Science.gov

Sample records for air inlet openings

  1. Wind-Tunnel Investigation of Air Inlet and Outlet Openings on a Streamline Body

    NASA Technical Reports Server (NTRS)

    Becker, John V

    1951-01-01

    In connection with the general problem of providing air flow to an aircraft power plant located within a fuselage, an investigation was conducted in the Langley 8-foot high-speed tunnel to determine the effect on external drag and pressure distribution of air inlet openings located at the nose of a streamline body. Air outlet openings located at the tail and at the 21-percent and 63-percent stations of the body were also investigated. Boundary layer transition measurements were made and correlated with the force and the pressure data. Individual openings were investigated with the aid of a blower and then practicable combinations of inlet and outlet openings were tested. Various modifications to the internal duct shape near the inlet opening and the aerodynamic effects of a simulated gun in the duct were also studied. The results of the tests suggested that outlet openings should be designed so that the static pressure of the internal flow at the outlet would be the same as the static pressure of the external flow in the vicinity of the opening.

  2. Wind-Tunnel Investigation of Air Inlet and Outlet Openings for Aircraft, Special Report

    NASA Technical Reports Server (NTRS)

    Rogallo, Francis M.; Gauvain, William E.

    1938-01-01

    An investigation was made in the NACA 5-foot vertical wind tunnel of a large variety of duct inlets and outlets to obtain information relative to their design for the cooling or the ventilation systems on aircraft. Most of the tests were of openings in a flat plate but, in order to determine the best locations and the effects of interference, a few tests were made of openings in an airfoil. The best inlet location for a system not including a blower was found to be at the forward stagnation point; for one including a blower, the best location was found to be in the region of lowest total head, probably in the boundary layer near the trailing edge. Design recommendations are given, and it is shown that correct design demands a knowledge of the external flow and of the internal requirements in addition to that obtained from the results of the wind tunnel tests.

  3. Open inlet conversion: Water quality benefits of two designs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentr...

  4. Cooling Air Inlet and Exit Geometries on Aircraft Engine Installations

    NASA Technical Reports Server (NTRS)

    Katz, Joseph; Corsiglia, Victor R.; Barlow, Philip R.

    1982-01-01

    A semispan wing and nacelle of a typical general aviation twin-engine aircraft was tested to evaluate the cooling capability and drag or several nacelle shapes; the nacelle shapes included cooling air inlet and exit variations. The tests were conducted in the Ames Research Center 40 x 80-ft Wind Tunnel. It was found that the cooling air inlet geometry of opposed piston engine installations has a major effect on inlet pressure recovery, but only a minor effect on drag. Exit location showed large effect on drag, especially for those locations on the sides of the nacelle where the suction characteristics were based on interaction with the wing surface pressures.

  5. Aerodynamic characteristics of a series of single-inlet air-breathing missile configurations

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configured with either a single axisymmetric or a two dimensional inlet located at the bottom of the body. Two tail configurations were investigated: a tri-tail and an X-tail. The tail surfaces could be deflected to provide pitch control. A wing could be located above the inlet on the center line of the model. Tests were made at supersonic Mach numbers with the inlet open and internal flow, and at subsonic-transonic Mach numbers with the internal duct closed and no internal flow.

  6. Alpha-environmental continuous air monitor inlet

    DOEpatents

    Rodgers, John C.

    2003-01-01

    A wind deceleration and protective shroud that provides representative samples of ambient aerosols to an environmental continuous air monitor (ECAM) has a cylindrical enclosure mounted to an input on the continuous air monitor, the cylindrical enclosure having shrouded nozzles located radially about its periphery. Ambient air flows, often along with rainwater flows into the nozzles in a sampling flow generated by a pump in the continuous air monitor. The sampling flow of air creates a cyclonic flow in the enclosure that flows up through the cylindrical enclosure until the flow of air reaches the top of the cylindrical enclosure and then is directed downward to the continuous air monitor. A sloped platform located inside the cylindrical enclosure supports the nozzles and causes any moisture entering through the nozzle to drain out through the nozzles.

  7. 47. View of "dry air inlets" to waveguides entering scanner ...

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

    47. View of "dry air inlets" to waveguides entering scanner building 105. Dried air is generated under pressure by Ingersoll-Rand dehumidified/dessicator and compressor system. View is at entrance from passageway that links into corner of scanner building. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  8. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Cook Inlet Intrastate Air...

  9. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2014-07-01 2014-07-01 false Cook Inlet Intrastate Air...

  10. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2013-07-01 2013-07-01 false Cook Inlet Intrastate Air...

  11. The effect of inlet air vitiation on combustion efficiency

    SciTech Connect

    Zuomin, F.; Yijun, J.

    1985-01-01

    Experimental results of the effect of inlet air vitiation produced by a vitiating preheater on combustion efficiency of a turbojet combustor and a model ramjet combustor are presented in this paper. An empirical correlation and a calculation method based on stirred reactor theory are derived to correct the vitiation effect. Results obtained by means of these two methods are in good agreement with test data.

  12. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  13. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  14. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  15. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  16. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  17. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Cook Inlet Intrastate Air Quality...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook...

  18. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Cook Inlet Intrastate Air Quality...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook...

  19. Investigation of Aerodynamic and Icing Characteristics of a Flush Alternate Inlet Induction System Air Scoop

    NASA Technical Reports Server (NTRS)

    Lewis, James P.

    1953-01-01

    An investigation has been made in the NACA Lewis icing research tunnel to determine the aerodynamic and icing characteristics of a full-scale induction-system air-scoop assembly incorporating a flush alternate inlet. The flush inlet was located immediately downstream of the offset ram inlet and included a 180 deg reversal and a 90 deg elbow in the ducting between inlet and carburetor top deck. The model also had a preheat-air inlet. The investigation was made over a range of mass-air- flow ratios of 0 to 0.8, angles of attack of 0 and 4 deg airspeeds of 150 to 270 miles per hour, air temperatures of 0 and 25 F various liquid-water contents, and droplet sizes. The ram inlet gave good pressure recovery in both clear air and icing but rapid blockage of the top-deck screen occurred during icing. The flush alternate inlet had poor pressure recovery in both clear air and icing. The greatest decreases in the alternate-inlet pressure recovery were obtained at icing conditions of low air temperature and high liquid-water content. No serious screen icing was observed with the alternate inlet. Pressure and temperature distributions on the carburetor top deck were determined using the preheat-air supply with the preheat- and alternate-inlet doors in various positions. No screen icing occurred when the preheat-air system was operated in combination with alternate-inlet air flow.

  20. Swozzle based burner tube premixer including inlet air conditioner for low emissions combustion

    DOEpatents

    Tuthill, Richard Sterling; Bechtel, II, William Theodore; Benoit, Jeffrey Arthur; Black, Stephen Hugh; Bland, Robert James; DeLeonardo, Guy Wayne; Meyer, Stefan Martin; Taura, Joseph Charles; Battaglioli, John Luigi

    2002-01-01

    A burner for use in a combustion system of a heavy-duty industrial gas turbine includes a fuel/air premixer having an air inlet, a fuel inlet, and an annular mixing passage. The fuel/air premixer mixes fuel and air into a uniform mixture for injection into a combustor reaction zone. The burner also includes an inlet flow conditioner disposed at the air inlet of the fuel/air premixer for controlling a radial and circumferential distribution of incoming air. The pattern of perforations in the inlet flow conditioner is designed such that a uniform air flow distribution is produced at the swirler inlet annulus in both the radial and circumference directions. The premixer includes a swozzle assembly having a series of preferably air foil shaped turning vanes that impart swirl to the airflow entering via the inlet flow conditioner. Each air foil contains internal fuel flow passages that introduce natural gas fuel into the air stream via fuel metering holes that pass through the walls of the air foil shaped turning vanes. By injecting fuel in this manner, an aerodynamically clean flow field is maintained throughout the premixer. By injecting fuel via two separate passages, the fuel/air mixture strength distribution can be controlled in the radial direction to obtain optimum radial concentration profiles for control of emissions, lean blow outs, and combustion driven dynamic pressure activity as machine and combustor load are varied.

  1. Inlet boundary conditions for shock wave propagation problems in air ducts

    NASA Astrophysics Data System (ADS)

    Fashbaugh, R. H.

    1992-03-01

    Shock waves propagating into air ducting systems are numerically studied using data from Kriebel (1972). Small-scale junctions mounted in shock tubes with an incident shock wave are considered. The stagnation pressure ratio through a duct inlet is evaluated for various junction types. The logarithm of this ratio varies linearly with the Mach number of the flow behind the incident shock wave. The static pressure inside the inlet is established using experimental data with given Mach numbers of the incident and inlet flows. A constant stagnation enthalpy through the inlet junction is assumed to establish inflow to the duct.

  2. Numerical Investigation of Engine Inlet Vane Hot-Air Anti-Icing System with Surface Air Film

    NASA Astrophysics Data System (ADS)

    Ma, Hui; Chen, Weijian; Zhang, Dalin

    The inlet vane of aircraft engine needs to be equipped with anti-icing system to prevent ice accretion on the leading edge due to flight safety requirements, and the engine bleed hot-air is mostly used to heat the vane surface in anti-icing system. In order to save the energy consumption, a new anti-icing structure was developed and investigated with numerical simulation. Besides the use of small tunnels to enhance the heat transfer characteristics, a narrow gap was opened and assigned on the vane surface at the end of the anti-icing tunnels, and the exhaust hot-air was released from the gap to form an air film on the outside surface, which was supposed to prevent the droplets from impinging to the surface and sweep the droplets away. The droplets impingement on the vane surface was investigated by solving the 3D Eulerian air/droplets twophase model, and the impingement results were compared with the original system. Meanwhile, the thermodynamic analysis of the anti-icing system was presented in this paper. The results indicate that the air film is effective to decrease the droplets impingement area, and the new structure could provide more heat flux for anti-icing than the regular anti-icing structure.

  3. Solar assist and filter construction for dryer inlet

    SciTech Connect

    Commander, B.C.

    1981-07-21

    An air inlet construction for a domestic clothes dryer is described including a pair of selectively usable air inlet ports. One of the air inlet ports opens outwardly to the area immediately adjacent and exterior of the dryer and the other inlet port opens into the interior of a non-domestically heated portion of the building in which the dryer is disposed, but which portion is subject to being heated by solar energy during the daylight hours.

  4. Advantages of air conditioning and supercharging an LM6000 gas turbine inlet

    SciTech Connect

    Kolp, D.A.; Flye, W.M.; Guidotti, H.A.

    1995-07-01

    Of all the external factors affecting a gas turbine, inlet pressure and temperature have the greatest impact on performance. The effect of inlet temperature variations is especially pronounced in the new generation of high-efficiency gas turbines typified by the 40 MW GE LM6000. A reduction of 50 F (28 C) in inlet temperature can result in a 30 percent increase in power and a 4.5 percent improvement in heat rate. An elevation increase to 5,000 ft (1,524 m) above sea level decreases turbine output 17 percent; conversely supercharging can increase output more than 20 percent. This paper addresses various means of heating, cooling and supercharging LM6000 inlet air. An economic model is developed and sample cases are cited to illustrate the optimization of gas turbine inlet systems, taking into account site conditions, incremental equipment cost and subsequent performance enhancement.

  5. Aerodynamic characteristics of a series of twin-inlet air-breathing missile configurations. 2: Two-dimensional inlets at supersonic speeds

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configured with either twin axisymmetric or two dimensional inlets. Three circumferential inlet locations were investigated: 90 deg, 115 deg, and 135 deg from the top center. Two vertical wing locations, as well as wingless configurations, were used. Three tail configurations were formed by locating the tail surfaces either on the inlet fairings or on fairings on the body. The surfaces were used to provide pitch control. Two dimensional inlets with extended compression surfaces, used to improve the angle-of-attack performance of the inlets for wingless configurations, were also investigated. The two dimensional inlet configurations are covered.

  6. Effect of inlet-air humidity on the formation of oxides of nitrogen in a gas-turbine combustor

    NASA Technical Reports Server (NTRS)

    Marchionna, N. R.

    1973-01-01

    Tests were conducted to determine the effect of inlet-air humidity on the formation of oxides of nitrogen from a gas-turbine combustor. Combustor inlet-air temperature ranged from 450 F to 1050 F. The tests were run at a constant pressure of 6 atmospheres and reference Mach number of 0.065. The NO sub x emission index was found to decrease with increasing inlet-air humidity at a constant exponential rate of 19 percent per mass percent water vapor in the air. This decrease of NO sub x emission index with increasing humidity was found to be independent of inlet-air temperature.

  7. Performance Prediction of Darrieus-Type Hydroturbine with Inlet Nozzle Operated in Open Water Channels

    NASA Astrophysics Data System (ADS)

    Nakashima, K.; Watanabe, S.; Matsushita, D.; Tsuda, S.; Furukawa, A.

    2016-11-01

    Small hydropower is one of the renewable energies and is expected to be effectively used for local supply of electricity. We have developed Darrieus-type hydro-turbine systems, and among them, the Darrieus-turbine with a weir and a nozzle installed upstream of turbine is, so far, in success to obtain more output power by gathering all water into the turbine. However, there can several cases exist, in which installing the weir covering all the flow channel width is unrealistic, and in such cases, the turbine should be put alone in open channels without upstream weir. Since the output power is very small in such a utilization of small hydropower, it is important to derive more power for the cost reduction. In the present study, we parametrically investigate the preferable shape of the inlet nozzle for the Darrieus-type hydroturbine operated in an open flow channel. Experimental investigation is carried out in the open channel in our lab. Tested inlet nozzles are composed of two flat plates with the various nozzle converging angles and nozzle outlet (runner inlet) widths with the nozzle inlet width kept constant. As a result, the turbine with the nozzles having large converging angle and wide outlet width generates higher power. Two-dimensional unsteady numerical simulation is also carried out to qualitatively understand the flow mechanism leading to the better performance of turbine. Since the depth, the width and the flow rate in the real open flow channels are different from place to place and, in some cases from time to time, it is also important to predict the onsite performance of the hydroturbine from the lab experiment at planning stage. One-dimensional stream-tube model is developed for this purpose, in which the Darrieus-type hydroturbine with the inlet nozzle is considered as an actuator-disk modelled based on our experimental and numerical results.

  8. Apparatus and Method for Measuring Air Temperature Ahead of an Aircraft for Controlling a Variable Inlet/Engine Assembly

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L. (Inventor)

    2001-01-01

    The apparatus and method employ remote sensing to measure the air temperature a sufficient distance ahead of the aircraft to allow time for a variable inlet/engine assembly to be reconfigured in response to the measured temperature, to avoid inlet unstart and/or engine compressor stall. In one embodiment, the apparatus of the invention has a remote sensor for measuring at least one air temperature ahead of the vehicle and an inlet control system for varying the inlet. The remote sensor determines a change in temperature value using at least one temperature measurement and prior temperature measurements corresponding to the location of the aircraft. The control system uses the change in air temperature value to vary the inlet configuration to maintain the position of the shock wave during the arrival of the measured air in the inlet. In one embodiment, the method of the invention includes measuring at least one air temperature ahead of the vehicle, determining an air temperature at the vehicle from prior air temperature measurements, determining a change in temperature value using the air temperature at the vehicle and the at least one air temperature measurement ahead of the vehicle, and using the change in temperature value to-reposition the airflow inlet, to cause the shock wave to maintain substantially the same position within the inlet as the airflow temperature changes within the inlet.

  9. Improving the performance of a compression ignition engine by directing flow of inlet air

    NASA Technical Reports Server (NTRS)

    Kemper, Carlton

    1946-01-01

    The object of this report is to present the results of tests performed by the National Advisory Committee for Aeronautics to determine the effect on engine performance of directing the flow of the inlet air to a 5-inch by 7-inch cylinder, solid injection, compression ignition engine, After a few preliminary tests, comparative runs were made at a speed of 1500 r.p.m. with and without directed air flow. It was found that directing the flow of the inlet air toward the fuel injection valve gave steadier engine operation, and an appreciable increase in power, and decreased fuel consumption. The results indicate the possibility of improving the performance of a given type of combustion chamber without changing its shape and with no change in valve timing. They would also seem to prove that directional turbulence, set up before the inlet valve of a four-stroke cycle engine, continues in the engine cylinder throughout the compression stroke.

  10. A comparative assessment of alternative combustion turbine inlet air cooling system

    SciTech Connect

    Brown, D.R.; Katipamula, S.; Konynenbelt, J.H.

    1996-02-01

    Interest in combustion turbine inlet air cooling (CTAC) has increased during the last few years as electric utilities face increasing demand for peak power. Inlet air cooling increases the generating capacity and decreases the heat rate of a combustion turbine during hot weather when the demand for electricity is generally the greatest. Several CTAC systems have been installed, but the general applicability of the concept and the preference for specific concepts is still being debated. Concurrently, Rocky Research of Boulder City, Nevada has been funded by the U.S. Department of Energy to conduct research on complex compound (ammoniated salt) chiller systems for low-temperature refrigeration applications.

  11. Problems in creation of modern air inlet filters of power gas turbine plants in Russia and methods of their solving

    NASA Astrophysics Data System (ADS)

    Mikhaylov, V. E.; Khomenok, L. A.; Sherapov, V. V.

