A.; Nelson, D.C.

    1994-08-16

    The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity. 3 figs.

  4. 78 FR 13905 - Government-Owned Inventions, Available for Licensing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-01

    ... to the National Aeronautics and Space Administration, have been filed in the United States Patent and... Including Crack Arresting Barrier; NASA Case No.: MFS 32761-1-CIP: Eddy Current Minimizing Flow Plug for Use in Flow Conditioning and Flow Metering. Sumara M. Thompson-King, Deputy General Counsel. [FR Doc...

  5. Production facility layout by comparing moment displacement using BLOCPLAN and ALDEP Algorithms

    NASA Astrophysics Data System (ADS)

    Tambunan, M.; Ginting, E.; Sari, R. M.

    2018-02-01

    Production floor layout settings include the organizing of machinery, materials, and all the equipments used in the production process in the available area. PT. XYZ is a company that manufactures rubber and rubber compounds for retreading tire threaded with hot and cold cooking system. In the production of PT. XYZ is divided into three interrelated parts, namely Masterbatch Department, Department Compound, and Procured Thread Line Department. PT. XYZ has a production process with material flow is irregular and the arrangement of machine is complicated and need to be redesigned. The purpose of this study is comparing movement displacement using BLOCPLAN and ALDEP algorithm in order to redesign existing layout. Redesigning the layout of the production floor is done by applying algorithms of BLOCPLAN and ALDEP. The algorithm used to find the best layout design by comparing the moment displacement and the flow pattern. Moment displacement on the floor layout of the company’s production currently amounts to 2,090,578.5 meters per year and material flow pattern is irregular. Based on the calculation, the moment displacement for the BLOCPLAN is 1,551,344.82 meter per year and ALDEP is 1,600,179 meter per year. Flow Material resulted is in the form of straight the line.

  6. Helicopter electromagnetic survey of the Model Land Area, Southeastern Miami-Dade County, Florida

    USGS Publications Warehouse

    Fitterman, David V.; Deszcz-Pan, Maria; Prinos, Scott T.

    2012-01-01

    This report describes a helicopter electromagnetic survey flown over the Model Land Area in southeastern Miami-Dade County, Florida, to map saltwater intrusion in the Biscayne aquifer. The survey, which is located south and east of Florida City, Florida, covers an area of 115 square kilometers with a flight-line spacing of 400 meters. A five-frequency, horizontal, coplanar bird with frequencies ranging from 400 to 100,000 Hertz was used. The data were interpreted using differential resistivity analysis and inversion to produce cross sections and resistivity depth-slice maps. The depth of investigation is as deep as 100 meters in freshwater-saturated portions of the Biscayne aquifer and the depth diminishes to about 50 meters in areas that are intruded by saltwater. The results compare favorably with ground-based, time-domain electromagnetic soundings and induction logs from observation wells in the area. The base of a high-resistivity, freshwater-saturated zone mapped in the northern 2 kilometers of the survey area corresponds quite well with the base of the surficial aquifer that has been determined by drilling. In general, saltwater in the survey area extends 9 to 12 kilometers inland from the coast; however, there is a long nose of saltwater centered along the Card Sound Road Canal that extends 15 kilometers inland. The cause of this preferential intrusion is likely due to uncontrolled surface flow along the canal and subsequent leakage of saltwater into the aquifer. Saltwater also extends farther inland in the area between U.S. Highway 1 and Card Sound Road than it does to the west of this area. Until 1944, a railroad grade occupied the current location of U.S. Highway 1. Borrow ditches associated with the railroad grade connected to Barnes Sound and allowed saltwater to flow during droughts and storm surges to within a few kilometers of Florida City. Relicts of this saltwater that settled to the bottom of the Biscayne aquifer can be seen in the helicopter electromagnetic data. The area to the west of U.S. Highway 1 is more resistive in the upper 10 meters than the area to the east of the road; this reflects the influence of surface-water flows that are blocked by U.S. Highway 1. Between Card Sound Road and U.S. Highway 1, resistivities are slightly lower compared to adjacent areas. In the southern portion of the survey area, the surficial aquifer underlying the Biscayne aquifer is more resistive; this indicates that it contains fresher water than that found at the base of the Biscayne aquifer.

  7. Six-Phase Heating(trademark) Pilot-Scale Test. Technology Performance Report, Dense Non-Aqueous Phase Liquid, Eastern Parking Lot Groundwater Plume. Air Force Plant 4, Fort Worth, Texas

    DTIC Science & Technology

    2001-05-01

    The well vapor flows were calculated using the following formula taken from the Dwyer Series DS-300 Flow Sensor Instal/ation and Operating...IVllllble. TNRCC-D199 (Rev. 09-01 93) Send oriainal CODV by cerllfled mall 10: / TDLA ).(WWD/PIPl, P.O. BOll 12157 Austin TX 7871 1 Please use black Ink...gas, impinger exhaust, dry gas meter inlet, and dry gas meter outlet. A Fyrite™ kit was used to measure the oxygen and carbon dioxide concentration in

  8. Absorption coefficients for water vapor at 193 nm from 300 to 1073 K

    NASA Technical Reports Server (NTRS)

    Kessler, W. J.; Carleton, K. L.; Marinelli, W. J.