    2016-08-01

    The main problems in creation and operation of modern air inlet paths of gas turbine plants installed as part of combined-cycle plants in Russia are presented. It is noted that design features of air inlet filters shall be formed at the stage of the technical assignment not only considering the requirements of gas turbine plant manufacturer but also climatic conditions, local atmospheric air dustiness, and a number of other factors. The recommendations on completing of filtration system for air inlet filter of power gas turbine plants depending on the facility location are given, specific defects in design and experience in operation of imported air inlet paths are analyzed, and influence of cycle air preparation quality for gas turbine plant on value of operating expenses and cost of repair works is noted. Air treatment equipment of various manufacturers, influence of aerodynamic characteristics on operation of air inlet filters, features of filtration system operation, anti-icing system, weather canopies, and other elements of air inlet paths are considered. It is shown that nonuniformity of air flow velocity fields in clean air chamber has a negative effect on capacity and aerodynamic resistance of air inlet filter. Besides, the necessity in installation of a sufficient number of differential pressure transmitters allowing controlling state of each treatment stage not being limited to one measurement of total differential pressure in the filtration system is noted in the article. According to the results of the analysis trends and methods for modernization of available equipment for air inlet path, the importance of creation and implementation of new technologies for manufacturing of filtering elements on sites of Russia within the limits of import substitution are given, and measures on reliability improvement and energy efficiency for air inlet filter are considered.

  12. Bathymetry Estimates on Open Beaches and in Tidal Inlets via Remote Sensing

    NASA Astrophysics Data System (ADS)

    Honegger, D.; Haller, M. C.; Holman, R. A.

    2014-12-01

    Despite its vital importance to coastal hydrodynamics and maritime safety, bathymetry is often unknown or poorly constrained; remote sensing techniques show promise to help fill this gap. It has been shown that spatial gradients of cross-spectral phase can be successfully exploited to estimate highly-resolved, frequency-dependent wavenumber vectors in wave resolving image time series. These frequency-wavenumber vector pairs have proven useful for bathymetry estimation not only through basic inversion of the linear dispersion relation, but also through more complex data assimilation schemes. However, previous efforts are generally limited to open beaches. As part of the DARLA and RIVET I/II experiments (Duck, NC; New River Inlet, NC; Columbia River Mouth, OR/WA), we present application of this methodology to two complementary remote sensors (X-band marine radar and optical video) and to a range of environments, from simple (open beach) to complex (a micro-tidal inlet mouth and an energetic meso-tidal estuary mouth). Bathymetry estimates via linear wave theory (the "cBathy" algorithm), spatially resolved on the order of one wavelength, are shown to reproduce bar gaps along open beaches and the structure of ebb-tidal shoals. These quasi-continuous estimates are provided at significantly greater resolution than those calculated via 3D-FFT methods over similar domain sizes (up to 40+ km2). Mean currents can affect depth inversion estimates through the Doppler shift of the wave field. As the effect scales with the current vector component in the direction of the waves, this term is often negligible on open beaches, but it becomes significant near tidal inlets. Tidal averaging of the Doppler effect induces a depth estimate bias, but it does not appreciably deteriorate depth estimate accuracy in the presence of low-amplitude, oscillatory tidal currents. Additionally, if slack-water events can be identified, the problem can be divided into separate depth- and current-inversions.

  13. Operational test report for 241-AW tank inlet air control stations

    SciTech Connect

    Minteer, D.J., Westinghouse Hanford

    1996-07-03

    This document reports the results of operational testing on tank inlet air control stations in 241-AW tank farm. An air control station was installed on each of the six AW tanks. Operational testing consisted of a simple functional test of each station`s air flow controller, aerosol testing of each station`s HEPA filter, and final ventilation system balancing (i.e., tank airflows and vacuum level) using the air control stations. The test was successful and the units were subsequently placed into operation.

  14. The Role of Design-of-Experiments in Managing Flow in Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Gridley, Marvin C.; Agrell, Johan

    2003-01-01

    It is the purpose of this study to demonstrate the viability and economy of Design-of-Experiments methodologies to arrive at microscale secondary flow control array designs that maintain optimal inlet performance over a wide range of the mission variables and to explore how these statistical methods provide a better understanding of the management of flow in compact air vehicle inlets. These statistical design concepts were used to investigate the robustness properties of low unit strength micro-effector arrays. Low unit strength micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. The term robustness is used in this paper in the same sense as it is used in the industrial problem solving community. It refers to minimizing the effects of the hard-to-control factors that influence the development of a product or process. In Robustness Engineering, the effects of the hard-to-control factors are often called noise , and the hard-to-control factors themselves are referred to as the environmental variables or sometimes as the Taguchi noise variables. Hence Robust Optimization refers to minimizing the effects of the environmental or noise variables on the development (design) of a product or process. In the management of flow in compact inlets, the environmental or noise variables can be identified with the mission variables. Therefore this paper formulates a statistical design methodology that minimizes the impact of variations in the mission variables on inlet performance and demonstrates that these statistical design concepts can lead to simpler inlet flow management systems.

  15. Italy: An Open Air Museum

    NASA Astrophysics Data System (ADS)

    Pizzorusso, Ann

    2016-04-01

    Imagine if you could see the River Styx, bathe in the Fountain of Youth, collect water which enhances fertility, wear a gem that heals bodily ailments, understand how our health is affected by geomagnetic fields, venture close to the flames of Hell on Earth and much, much, more. Know something? These things exist - on Earth - today - in Italy and you can visit them because Italy is an open air museum. Ann C. Pizzorusso, in her recent book, reveals how Italy's geology has affected its art, literature, architecture, religion, medicine and just about everything else. She explores the geologic birth of the land, describing the formation of the Alps and Apennines, romantic bays of Tuscany and Lazio, volcanoes of the south and Caribbean-like beaches of Puglia. But that's not all, from the first pages of this visually stunning book, the reader has the impression of being in an art museum, where one can wander from page to page to satisfy one's curiosity-- guided from time to time by the Etruscan priests, Virgil, Dante, Goethe or Leonardo da Vinci himself. Pizzorusso stitches together widely diverse topics - such as gemology, folk remedies, grottoes, painting, literature, physics and religion - using geology as a thread. Quoting everyone from Pliny the Elder to NASA physicist Friedemann Freund, the work is solidly backed scholarship that reads as easily as a summer novel. Wonderfully illustrated with many photos licensed from Italian museums, HRH Elizabeth II and the Ministero Beni Culturali the book highlights the best works in Italian museums and those outside in the "open air museums." This approach can be used in any other country in the world and can be used for cultural tourism (a tour following the book has been organized for cultural and university groups), an ideal way of linking museums to the surrounding landscape.

  16. Benefits of compressor inlet air cooling for gas turbine cogeneration plants

    SciTech Connect

    De Lucia, M.; Lanfranchi, C.; Boggio, V.

    1996-07-01

    Compressor inlet air cooling is an effective method for enhancing the performance of gas turbine plants. This paper presents a comparative analysis of different solutions for cooling the compressor inlet air for the LM6000 gas turbine in a cogeneration plant operated in base load. Absorption and evaporative cooling systems are considered and their performance and economic benefits compared for the dry low-NO{sub x} LM6000 version. Reference is made to two sites in Northern and Southern Italy, whose climate data series for modeling the variations in ambient temperature during the single day were used to account for the effects of climate in the simulation. The results confirmed the advantages of inlet air cooling systems. In particular, evaporative cooling proved to be cost effective, though capable of supplying only moderate cooling, while absorption systems have a higher cost but are also more versatile and powerful in base-load operation. An integration of the two systems proved to be able to give both maximum performance enhancement and net economic benefit.

  17. Environmental continuous air monitor inlet with combined preseparator and virtual impactor

    DOEpatents

    Rodgers, John C.

    2007-06-19

    An inlet for an environmental air monitor is described wherein a pre-separator interfaces with ambient environment air and removes debris and insects commonly associated with high wind outdoors and a deflector plate in communication with incoming air from the pre-separator stage, that directs the air radially and downward uniformly into a plurality of accelerator jets located in a manifold of a virtual impactor, the manifold being cylindrical and having a top, a base, and a wall, with the plurality of accelerator jets being located in the top of the manifold and receiving the directed air and accelerating directed air, thereby creating jets of air penetrating into the manifold, where a major flow is deflected to the walls of the manifold and extracted through ports in the walls. A plurality of receiver nozzles are located in the base of the manifold coaxial with the accelerator jets, and a plurality of matching flow restrictor elements are located in the plurality of receiver nozzles for balancing and equalizing the total minor flow among all the plurality of receiver nozzles, through which a lower, fractional flow extracts large particle constituents of the air for collection on a sample filter after passing through the plurality of receiver nozzles and the plurality of matching flow restrictor elements.

  18. Design Evolution and Performance Characterization of the GTX Air-Breathing Launch Vehicle Inlet

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Steffen, C. J., Jr.; Rice, T.; Trefny, C. J.

    2002-01-01

    The design and analysis of a second version of the inlet for the GTX rocket-based combine-cycle launch vehicle is discussed. The previous design did not achieve its predicted performance levels due to excessive turning of low-momentum comer flows and local over-contraction due to asymmetric end-walls. This design attempts to remove these problems by reducing the spike half-angle to 10- from 12-degrees and by implementing true plane of symmetry end-walls. Axisymmetric Reynolds-Averaged Navier-Stokes simulations using both perfect gas and real gas, finite rate chemistry, assumptions were performed to aid in the design process and to create a comprehensive database of inlet performance. The inlet design, which operates over the entire air-breathing Mach number range from 0 to 12, and the performance database are presented. The performance database, for use in cycle analysis, includes predictions of mass capture, pressure recovery, throat Mach number, drag force, and heat load, for the entire Mach range. Results of the computations are compared with experimental data to validate the performance database.

  19. 35. James River Visitor Center. Opened as an open air ...

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

    35. James River Visitor Center. Opened as an open air visitor center in 1962, it was enclosed and a heating system installed in 1984 to allow use through the cooler months and help reduce vandalism. Looking northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  20. Nonuniform air flow in inlets: the effect on filter deposits in the fiber sampling cassette.

    PubMed

    Baron, P A; Chen, C C; Hemenway, D R; O'Shaughnessy, P

    1994-08-01

    Smoke stream studies were combined with a new technique for visualizing a filter deposit from samples used to monitor asbestos or other fibers. Results clearly show the effect of secondary flow vortices within the sampler under anisoaxial sampling conditions. The vortices observed at low wind velocities occur when the inlet axis is situated at angles between 45 degrees and 180 degrees to the motion of the surrounding air. It is demonstrated that the vortices can create a complex nonuniform pattern in the filter deposit, especially when combined with particle settling or electrostatic interactions between the particles and the sampler. Inertial effects also may play a role in the deposit nonuniformity, as well as causing deposition on the cowl surfaces. Changes in the sampler, such as its placement, may reduce these biases. The effects noted are not likely to occur in all sampling situations, but may explain some reports of high variability on asbestos fiber filter samples. The flow patterns observed in this study are applicable to straight, thin-walled inlets. Although only compact particles were used, the air flow patterns and forces involved will have similar effects on fibers of the same aerodynamic diameter.

  1. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to... and 115AW) § 179.220-17 Gauging devices, top loading and unloading devices, venting and air...

  2. Performance and economic enhancement of cogeneration gas turbines through compressor inlet air cooling

    NASA Astrophysics Data System (ADS)

    Delucia, M.; Bronconi, R.; Carnevale, E.

    1994-04-01

    Gas turbine air cooling systems serve to raise performance to peak power levels during the hot months when high atmospheric temperatures cause reductions in net power output. This work describes the technical and economic advantages of providing a compressor inlet air cooling system to increase the gas turbine's power rating and reduce its heat rate. The pros and cons of state-of-the-art cooling technologies, i.e., absorption and compression refrigeration, with and without thermal energy storage, were examined in order to select the most suitable cooling solution. Heavy-duty gas turbine cogeneration systems with and without absorption units were modeled, as well as various industrial sectors, i.e., paper and pulp, pharmaceuticals, food processing, textiles, tanning, and building materials. The ambient temperature variations were modeled so the effects of climate could be accounted for in the simulation. The results validated the advantages of gas turbine cogeneration with absorption air cooling as compared to other systems without air cooling.

  3. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    NASA Technical Reports Server (NTRS)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  4. Towards printable open air microfluidics.

    SciTech Connect

    Collord, Andrew; Cook, Adam W.; Clem, Paul Gilbert; Fenton, Kyle Ross; Apblett, Christopher Alan; Branson, Eric D.

    2010-04-01

    We have demonstrated a novel microfluidic technique for aqueous media, which uses super-hydrophobic materials to create microfluidic channels that are open to the atmosphere. We have demonstrated the ability to perform traditional electrokinetic operations such as ionic separations and electrophoresis using these devices. The rate of evaporation was studied and found to increase with decreasing channel size, which places a limitation on the minimum size of channel that could be used for such a device.

  5. Effect of Fuel-Air Ratio, Inlet Temperature, and Exhaust Pressure on Detonation

    NASA Technical Reports Server (NTRS)

    Taylor, E S; Leary, W A; Diver, J R

    1940-01-01

    An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Results showed that for any given maximum pressure the maximum permissible end-gas temperature increased as the fuel-air ratio was increased. The tendency to detonate was slightly reduced by an increase in residual gas content resulting from an increase in exhaust backpressure with inlet pressure constant.

  6. The comparative performance of an aviation engine at normal and high inlet air temperatures

    NASA Technical Reports Server (NTRS)

    Gardiner, Arthur W; Schey, Oscar W

    1928-01-01

    This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without intercooling when using plain aviation gasoline and mixtures of benzol and gasoline. The results show that for the conditions of test, both the brake and indicated power decrease with increase in air temperature at a faster rate than given by the theoretical assumption that power varies inversely as the square root of the absolute temperature. On a brake basis, the order of the difference in power for a temperature difference of 120 degrees F. Is 3 to 5 per cent. The observed relation between power and temperature when using the 30-70 blend was found to be linear. But, although these differences are noted, the above theoretical assumption may be considered as generally applicable except where greater precision over a wide range of temperatures is desired, in which case it appears necessary to test the particular engine under the given conditions. (author)

  7. Christmas in the open air.

    PubMed

    1991-12-18

    'What health problems? I'm bloody fit, me,' said Brian, a homeless man, who is not one to whinge and whine about his health. Brian and his mate 'Bob Dylan', each wearing a couple of T-shirts, a jumper and an overcoat, crack jokes and compete to tell their most gruesome injury tale. It is two weeks before Christmas and they sit, snuggled into a sleeping bag amid the blankets and newspaper sheets of other homeless people who occupy the disused bandstand in London's Lincoln's Inn Fields. They drink one of several cans of extra strong lager and share a cigarette. The weather is freezing and as the sun goes down the wind picks up. The rotting wooden bandstand is the focal point for homeless people in 'the Fields' and, although it's open to the elements, its roof means the ground stays dry. Nearby are three concrete tennis courts where Holborn office workers practise their forehands. The fencing that separates the courts from the green is a support for numerous bashes -cardboard and tarpaulin structures literally bashed together - where more homeless people live.

  8. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Gauging devices, top loading and unloading devices... and 115AW) § 179.200-16 Gauging devices, top loading and unloading devices, venting and air inlet...). In no case shall the wall thickness be less than that specified in § 179.201-1. (f) When top...

  9. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to... DOT-111AW and 115AW) § 179.220-17 Gauging devices, top loading and unloading devices, venting and...

  10. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.200-16 Section 179.200-16 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  11. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  12. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.200-16 Section 179.200-16 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  13. EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN ...

    EPA Pesticide Factsheets

    A detailed literature search was performed to collect and collate available data reporting emissions of toxic organic substances into the air from open burning sources. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) data were available for many of the sources. Data on semivolatile organic compounds (SVOCs) that are not PAHs were available for several sources. Carbonyl and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran (PCDD/F) data were available for only a few sources. There were several sources for which no emissions data were available at all. Several observations were made including: 1) Biomass open burning sources typically emitted less VOCs than open burning sources with anthropogenic fuels on a mass emitted per mass burned basis, particularly those where polymers were concerned; 2) Biomass open burning sources typically emitted less SVOCs and PAHs than anthropogenic sources on a mass emitted per mass burned basis. Burning pools of crude oil and diesel fuel produced significant amounts of PAHs relative to other types of open burning. PAH emissions were highest when combustion of polymers was taking place; and 3) Based on very limited data, biomass open burning sources typically produced higher levels of carbonyls than anthropogenic sources on a mass emitted per mass burned basis, probably due to oxygenated structures r

  14. Development and Characterization Testing of an Air Pulsation Valve for a Pulse Detonation Engine Supersonic Parametric Inlet Test Section

    NASA Technical Reports Server (NTRS)

    Tornabene, Robert

    2005-01-01

    In pulse detonation engines, the potential exists for gas pulses from the combustor to travel upstream and adversely affect the inlet performance of the engine. In order to determine the effect of these high frequency pulses on the inlet performance, an air pulsation valve was developed to provide air pulses downstream of a supersonic parametric inlet test section. The purpose of this report is to document the design and characterization tests that were performed on a pulsation valve that was tested at the NASA Glenn Research Center 1x1 Supersonic Wind Tunnel (SWT) test facility. The high air flow pulsation valve design philosophy and analyses performed are discussed and characterization test results are presented. The pulsation valve model was devised based on the concept of using a free spinning ball valve driven from a variable speed electric motor to generate air flow pulses at preset frequencies. In order to deliver the proper flow rate, the flow port was contoured to maximize flow rate and minimize pressure drop. To obtain sharp pressure spikes the valve flow port was designed to be as narrow as possible to minimize port dwell time.