    1993-01-01

    Measurements of the water absorption coefficient at 193 nm from 300 to 1073 K are reported. The measurements were made using broadband VUV radiation and a monochromator-based detection system. The water vapor was generated by a saturator and metered into a flowing, 99 cm absorption cell via a water vapor mass flow meter. The 193 nm absorption coefficient measurements are compared to room temperature and high temperature shock tube measurements with good agreement. The absorption can be parameterized by a nu3 vibrational mode reaction coordinate and the thermal population of the nu3 mode.

  9. Skin-friction measurements by laser interferometry

    NASA Technical Reports Server (NTRS)

    Kim, K.-S.; Settles, G. S.

    1989-01-01

    The measurement of skin friction in rapidly distorted compressible flows is difficult, and very few reliable techniques are available. A recent development, the laser interferometer skin friction (LISF) meter, promises to be useful for this purpose. This technique interferometrically measures the time rate of thinning of an oil film applied to an aerodynamic surface. Under the proper conditions the wall shear stress may thus be found directly, without reference to flow properties. The applicability of the LISF meter to supersonic boundary layers is examined experimentally. Its accuracy and repeatability are assessed, and conditions required for its successful application are considered.

  10. Probe Measures Fouling As In Heat Exchangers

    NASA Technical Reports Server (NTRS)

    Marner, Wilbur J.; Macdavid, Kenton S.

    1990-01-01

    Combustion deposits reduce transfer of heat. Instrument measures fouling like that on gas side of heat exchanger in direct-fired boiler or heat-recovery system. Heat-flux probe includes tube with embedded meter in outer shell. Combustion gases flow over probe, and fouling accumulates on it, just as fouling would on heat exchanger. Embedded heat-flow meter is sandwich structure in which thin Chromel layers and middle alloy form thermopile. Users determine when fouling approaches unacceptable levels so they schedule cleaning and avoid decreased transfer of heat and increased drop in pressure fouling causes. Avoids cost of premature, unnecessary maintenance.

  11. Bacterial Community Analysis of Drinking Water Biofilms in Southern Sweden

    PubMed Central

    Lührig, Katharina; Canbäck, Björn; Paul, Catherine J.; Johansson, Tomas; Persson, Kenneth M.; Rådström, Peter

    2015-01-01

    Next-generation sequencing of the V1–V2 and V3 variable regions of the 16S rRNA gene generated a total of 674,116 reads that described six distinct bacterial biofilm communities from both water meters and pipes. A high degree of reproducibility was demonstrated for the experimental and analytical work-flow by analyzing the communities present in parallel water meters, the rare occurrence of biological replicates within a working drinking water distribution system. The communities observed in water meters from households that did not complain about their drinking water were defined by sequences representing Proteobacteria (82–87%), with 22–40% of all sequences being classified as Sphingomonadaceae. However, a water meter biofilm community from a household with consumer reports of red water and flowing water containing elevated levels of iron and manganese had fewer sequences representing Proteobacteria (44%); only 0.6% of all sequences were classified as Sphingomonadaceae; and, in contrast to the other water meter communities, markedly more sequences represented Nitrospira and Pedomicrobium. The biofilm communities in pipes were distinct from those in water meters, and contained sequences that were identified as Mycobacterium, Nocardia, Desulfovibrio, and Sulfuricurvum. The approach employed in the present study resolved the bacterial diversity present in these biofilm communities as well as the differences that occurred in biofilms within a single distribution system, and suggests that next-generation sequencing of 16S rRNA amplicons can show changes in bacterial biofilm communities associated with different water qualities. PMID:25739379

  12. Bacterial community analysis of drinking water biofilms in southern Sweden.

    PubMed

    Lührig, Katharina; Canbäck, Björn; Paul, Catherine J; Johansson, Tomas; Persson, Kenneth M; Rådström, Peter

    2015-01-01

    Next-generation sequencing of the V1-V2 and V3 variable regions of the 16S rRNA gene generated a total of 674,116 reads that described six distinct bacterial biofilm communities from both water meters and pipes. A high degree of reproducibility was demonstrated for the experimental and analytical work-flow by analyzing the communities present in parallel water meters, the rare occurrence of biological replicates within a working drinking water distribution system. The communities observed in water meters from households that did not complain about their drinking water were defined by sequences representing Proteobacteria (82-87%), with 22-40% of all sequences being classified as Sphingomonadaceae. However, a water meter biofilm community from a household with consumer reports of red water and flowing water containing elevated levels of iron and manganese had fewer sequences representing Proteobacteria (44%); only 0.6% of all sequences were classified as Sphingomonadaceae; and, in contrast to the other water meter communities, markedly more sequences represented Nitrospira and Pedomicrobium. The biofilm communities in pipes were distinct from those in water meters, and contained sequences that were identified as Mycobacterium, Nocardia, Desulfovibrio, and Sulfuricurvum. The approach employed in the present study resolved the bacterial diversity present in these biofilm communities as well as the differences that occurred in biofilms within a single distribution system, and suggests that next-generation sequencing of 16S rRNA amplicons can show changes in bacterial biofilm communities associated with different water qualities.