  15. Investigation of X24C-2 10-Stage Axial-Flow Compressor. 2; Effect of Inlet-Air Pressure and Temperature of Performance

    NASA Technical Reports Server (NTRS)

    Finger, Harold B.; Schum, Harold J.; Buckner, Howard Jr.

    1947-01-01

    Effect of inlet-air pressure and temperature on the performance of the X24-2 10-Stage Axial-Flow Compressor from the X24C-2 turbojet engine was evaluated. Speeds of 80, 89, and 100 percent of equivalent design speed with inlet-air pressures of 6 and 12 inches of mercury absolute and inlet-air temperaures of approximately 538 degrees, 459 degrees,and 419 degrees R ( 79 degrees, 0 degrees, and minus 40 degrees F). Results were compared with prior investigations.

  16. The induction of water to the inlet air as a means of internal cooling in aircraft-engine cylinders

    NASA Technical Reports Server (NTRS)

    Rothrock, Addison M; Krsek, Alois, Jr; Jones, Anthony W

    1943-01-01

    Report presents the results of investigations conducted on a full-scale air-cooled aircraft-engine cylinder of 202-cubic inch displacement to determine the effects of internal cooling by water induction on the maximum permissible power and output of an internal-combustion engine. For a range of fuel-air and water-fuel ratios, the engine inlet pressure was increased until knock was detected aurally, the power was then decreased 7 percent holding the ratios constant. The data indicated that water was a very effective internal coolant, permitting large increases in engine power as limited by either knock or by cylinder temperatures.

  17. Effect of inlet-air humidity, temperature, pressure, and reference Mach number on the formation of oxides of nitrogen in a gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

    1973-01-01

    Tests were conducted to determine the effect of inlet air humidity on the formation of oxides of nitrogen (NOx) from a gas turbine combustor. Combustor inlet air temperature ranged from 506 K (450 F) to 838 K (1050 F). The tests were primarily run at a constant pressure of 6 atmospheres and reference Mach number of 0.065. The NOx emission index was found to decrease with increasing inlet air humidity at a constant exponential rate: NOx = NOx0e-19H (where H is the humidity and the subscript 0 denotes the value at zero humidity). the emission index increased exponentially with increasing normalized inlet air temperature to the 1.14 power. Additional tests made to determine the effect of pressure and reference Mach number on NOx showed that the NOx emission index varies directly with pressure to the 0.5 power and inversely with reference Mach number.

  18. Modification of Cabinet Fans with Inlet Air Guide Fairings to Improve Performance.

    DTIC Science & Technology

    1983-04-01

    CHAMPAIGN IL W H DOLAN ANLSIFE PR 83 CERL-TR-E-i~i F /G 13/1i N EIND IllIflI2.8 25 36 1111.8 1.4 L16 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF...fan inlet conditions. By observing airflow within the cabinet, a DO ,~~ F 10 EDIIONOF NOV6 ISOSOETEUNCLASS IFIED SACUSSTV CLASSIFICATION OF THIS PAGE...7 F ,.vousA.F i 7$ __. DISCHARGE PLATE CONNECTING FAN WHEEL TO FAN SHAFT. ROTATING FAN WHEEL Fig.,e 1. Double Width, Double Inlet (DWDI) centrifugal

  19. Isokinetic air sampler

    DOEpatents

    Sehmel, George A.

    1979-01-01

    An isokinetic air sampler includes a filter, a holder for the filter, an air pump for drawing air through the filter at a fixed, predetermined rate, an inlet assembly for the sampler having an inlet opening therein of a size such that isokinetic air sampling is obtained at a particular wind speed, a closure for the inlet opening and means for simultaneously opening the closure and turning on the air pump when the wind speed is such that isokinetic air sampling is obtained. A system incorporating a plurality of such samplers provided with air pumps set to draw air through the filter at the same fixed, predetermined rate and having different inlet opening sizes for use at different wind speeds is included within the ambit of the present invention as is a method of sampling air to measure airborne concentrations of particulate pollutants as a function of wind speed.

  20. Modelling the long-term morphological evolution of a coupled open coast, inlet and estuary system to explore climate change impacts

    NASA Astrophysics Data System (ADS)

    van Maanen, Barend; Walkden, Mike; Barnes, John; Nicholls, Robert

    2016-04-01

    Coastal and shoreline management increasingly needs to account for morphological change occurring at decadal to centennial timescales. Critical aspects of geomorphic behaviour at these temporal scales emerge at a system level, such that accounting for the feedbacks between different landform components is of key importance. In this study we develop new methods to simulate the large-scale evolution of a coupled open coast - inlet - estuary system, allowing us to explore the system's response to climate change impacts and management interventions. The system explored here encompasses the Deben estuary (eastern England) and its adjacent shorelines. The estuary itself mainly consists of finer sediments. Sediments throughout the inlet, on the other hand, including the ebb-tidal delta itself, comprise a mixture of gravel and sand. The ebb-tidal shoals and sediment bypassing show broadly cyclic behaviour on a 10 to 30 year timescale. Neighbouring beaches consist of mixed sediment and are partially backed up by sedimentary cliffs, the behaviour of which is potentially influenced by the sediment bypassing at the inlet. In addition, the open coast has undergone major transformations as a result of numerous sea defences which have altered sediment availability and supply. The interlinked behaviour of this system is approached by coupling a new inlet model (MESO_i) with an existing, and recently extended, model for the open coast (SCAPE+). MESOi simulates the evolution at the mouth of the Deben at an aggregated scale, conceptualizing the inlet by different geomorphic features that are characterized mainly by their volume. The behaviour of the inlet shoals is influenced by the estuarine tidal prism, linking estuarine processes with inlet dynamics. SCAPE+ computes the shaping of the shore profile and has proven capable of providing valuable information in terms of decadal evolution and related cliff recession rates. Simulations conducted with this composition of models highlight

  1. Heat transfer to two-phase air/water mixtures flowing in small tubes with inlet disequilibrium

    NASA Technical Reports Server (NTRS)

    Janssen, J. M.; Florschuetz, L. W.; Fiszdon, J. P.

    1986-01-01

    The cooling of gas turbine components was the subject of considerable research. The problem is difficult because the available coolant, compressor bleed air, is itself quite hot and has relatively poor thermophysical properties for a coolant. Injecting liquid water to evaporatively cool the air prior to its contact with the hot components was proposed and studied, particularly as a method of cooling for contingency power applications. Injection of a small quantity of cold liquid water into a relatively hot coolant air stream such that evaporation of the liquid is still in process when the coolant contacts the hot component was studied. No approach was found whereby heat transfer characteristics could be confidently predicted for such a case based solely on prior studies. It was not clear whether disequilibrium between phases at the inlet to the hot component section would improve cooling relative to that obtained where equilibrium was established prior to contact with the hot surface.

  2. Optimal Micro-Vane Flow Control for Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

    2004-01-01

    The purpose of this study on micro-vane secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-vane secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low unit strength" micro-effector arrays. "Low unit strength" micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. Therefore, this report examines optimal micro-vane secondary flow control array designs for compact inlets through a Response Surface Methodology.

  3. Management of Total Pressure Recovery, Distortion and High Cycle Fatigue in Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Baust, Henry D.; Agrell, Johan

    2002-01-01

    It is the purpose of this study to demonstrate the viability and economy of Response Surface Methods (RSM) and Robustness Design Concepts (RDC) to arrive at micro-secondary flow control installation designs that maintain optimal inlet performance over a range of the mission variables. These statistical design concepts were used to investigate the robustness properties of 'low unit strength' micro-effector installations. 'Low unit strength' micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion.

  4. Effect of inlet temperature on the performance of a catalytic reactor. [air pollution control

    NASA Technical Reports Server (NTRS)

    Anderson, D. N.

    1978-01-01

    A 12 cm diameter by 15 cm long catalytic reactor was tested with No. 2 diesel fuel in a combustion test rig at inlet temperatures of 700, 800, 900, and 1000 K. Other test conditions included pressures of 3 and 6 x 10 to the 5th power Pa, reference velocities of 10, 15, and 20 m/s, and adiabatic combustion temperatures in the range 1100 to 1400 K. The combustion efficiency was calculated from measurements of carbon monoxide and unburned hydrocarbon emissions. Nitrogen oxide emissions and reactor pressure drop were also measured. At a reference velocity of 10 m/s, the CO and unburned hydrocarbons emissions, and, therefore, the combustion efficiency, were independent of inlet temperature. At an inlet temperature of 1000 K, they were independent of reference velocity. Nitrogen oxides emissions resulted from conversion of the small amount (135 ppm) of fuel-bound nitrogen in the fuel. Up to 90 percent conversion was observed with no apparent effect of any of the test variables. For typical gas turbine operating conditions, all three pollutants were below levels which would permit the most stringent proposed automotive emissions standards to be met.

  5. Validation Opening Remarks and AIRS-AMST-E Comparisons

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.

    2005-01-01

    Opening remarks to the authors who presented their AIRS validation papers to Journal of Geophysical Research is presented. A general overview of AIRS-AMST-E total water vapor comparisons is also presented.

  6. Open air refuse burning video: Proton Dan the science man explores open air refuse burning

    SciTech Connect

    Eastburn, M.D.; Sipple, J.L.; Deramo, A.R.

    1999-07-01

    The goal of this video is to educate school children to the potential hazards of open air trash burning; to demonstrate alternative ways to dispose of trash; and to motivate students to take action to change the behavior of their parents with regard to trash burning. The burning of household trash, although illegal, is still a common practice in rural areas of Delaware. Enforcement has been difficult because the practice is often performed at night and is done across a wide rural area that is difficult to patrol on a continuing basis. The prohibition on trash burning (revised Regulation 13 of The Delaware Code of Regulations Governing The Control of Air Pollution) has been in effect since 1968, but the public has been slow to comply because trash burning has been practiced for many generations and because much of the public is unaware of the environmental impacts and/or the human health risks. This video may be valuable for other States to use as a public outreach tool regarding their problems with open air refuse burning. The focus of the video is a 7th grade science class is given various assignments relating to Earth Day and preservation of natural resources. Two children in particular are given the assignment to research and report on the hazards of open air trash burning and are asked to investigate alternative ways to dispose of refuse. Upon brainstorming how to find information on the topic, the kids decide to contact the host of a popular children's science show on broadcast television named Proton Dan the Science Man (a fictitious character and show based on Bill Nye the Science Guy). The host then invites the kids to the studio where he films his show and takes them through the topic. The TV host character takes the children to several external locations like a landfill, recycling centers, etc..

  7. Sediment, water column, and open-channel denitrification in rivers measured using membrane-inlet mass spectrometry

    NASA Astrophysics Data System (ADS)

    Reisinger, Alexander J.; Tank, Jennifer L.; Hoellein, Timothy J.; Hall, Robert O.

    2016-05-01

    Riverine biogeochemical processes are understudied relative to headwaters, and reach-scale processes in rivers reflect both the water column and sediment. Denitrification in streams is difficult to measure, and is often assumed to occur only in sediment, but the water column is potentially important in rivers. Dissolved nitrogen (N) gas flux (as dinitrogen (N2)) and open-channel N2 exchange methods avoid many of the artificial conditions and expenses of common denitrification methods like acetylene block and 15N-tracer techniques. We used membrane-inlet mass spectrometry and microcosm incubations to quantify net N2 and oxygen flux from the sediment and water column of five Midwestern rivers spanning a land use gradient. Sediment and water column denitrification ranged from below detection to 1.8 mg N m-2 h-1 and from below detection to 4.9 mg N m-2 h-1, respectively. Water column activity was variable across rivers, accounting for 0-85% of combined microcosm denitrification and 39-85% of combined microcosm respiration. Finally, we estimated reach-scale denitrification at one Midwestern river using a diel, open-channel N2 exchange approach based on reach-scale metabolism methods, providing an integrative estimate of riverine denitrification. Reach-scale denitrification was 8.8 mg N m-2 h-1 (95% credible interval: 7.8-9.7 mg N m-2 h-1), higher than combined sediment and water column microcosm estimates from the same river (4.3 mg N m-2 h-1) and other estimates of reach-scale denitrification from streams. Our denitrification estimates, which span habitats and spatial scales, suggest that rivers can remove N via denitrification at equivalent or higher rates than headwater streams.

  8. An inlet air washer/chiller system for combined cycle planet repowering

    SciTech Connect

    Sengupta, U.; Soroka, G. )

    1989-01-01

    A conditioning method to achieve increased output at any relative humidity condition is an air washer and absorption chiller arrangement. At elevated temperatures and low humidity, the air washer operates as an evaporative cooler without the chiller in operation. In this mode, the air washer will give similar results as a media type evaporative cooler at a fraction of the pressure loss. In the air washer plus chiller operating mode the chiller maintains cooling effectiveness of the air washer during periods of high relative humidity. This makes such a system very appropriate anywhere relative humidity is high. Many combined cycle plants utilize supplemental firing of the heat recovery steam generators to offset the loss of gas turbine power at high ambient temperatures. This paper shows that in contrast to supplementary firing, the combination air washer/chiller system can generate power more efficiently and at lower cost.

  9. Optimal Micro-Jet Flow Control for Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

    2004-01-01

    The purpose of this study on micro-jet secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-jet secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low mass" micro-jet array designs. The term "low mass" micro-jet may refers to fluidic jets with total (integrated) mass flow ratios between 0.10 and 1.0 percent of the engine face mass flow. Therefore, this report examines optimal micro-jet array designs for compact inlets through a Response Surface Methodology.

  10. Integration of air separation membrane and coalescing filter for use on an inlet air system of an engine

    DOEpatents

    Moncelle, Michael E.

    2003-01-01

    An intake air separation system suitable for combustion air of an internal combustion engine. An air separation device of the system includes a plurality of fibers, each fiber having a tube with a permeation barrier layer on the outer surface thereof and a coalescing layer on the inner surface thereof, to restrict fluid droplets from contacting the permeation barrier layer.

  11. EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN BURNING

    EPA Science Inventory

    A detailed literature search was performed to collect and collate available data reporting emissions of toxic organic substances into the air from open burning sources. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic c...

  12. Effect of Gas/Steam Turbine Inlet Temperatures on Combined Cycle Having Air Transpiration Cooled Gas Turbine

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Singh, O.

    2012-10-01

    Worldwide efforts are being made for further improving the gas/steam combined cycle performance by having better blade cooling technology in topping cycle and enhanced heat recovery in bottoming cycle. The scope of improvement is possible through turbines having higher turbine inlet temperatures (TITs) of both gas turbine and steam turbine. Literature review shows that a combined cycle with transpiration cooled gas turbine has not been analyzed with varying gas/steam TITs. In view of above the present study has been undertaken for thermodynamic study of gas/steam combined cycle with respect to variation in TIT in both topping and bottoming cycles, for air transpiration cooled gas turbine. The performance of combined cycle with dual pressure heat recovery steam generator has been evaluated for different cycle pressure ratios (CPRs) varying from 11 to 23 and the selection diagrams presented for TIT varying from 1,600 to 1,900 K. Both the cycle efficiency and specific work increase with TIT for each pressure ratio. For each TIT there exists an optimum pressure ratio for cycle efficiency and specific work. For the CPR of 23 the best cycle performance is seen at a TIT of 1,900 K for maximum steam temperature of 570 °C, which gives the cycle efficiency of 60.9 % with net specific work of 909 kJ/kg.

  13. Analytical evaluation of effect of equivalence ratio inlet-air temperature and combustion pressure on performance of several possible ram-jet fuels

    NASA Technical Reports Server (NTRS)

    Tower, Leonard K; Gammon, Benson E

    1953-01-01

    The results of an analytical investigation of the theoretical air specific impulse performance and adiabatic combustion temperatures of several possible ram-jet fuels over a range of equivalence ratios, inlet-air temperatures, and combustion pressures, is presented herein. The fuels include octane-1, 50-percent-magnesium slurry, boron, pentaborane, diborane, hydrogen, carbon, and aluminum. Thermal effects from high combustion temperatures were found to effect considerably the combustion performance of all the fuels. An increase in combustion pressure was beneficial to air specific impulse at high combustion temperatures. The use of these theoretical data in engine operation and in the evaluation of experimental data is described.

  14. Turbulence Effects on Open Air Multipaths.

    DTIC Science & Technology

    1981-05-01

    RECIPIENT- CATALOG NJM-.rl ASL-TR-0086 T-,’ 101 )- , . 4. TITLE (id Subttle) S. TT!E O F REPORT 6 tiEre)1, UCVERED TURBULENCE LFFECTS ON OPEN R D Final...was comparable in terms of beam epaiO.or3. litter, and wander to tn f]3riJation experienced in a sealed levacrab> absoroDon c-11. Th-i wa’ indeed...Measurements," Rev Sci Instrum, 50:86 ’ D . L. Fried, 1966, "Limiting Resolution Looking Down Through the Atmosphere," J Opt Soc Am, 56:1380 8 POWER METER

  15. Preliminary Investigation of a Conical Spike Inlet in Combination with a Vertical-wedge Auxiliary Inlet at Mach Number 1.9

    NASA Technical Reports Server (NTRS)

    Beke, Andrew; Allen, John L; Williams, Thomas

    1955-01-01

    Pressure-recovery characteristics of a nacelle-type-spike inlet in combination with a vertical-wedge auxiliary scoop are presented for a free-stream Mach number of 1.9 at zero angle of attack. The auxiliary scoop provided 17 percent additional air flow with a drop in critical pressure recovery from 0.86 to 0.81. However, in terms of inlet-engine matching, the pressure recovery of the undersized spike inlet operating at a specified corrected air flow increased with the scoop open, for example, from 0.69 to 0.81.