  13. Image based automatic water meter reader

    NASA Astrophysics Data System (ADS)

    Jawas, N.; Indrianto

    2018-01-01

    Water meter is used as a tool to calculate water consumption. This tool works by utilizing water flow and shows the calculation result with mechanical digit counter. Practically, in everyday use, an operator will manually check the digit counter periodically. The Operator makes logs of the number shows by water meter to know the water consumption. This manual operation is time consuming and prone to human error. Therefore, in this paper we propose an automatic water meter digit reader from digital image. The digits sequence is detected by utilizing contour information of the water meter front panel.. Then an OCR method is used to get the each digit character. The digit sequence detection is an important part of overall process. It determines the success of overall system. The result shows promising results especially in sequence detection.

  14. Modeling lahar behavior and hazards

    USGS Publications Warehouse

    Manville, Vernon; Major, Jon J.; Fagents, Sarah A.

    2013-01-01

    Lahars are highly mobile mixtures of water and sediment of volcanic origin that are capable of traveling tens to > 100 km at speeds exceeding tens of km hr-1. Such flows are among the most serious ground-based hazards at many volcanoes because of their sudden onset, rapid advance rates, long runout distances, high energy, ability to transport large volumes of material, and tendency to flow along existing river channels where populations and infrastructure are commonly concentrated. They can grow in volume and peak discharge through erosion and incorporation of external sediment and/or water, inundate broad areas, and leave deposits many meters thick. Furthermore, lahars can recur for many years to decades after an initial volcanic eruption, as fresh pyroclastic material is eroded and redeposited during rainfall events, resulting in a spatially and temporally evolving hazard. Improving understanding of the behavior of these complex, gravitationally driven, multi-phase flows is key to mitigating the threat to communities at lahar-prone volcanoes. However, their complexity and evolving nature pose significant challenges to developing the models of flow behavior required for delineating their hazards and hazard zones.

  15. DEVELOPMENT OF A LOW-COST INFERENTIAL NATURAL GAS ENERGY FLOW RATE PROTOTYPE RETROFIT MODULE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    E. Kelner; T.E. Owen; D.L. George

    2004-03-01

    In 1998, Southwest Research Institute{reg_sign} began a multi-year project co-funded by the Gas Research Institute (GRI) and the U.S. Department of Energy. The project goal is to develop a working prototype instrument module for natural gas energy measurement. The module will be used to retrofit a natural gas custody transfer flow meter for energy measurement, at a cost an order of magnitude lower than a gas chromatograph. Development and evaluation of the prototype retrofit natural gas energy flow meter in 2000-2001 included: (1) evaluation of the inferential gas energy analysis algorithm using supplemental gas databases and anticipated worst-case gas mixtures;more » (2) identification and feasibility review of potential sensing technologies for nitrogen diluent content; (3) experimental performance evaluation of infrared absorption sensors for carbon dioxide diluent content; and (4) procurement of a custom ultrasonic transducer and redesign of the ultrasonic pulse reflection correlation sensor for precision speed-of-sound measurements. A prototype energy meter module containing improved carbon dioxide and speed-of-sound sensors was constructed and tested in the GRI Metering Research Facility at SwRI. Performance of this module using transmission-quality natural gas and gas containing supplemental carbon dioxide up to 9 mol% resulted in gas energy determinations well within the inferential algorithm worst-case tolerance of {+-}2.4 Btu/scf (nitrogen diluent gas measured by gas chromatograph). A two-week field test was performed at a gas-fired power plant to evaluate the inferential algorithm and the data acquisition requirements needed to adapt the prototype energy meter module to practical field site conditions.« less

  16. Towards metering tap water by Lorentz force velocimetry

    NASA Astrophysics Data System (ADS)

    Vasilyan, Suren; Ebert, Reschad; Weidner, Markus; Rivero, Michel; Halbedel, Bernd; Resagk, Christian; Fröhlich, Thomas

    2015-11-01

    In this paper, we present enhanced flow rate measurement by applying the contactless Lorentz Force Velocimetry (LFV) technique. Particularly, we show that the LFV is a feasible technique for metering the flow rate of salt water in a rectangular channel. The measurements of the Lorentz forces as a function of the flow rate are presented for different electrical conductivities of the salt water. The smallest value of conductivity is achieved at 0.06 S·m-1, which corresponds to the typical value of tap water. In comparison with previous results, the performance of LFV is improved by approximately 2 orders of magnitude by means of a high-precision differential force measurement setup. Furthermore, the sensitivity curve and the calibration factor of the flowmeter are provided based on extensive measurements for the flow velocities ranging from 0.2 to 2.5 m·s-1 and conductivities ranging from 0.06 to 10 S·m-1.

  17. Emergency assessment of post-fire debris-flow hazards for the 2013 Rim Fire, Stanislaus National Forest and Yosemite National Park, California

    USGS Publications Warehouse

    Staley, Dennis M.

    2013-01-01

    Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can produce dangerous flash floods and debris flows. In this report, empirical models are used to predict the probability and magnitude of debris-flow occurrence in response to a 10-year rainstorm for the 2013 Rim fire in Yosemite National Park and the Stanislaus National Forest, California. Overall, the models predict a relatively high probability (60–80 percent) of debris flow for 28 of the 1,238 drainage basins in the burn area in response to a 10-year recurrence interval design storm. Predictions of debris-flow volume suggest that debris flows may entrain a significant volume of material, with 901 of the 1,238 basins identified as having potential debris-flow volumes greater than 10,000 cubic meters. These results of the relative combined hazard analysis suggest there is a moderate likelihood of significant debris-flow hazard within and downstream of the burn area for nearby populations, infrastructure, wildlife, and water resources. Given these findings, we recommend that residents, emergency managers, and public works departments pay close attention to weather forecasts and National-Weather-Service-issued Debris Flow and Flash Flood Outlooks, Watches and Warnings and that residents adhere to any evacuation orders.

  18. JPRS Report, Science and Technology: Europe Twenty-Fourth ISATA International Symposium on Automotive Technology and Automation.

    DTIC Science & Technology

    1991-09-05

    Traffic and Driving and Y Ishii, Oki Electric Industry, Japan " Mazda Car Communication System" Mazda Car Corporation , FRG IMPROVING TRAFFIC FLOW... Strategy to Reduce 151 Blocking-Back During Oversaturation using the Microsimulation Model Nemis" S Shepherd, Institute for Transport Studies, UK 910085...J Garber, C W Lynn and W S Ferguson, University of Virginia, USA 910087 "Ramp Metering Strategies for Motorways Incorporating Dynamic 177 Origin

  19. Development of Automatic Control of Bayer Plant Digestion

    NASA Astrophysics Data System (ADS)

    Riffaud, J. P.

    Supervisory computer control has been achieved in Alcan's Bayer Plants at Arvida, Quebec, Canada. The purpose of the automatic control system is to stabilize and consequently increase, the alumina/caustic ratio within the digester train and in the blow-off liquor. Measurements of the electrical conductivity of the liquor are obtained from electrodeless conductivity meters. These signals, along with several others are scanned by the computer and converted to engineering units, using specific relationships which are updated periodically for calibration purposes. On regular time intervals, values of ratio are compared to target values and adjustments are made to the bauxite flow entering the digesters. Dead time compensation included in the control algorithm enables a faster rate for corrections. Modification of production rate is achieved through careful timing of various flow changes. Calibration of the conductivity meters is achieved by sampling at intervals the liquor flowing through them, and analysing it with a thermometric titrator. Calibration of the thermometric titrator is done at intervals with a standard solution. Calculations for both calibrations are performed by computer from data entered by the analyst. The computer was used for on-line data collection, modelling of the digester system, calculation of disturbances and simulation of control strategies before implementing the most successful strategy in the Plant. Control of ratio has been improved by the integrated system, resulting in increased Plant productivity.

  20. Advanced Instrumentation for Molten Salt Flow Measurements at NEXT

    NASA Astrophysics Data System (ADS)

    Tuyishimire, Olive

    2017-09-01

    The Nuclear Energy eXperiment Testing (NEXT) Lab at Abilene Christian University is building a Molten Salt Loop to help advance the technology of molten salt reactors (MSR). NEXT Lab's aim is to be part of the solution for the world's top challenges by providing safe, clean, and inexpensive energy, clean water and medical Isotopes. Measuring the flow rate of the molten salt in the loop is essential to the operation of a MSR. Unfortunately, there is no flow meter that can operate in the high temperature and corrosive environment of a molten salt. The ultrasonic transit time method is proposed as one way to measure the flow rate of high temperature fluids. Ultrasonic flow meter uses transducers that send and receive acoustic waves and convert them into electrical signals. Initial work presented here focuses on the setup of ultrasonic transducers. This presentation is the characterization of the pipe-fluid system with water as a baseline for future work.

  1. Newly Discovered Ring-Moat Dome Structures in the Lunar Maria: Possible Origins and Implications

    NASA Astrophysics Data System (ADS)

    Zhang, Feng; Head, James W.; Basilevsky, Alexander T.; Bugiolacchi, Roberto; Komatsu, Goro; Wilson, Lionel; Fa, Wenzhe; Zhu, Meng-Hua

    2017-09-01

    We report on a newly discovered morphological feature on the lunar surface, here named Ring-Moat Dome Structure (RMDS). These low domes (a few meters to 20 m height with slopes <5°) are typically surrounded by narrow annular depressions or moats. We mapped about 2,600 RMDSs in the lunar maria with diameters ranging from tens to hundreds of meters. Four candidate hypotheses for their origin involving volcanism are considered. We currently favor a mechanism for the formation of the RMDS related to modification of the initial lava flows through inflated flow squeeze-ups and/or extrusion of magmatic foams below a cooling lava flow surface. These newly discovered features provide new insights into the nature of emplacement of lunar lava flows, suggesting that in the waning stages of a dike emplacement event, magmatic foams can be produced, extrude to the surface as the dike closes, and break through the upper lava flow thermal boundary layer (crust) to form foam mounds and surrounding moats.

  2. Safety and diagnostic systems on the Liquid Lithium Test Stand (LLTS)

    NASA Astrophysics Data System (ADS)

    Schwartz, J. A.; Jaworski, M. A.; Ellis, R.; Kaita, R.; Mozulay, R.

    2013-10-01

    The Liquid Lithium Test Stand (LLTS) is a test bed for development of flowing liquid lithium systems for plasma-facing components at PPPL. LLTS is designed to test operation of liquid lithium under vacuum, including flowing, solidifying (such as would be the case at the end of plasma operations), and re-melting. Constructed of stainless steel, LLTS is a closed loop of pipe with two reservoirs and a pump, as well as diagnostics for temperature, flow rate, and pressure. Since liquid lithium is a highly reactive material, special care must be taken when designing such a system. These include a permanent-magnet MHD pump and MHD flow meter that have no mechanical components in direct contact with the liquid lithium. The LLTS also includes an expandable 24-channel leak-detector interlock system which cuts power to heaters and the pump if any lithium leaks from a pipe joint. Design for the interlock systems and flow meter are presented. This work is supported by US DOE Contract DE-AC02-09CH11466.