  16. Changes in Clinical Symptoms, Functions, and the Median Nerve Cross-Sectional Area at the Carpal Tunnel Inlet after Open Carpal Tunnel Release

    PubMed Central

    Koh, Young-Do; Kim, Jong Oh; Choi, Shin Woo

    2016-01-01

    Background The aim of this study was to investigate the relationship between clinical symptoms and cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet before and after open carpal tunnel release (CTR). Methods Thirty-two patients (53 hands) that underwent open CTR for idiopathic carpal tunnel syndrome were prospectively enrolled. Median nerve CSA at the carpal tunnel inlet was measured preoperatively and at 2 and 12 weeks after CTR by high resolution ultrasonography. The Boston carpal tunnel questionnaire (BCTQ) was also completed at these times. Results BCTQ symptom (BCTQ-S) score was significantly improved at 2 weeks postoperatively, but BCTQ function (BCTQ-F) score and CSA were significantly improved at 12 weeks postoperatively. Preoperative CSA was significantly correlated with preoperative BCTQ-S and BCTQ-F scores but was not significantly correlated with postoperative BCTQ scores or postoperative changes in BCTQ scores. Postoperative median nerve CSA was not significantly correlated with postoperative BCTQ-S or BCTQ-F scores, and postoperative changes in median nerve CSA were not significantly correlated with postoperative changes in BCTQ-S or BCTQ-F scores. Conclusions The study shows clinical symptoms resolve rapidly after open CTR, but median nerve swelling and clinical function take several months to recover. In addition, preoperative median nerve swelling might predict preoperative severities of clinical symptoms and functional disabilities. However, postoperative reductions in median nerve swelling were not found to reflect postoperative reductions in clinical symptoms or functional disabilities. PMID:27583113

  17. Investigation at supersonic and subsonic Mach numbers of auxiliary inlets supplying secondary air flow to ejector exhaust nozzles

    NASA Technical Reports Server (NTRS)

    Hearth, Donald P; Cubbison, Robert W

    1956-01-01

    The results indicated increases in auxiliary-inlet pressure recovery with increases in scoop height relative to the boundary-layer thickness. The pressure recovery increased at about the same rate as theoretically predicted for an inlet in a boundary layer having a one-seventh power profile, but was only about 0.68 to 0.75 of the theoretically obtainable values. Under some operating conditions, flow from the primary jet was exhausted through the auxiliary inlet. This phenomenon could be predicted from the ejector pumping characteristics.

  18. The effect of different inlet conditions of air in a rectangular channel on convection heat transfer: Turbulence flow

    SciTech Connect

    Kurtbas, Irfan

    2008-10-15

    Theoretical and empirical correlations for duct flow are given for hydrodynamically and thermally developed flow in most of previous studies. However, this is commonly not a realistic inlet configuration for heat exchanger, in which coolant flow generally turns through a serpentine shaped passage before entering heat sinks. Accordingly, an experimental investigation was carried out to determine average heat transfer coefficients in uniformly heated rectangular channel with 45 and 90 turned flow, and with wall mounted a baffle. The channel was heated through bottom side with the baffle. In present work, a detailed study was conducted for three different height of entry channel (named as the ratio of the height of entry channel to the height of test section (anti H{sub c}=h{sub c}/H)) by varying Reynolds number (Re{sub Dh}). Another variable parameter was the ratio of the baffle height to the channel height (anti H{sub b}=h{sub b}/H). Only one baffle was attached on the bottom (heating) surface. The experimental procedure was validated by comparing the data for the straight channel with no baffle. Reynolds number (Re{sub Dh}) was varied from 2800 to 30,000, so the flow was considered as only turbulent regime. All experiments were conduced with air accordingly; Prandtl number (Pr) was approximately fixed at 0.71. The results showed that average Nusselt number for {theta}=45 and {theta}=90 were 9% and 30% higher, respectively, than that of the straight channel without baffle. Likewise, the pressure drop increased up to 4.4 to 5.3 times compare to the straight channel. (author)

  19. Attic inlet technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rising fuel costs have driven development of alternative heat sources for poultry growers. Attic inlets are employed to pre-heat incoming ventilation air to reduce fuel usage. Attic temperatures are at least 10 °F warmer than the outside temperature at least 80% of the time and offers a source of...

  20. Experimental Investigation of an Air-Cooled Turbine Operating in a Turbojet Engine at Turbine Inlet Temperatures up to 2500 F

    NASA Technical Reports Server (NTRS)

    Cochran, Reeves P.; Dengler, Robert P.

    1961-01-01

    An experimental investigation was made of an air-cooled turbine at average turbine inlet temperatures up to 2500 F. A modified production-model 12-stage axial-flow-compressor turbojet engine operating in a static sea-level stand was used as the test vehicle. The modifications to the engine consisted of the substitution of special combustor and turbine assemblies and double-walled exhaust ducting for the standard parts of the engine. All of these special parts were air-cooled to withstand the high operating temperatures of the investigation. The air-cooled turbine stator and rotor blades were of the corrugated-insert type. Leading-edge tip caps were installed on the rotor blades to improve leading-edge cooling by diverting the discharge of coolant to regions of lower gas pressure toward the trailing edge of the blade tip. Caps varying in length from 0.15- to 0.55-chord length were used in an attempt to determine the optimum cap length for this blade. The engine was operated over a range of average turbine inlet temperatures from about 1600 to about 2500 F, and a range of average coolant-flow ratios of 0.012 to 0.065. Temperatures of the air-cooled turbine rotor blades were measured at all test conditions by the use of thermocouples and temperature-indicating paints. The results of the investigation indicated that this type of blade is feasible for operation in turbojet engines at the average turbine inlet temperatures and stress levels tested(maximums of 2500 F and 24,000 psi, respectively). An average one-third-span blade temperature of 1300 F could be maintained on 0.35-chord tip cap blades with an average coolant-flow ratio of about 0.022 when the average turbine inlet temperature was 2500 F and cooling-air temperature was about 260 F. All of the leading-edge tip cap lengths improved the cooling of the leading-edge region of the blades, particularly at low average coolant-flow ratios. At high gas temperatures, such parts as the turbine stator and the combustor

  1. Oscillations of a sessile droplet in open air

    NASA Astrophysics Data System (ADS)

    Korenchenko, A. E.; Beskachko, V. P.

    2013-11-01

    The open system consisting of a sessile drop, a neutral gas, and a substrate is analyzed by numerical methods. The mode with constant contact angle is considered. The model takes into account evaporation from drop surface, free and forced convection in gas, buoyancy, and Marangoni effect in the liquid phase. It was established that every considered mechanical and thermodynamical disturbance of the system leads to the drop surface oscillations, and thus a drop in an open air oscillates almost inevitably. The displacement of the liquid-gas interface due to oscillations is analyzed in terms of its impact on the accuracy of measurement of the surface tension by sessile drop method.

  2. Oscillations of a sessile droplet in open air

    SciTech Connect

    Korenchenko, A. E.; Beskachko, V. P.

    2013-11-15

    The open system consisting of a sessile drop, a neutral gas, and a substrate is analyzed by numerical methods. The mode with constant contact angle is considered. The model takes into account evaporation from drop surface, free and forced convection in gas, buoyancy, and Marangoni effect in the liquid phase. It was established that every considered mechanical and thermodynamical disturbance of the system leads to the drop surface oscillations, and thus a drop in an open air oscillates almost inevitably. The displacement of the liquid-gas interface due to oscillations is analyzed in terms of its impact on the accuracy of measurement of the surface tension by sessile drop method.

  3. Numerical Analysis of Thermal Comfort at Open Air Spaces

    NASA Astrophysics Data System (ADS)

    Papakonstantinou, K.; Belias, C.; Pantos-Kikkos, S.; Assana, A.

    2008-09-01

    The present paper refers to the numerical simulation of air velocity at open air spaces and the conducting thermal comfort after the evaluation of the examined space using CFD methods, taking into account bioclimatic principles at the architectural design. More specially, the paper draws attention to the physical procedures governing air movement at an open environment area in Athens (urban park), named "Attiko Alsos," trying to form them in such way that will lead to the thermal comfort of the area's visitors. The study presents a mathematical model, implemented in a general computer code that can provide detailed information on velocity, prevailing in three-dimensional spaces of any geometrical complexity. Turbulent flow is simulated and buoyancy effects are taken into account. This modelling procedure is intended to contribute to the effort towards designing open areas, such as parks, squares or outdoor building environments, using thermal comfort criteria at the bioclimatic design. A computer model of this kind will provide the architects or the environmental engineers with powerful and economical means of evaluating alternative spaces' designs.

  4. The effects of opening an artificial tidal inlet on hydrography and estuarine macrofauna in Corpus Christi, Texas.

    PubMed

    Palmer, Terence A; Montagna, Paul A; Kalke, Richard D

    2013-07-01

    Packery Channel is part of a complex of storm washover channels which, before 1912, have opened intermittently, linking the Laguna Madre and Corpus Christi Bay, Texas with the Gulf of Mexico. On 21 July 2005, with the assistance of Hurricane Emily, Packery Channel was prematurely opened to the Gulf of Mexico, months before construction of a dredged channel was scheduled to be completed. A before-versus-after, control-versus-impact (BACI) design was used to assess the effects of reopening Packery Channel on water quality and estuarine macrofauna in Mollie Beattie Coastal Habitat Community (MBCHC), Corpus Christi Bay. Two deep (approximately 1 m below m.s.l.) and two shallow (approximately 0.2 m below m.s.l.) stations were sampled monthly for physical and biological characteristics at both control and impact sites between November 2003 and March 2009. The opening of Packery Channel created a unique situation where salinities decreased after the channel opening by ameliorating hypersalinity in Laguna Madre rather than increasing salinities as would occur in most estuaries worldwide. Salinity also fluctuated in a diurnal pattern after the opening of Packery Channel. Apart from salinity, Packery Channel has caused little hydrographic change in MBCHC since opening in July 2005. There was little effect on the macrofaunal community composition. There was a greater difference in community composition between deep and shallow stations than between either before and after or control and impact sites. There have been no significant changes in abundance, biomass, or N1 diversity caused by the opening of Packery Channel.

  5. Inlet/Body Integration Preliminary Design for Supersonic Air-Breathing Missiles Using Automated Multi-Discilinary Optimization

    DTIC Science & Technology

    2000-06-01

    configuration, 33 ometry necessitate sophisticated numerical codes rameters to be d fine theigura tio and refined spatial discretizations which are...get there. The development strategy the exit location of the inlet subsonic diffuser is followed by Aerospatiale Matra Missiles and Rut- fixed. Second...approxi- Parameter Name Value mate 2- D /3- D geometrical models and low accu- 1 Missile diameter (caliber) 1 D racy physical analysis models. 2 Base diameter

  6. Inlet nozzle assembly

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Knight, R.C.; Precechtel, D.R.; Smith, B.G.

    1985-09-09

    An inlet nozzle assembly for directing coolant into the duct tube of a fuel assembly attached thereto. The nozzle assembly includes a shell for housing separable components including an orifice plate assembly, a neutron shield block, a neutron shield plug, and a diffuser block. The orifice plate assembly includes a plurality of stacked plates of differently configurated and sized openings for directing coolant therethrough in a predesigned flow pattern.

  7. Two-dimensional symmetrical inlets with external compression

    NASA Technical Reports Server (NTRS)

    Ruden, P

    1950-01-01

    The purpose of inlets like, for instance, those of air-cooled radiators and scoops is to take a certain air quantity out of the free stream and to partly convert the free-stream velocity into pressure. In the extreme case this pressure conversion may occur either entirely in the interior of the inlet (inlet with internal compression) or entirely in the free stream ahead of the inlet (inlet with external compression). In this report a theory for two-dimensional inlets with external compression is developed and illustrated by numerical examples. Intermediary forms between inlets with internal and external compression which can be derived from the latter are briefly discussed.

  8. A Computational and Experimental Study of Coflow Laminar Methane/Air Diffusion Flames: Effects of Fuel Dilution, Inlet Velocity, and Gravity

    NASA Technical Reports Server (NTRS)

    Cao, S.; Ma, B.; Bennett, B. A. V.; Giassi, D.; Stocker, D. P.; Takahashi, F.; Long, M. B.; Smooke, M. D.

    2014-01-01

    The influences of fuel dilution, inlet velocity, and gravity on the shape and structure of laminar coflow CH4-air diffusion flames were investigated computationally and experimentally. A series of nitrogen-diluted flames measured in the Structure and Liftoff in Combustion Experiment (SLICE) on board the International Space Station was assessed numerically under microgravity (mu g) and normal gravity (1g) conditions with CH4 mole fraction ranging from 0.4 to 1.0 and average inlet velocity ranging from 23 to 90 cm/s. Computationally, the MC-Smooth vorticity-velocity formulation was employed to describe the reactive gaseous mixture, and soot evolution was modeled by sectional aerosol equations. The governing equations and boundary conditions were discretized on a two-dimensional computational domain by finite differences, and the resulting set of fully coupled, strongly nonlinear equations was solved simultaneously at all points using a damped, modified Newton's method. Experimentally, flame shape and soot temperature were determined by flame emission images recorded by a digital color camera. Very good agreement between computation and measurement was obtained, and the conclusions were as follows. (1) Buoyant and nonbuoyant luminous flame lengths are proportional to the mass flow rate of the fuel mixture; computed and measured nonbuoyant flames are noticeably longer than their 1g counterparts; the effect of fuel dilution on flame shape (i.e., flame length and flame radius) is negligible when the flame shape is normalized by the methane flow rate. (2) Buoyancy-induced reduction of the flame radius through radially inward convection near the flame front is demonstrated. (3) Buoyant and nonbuoyant flame structure is mainly controlled by the fuel mass flow rate, and the effects from fuel dilution and inlet velocity are secondary.

  9. Surface charge accumulation of particles containing radionuclides in open air.

    PubMed

    Kim, Yong-ha; Yiacoumi, Sotira; Tsouris, Costas

    2015-05-01

    Radioactivity can induce charge accumulation on radioactive particles. However, electrostatic interactions caused by radioactivity are typically neglected in transport modeling of radioactive plumes because it is assumed that ionizing radiation leads to charge neutralization. The assumption that electrostatic interactions caused by radioactivity are negligible is evaluated here by examining charge accumulation and neutralization on particles containing radionuclides in open air. A charge-balance model is employed to predict charge accumulation on radioactive particles. It is shown that particles containing short-lived radionuclides can be charged with multiple elementary charges through radioactive decay. The presence of radioactive particles can significantly modify the particle charge distribution in open air and yield an asymmetric bimodal charge distribution, suggesting that strong electrostatic particle interactions may occur during short- and long-range transport of radioactive particles. Possible effects of transported radioactive particles on electrical properties of the local atmosphere are reported. The study offers insight into transport characteristics of airborne radionuclides. Results are useful in atmospheric transport modeling of radioactive plumes.

  10. Surface charge accumulation of particles containing radionuclides in open air

    SciTech Connect

    Kim, Yong-ha; Yiacoumi, Sotira; Tsouris, Costas

    2015-05-01

    Radioactivity can induce charge accumulation on radioactive particles. But, electrostatic interactions caused by radioactivity are typically neglected in transport modeling of radioactive plumes because it is assumed that ionizing radiation leads to charge neutralization. The assumption that electrostatic interactions caused by radioactivity are negligible is evaluated here by examining charge accumulation and neutralization on particles containing radionuclides in open air. Moreover, a charge-balance model is employed to predict charge accumulation on radioactive particles. It is shown that particles containing short-lived radionuclides can be charged with multiple elementary charges through radioactive decay. The presence of radioactive particles can significantly modify the particle charge distribution in open air and yield an asymmetric bimodal charge distribution, suggesting that strong electrostatic particle interactions may occur during short- and long-range transport of radioactive particles. Possible effects of transported radioactive particles on electrical properties of the local atmosphere are reported. Our study offers insight into transport characteristics of airborne radionuclides. Results are useful in atmospheric transport modeling of radioactive plumes.

  11. Surface charge accumulation of particles containing radionuclides in open air

    DOE PAGES

    Kim, Yong-ha; Yiacoumi, Sotira; Tsouris, Costas

    2015-05-01

    Radioactivity can induce charge accumulation on radioactive particles. But, electrostatic interactions caused by radioactivity are typically neglected in transport modeling of radioactive plumes because it is assumed that ionizing radiation leads to charge neutralization. The assumption that electrostatic interactions caused by radioactivity are negligible is evaluated here by examining charge accumulation and neutralization on particles containing radionuclides in open air. Moreover, a charge-balance model is employed to predict charge accumulation on radioactive particles. It is shown that particles containing short-lived radionuclides can be charged with multiple elementary charges through radioactive decay. The presence of radioactive particles can significantly modify themore » particle charge distribution in open air and yield an asymmetric bimodal charge distribution, suggesting that strong electrostatic particle interactions may occur during short- and long-range transport of radioactive particles. Possible effects of transported radioactive particles on electrical properties of the local atmosphere are reported. Our study offers insight into transport characteristics of airborne radionuclides. Results are useful in atmospheric transport modeling of radioactive plumes.« less

  12. Open air demolition of facilities highly contaminated with plutonium

    SciTech Connect

    Lloyd, E.R.; Lackey, M.B.; Stevens, J.M.; Zinsli, L.C.

    2007-07-01

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than 'hands on' techniques. (authors)

  13. OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

    SciTech Connect

    LLOYD, E.R.

    2007-05-31

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques.

  14. CFD Analysis to Study Effect of Circular Vortex Generator Placed in Inlet Section to Investigate Heat Transfer Aspects of Solar Air Heater

    PubMed Central

    Gawande, Vipin B.; Dhoble, A. S.; Zodpe, D. B.

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate. PMID:25254251

  15. CFD analysis to study effect of circular vortex generator placed in inlet section to investigate heat transfer aspects of solar air heater.

    PubMed

    Gawande, Vipin B; Dhoble, A S; Zodpe, D B

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate.

  16. Open-Air Biowarfare Testing and the Evolution of Values

    PubMed Central

    2016-01-01

    The United States and the United Kingdom ended outdoor biological warfare testing in populated areas nearly half a century ago. Yet, the conduct, health effects, and propriety of those tests remain controversial. The varied views reflect the limits of currently available test information and evolving societal values on research involving human subjects. Western political culture has changed since the early days of the American and British testing programs. People have become less reluctant to question authority, and institutional review boards must now pre-approve research involving human subjects. Further, the heightened stringency of laboratory containment has accentuated the safety gap between a confined test space and one without physical boundaries. All this makes it less likely that masses of people would again be unwittingly subjected to secret open-air biological warfare tests. PMID:27564984

  17. Experimental and numerical study of open-air active cooling

    NASA Astrophysics Data System (ADS)

    Al-Fifi, Salman Amsari

    The topic of my thesis is Experimental and Numerical Study of Open Air Active Cooling. The present research is intended to investigate experimentally and Numerically the effectiveness of cooling large open areas like stadiums, shopping malls, national gardens, amusement parks, zoos, transportation facilities and government facilities or even in buildings outdoor gardens and patios. Our cooling systems are simple cooling fans with different diameters and a mist system. This type of cooling systems has been chosen among the others to guarantee less energy consumption, which will make it the most favorable and applicable for cooling such places mentioned above. In the experiments, the main focus is to study the temperature domain as a function of different fan diameters aerodynamically similar in different heights till we come up with an empirical relationship that can determine the temperature domain for different fan diameters and for different heights of these fans. The experimental part has two stages. The first stage is devoted to investigate the maximum range of airspeed and profile for three different fan diameters and for different heights without mist, while the second stage is devoted to investigate the maximum range of temperature and profile for the three different diameter fans and for different heights with mist. The computational study is devoted to built an experimentally verified mathematical model to be used in the design and optimization of water mist cooling systems, and to compare the mathematical results to the experimental results and to get an insight of how to apply such evaporative mist cooling for different places for different conditions. In this study, numerical solution is presented based on experimental conditions, such dry bulb temperature, wet bulb temperature, relative humidity, operating pressure and fan airspeed. In the computational study, all experimental conditions are kept the same for the three fans except the fan airspeed

  18. Wind tunnel tests of a zero length, slotted-lip engine air inlet for a fixed nacelle V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Woollett, R. R.; Beck, W. E., Jr.; Glasgow, E. R.

    1982-01-01

    Zero length, slotted lip inlet performance and associated fan blade stresses were determined during model tests using a 20 inch diameter fan simulator in the NASA-LeRC 9 by 15 foot low speed wind tunnel. The model configuration variables consisted of inlet contraction ratio, slot width, circumferential extent of slot fillers, and length of a constant area section between the inlet throat and fan face. The inlet performance was dependent on slot gap width and relatively independent of inlet throat/fan face spacer length and slot flow blockage created by 90 degree slot fillers. Optimum performance was obtained at a slot gap width of 0.36 inch. The zero length, slotted lip inlet satisfied all critical low speed inlet operating requirements for fixed horizontal nacelles subsonic V/STOL aircraft.

  19. Low flight speed acoustic results for a supersonic inlet with auxiliary inlet doors

    NASA Technical Reports Server (NTRS)

    Woodward, R. P.; Glaser, F. W.; Lucas, J. G.

    1982-01-01

    A model supersonic inlet with auxiliary inlet doors and bounday layer bleeds was acoustically tested in simulated low speed flight up to Mach 0.2 in the NASA Lewis 9x15 Anechoic Wind Tunnel and statically in the NASA Lewis Anechoic Chamber. A JT8D refan model was used as the noise source. Data were also taken for a CTOL inlet and for an annular inlet with simulated centerbody support struts. Inlet operation with open auxiliary doors increased the blade passage tone by about 10 dB relative to the closed door configuration although noise radiation was primarily through the main inlet rather than the doors. Numerous strong spikes in the noise spectra were associated with the bleed system, and were strongly affected by the centerbody location. The supersonic inlet appeared to suppress multiple pure tone (MPT) generation at the fan source. Inlet length and the presence of support struts were shown not to cause this MPT suppression.

  20. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Gauging devices, top loading and unloading devices... DOT-111AW and 115AW) § 179.200-16 Gauging devices, top loading and unloading devices, venting and air...). In no case shall the wall thickness be less than that specified in § 179.201-1. (f) When top...

  1. Dual-Comb Spectroscopy in the Open Air

    NASA Astrophysics Data System (ADS)

    Rieker, Greg B.; Klose, Andrew; Diddams, Scott; Coddington, Ian; Giorgetta, Fabrizio; Sinclair, Laura; Baumann, Esther; Truong, Gar-Wing; Ycas, Gabriel; Swann, William C.; Newbury, Nathan R.

    2015-06-01

    Dual-comb spectroscopy is arguably the natural successor to FTIR. Based on the interference between two frequency combs, this technique can record broadband spectra with a resolution better than 0.0003 wn. Like FTIR, dual-comb spectroscopy measures an entire spectrum simultaneously, allowing for suppression of systematic errors related to temporal dynamics of the sample. Unlike FTIR it records the entire spectrum with virtually no instrument lineshape or error in the frequency axis. The lack of moving parts in dual-comb spectroscopy means that spectra can be recorded in milliseconds to microseconds with the desired signal-to-noise being the only real constrain on the minimum recording time. Finally the high spacial beam quality of the frequency combs allows for increased sensitivity through long interaction paths either in free-space, multi-pass cells or enhancement cavities. This talk will explore the recent use of dual-comb spectroscopy in the near-infrared to measure atmospheric carbon dioxide, methane and water concentrations over a 2-km outdoor open-air path. Due to many of the strengths just mentioned, precisions of <1 ppm for CO_2 and <3 ppb for CH_4 in 5 min are achieved making this system very attractive for carbon monitoring at length scales relevant to carbon transport models. Additionally this presentation will address recent work on robust, compact, and portable dual-comb spectrometers as well as dual-comb spectroscopy further into the IR.

  2. Inlet Geomorphology Evolution

    DTIC Science & Technology

    2015-04-01

    APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Inlet Geomorphology Evolution 5a. CONTRACT NUMBER 5b...Std Z39-18 Coastal Inlets Research Program Inlet Geomorphology Evolution The Inlet Geomorphology Evolution work unit of the CIRP evaluates

  3. Inlet Engineering Toolbox

    DTIC Science & Technology

    2014-10-31

    ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS,39180... Coastal Inlets Research Program Inlet Engineering Toolbox The Inlet Engineering Toolbox (IET) Work Unit develops desktop PC and web-based tools to...aid in studies of the consequences of engineering actions at coastal inlets and adjacent beaches. District scientists and engineers need rapid

  4. Improving microbial air quality in air-conditioned mass transport buses by opening the bus exhaust ventilation fans.

    PubMed

    Luksamijarulkul, Pipat; Arunchai, Nongphon; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan

    2005-07-01

    The air quality in air-conditioned mass transport buses may affect bus drivers' health. In-bus air quality improvement with the voluntary participation of bus drivers by opening the exhaust ventilation fans in the bus was implemented in the Seventh Bus Zone of Bangkok Mass Transit Authority. Four bus numbers, including bus numbers 16, 63, 67 and 166, were randomly selected to investigate microbial air quality and to observe the effect of opening the exhaust ventilation fans in the bus. With each bus number, 9 to 10 air-conditioned buses (total, 39 air-conditioned buses) were included. In-bus air samples were collected at 5 points in each studied bus using the Millipore Air Tester. A total of 195 air samples were cultured for bacterial and fungal counts. The results reveal that the exhaust ventilation fans of 17 air-conditioned buses (43.6%) were opened to ventilate in-bus air during the cycle of the bus route. The means +/- SD of bacterial counts and fungal counts in the studied buses with opened exhaust ventilation fans (83.8 +/- 70.7 and 38.0 +/- 42.8 cfu/m3) were significantly lower than those in the studied buses without opened exhaust ventilation fans (199.6 +/- 138.8 and 294.1 +/- 178.7 cfu/m3), p < 0.0005. All the air samples collected from the studied buses with opened exhaust ventilation fans were at acceptable levels (< 500 cfu/m3) compared with 4.6% of the air samples collected from the studied buses without opened exhaust ventilation fans, which had high levels (> 500 cfu/m3). Of the studied buses with opened exhaust ventilation fans (17 buses), the bacterial and fungal counts after opening the exhaust ventilation fans (68.3 +/- 33.8 and 28.3 +/- 19.3 cfu/m3) were significantly lower than those before opening the exhaust ventilation fans (158.3 +/- 116.9 and 85.3 +/- 71.2 cfu/m3), p < 0.005.

  5. Coastal Inlets Research Program

    DTIC Science & Technology

    2015-02-09

    FEB 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Coastal Inlets Research Program 5a. CONTRACT NUMBER...S) AND ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS...CIRP.aspx Coastal Inlets Research Program The Coastal Inlets Research Program (CIRP) is a R&D Program funded through the Operations & Maintenance

  6. Inlet Housing for a Partial-Admission Turbine

    NASA Technical Reports Server (NTRS)

    Moye, Ralph; Myers, William; Baker, Kevin

    2004-01-01

    An inlet housing for a partial-admission turbine has been designed to cause the inlet airflow to make a smooth transition from an open circular inlet to an inlet slot. The smooth flow is required for purposes of measuring inlet flow characteristics and maximizing the efficiency of the turbine. A partial-admission turbine is a turbine in which the inlet slot occupies less than a complete circle around the rotor axis. In this case, the inlet slot occupies a 90 arc. The present special inlet-housing design is needed because the "bull nose" shape of a conventional turbine inlet housing fails to provide the required smooth transition in a partial-admission configuration and thereby gives rise to a loss of turbine efficiency and inaccuracies in inlet flow measurements. Upon entering the inlet housing through the circular opening, the flow encounters a "tongue"-shaped passageway, which serves as a ramp that diverts the flow to the first of two straight passages. This first passageway occupies a 90 arc and has a length equal to two passage heights. Instrumentation rakes for measuring the characteristics of the inlet flow are installed in this passageway. Just past the first straight passageway is the second one, which is narrower and leads to the 90 turbine inlet slot. This passageway is used to smooth the flow immediately prior to its passage through the turbine inlet slot. The length of this second passageway equals the length of the chord of a turbine vane. The inlet housing incorporates small ports for measuring static pressures at various locations of the flow, and incorporates bosses for the installation of the instrumentation rakes. The inlet housing also includes a flange at its inlet end for attachment to a circular inlet duct and a flange at its outlet end for attachment to the outer casing of the turbine.

  7. Wave and Wind Effects on Inlet Circulation

    NASA Astrophysics Data System (ADS)

    Raubenheimer, B.; Wargula, A.; Orescanin, M. M.; Hopkins, J.; Elgar, S.

    2014-12-01

    Observations and numerical simulations of the water circulation and morphological change in two separate, well-mixed inlets will be compared with each other. Tides, winds, waves, and currents were measured from May 1 to 28, 2012 in and near New River Inlet, NC. Offshore significant wave heights were 0 to 3 m, and wind speeds ranged from 0 to 16 m/s. The long, narrow inlet is about 1000 m wide where it opens onto the ebb shoal, narrows to 100 m wide about 1000 m inland, and connects to the Intracoastal Waterway (which connects to additional ocean inlets about 12 and 36 km north and south, respectively) about 3000 m inland. Tides in the inlet are progressive and inlet flows are in phase with water depths. Measurements also were collected during the summers of 2011-2014, including during Hurricanes Irene and Sandy (offshore significant wave heights > 5 m and winds > 15 m/s), in Katama Bay, MA, which connects to Vineyard Sound via Edgartown Channel and to the Atlantic Ocean via Katama Inlet. During this period, Katama Inlet migrated east about 1000 m, narrowed from 400 to 100 m wide, changed depth from 7 to 2 m, and lengthened from 200 to 1000 m. Tidal flows in Katama Inlet are forced by sea level gradients resulting from the 3-hr phase lag between tides in Vineyard Sound and the Atlantic Ocean. Analyses of the momentum balances suggest that waves drive flows into the mouths of the inlets during storms. The timing of the storms relative to ebb and flood, and wind effects, may affect the discharge and sediment transport through the inlet. Winds and waves also drive alongshore flows on the ebb shoals. Lateral flows at bends in New River Inlet, which may be important to the along-inlet transfer of momentum and to mixing, are affected by winds. The importance of connections to additional inlets in multi-inlet systems will be discussed. Funded by ONR, ASD(R&E), NSF, Sea Grant, and NDSEG.

  8. Open air mineral treatment operations and ambient air quality: assessment and source apportionment.

    PubMed

    Escudero, M; Alastuey, A; Moreno, T; Querol, X; Pérez, P

    2012-11-01

    We present a methodology for evaluating and quantifying the impact of inhalable mineral dust resuspension close to a potentially important industrial point source, in this case an open air plant producing sand, flux and kaolin in the Capuchinos district of Alcañiz (Teruel, NE Spain). PM(10) levels at Capuchinos were initially high (42 μg m(-3) as the annual average with 91 exceedances of the EU daily limit value during 2007) but subsequently decreased (26 μg m(-3) with 16 exceedances in 2010) due to a reduced demand for minerals from the ceramic industry and construction sector during the first stages of the economic crisis. Back trajectory and local wind pattern analyses revealed only limited contribution from exotic PM sources such as African dust intrusions whereas there was clearly a strong link with the mineral stockpiles of the local industry. This link was reinforced by chemical and mineral speciation and source apportionment analysis which showed a dominance of mineral matter (sum of CO(3)(2-), SiO(2), Al(2)O(3), Ca, Fe, K, Mg, P, and Ti: mostly aluminosilicates) which in 2007 contributed 76% of the PM(10) mass (44 μg m(-3) on average). The contribution from Secondary Inorganic Aerosols (SIA, sum of SO(4)(2-), NO(3)(-) and NH(4)(+)) reached 8.4 μg m(-3), accounting for 14% of the PM(10) mass, similar to the amount of calcareous road dust estimated to be present (8 μg m(-3); 13%). Organic matter and elemental carbon contributed 5.3 μg m(-3) (9%) whereas marine aerosol (Na + Cl) levels were minor with an average concentration of 0.4 μg m(-3) (1% of the PM(10) mass). Finally, chemical and mineralogical analysis of stockpile samples and comparison with filter samples confirmed the local industry to be the major source of ambient PM(10) in the area.

  9. Consideration of Fugitives in Open-Air Cattle Operations

    EPA Pesticide Factsheets

    This document may be of assistance in applying the Title V air operating permit regulations. This document is part of the Title V Policy and Guidance Database available at www2.epa.gov/title-v-operating-permits/title-v-operating-permit-policy-and-guidance-document-index. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  10. Consideration of Fugitives in Open-Air Cattle Operations

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  11. Indoor air pollution by different heating systems: coal burning, open fireplace and central heating.

    PubMed

    Moriske, H J; Drews, M; Ebert, G; Menk, G; Scheller, C; Schöndube, M; Konieczny, L

    1996-11-01

    Investigations of indoor air pollution by different heating systems in private homes are described. Sixteen homes, 7 with coal burning, 1 with open fireplace (wood burning) and 8 with central heating have been investigated. We measured the concentrations of carbon monoxide, carbon dioxide and sedimented dust in indoor air, of total suspended particulates, heavy metals and of polycyclic aromatic hydrocarbons in indoor and outdoor air. Measurements were taken during winter (heating period) and during summer (non-heating period). Generally, we found higher indoor air pollution in homes with coal burning and open fireplace than in homes with central heating. Especially, the concentrations of carbon monoxide, sedimented dust and of some heavy metals were higher. In one case, we found also high indoor air pollution in a home with central heating. This apartment is on the ground floor of a block of flats, and the central heating system in the basement showed a malfunctioning of the exhaust system.

  12. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses.

    PubMed

    Feyereisen, Gary W; Francesconi, Wendy; Smith, Douglas R; Papiernik, Sharon K; Krueger, Erik S; Wente, Christopher D

    2015-03-01

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentrations and loads when open surface inlets were replaced with blind (in gravel capped with 30 cm of soil) or gravel (in very coarse sand/fine gravel) inlets. In Indiana, a pair of closed depressions in adjacent fields was fitted with open inlet tile risers and blind inlets in 2005 and monitored for flow and water chemistry. Paired comparisons on a storm event basis during the growing season for years 2006 to 2013 showed that TSS loads were 40.4 and 14.4 kg ha event for tile risers and blind inlets, respectively. Total P (TP) and soluble reactive P (SRP) loads were 66 and 50% less for the blind inlets, respectively. In Minnesota, TSS and SRP concentrations were monitored for 3 yr before and after modification of 24 open inlets to gravel inlets in an unreplicated large-field on-farm study. Median TSS concentrations were 97 and 8.3 mg L and median SRP concentrations were 0.099 and 0.064 mg L for the open inlet and gravel inlet periods, respectively. Median TSS and SRP concentrations were elevated for snowmelt vs. non-snowmelt seasons for open and gravel inlets. Both replacement designs reduced suspended sediment and P concentrations and loads. The Indiana study suggests blind inlets will be effective beyond a 10-yr service life.