  3. An intermediate-scale model for thermal hydrology in low-relief permafrost-affected landscapes

    DOE PAGES

    Jan, Ahmad; Coon, Ethan T.; Painter, Scott L.; ...

    2017-07-10

    Integrated surface/subsurface models for simulating the thermal hydrology of permafrost-affected regions in a warming climate have recently become available, but computational demands of those new process-rich simu- lation tools have thus far limited their applications to one-dimensional or small two-dimensional simulations. We present a mixed-dimensional model structure for efficiently simulating surface/subsurface thermal hydrology in low-relief permafrost regions at watershed scales. The approach replaces a full three-dimensional system with a two-dimensional overland thermal hydrology system and a family of one-dimensional vertical columns, where each column represents a fully coupled surface/subsurface thermal hydrology system without lateral flow. The system is then operatormore » split, sequentially updating the overland flow system without sources and the one-dimensional columns without lateral flows. We show that the app- roach is highly scalable, supports subcycling of different processes, and compares well with the corresponding fully three-dimensional representation at significantly less computational cost. Those advances enable recently developed representations of freezing soil physics to be coupled with thermal overland flow and surface energy balance at scales of 100s of meters. Furthermore developed and demonstrated for permafrost thermal hydrology, the mixed-dimensional model structure is applicable to integrated surface/subsurface thermal hydrology in general.« less

  4. 76 FR 76707 - El Paso Natural Gas Company: Notice of Intent To Prepare an Environmental Assessment for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-08

    ... long, 16-inch diameter lateral pipeline to connect the Douglas Meter Station to EPNG's existing Line No. 2164; The replacement of compressor modules and station yard piping at the existing Willcox Compressor Station; Expansion of the existing Douglas Meter Station by installing updated flow control and pressure...

  5. Meter Designs Reduce Operation Costs for Industry

    NASA Technical Reports Server (NTRS)

    2013-01-01

    Marshall Space Flight Center collaborated with Quality Monitoring and Control (QMC) of Humble, Texas, through a Space Act Agreement to design a balanced flow meter for the Space Shuttle Program. QMC founded APlus-QMC LLC to commercialize the technology, which has contributed to 100 new jobs, approximately $250,000 in yearly sales, and saved customers an estimated $10 million.

  6. The effects of vertical motion on the performance of current meters

    USGS Publications Warehouse

    Thibodeaux, K.G.; Futrell, J. C.

    1987-01-01

    A series of tests to determine the correction coefficients for Price type AA and Price type OAA current meters, when subjected to vertical motion in a towing tank, have been conducted. During these tests, the meters were subjected to vertical travel that ranged from 1.0 to 4.0 ft and vertical rates of travel that ranged from 0.33 to 1.20 ft/sec while being towed through the water at speeds ranging from 0 to 8 ft/sec. The tests show that type AA and type OAA current meters are affected adversely by the rate of vertical motion and the distance of vertical travel. In addition, the tests indicate that when current meters are moved vertically, correction coefficients must be applied to the observed meter velocities to correct for the registration errors that are induced by the vertical motion. The type OAA current meter under-registers and the type AA current meter over-registers in observed meter velocity. These coefficients for the type OAA current meter range from 0.99 to 1.49 and for the type AA current meter range from 0.33 to 1.07. When making current meter measurements from a boat or a cableway, errors in observed current meter velocity will occur when the bobbing of a boat or cableway places the current meter into vertical motion. These errors will be significant when flowing water is < 2 ft/sec and the rate of vertical motion is > 0.3 ft/sec. (Author 's abstract)

  7. Non-invasive flow path characterization in a mining-impacted wetland

    USGS Publications Warehouse

    Bethune, James; Randell, Jackie; Runkel, Robert L.; Singha, Kamini

    2015-01-01

    Time-lapse electrical resistivity (ER) was used to capture the dilution of a seasonal pulse of acid mine drainage (AMD) contamination in the subsurface of a wetland downgradient of the abandoned Pennsylvania mine workings in central Colorado. Data were collected monthly from mid-July to late October of 2013, with an additional dataset collected in June of 2014. Inversion of the ER data shows the development through time of multiple resistive anomalies in the subsurface, which corroborating data suggest are driven by changes in total dissolved solids (TDS) localized in preferential flow pathways. Sensitivity analyses on a synthetic model of the site suggest that the anomalies would need to be at least several meters in diameter to be adequately resolved by the inversions. The existence of preferential flow paths would have a critical impact on the extent of attenuation mechanisms at the site, and their further characterization could be used to parameterize reactive transport models in developing quantitative predictions of remediation strategies.

  8. Dealing with uncertainty in modeling intermittent water supply

    NASA Astrophysics Data System (ADS)

    Lieb, A. M.; Rycroft, C.; Wilkening, J.

    2015-12-01

    Intermittency in urban water supply affects hundreds of millions of people in cities around the world, impacting water quality and infrastructure. Building on previous work to dynamically model the transient flows in water distribution networks undergoing frequent filling and emptying, we now consider the hydraulic implications of uncertain input data. Water distribution networks undergoing intermittent supply are often poorly mapped, and household metering frequently ranges from patchy to nonexistent. In the face of uncertain pipe material, pipe slope, network connectivity, and outflow, we investigate how uncertainty affects dynamical modeling results. We furthermore identify which parameters exert the greatest influence on uncertainty, helping to prioritize data collection.