  13. Characteristics of nitrogen balance in open-air and greenhouse vegetable cropping systems of China.

    PubMed

    Ti, Chaopu; Luo, Yongxia; Yan, Xiaoyuan

    2015-12-01

    Nitrogen (N) loss from vegetable cropping systems has become a significant environmental issue in China. In this study, estimation of N balances in both open-air and greenhouse vegetable cropping systems in China was established. Results showed that the total N input in open-air and greenhouse vegetable cropping systems in 2010 was 5.44 and 2.60 Tg, respectively. Chemical fertilizer N input in the two cropping systems was 201 kg N ha(-1) per season (open-air) and 478 kg N ha(-1) per season (greenhouse). The N use efficiency (NUE) was 25.9 ± 13.3 and 19.7 ± 9.4% for open-air and greenhouse vegetable cropping systems, respectively, significantly lower than that of maize, wheat, and rice. Approximately 30.6% of total N input was accumulated in soils and 0.8% was lost by ammonia volatilization in greenhouse vegetable system, while N accumulation and ammonia volatilization accounted for 19.1 and 11.1%, respectively, of total N input in open-air vegetable systems.

  14. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  15. Using Open and Interoperable Ways to Publish and Access LANCE AIRS Near-Real Time Data

    NASA Astrophysics Data System (ADS)

    Zhao, P.; Lynnes, C.; Vollmer, B.; Savtchenko, A. K.; Yang, W.

    2011-12-01

    Atmospheric Infrared Sounder (AIRS) Near-Real Time (NRT) data from the Land Atmosphere Near real time Capability for EOS (LANCE) provide the information on the global and regional atmospheric state with very low latency. An open and interoperable platform is useful to facilitate access to and integration of LANCE AIRS NRT data. This paper discusses the use of open-source software components to build Web services for publishing and accessing AIRS NRT data in the context of Service Oriented Architecture (SOA). The AIRS NRT data have also been made available through an OPeNDAP server. OPeNDAP allows several open-source netCDF-based tools such as Integrated Data Viewer, Ferret and Panoply to directly display the Level 2 data over the network. To enable users to locate swath data files in the OPeNDAP server that lie within a certain geographical area, graphical "granule maps" are being added to show the outline of each file on a map of the Earth. The metadata of AIRS NRT data and services is then explored to implement information advertisement and discovery in catalogue systems. Datacasting, an RSS-based technology for accessing Earth Science data and information to facilitate the subscriptions to AIRS NRT data availability, filtering, downloading and viewing data, is also discussed. To provide an easy entry point to AIRS NRT data and services, a Web portal designed for customized data downloading and visualization is introduced.

  16. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control...

  17. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control...

  18. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control...

  19. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control...

  20. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control...

  1. Open-loop heat-recovery dryer

    SciTech Connect

    TeGrotenhuis, Ward Evan

    2013-11-05

    A drying apparatus is disclosed that includes a drum and an open-loop airflow pathway originating at an ambient air inlet, passing through the drum, and terminating at an exhaust outlet. A passive heat exchanger is included for passively transferring heat from air flowing from the drum toward the exhaust outlet to air flowing from the ambient air inlet toward the drum. A heat pump is also included for actively transferring heat from air flowing from the passive heat exchanger toward the exhaust outlet to air flowing from the passive heat exchanger toward the drum. A heating element is also included for further heating air flowing from the heat pump toward the drum.

  2. Attic Inlet Technology Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Attic inlets are a popular addition for new construction and energy saving retrofits. Proper management of attic inlets is necessary to get maximum benefits from the system and reduce the likelihood of moisture-related problems in the structure. Solar energy levels were determined for the continen...

  3. Stepped inlet optical panel

    DOEpatents

    Veligdan, James T.

    2001-01-01

    An optical panel includes stacked optical waveguides having stepped inlet facets collectively defining an inlet face for receiving image light, and having beveled outlet faces collectively defining a display screen for displaying the image light channeled through the waveguides by internal reflection.

  4. Supersonic Elliptical Ramp Inlet

    NASA Technical Reports Server (NTRS)

    Adamson, Eric E. (Inventor); Fink, Lawrence E. (Inventor); Fugal, Spencer R. (Inventor)

    2016-01-01

    A supersonic inlet includes a supersonic section including a cowl which is at least partially elliptical, a ramp disposed within the cowl, and a flow inlet disposed between the cowl and the ramp. The ramp may also be at least partially elliptical.

  5. Regulation of Stomatal Defense by Air Relative Humidity1[OPEN

    PubMed Central

    Chitrakar, Reejana; Thompson, Blaine K.; Obulareddy, Nisita; Hambright, W. Sealy

    2016-01-01

    It has long been observed that environmental conditions play crucial roles in modulating immunity and disease in plants and animals. For instance, many bacterial plant disease outbreaks occur after periods of high humidity and rain. A critical step in bacterial infection is entry into the plant interior through wounds and natural openings, such as stomata, which are adjustable microscopic pores in the epidermal tissue. Several studies have shown that stomatal closure is an integral part of the plant immune response to reduce pathogen invasion. In this study, we found that high humidity can effectively compromise Pseudomonas syringae-triggered stomatal closure in both Phaseolus vulgaris and Arabidopsis (Arabidopsis thaliana), which is accompanied by early up-regulation of the jasmonic acid (JA) pathway and simultaneous down-regulation of salicylic acid (SA) pathway in guard cells. Furthermore, SA-dependent response, but not JA-dependent response, is faster in guard cells than in whole leaves, suggesting that the SA signaling in guard cells may be independent from other cell types. Thus, we conclude that high humidity, a well-known disease-promoting environmental condition, acts in part by suppressing stomatal defense and is linked to hormone signaling in guard cells. PMID:27702841

  6. Traffic-related air quality assessment for open road tolling highway facility.

    PubMed

    Lin, Jie; Yu, Dan

    2008-09-01

    Open road tolling (ORT) design has been considered as an effective means of smoothing highway traffic and reducing travel delay on toll highways. In this paper it is demonstrated that ORT can also achieve significant air quality benefits over the conventional toll plaza design. The near roadside carbon monoxide (CO) concentration levels can be reduced by up to 37%, and diesel particulate matter (DPM) emissions can decrease by as much as 58%. These large expected air quality benefits have great implications to the regional efforts of reducing mobile source air pollution toward achieving attainment status and healthier living environment.

  7. Study of hydraulic air compression for Ocean Thermal Energy Conversion open-cycle application

    NASA Astrophysics Data System (ADS)

    Golshani, A.; Chen, F. C.

    1983-01-01

    A hydraulic air compressor, which requires no mechanical moving parts and operates in a nearly isothermal mode, can be an alternative for the noncondensible gas disposal of an Ocean Thermal Energy Conversion (OTEC) open-cycle power system. The compressor requires only a downward flow of water to accomplish air compression. An air compressor test loop was assembled and operated to obtain test data that would lead to the design of an OTEC hydraulic air compressor. A one dimensional, hydraulic gas compressor, computer model was employed to simulate the laboratory experiments, and it was tuned to fit the test results. A sensitivity study that shows the effects of various parameters on the applied head of the hydraulic air compression is presented.

  8. Identifying and Reducing Health Risks Associated with Open-Air Burn Pits

    DTIC Science & Technology

    2013-04-01

    open-air burn pits. 15. SUBJECT TERMS Burn Pit Registry, incinerator, gasification, recycling , composting, particulate matter. 16...Registry, incinerator, gasification, recycling , composting, particulate matter. Classification: Unclassified DOD... bottles of water. Each pallet was shrink wrapped in plastic. I was also shown the location of our dining facility, where we ate off plastic plates with

  9. Flight test results of an automatic support system on board a YF-12A airplane. [for jet engine inlet air control

    NASA Technical Reports Server (NTRS)

    Love, J. E.

    1974-01-01

    An automatic support system concept that isolated faults in an existing nonavionics subsystem was flight tested up to a Mach number of 3. The adaptation of the automated support concept to an existing system (the jet engine automatic inlet control system) caused most of the problems one would expect to encounter in other applications. These problems and their solutions are discussed. Criteria for integrating automatic support into the initial design of new subsystems are included in the paper. Cost effectiveness resulted from both the low maintenance of the automated system and the man-hour saving resulting from the real time diagnosis of the monitored subsystem.

  10. Improving commercial broiler attic inlet ventilation thorugh CFD analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of solar heated attic air is an area of increasing interest in commercial poultry production. Attic inlets satisfy the demand for alternative heating while being simple to implement in an existing poultry house. A number of demonstration projects have suggested that attic inlets may decrease...

  11. Inlet Geomorphology Evolution Work Unit

    DTIC Science & Technology

    2015-10-30

    Coastal Inlets Research Program Inlet Geomorphology Evolution Work Unit The Inlet Geomorphology Evolution work unit of the CIRP develops methods...morphologic response. Presently, the primary tool of the Inlet Geomorphology Evolution work unit is the Sediment Mobility Tool (SMT), which allows the user

  12. OpenAQ: A Platform to Aggregate and Freely Share Global Air Quality Data

    NASA Astrophysics Data System (ADS)

    Hasenkopf, C. A.; Flasher, J. C.; Veerman, O.; DeWitt, H. L.

    2015-12-01

    Thousands of ground-based air quality monitors around the world publicly publish real-time air quality data; however, researchers and the public do not have access to this information in the ways most useful to them. Often, air quality data are posted on obscure websites showing only current values, are programmatically inaccessible, and/or are in inconsistent data formats across sites. Yet, historical and programmatic access to such a global dataset would be transformative to several scientific fields, from epidemiology to low-cost sensor technologies to estimates of ground-level aerosol by satellite retrievals. To increase accessibility and standardize this disparate dataset, we have built OpenAQ, an innovative, open platform created by a group of scientists and open data programmers. The source code for the platform is viewable at github.com/openaq. Currently, we are aggregating, storing, and making publicly available real-time air quality data (PM2.5, PM10, SO2, NO2, and O3) via an Application Program Interface (API). We will present the OpenAQ platform, which currently has the following specific capabilities: A continuous ingest mechanism for some of the most polluted cities, generalizable to more sources An API providing data-querying, including ability to filter by location, measurement type and value and date, as well as custom sort options A generalized, chart-based visualization tool to explore data accessible via the API At this stage, we are seeking wider participation and input from multiple research communities in expanding our data retrieval sites, standardizing our protocols, receiving feedback on quality issues, and creating tools that can be built on top of this open platform.

  13. Effects on inlet technology on cruise speed selection

    NASA Technical Reports Server (NTRS)

    Bangert, L. H.; Santman, D. M.; Horie, G.; Miller, L. D.

    1980-01-01

    The impact of cruise speed on technology level for certain aircraft components is examined. External-compression inlets were compared with mixed compression, self starting inlets at cruise Mach numbers of 2.0 and 2.3. Inlet engine combinations that provided the greatest aircraft range were identified. Results show that increased transonic to cruise corrected air flow ratio gives decreased range for missions dominated by supersonic cruise. It is also found important that inlets be designed to minimize spillage drag at subsonic cruise, because of the need for efficient performance for overland operations. The external compression inlet emerged as the probable first choice at Mach 2.0, while the self starting inlet was the probable first choice at Mach 2.3. Airframe propulsion system interference effects were significant, and further study is needed to assess the existing design methods and to develop improvements.

  14. CFD numerical simulation of Archimedes spiral inlet hydrocyclone

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wei, L.; Chang, B. H.; Xing, J. L.; Jia, K.

    2013-12-01

    For traditional linear type inlet, hydrocyclone has an unstable inner field, high turbulence intensity and low separation efficiency, this paper proposes an inlet mode that uses an Archimedes spiral hydrocyclone. A Mixture liquid-solid multiphase flow model combined with the kinetic theory of granular flow was used to simulate the high concentration water-sand-air three-phase flow in a hydrocyclone. We analyzed the pressure field, velocity field and turbulent kinetic energy and compared with traditional linear type inlet hydrocyclone inner field. The results show that Archimedes spiral inlet hydrocyclone's pressure field is evenly distributed. The Archimedes spiral inlet hydrocyclone can guide and accelerate the mixture flow and produce small forced vortex and less short circuit flow. The particles easily go to the outer vortex and are separated. The Archimedes spiral inlet hydrocyclone has effectively improved the stability of inner flow field and separation efficiency.

  15. Inlet starting predictions for sidewall-compression scramjet inlets

    NASA Technical Reports Server (NTRS)

    Trexler, Carl A.

    1988-01-01

    While inlet capture, total pressure recovery, and compression are important performance parameters in the design of scramjet inlets, the inlet must be capable of starting. An analytical, inviscid method has been developed that provides first order starting information for sidewall-compression scramjet inlets and trends have been established for some of the parameters that affect inlet starting. These parameters include sidewall contraction ratio, cowl position, Mach number, sweep angle, fuel injection struts, and sidewall and strut compression angles. Results from the parametric study are compared with data from both no-strut and two-strut inlet models.

  16. Inlet Performance Characteristics from Wind-Tunnel Tests of a 0.10-Scale Air-Induction System Model of the YF-108A Airplane at Mach Numbers of 2.50, 2.76, and 3.00

    NASA Technical Reports Server (NTRS)

    Blackaby, James R.; Lyman, E. Gene; Altermann, John A., III

    1959-01-01

    Inlet-performance and external-drag-coefficient characteristics are presented without analysis. Effects are shown of variations of fuselage boundary-layer diverter profile, bleed-surface porosity, bleed-exit area, and inlet ramp, and lip angle.

  17. The survival of foot-and-mouth disease virus in open air conditions.

    PubMed Central

    Donaldson, A. I.; Ferris, N. P.

    1975-01-01

    The influence of the Open Air Factor (OAF) and daylight on the survival of foot-and-mouth disease (FMD) virus held as captured aerosols on spider microthreads has been investigated. Virus inactivation due to OAF was slight. Similarly, the effect of daylight on the survival of virus was not marked. The results are discussed in relation to the airborne spread of FMD virus in nature. PMID:168250

  18. Increasing the object recognition distance of compact open air on board vision system

    NASA Astrophysics Data System (ADS)

    Kirillov, Sergey; Kostkin, Ivan; Strotov, Valery; Dmitriev, Vladimir; Berdnikov, Vadim; Akopov, Eduard; Elyutin, Aleksey

    2016-10-01

    The aim of this work was developing an algorithm eliminating the atmospheric distortion and improves image quality. The proposed algorithm is entirely software without using additional hardware photographic equipment. . This algorithm does not required preliminary calibration. It can work equally effectively with the images obtained at a distances from 1 to 500 meters. An algorithm for the open air images improve designed for Raspberry Pi model B on-board vision systems is proposed. The results of experimental examination are given.

  19. Dimensional approach on hot air turbine power plant in opened cycle for straw recycling

    NASA Astrophysics Data System (ADS)

    Bălănescu, D. T.; Homutescu, V. M.; Atanasiu, M. V.

    2016-08-01

    Currently, disposal of straw is one of the biggest problems that crop plant producers are facing. The ideal case implies not only to get rid of straw but also to recover its energetic potential. In this context, the performance of a hot air turbine power plant operating in open cycle, with straw as fuel, was analyzed in a previous study and proved to be a very interesting solution for straw disposal. As consequence, dimensional analysis of the hot air turbine power plant is required into the next step and this makes the subject of the present study. The dimensional analysis is focused on the compressed air heater - the largest component of the Power Plant, with crucial role in what concerns its entire size and mass. Once both performance and dimensional analysis performed, the final conclusions are drawn in an overall approach, by taking also into consideration the economic aspects.

  20. Next Generation Air Quality Platform: Openness and Interoperability for the Internet of Things.

    PubMed

    Kotsev, Alexander; Schade, Sven; Craglia, Massimo; Gerboles, Michel; Spinelle, Laurent; Signorini, Marco

    2016-03-18

    The widespread diffusion of sensors, mobile devices, social media and open data are reconfiguring the way data underpinning policy and science are being produced and consumed. This in turn is creating both opportunities and challenges for policy-making and science. There can be major benefits from the deployment of the IoT in smart cities and environmental monitoring, but to realize such benefits, and reduce potential risks, there is an urgent need to address current limitations, including the interoperability of sensors, data quality, security of access and new methods for spatio-temporal analysis. Within this context, the manuscript provides an overview of the AirSensEUR project, which establishes an affordable open software/hardware multi-sensor platform, which is nonetheless able to monitor air pollution at low concentration levels. AirSensEUR is described from the perspective of interoperable data management with emphasis on possible use case scenarios, where reliable and timely air quality data would be essential.

  1. Next Generation Air Quality Platform: Openness and Interoperability for the Internet of Things

    PubMed Central

    Kotsev, Alexander; Schade, Sven; Craglia, Massimo; Gerboles, Michel; Spinelle, Laurent; Signorini, Marco

    2016-01-01

    The widespread diffusion of sensors, mobile devices, social media and open data are reconfiguring the way data underpinning policy and science are being produced and consumed. This in turn is creating both opportunities and challenges for policy-making and science. There can be major benefits from the deployment of the IoT in smart cities and environmental monitoring, but to realize such benefits, and reduce potential risks, there is an urgent need to address current limitations, including the interoperability of sensors, data quality, security of access and new methods for spatio-temporal analysis. Within this context, the manuscript provides an overview of the AirSensEUR project, which establishes an affordable open software/hardware multi-sensor platform, which is nonetheless able to monitor air pollution at low concentration levels. AirSensEUR is described from the perspective of interoperable data management with emphasis on possible use case scenarios, where reliable and timely air quality data would be essential. PMID:26999160

  2. Coastal Inlets Research Program

    DTIC Science & Technology

    2014-04-01

    Tech Report: Fate of fines through the dredging process Inlet Geomorphology FY14 Plans  CHETN: Nearshore Berm Working Meeting Summary of Future... Geomorphology FY13 Accomplishments Release 3D Sediment Resource Tool Nearshore Berm Publications Ft Myers Nearshore• Integrated to GMS • Designed to provide 3D

  3. Jet Inlet Efficiency

    DTIC Science & Technology

    2013-08-08

    AFRL-RW-EG-TR-2014-044 Jet Inlet Efficiency Nigel Plumb Taylor Sykes -Green Keith Williams John Wohleber Munitions Aerodynamics Sciences...CONTRACT NUMBER N/A 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) Nigel Plumb Taylor Sykes -Green Keith Williams John

  4. Storage corrosion of materials and equipment: Temperature-humidity and aerochemical regimes indoors and in the open air

    SciTech Connect

    Strekalov, P.V.

    1994-07-01

    The following storage factors are considered: (1) the temperature-humidity complex (THC) in the open air at representative sites with cold, moderate, and subtropical humid climate; (2) the temperature and humidity differences between the open air and an atmospheric of semiclosed spaces; (3) the THC inside storage-spaces in a humid tropical climate; (4) the concentration of SO{sub 2} and Cl{sup -} in the open air and in different storage-spaces; (5) the categories of corrosivity of the atmosphere and methods for its evaluation indoors and outdoors.

  5. Effect of surface inlet type on suspended sediment transported through a subsurface drain tile system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Throughout the Prairie Pothole Region, subsurface tile and surface inlets are used to remove water from low-lying or poorly-drained soils. Open inlets are being increasingly converted to buried inlets in which perforated tile is placed in a trench of rock (i.e., a French drain) and buried below a la...

  6. Open hardware air quality station for monitoring ozone in port area

    NASA Astrophysics Data System (ADS)

    Massabo, Marco; Lima, Marco; Fedi, Adriano; Ferrari, Daniele; Pintus, Fabio; Bruzzone, Gabriele

    2015-04-01

    Improve the quality of the air is one of the most important challenges we are facing especially in urban area. The open hardware paradigm can promote the positive connection of institution and scientific community with citizen. The goal of this work is to describe how a well-known pollution sensing technology, such as the electrochemical one, may be adopted in an open hardware paradigm in order to realize a ground level ozone sensor station. Our approach is to use this type of sensors to complement and empower traditional measuring networks in order to provide a better support to the models and to the identification of the pollution sources. The calibration methodology is based on the online coupling of new sensor measurements and observations of official network. Several linear calibration and a linear error correction algorithm based on temperature are performed and evaluated. The new air quality station allows to increase the frequency of sampling up to minutes and, due to the low cost, can stimulate the utilization by no-professionals. We test the air quality station in portal area and compare the results with traditional observations.

  7. Using Open and Interoperable Ways to Publish and Access LANCE AIRS Near-Real Time Data

    NASA Technical Reports Server (NTRS)

    Zhao, Peisheng; Lynnes, Christopher; Vollmer, Bruce; Savtchenko, Andrey; Theobald, Michael; Yang, Wenli

    2011-01-01

    The Atmospheric Infrared Sounder (AIRS) Near-Real Time (NRT) data from the Land Atmosphere Near real-time Capability for EOS (LANCE) element at the Goddard Earth Sciences Data and Information Services Center (GES DISC) provides information on the global and regional atmospheric state, with very low temporal latency, to support climate research and improve weather forecasting. An open and interoperable platform is useful to facilitate access to, and integration of, LANCE AIRS NRT data. As Web services technology has matured in recent years, a new scalable Service-Oriented Architecture (SOA) is emerging as the basic platform for distributed computing and large networks of interoperable applications. Following the provide-register-discover-consume SOA paradigm, this presentation discusses how to use open-source geospatial software components to build Web services for publishing and accessing AIRS NRT data, explore the metadata relevant to registering and discovering data and services in the catalogue systems, and implement a Web portal to facilitate users' consumption of the data and services.

  8. Quantitative comparison of a flared and a standard heated metal capillary inlet with a voltage-assisted air amplifier on an electrospray ionization linear ion trap mass spectrometer.

    PubMed

    Dixon, R Brent; Muddiman, David C

    2007-01-01

    The performance characteristics (i.e., ion abundance and electrospray ion current) of a flared and blunt-ended heated metal capillary were evaluated with a voltage-assisted air amplifier on a linear ion trap mass spectrometer (LTQ-MS). The results demonstrated that a standard capillary afforded higher ion abundance than a flared capillary, thus further work is necessary to investigate conditions for which significant benefits with the flared capillary will be observed. The compatibility of a voltage-assisted air amplifier is explored for both types of capillaries and in all cases resulted in improved ion abundance and spray current.

  9. An Autosampler and Field Sample Carrier for Maximizing Throughput Using an Open-Air, Surface Sampling Ion Source for MS

    EPA Science Inventory

    A recently developed, commercially available, open-air, surface sampling ion source for mass spectrometers provides individual analyses in several seconds. To realize its full throughput potential, an autosampler and field sample carrier were designed and built. The autosampler ...

  10. Cold start fuel/air mixture supply device for spark ignition internal combustion engines

    SciTech Connect

    Ross, G.E.D.

    1984-06-05

    A combined accelerator pump and cold start fuel/air mixture supply device has an automatic throttle valve in a mixture supply passage, a fuel control valve controlling flow of fuel drawn into the passage through an inlet upstream of the throttle valve, and an air valve upstream of the fuel inlet. A primary spring tends to seat the air valve. A light, secondary spring urges a plunger against the air valve to augment the load of the primary spring for a predetermined time interval after the engine begins to run under its own power. A valve in a pipe opens automatically at the end of the predetermined time interval to apply engine inlet manifold depression to the end of the plunger remote from the air valve and thereby to separate the plunger from the air valve so that only the primary spring acts on the air valve.

  11. Low-speed aerodynamic test of an axisymmetric supersonic inlet with variable cowl slot

    NASA Technical Reports Server (NTRS)

    Powell, A. G.; Welge, H. R.; Trefny, C. J.

    1985-01-01

    The experimental low-speed aerodynamic characteristics of an axisymmetric mixed-compression supersonic inlet with variable cowl slot are described. The model consisted of the NASA P-inlet centerbody and redesigned cowl with variable cowl slot powered by the JT8D single-stage fan simulator and driven by an air turbine. The model was tested in the NASA Lewis Research Center 9- by 15-foot low-speed tunnel at Mach numbers of 0, 0.1, and 0.2 over a range of flows, cowl slot openings, centerbody positions, and angles of attack. The variable cowl slot was effective in minimizing lip separation at high velocity ratios, showed good steady-state and dynamic distortion characteristics, and had good angle-of-attack tolerance.

  12. An open-access modeled passenger flow matrix for the global air network in 2010.

    PubMed

    Huang, Zhuojie; Wu, Xiao; Garcia, Andres J; Fik, Timothy J; Tatem, Andrew J

    2013-01-01

    The expanding global air network provides rapid and wide-reaching connections accelerating both domestic and international travel. To understand human movement patterns on the network and their socioeconomic, environmental and epidemiological implications, information on passenger flow is required. However, comprehensive data on global passenger flow remain difficult and expensive to obtain, prompting researchers to rely on scheduled flight seat capacity data or simple models of flow. This study describes the construction of an open-access modeled passenger flow matrix for all airports with a host city-population of more than 100,000 and within two transfers of air travel from various publicly available air travel datasets. Data on network characteristics, city population, and local area GDP amongst others are utilized as covariates in a spatial interaction framework to predict the air transportation flows between airports. Training datasets based on information from various transportation organizations in the United States, Canada and the European Union were assembled. A log-linear model controlling the random effects on origin, destination and the airport hierarchy was then built to predict passenger flows on the network, and compared to the results produced using previously published models. Validation analyses showed that the model presented here produced improved predictive power and accuracy compared to previously published models, yielding the highest successful prediction rate at the global scale. Based on this model, passenger flows between 1,491 airports on 644,406 unique routes were estimated in the prediction dataset. The airport node characteristics and estimated passenger flows are freely available as part of the Vector-Borne Disease Airline Importation Risk (VBD-Air) project at: www.vbd-air.com/data.

  13. An Open-Access Modeled Passenger Flow Matrix for the Global Air Network in 2010

    PubMed Central

    Huang, Zhuojie; Wu, Xiao; Garcia, Andres J.; Fik, Timothy J.; Tatem, Andrew J.

    2013-01-01

    The expanding global air network provides rapid and wide-reaching connections accelerating both domestic and international travel. To understand human movement patterns on the network and their socioeconomic, environmental and epidemiological implications, information on passenger flow is required. However, comprehensive data on global passenger flow remain difficult and expensive to obtain, prompting researchers to rely on scheduled flight seat capacity data or simple models of flow. This study describes the construction of an open-access modeled passenger flow matrix for all airports with a host city-population of more than 100,000 and within two transfers of air travel from various publicly available air travel datasets. Data on network characteristics, city population, and local area GDP amongst others are utilized as covariates in a spatial interaction framework to predict the air transportation flows between airports. Training datasets based on information from various transportation organizations in the United States, Canada and the European Union were assembled. A log-linear model controlling the random effects on origin, destination and the airport hierarchy was then built to predict passenger flows on the network, and compared to the results produced using previously published models. Validation analyses showed that the model presented here produced improved predictive power and accuracy compared to previously published models, yielding the highest successful prediction rate at the global scale. Based on this model, passenger flows between 1,491 airports on 644,406 unique routes were estimated in the prediction dataset. The airport node characteristics and estimated passenger flows are freely available as part of the Vector-Borne Disease Airline Importation Risk (VBD-Air) project at: www.vbd-air.com/data. PMID:23691194

  14. Meteorological conditions are associated with physical activities performed in open-air settings

    NASA Astrophysics Data System (ADS)

    Suminski, Richard R.; Poston, Walker C.; Market, Patrick; Hyder, Melissa; Sara, Pyle A.

    2008-01-01

    Meteorological conditions (MC) are believed to modify physical activity. However, studies in this area are limited and none have looked at the associations between MC and physical activity in open-air settings. Therefore, we examined the relationships between MC and physical activities performed on sidewalks/streets and outdoor oval tracks. Observation techniques were used to count individuals walking to school, exercising on oval tracks and walking/jogging/biking on sidewalks/streets. Meteorological conditions were obtained from an Automated Surface Observing System located at a nearby airport for the same time periods physical activities were observed. On weekdays, fewer children were seen walking to school and more bicyclists were observed on sidewalks/streets as wind speed increased ( p < 0.05). Ambient and apparent temperatures were positively ( p < 0.05) and humidity and barometric pressure negatively ( p < 0.005) related to the number of individuals walking on the track. Meteorological conditions were not significantly associated with physical activities observed on weekends. Multiple linear regression analyses showed that apparent temperature (+), barometric pressure (-) and dew point (-) accounted for 58.0% of the variance in the number of walkers on the track. A significant proportion of the variance (>30%) in the number of joggers and the length of time they jogged was accounted for by apparent temperature (+) and dew point (-). We found that meteorological conditions are related to physical activity in open-air settings. The results embellish the context in which environmental-physical activity relationships should be interpreted and provide important information for researchers applying the observation method in open-air settings.

  15. Numerical evaluation of an innovative cup layout for open volumetric solar air receivers

    NASA Astrophysics Data System (ADS)

    Cagnoli, Mattia; Savoldi, Laura; Zanino, Roberto; Zaversky, Fritz

    2016-05-01

    This paper proposes an innovative volumetric solar absorber design to be used in high-temperature air receivers of solar power tower plants. The innovative absorber, a so-called CPC-stacked-plate configuration, applies the well-known principle of a compound parabolic concentrator (CPC) for the first time in a volumetric solar receiver, heating air to high temperatures. The proposed absorber configuration is analyzed numerically, applying first the open-source ray-tracing software Tonatiuh in order to obtain the solar flux distribution on the absorber's surfaces. Next, a Computational Fluid Dynamic (CFD) analysis of a representative single channel of the innovative receiver is performed, using the commercial CFD software ANSYS Fluent. The solution of the conjugate heat transfer problem shows that the behavior of the new absorber concept is promising, however further optimization of the geometry will be necessary in order to exceed the performance of the classical absorber designs.

  16. Innovative open air brayton combined cycle systems for the next generation nuclear power plants

    NASA Astrophysics Data System (ADS)

    Zohuri, Bahman

    The purpose of this research was to model and analyze a nuclear heated multi-turbine power conversion system operating with atmospheric air as the working fluid. The air is heated by a molten salt, or liquid metal, to gas heat exchanger reaching a peak temperature of 660 0C. The effects of adding a recuperator or a bottoming steam cycle have been addressed. The calculated results are intended to identify paths for future work on the next generation nuclear power plant (GEN-IV). This document describes the proposed system in sufficient detail to communicate a good understanding of the overall system, its components, and intended uses. The architecture is described at the conceptual level, and does not replace a detailed design document. The main part of the study focused on a Brayton --- Rankine Combined Cycle system and a Recuperated Brayton Cycle since they offer the highest overall efficiencies. Open Air Brayton power cycles also require low cooling water flows relative to other power cycles. Although the Recuperated Brayton Cycle achieves an overall efficiency slightly less that the Brayton --- Rankine Combined Cycle, it is completely free of a circulating water system and can be used in a desert climate. Detailed results of modeling a combined cycle Brayton-Rankine power conversion system are presented. The Rankine bottoming cycle appears to offer a slight efficiency advantage over the recuperated Brayton cycle. Both offer very significant advantages over current generation Light Water Reactor steam cycles. The combined cycle was optimized as a unit and lower pressure Rankine systems seem to be more efficient. The combined cycle requires a lot less circulating water than current power plants. The open-air Brayton systems appear to be worth investigating, if the higher temperatures predicted for the Next Generation Nuclear Plant do materialize.

  17. Margaret and Rachel McMillan: Their Influences on Open-Air Nursery Education and Early Years Teacher Education

    ERIC Educational Resources Information Center

    Liebovich, Betty

    2014-01-01

    Rachel and Margaret McMillan created an open-air nursery in Deptford, London that has influenced early years education for 100 years. Their vision for young children living in poverty and deprivation to have access to fresh air through outdoor learning, nutritious meals, and an enriching environment to explore and develop has been embraced and…

  18. Exposure of workers to airborne microorganisms in open-air swine houses.

    PubMed

    Chang, C W; Chung, H; Huang, C F; Su, H J

    2001-01-01

    This study quantified the levels of airborne microorganisms in six swine farms with more than 10,000 pigs in subtropical Taiwan. We evaluated breeding, growing, and finishing stalls, which were primarily open-air buildings, as well as partially enclosed farrowing and nursery piggeries. Airborne culturable bacteria, gram-negative bacteria, and fungi were placed on appropriate media by using an all-glass impinger or single-stage Andersen microbial sampler. Results showed that mean concentrations of culturable bacteria and gram-negative bacteria were 3.3 x 10(5) and 143.7 CFU/m(3), respectively. The concentration of airborne culturable fungi was about 10(3) CFU/m(3), with Cladosporium the predominant genus. The highest airborne levels of culturable bacteria and gram-negative bacteria were identified in the finishing units. The air of the nursery stalls was the least contaminated with culturable and gram-negative bacteria. Irregular and infrequent cleaning, high pig density, no separation of wastes from pen floors, and accumulation of water as a result of the processes for cleaning and reducing pig temperature possibly compromise the benefits of the open characteristic of the finishing units with respect to airborne bacterial concentration.

  19. Permitting Considerations for Installation of Inlet Air Foggers on Simple Cycle Combustion Turbines at the Duke Power Lincoln Combustion Turbine Facility

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  20. A framework for air quality monitoring based on free public data and open source tools

    NASA Astrophysics Data System (ADS)

    Nikolov, Hristo; Borisova, Denitsa

    2014-10-01

    In the recent years more and more widely accepted by the Space agencies (e.g. NASA, ESA) is the policy toward provision of Earth observation (EO) data and end products concerning air quality especially in large urban areas without cost to researchers and SMEs. Those EO data are complemented by increasing amount of in-situ data also provided at no cost either from national authorities or having crowdsourced origin. This accessibility together with the increased processing capabilities of the free and open source software is a prerequisite for creation of solid framework for air modeling in support of decision making at medium and large scale. Essential part of this framework is web-based GIS mapping tool responsible for dissemination of the output generated. In this research an attempt is made to establish a running framework based solely on openly accessible data on air quality and on set of freely available software tools for processing and modeling taking into account the present status quo in Bulgaria. Among the primary sources of data, especially for bigger urban areas, for different types of gases and dust particles, noted should be the National Institute of Meteorology and Hydrology of Bulgaria (NIMH) and National System for Environmental Monitoring managed by Bulgarian Executive Environmental Agency (ExEA). Both authorities provide data for concentration of several gases just to mention CO, CO2, NO2, SO2, and fine suspended dust (PM10, PM2.5) on monthly (for some data on daily) basis. In the framework proposed these data will complement the data from satellite-based sensors such as OMI instrument aboard EOS-Aura satellite and from TROPOMI instrument payload for future ESA Sentinel-5P mission. Integral part of the framework is the modern map for the land use/land cover which is provided from EEA by initiative GIO Land CORINE. This map is also a product from EO data distributed at European level. First and above all, our effort is focused on provision to the

  1. Noise radiation directivity from a wind-tunnel inlet with inlet vanes and duct wall linings

    NASA Technical Reports Server (NTRS)

    Soderman, P. T.; Phillips, J. D.