  9. Wave Turning and Flow Angle in the E-Region Ionosphere

    NASA Astrophysics Data System (ADS)

    Young, M.; Oppenheim, M. M.; Dimant, Y. S.

    2016-12-01

    This work presents results of particle-in-cell (PIC) simulations of Farley-Buneman (FB) turbulence at various altitudes in the high-latitude E-region ionosphere. In that region, the FB instability regularly produces meter-scale plasma irregularities. VHF radars observe coherent echoes via Bragg scatter from wave fronts parallel or anti-parallel to the radar line of sight (LoS) but do not necessarily measure the mean direction of wave propagation. Haldoupis (1984) conducted a study of diffuse radar aurora and found that the spectral width of back-scattered power depends critically on the angle between the radar LoS and the true flow direction, called the flow angle. Knowledge of the flow angle will allow researchers to better interpret observations of coherent back-scatter. Experiments designed to observe meter-scale irregularities in the E-region ionosphere created by the FB instability typically assume that the predominant flow direction is the E×B direction. However, linear theory of Dimant and Oppenheim (2004) showed that FB waves should turn away from E×B and particle-in-cell simulations by Oppenheim and Dimant (2013) support the theory. The present study comprises a quantitative analysis of the dependence of back-scattered power, flow velocity, and spectral width as functions of the flow angle. It also demonstrates that the mean direction of meter-scale wave propagation may differ from the E×B direction by tens of degrees. The analysis includes 2-D and 3-D simulations at a range of altitudes in the auroral ionosphere. Comparison between 2-D and 3-D simulations illustrates the relative importance to the irregularity spectrum of a small but finite component in the direction parallel to B. Previous work has shown this small parallel component to be important to turbulent electron heating and nonlinear transport.

  10. Sediment budget for a polluted Hawaiian reef using hillslope monitoring and process mapping (Invited)

    NASA Astrophysics Data System (ADS)

    Stock, J. D.; Rosener, M.; Schmidt, K. M.; Hanshaw, M. N.; Brooks, B. A.; Tribble, G.; Jacobi, J.

    2010-12-01

    Pollution from coastal watersheds threatens the ecology of the nearshore, including tropical reefs. Suspended sediment concentrations off the reefs of Molokai, Hawaii, chronically exceed a toxic 10 mg/L, threatening reef ecosystems. We hypothesize that historic conversion of hillslope processes from soil creep to overland flow increased both magnitude and frequency of erosion. To create a process sediment budget, we used surficial and ecological mapping, hillslope and stream gages, and novel sensors to locate, quantify and model the generation of fine sediments polluting the reef. Ecological and geomorphic mapping from LiDAR and multi-spectral imagery located overland flow areas with vegetation cover below a threshold preventing erosion. Here, feral goat grazing exposed volcanic soils whose low matrix hydraulic conductivities (1-25 mm/hour) promote Horton overland flow. We instrumented steep, barren hillslopes with soil moisture sensors, overland flow meters, Parshal flumes, ISCO sediment samplers, and a rain gage and conducted repeat Tripod LiDAR and infiltration tests. To characterize soil resistance to overland flow erosion, we used a Cohesive Strength Meter (CSM) to simulate water stress. At the 13.5 km 2 watershed mouth we used a USGS stream gage with an ISCO sediment sampler to estimate total load. Over 3 years, storms triggered overland flow during rainfall intensities above 10-15 mm/hr. Overland flow meters indicate such flows can be up to 3 cm deep, with a tendency to deepen downslope. CSM tests indicate that these depths are insufficient to erode soils where vegetation is dense, but far above threshold values of 2-3 mm for bare soils. Sediment ratings curves for both hillslope and downstream catchment gages show clock-wise hysteresis during the first intense storms in the fall, becoming linear later in the season. During fall storms, sediment concentration is often 10X higher at a given stage. Revised annual lowering rates from experimental hillslopes are 1.5 cm/a (erosion pins), 1.4 cm/a (suspended sediment) and 1.6 cm/a (repeat Tripod LiDAR). These rates are at least 100-fold greater than the long-term river lowering rate of 0.13 mm/a. A sediment budget constructed by extrapolating hillslope lowering rates to the portions of the catchments mapped as unvegetated overland flow predicts a total yearly flux of ~ 6500 t, in agreement with the measured total of ~6200 t. Decadal records illustrate that rainfall intensities sufficient to generate overland flow occur for at least 8-10 hours every year, coincident with 1-3 large storm events. We hypothesize that high lowering rates reflect a combination of long-duration overland flow events, and availability of weathered soils that can be entrained by thin flow. It appears that generation of loose, seasonally weathered silt is a 1st order control on the amount of sediment exported to the reef. If climate change increases storm frequency or duration, or decreases vegetation cover, sediment loading to reefs could increase dramatically.

  11. Local flow management/profile descent algorithm. Fuel-efficient, time-controlled profiles for the NASA TSRV airplane

    NASA Technical Reports Server (NTRS)

    Groce, J. L.; Izumi, K. H.; Markham, C. H.; Schwab, R. W.; Thompson, J. L.

    1986-01-01

    The Local Flow Management/Profile Descent (LFM/PD) algorithm designed for the NASA Transport System Research Vehicle program is described. The algorithm provides fuel-efficient altitude and airspeed profiles consistent with ATC restrictions in a time-based metering environment over a fixed ground track. The model design constraints include accommodation of both published profile descent procedures and unpublished profile descents, incorporation of fuel efficiency as a flight profile criterion, operation within the performance capabilities of the Boeing 737-100 airplane with JT8D-7 engines, and conformity to standard air traffic navigation and control procedures. Holding and path stretching capabilities are included for long delay situations.

  12. Models of the diffuse radar backscatter from Mars

    NASA Technical Reports Server (NTRS)

    England, A. W.; Austin, R. T.

    1991-01-01

    The topographies of several debris flow units near the Mount St. Helens Volcano were measured at lateral scales of millimeters to meters in September 1990. The objective was to measure the surface roughness of the debris flows at scales smaller than, on the order of, and larger that the radar wavelength of common remote sensing radars. A laser profiling system and surveying instruments were used to obtain elevation data for square areas that varied in size from 10 to 32 cm. The elevation data were converted to estimates of the power spectrum of surface roughness. The conversions were based upon standard periodogram techniques, and upon a modified spectral estimation technique that was developed.

  13. 40 CFR 98.323 - Calculating GHG emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the meter automatically corrects for temperature and pressure, replace “520 °R/Ti × Pi/1 atm” with “1... at which flow is measured (°R). Pi = Daily pressure at which flow is measured (atm). 1,440...

  14. Characterization of a Head-Only Aerosol Exposure System for Nonhuman Primates

    DTIC Science & Technology

    2010-01-01

    Alicat Scientific). The flow used provided isokinetic sampling, assuming the presence of laminar flow at the filter inlet, so that the chamber...airflow measured at the chamber inlet using a Gilibrator flow meter (Sensidyne LP) was 29.79±0.88L/min (n= 10; CV=2.97%). With both the aerosol

  15. 40 CFR 98.427 - Records that must be retained.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... transferred CO2 streams and composition. (b) The owner or operator of a CO2 production well facility must maintain quarterly records of the mass flow or volumetric flow of the extracted or transferred CO2 stream and concentration and density if volumetric flow meters are used. (c) Importers or exporters of CO2...

  16. Analytical Models of the Transport of Deep-Well Injectate at the North District Wastewater Treatment Plant, Miami-Dade County, Florida, U.S.A

    NASA Astrophysics Data System (ADS)

    King, J. N.; Walsh, V.; Cunningham, K. J.; Evans, F. S.; Langevin, C. D.; Dausman, A.

    2009-12-01

    The Miami-Dade Water and Sewer Department (MDWASD) injects buoyant effluent from the North District Wastewater Treatment Plant (NDWWTP) through four Class I injection wells into the Boulder Zone---a saline (35 parts per thousand) and transmissive (105 to 106 square meters per day) hydrogeologic unit located approximately 1000 meters below land surface. Miami-Dade County is located in southeast Florida, U.S.A. Portions of the Floridan and Biscayne aquifers are located above the Boulder Zone. The Floridan and Biscayne aquifers---underground sources of drinking water---are protected by U.S. Federal Laws and Regulations, Florida Statutes, and Miami-Dade County ordinances. In 1998, MDWASD began to observe effluent constituents within the Floridan aquifer. Continuous-source and impulse-source analytical models for advective and diffusive transport of effluent are used in the present work to test contaminant flow-path hypotheses, suggest transport mechanisms, and estimate dispersivity. MDWASD collected data in the Floridan aquifer between 1996 and 2007. A parameter estimation code is used to optimize analytical model parameters by fitting model data to collected data. These simple models will be used to develop conceptual and numerical models of effluent transport at the NDWWTP, and in the vicinity of the NDWWTP.

  17. A physical model of ice sheet response to changes in subglacial hydrology

    NASA Astrophysics Data System (ADS)

    Andrews, L. C.; Catania, G. A.; Buttles, J. L.; Andrews, A.; Markowski, M.

    2010-12-01

    Using a physical ice sheet model, we investigate the degree to which motion is controlled by local loss of basal traction versus longitudinal coupling during diurnal, seasonal, and event-type water pulses. Our model can be used to reproduce the spatial pattern and magnitude of ice surface displacements and can aid in the interpretation of ground-based GPS measurements, as it eliminates many of the complicating factors influencing surface velocity measurements. This model consists of a 3 x 1.5 meter plastic box with a grid of holes on the bed used to inject water directly between the interface of the box and a silicone polymer. Water flow is visualized using a colored dye. The polymer response to perturbations in water flow is measured by tracking surface markers through a series of overhead images. We report on a suite of experiments that explore the relationship between water discharge, basal traction, and surface displacements and compare our results to ground-based GPS measurements from a transect in western Greenland.

  18. Testing seismic amplitude source location for fast debris-flow detection at Illgraben, Switzerland

    NASA Astrophysics Data System (ADS)

    Walter, Fabian; Burtin, Arnaud; McArdell, Brian W.; Hovius, Niels; Weder, Bianca; Turowski, Jens M.

    2017-06-01

    Heavy precipitation can mobilize tens to hundreds of thousands of cubic meters of sediment in steep Alpine torrents in a short time. The resulting debris flows (mixtures of water, sediment and boulders) move downstream with velocities of several meters per second and have a high destruction potential. Warning protocols for affected communities rely on raising awareness about the debris-flow threat, precipitation monitoring and rapid detection methods. The latter, in particular, is a challenge because debris-flow-prone torrents have their catchments in steep and inaccessible terrain, where instrumentation is difficult to install and maintain. Here we test amplitude source location (ASL) as a processing scheme for seismic network data for early warning purposes. We use debris-flow and noise seismograms from the Illgraben catchment, Switzerland, a torrent system which produces several debris-flow events per year. Automatic in situ detection is currently based on geophones mounted on concrete check dams and radar stage sensors suspended above the channel. The ASL approach has the advantage that it uses seismometers, which can be installed at more accessible locations where a stable connection to mobile phone networks is available for data communication. Our ASL processing uses time-averaged ground vibration amplitudes to estimate the location of the debris-flow front. Applied to continuous data streams, inversion of the seismic amplitude decay throughout the network is robust and efficient, requires no manual identification of seismic phase arrivals and eliminates the need for a local seismic velocity model. We apply the ASL technique to a small debris-flow event on 19 July 2011, which was captured with a temporary seismic monitoring network. The processing rapidly detects the debris-flow event half an hour before arrival at the outlet of the torrent and several minutes before detection by the in situ alarm system. An analysis of continuous seismic records furthermore indicates that detectability of Illgraben debris flows of this size is unaffected by changing environmental and anthropogenic seismic noise and that false detections can be greatly reduced with simple processing steps.

  19. Cyclic injection, storage, and withdrawal of heated water in a sandstone aquifer at St. Paul, Minnesota--Analysis of thermal data and nonisothermal modeling of short-term test cycles

    USGS Publications Warehouse

    Miller, Robert T.; Delin, G.N.

    2002-01-01

    In May 1980, the University of Minnesota began a project to evaluate the feasibility of storing heated water (150 degrees Celsius) in the Franconia-Ironton Galesville aquifer (183 to 245 meters below land surface) and later recovering it for space heating. The University's steam-generation facilities supplied high-temperature water for injection. The Aquifer Thermal-Energy Storage system is a doublet-well design in which the injection-withdrawal wells are spaced approximately 250 meters apart. Water was pumped from one of the wells through a heat exchanger, where heat was added or removed. This water was then injected back into the aquifer through the other well. Four short-term test cycles were completed. Each cycle consisted of approximately equal durations of injection and withdrawal ranging from 5.25 to 8.01 days. Equal rates of injection and withdrawal, ranging from 17.4 to 18.6 liters per second, were maintained for each short-term test cycle. Average injection temperatures ranged from 88.5 to 117.9 degrees Celsius. Temperature graphs for selected depths at individual observation wells indicate that the Ironton and Galesville Sandstones received and stored more thermal energy than the upper part of the Franconia Formation. Clogging of the Ironton Sandstone was possibly due to precipitation of calcium carbonate or movement of fine-grain material or both. Vertical-profile plots indicate that the effects of buoyancy flow were small within the aquifer. A three-dimensional, anisotropic, nonisothermal, ground-water-flow, and thermal-energy-transport model was constructed to simulate the four short-term test cycles. The model was used to simulate the entire short-term testing period of approximately 400 days. The only model properties varied during model calibration were longitudinal and transverse thermal dispersivities, which, for final calibration, were simulated as 3.3 and 0.33 meters, respectively. The model was calibrated by comparing model-computed results to (1) measured temperatures at selected altitudes in four observation wells, (2) measured temperatures at the production well, and (3) calculated thermal efficiencies of the aquifer. Model-computed withdrawal-water temperatures were within an average of about 3 percent of measured values and model-computed aquifer-thermal efficiencies were within an average of about 5 percent of calculated values for the short-term test cycles. These data indicate that the model accurately simulated thermal-energy storage within the Franconia-Ironton-Galesville aquifer.

  20. Geohydrologic and drill-hole data for test well USW H-4, Yucca Mountain, Nye County, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whitfield, M.S. Jr.; Thordarson, W.; Eshom, E.P.

    This report presents data on drilling operations, lithology, geophysical well logs, sidewall-core samples, water-level monitoring, pumping tests, injection tests, radioactive-tracer borehole flow survey, and water chemistry for test well USW H-4. The well is one of a series of test wells drilled in the southwestern part of the Nevada Test Site, Nye County, Nevada, in cooperation with the US Department of Energy. These test wells are part of the Nevada Nuclear Waste Storage Investigations to identify sites for storage of high-level radioactive wastes. Test well USW H-4 was drilled in ash-flow tuff to a total depth of 1219 meters. Depthmore » to water below land surface was 519 meters, or at an altitude of 730 meters above sea level. After test pumping at a rate of 17.4 liters per second for approximately 9 days, the drawdown was 4.85 meters. A radioactive borehole-flow survey indicated that the Bullfrog Member of the Crater Flat Tuff (Tertiary age) was the most productive geologic unit, producing 36.5 percent of the water in the well. The second most productive geologic unit was the Tram Member of the Crater Flat Tuff, which produced 32 percent of the water. The water in test well USW H-4 is predominantly a soft, sodium bicarbonate type of water typical of water produced in tuffaceous rocks in southern Nevada. 7 references, 26 figures, 9 tables.« less

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