    1986-01-01

    The acoustic radiation patterns from a 1/15th scale model of the Ames 80- by 120-Ft Wind Tunnel test section and inlet have been measured with a noise source installed in the test section. Data were acquired without airflow in the duct. Sound-absorbent inlet vanes oriented parallel to each other, or splayed with a variable incidence relative to the duct long axis, were evaluated along with duct wall linings. Results show that splayed vans tend to spread the sound to greater angles than those measured with the open inlet. Parallel vanes narrowed the high-frequency radiation pattern. Duct wall linings had a strong effect on acoustic directivity by attenuating wall reflections. Vane insertion loss was measured. Directivity results are compared with existing data from square ducts. Two prediction methods for duct radiation directivity are described: one is an empirical method based on the test data, and the other is a analytical method based on ray acoustics.

  2. Air quality impact assessment of multiple open pit coal mines in northern Colombia.

    PubMed

    Huertas, José I; Huertas, María E; Izquierdo, Sebastián; González, Enrique D

    2012-01-01

    The coal mining region in northern Colombia is one of the largest open pit mining regions of the world. In 2009, there were 8 mining companies in operation with an approximate coal production of ∼70 Mtons/year. Since 2007, the Colombian air quality monitoring network has reported readings that exceed the daily and annual air quality standards for total suspended particulate (TSP) matter and particles with an equivalent aerodynamic diameter smaller than 10 μm (PM₁₀) in nearby villages. This paper describes work carried out in order to establish an appropriate clean air program for this region, based on the Colombian national environmental authority requirement for modeling of TSP and PM(10) dispersion. A TSP and PM₁₀ emission inventory was initially developed, and topographic and meteorological information for the region was collected and analyzed. Using this information, the dispersion of TSP was modeled in ISC3 and AERMOD using meteorological data collected by 3 local stations during 2008 and 2009. The results obtained were compared to actual values measured by the air quality monitoring network. High correlation coefficients (>0.73) were obtained, indicating that the models accurately described the main factors affecting particle dispersion in the region. The model was then used to forecast concentrations of particulate matter for 2010. Based on results from the model, areas within the modeling region were identified as highly, fairly, moderately and marginally polluted according to local regulations. Additionally, the contribution particulate matter to the pollution at each village was estimated. Using these predicted values, the Colombian environmental authority imposed new decontamination measures on the mining companies operating in the region. These measures included the relocation of three villages financed by the mine companies based on forecasted pollution levels.

  3. Characterisation of the impact of open biomass burning on urban air quality in Brisbane, Australia.

    PubMed

    He, Congrong; Miljevic, Branka; Crilley, Leigh R; Surawski, Nicholas C; Bartsch, Jennifer; Salimi, Farhad; Uhde, Erik; Schnelle-Kreis, Jürgen; Orasche, Jürgen; Ristovski, Zoran; Ayoko, Godwin A; Zimmermann, Ralf; Morawska, Lidia

    2016-05-01

    Open biomass burning from wildfires and the prescribed burning of forests and farmland is a frequent occurrence in South-East Queensland (SEQ), Australia. This work reports on data collected from 10 to 30 September 2011, which covers the days before (10-14 September), during (15-20 September) and after (21-30 September) a period of biomass burning in SEQ. The aim of this project was to comprehensively quantify the impact of the biomass burning on air quality in Brisbane, the capital city of Queensland. A multi-parameter field measurement campaign was conducted and ambient air quality data from 13 monitoring stations across SEQ were analysed. During the burning period, the average concentrations of all measured pollutants increased (from 20% to 430%) compared to the non-burning period (both before and after burning), except for total xylenes. The average concentration of O3, NO2, SO2, benzene, formaldehyde, PM10, PM2.5 and visibility-reducing particles reached their highest levels for the year, which were up to 10 times higher than annual average levels, while PM10, PM2.5 and SO2 concentrations exceeded the WHO 24-hour guidelines and O3 concentration exceeded the WHO maximum 8-hour average threshold during the burning period. Overall spatial variations showed that all measured pollutants, with the exception of O3, were closer to spatial homogeneity during the burning compared to the non-burning period. In addition to the above, elevated concentrations of three biomass burning organic tracers (levoglucosan, mannosan and galactosan), together with the amount of non-refractory organic particles (PM1) and the average value of f60 (attributed to levoglucosan), reinforce that elevated pollutant concentration levels were due to emissions from open biomass burning events, 70% of which were prescribed burning events. This study, which is the first and most comprehensive of its kind in Australia, provides quantitative evidence of the significant impact of open biomass burning

  4. Ice Protection of Turbojet Engines by Inertia Separation of Water III : Annular Submerged Inlets

    NASA Technical Reports Server (NTRS)

    Von Glahn, Uwe

    1948-01-01

    Aerodynamic and icing studies were conducted on a one-half-scale model of an annular submerged inlet for use with axial-flow turbojet engines. Pressure recoveries, screen radial-velocity profiles, circumferential mass-flow variations, and icing characteristics were determined at the compressor inlet. In order to be effective in maintaining water-free induction air, the inlet gap must be extremely small and ram-pressure recoveries consequently are low, the highest achieved being 65 percent at inlet-velocity ratio of 0.86. All inlets exhibited considerable screen icing. Severe mass-flow shifts occurred at angles of attack.

  5. Effect of alternative surface inlet designs on sediment and phosphorus drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  6. Synthesis of Nano-Crystalline Materials in Open-Air Laboratory: A Case Study of Tobacco.

    PubMed

    Satpati, Biswarup; Bhattacherjee, Ashis; Roy, Madhusudan

    2015-02-01

    The work deals with synthesis of nano-crystalline materials in open-air laboratory and in-depth investigation of the tobacco sample of one branded cigarette and its ash using high-resolution transmission electron microscopy and associated techniques. It exhibits the presence of nanocrystals and nanorods of various oxides in cigarette ash. The structure, shape, size and composition of these nanocrystals and nanorods are explored. The energy dispersive X-ray spectra from different regions of the tobacco sample and its ash using high-angle annular dark field scanning/transmission electron microscopy mode are utilized to obtain elemental composition and their relative abundances. For a detailed distribution of different elements in the nanorods, elemental mapping using energy-filtered transmission electron microscopy is also presented. The results highlight the conversion of amorphous constituents of tobacco to nanomaterials on combustion at low temperatures, thus mixing up in the atmosphere.

  7. International Diffusion of Open Path FTIR Technology and Air Monitoring Methods: Taiwan (Republic of China).

    PubMed

    Giese-Bogdan, Stefan It; Levine, Steven P

    1996-08-01

    International cooperation and diffusion of environmental technologies is a central goal of the U.S. EPA Environmental Technology Initiative, and is of great interest to many countries. One objective is to exchange knowledge and skills concerning new monitoring technologies. In this case, the technology was open path Fourier Transform Infrared Spectrometry (op-FTIR). Taiwan is a high-technology, newly industrialized country. Because of air pollution problems, it is interested in obtaining skills, knowledge, and instrumentation for monitoring air pollutants. In April 1994, the Industrial Technology Research Institute, Center for Industrial Safety and Health Technology (ITRI/CISH) in Hsinchu, Taiwan, requested intensive training in op-FTIR. Training was held between September 30,1994 and October 29,1994. During the stay, the instructor provided intensive training on op-FTIR theory as well as an introduction to available instrumentation and software. The training concluded with a field demonstration of the instrumentation in a manufacturing facility. This report gives an overview of the training methods, structure, and materials in the op-FTIR training course. It will also address various problems encountered while teaching this course. In addition, the potential use for this technology in industry as well as by the Taiwanese government will be explained.

  8. LOPES — Recent Results and Open Questions on the Radio Detection of Air Showers

    NASA Astrophysics Data System (ADS)

    Schröder, F. G.; Apel, W. D.; Arteaga-Velázquez, J. C.; Bähren, L.; Bekk, K.; Bertaina, M.; Biermann, P. L.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Falcke, H.; Fuchs, B.; Gemmeke, H.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Horneffer, A.; Huber, D.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Krömer, O.; Kuijpers, J.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Melissas, M.; Morello, C.; Oehlschläger, J.; Palmieri, N.; Pierog, T.; Rautenberg, J.; Rebel, H.; Roth, M.; Rühle, C.; Saftoiu, A.; Schieler, H.; Schmidt, A.; Schoo, S.; Sima, O.; Toma, G.; Trinchero, G. C.; Weindl, A.; Wochele, J.; Zabierowski, J.; Zensus, J. A.

    2015-08-01

    LOPES was a digital antenna array operating for approximately 10 years until spring 2013 at the Karlsruhe Institute of Technology (KIT). Triggered by the co-located KASCADE-Grande air-shower experiment, it measured the radio signal of around 1000 cosmic-ray air showers with energies E ≳ 1017 eV in an effective band of 43 - 74 MHz. Using the interferometric technique of cross-correlation beamforming, LOPES could reconstruct the shower direction with an accuracy < 0.7°, the shower energy with a precision < 20%, and the atmospheric depth of the shower maximum, Xmax, with a precision < 95g/cm2. In particular the reconstruction of the shower maximum suffers from significant measurement uncertainties due to the radio-loud environment of the site. This article summarizes our latest results on the reconstruction of the shower maximum, using two independent methods: the steepness of the hyperbolic radio wavefront and the slope of the lateral distribution of the radio amplitude. Moreover, we show vectorial measurements of the electric field with the tripole antennas of the latest LOPES setup. Finally, we discuss open questions as well as the potential impact of the lessons learned at LOPES for future antenna arrays.

  9. Diffuse discharge produced by repetitive nanosecond pulses in open air, nitrogen, and helium

    NASA Astrophysics Data System (ADS)

    Shao, Tao; Tarasenko, Victor F.; Zhang, Cheng; Baksht, Evgeni Kh.; Zhang, Dongdong; Erofeev, Mikhail V.; Ren, Chengyan; Shutko, Yuliya V.; Yan, Ping

    2013-03-01

    Atmospheric-pressure gas discharge driven by high voltage pulses with fast rise-time and short duration has attracted significant attention for various plasma applications. In this paper, discharges were generated in a highly non-uniform electric field by point-plane gaps in open air by four repetitive nanosecond-pulse generators with repetition rate up to 1 kHz. The rise time of generators was 25 (generator #1), 15 (generator #2), 3 (generator #3), and 0.2 ns (generator #4) and a full width at half maximum was 40, 30-40, 5, and 1 ns, respectively. The experimental results show that there were typical discharge fashions, i.e., corona, diffuse, spark, or arc modes. The variables affecting the discharge characteristics, including the gap spacing and applied pulse parameters, were investigated. Especially, the diffuse discharges were investigated and discussed. With generator #1 at voltage 70-120 kV, characteristics of measured x-rays on the discharge modes were studied, and it indicates that counts of x-rays in a diffuse discharge are up to a peak value under the experimental conditions. With amplitude of voltage pulses in incident wave up to 18 (generator #3) and 12.5 kV (generator #4), runaway electron beam in low pressure helium, nitrogen, and air in a pulse-periodic mode of discharge with repetition rate up to 1 kHz was obtained. Electron beam was registered behind a thin foil in a pressure range from several to tens of Torr. X-ray radiation was obtained in a wide range of pressures, as well as at atmospheric pressure of helium, nitrogen, and air. Voltage pulses of positive and negative polarities were used. Generation of runaway electrons with pulses of positive polarity appeared because of reflected voltage pulses of reverse polarity.

  10. Effect of ozone and open air factor against aerosolized Micrococcus luteus.

    PubMed

    Bailey, Roger; Fielding, Louise; Young, Andy; Griffith, Chris

    2007-12-01

    Because of increased concerns over failures in cleaning, the role of bioaerosols, and the environmental and clinical persistence of pathogens, the evaluation of novel decontaminants is increasingly important. The bactericidal properties of open air factor (OAF; a collection of highly reactive chemical species) were identified in the 1970s; however, the potential practical applications of artificially generated OAF have been considered only recently. In this study, the effects of OAF against Micrococcus luteus were investigated. OAF was generated and distributed in a bioaerosol test chamber by delivery of monoterpenes into ozonated air (0.1 ppm) at concentrations of 2.0 (high), 0.75 (medium), or 0.3 (low) mgm(-3) h(-1). M. luteus was aerosolized, and the number of culturable survivors was determined after 2, 5, 10, 20, and 60 min. Culturable bacteria were enumerated by aerobic plate counts in all-glass impinger fluid. Data were analyzed for statistical significance using one- or two-way analyses of variance. When aerosolized bacteria were exposed to ozone alone (0.05, 0.1, and 2 ppm), a significant (up to 3-log) reduction was observed at all concentrations, and the effect was time dependent. When exposed to the cyclic monoterpene alone, there were no significant differences between test samples and controls. When exposed to OAF (high and medium concentrations in 0.1 ppm ozone) there were significant differences after 20 min. These reductions were significantly greater than those achieved with ozone alone at 0.1 ppm. OAF is potentially an effective antibacterial agent that can reduce the microbial load in air. Because the technology uses reaction compounds naturally found in the environment, risks to health may be lower than those associated with ozone or other gaseous treatments. However, this hypothesis needs further investigation.

  11. Computational study of forced air-convection in open-cathode polymer electrolyte fuel cell stacks

    NASA Astrophysics Data System (ADS)

    Sasmito, A. P.; Lum, K. W.; Birgersson, E.; Mujumdar, A. S.

    A mathematical model for a polymer electrolyte fuel cell (PEFC) stack with an open-cathode manifold, where a fan provides the oxidant as well as cooling, is derived and studied. In short, the model considers two-phase flow and conservation of mass, momentum, species and energy in the ambient and PEFC stack, as well as conservation of charge and a phenomenological membrane and agglomerate model for the PEFC stack. The fan is resolved as an interfacial condition with a polynomial expression for the static pressure increase over the fan as a function of the fan velocity. The results suggest that there is strong correlation between fan power rating, the height of cathode flow-field and stack performance. Further, the placement of the fan - either in blowing or suction mode - does not give rise to a discernable difference in stack performance for the flow-field considered (metal mesh). Finally, it is noted that the model can be extended to incorporate other types of flow-fields and, most importantly, be employed for design and optimization of forced air-convection open-cathode PEFC stacks and adjacent fans.

  12. Effect of end-wall boundary layer and inlet turbulence on the flow field structures in the turbine stage

    NASA Astrophysics Data System (ADS)

    Jelinek, Tomas; Straka, Petr; Uruba, Vaclav

    2016-06-01

    The article deals with the effects of the inlet flow parameters on the flow field structures in axial turbine stage. The experiment was performed on the axial turbine stage rig with an air as a working medium. The variable inlet channel produced the different inlet turbulence intensity and different inlet end-wall boundary layer thickness, resp. different inlet velocity distribution was applied. The turbulence was measured by CTA probes. The measured parameters of the inlet velocity distribution and turbulence intensity across the inlet channel height are presented. Based on the experimental inlet parameters the CFD fully turbulent calculation of the flow field was made. The differences in outlet kinetic energy loss, outlet vane angle and the turbulence distribution in the vane mid-span section are depicted. Changes of secondary flow structures with the different inlet end-wall boundary layer thickness were observed on the vane outlet parameters.

  13. Newly Reported Lupus and Rheumatoid Arthritis in Relation to Deployment Within Proximity to a Documented Open-Air Burn Pit in Iraq

    DTIC Science & Technology

    2012-06-01

    Naval Health Research Center Newly Reported Lupus and Rheumatoid Arthritis in Relation to Deployment Within Proximity to a Documented Open-Air...Newly Reported Lupus and Rheumatoid Arthritis in Relation to Deployment Within Proximity to a Documented Open-Air Burn Pit in Iraq Kelly A. Jones, MPH...exposure to smoke from documented open-air burn pits and newly reported lupus and rheumatoid arthritis among Millennium Cohort participants who have

  14. 14 CFR 25.1091 - Air induction.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operating surfaces from being directed into the engine or auxiliary power unit air inlet ducts in hazardous quantities, and the air inlet ducts must be located or protected so as to minimize the ingestion of...

  15. An Experimental Investigation of NACA Submerged Inlets at High Subsonic Speeds I: Inlets Forward of the Wing Leading Edge

    NASA Technical Reports Server (NTRS)

    Hall, Charles F; Barclay, F Dorn

    1948-01-01

    This report covers the first part of an experimental investigation of NACA submerged inlets at four locations on the fuselage of a fighter airplane model for Mach numbers from 0.30 to 0.875. Data are presented showing the characteristics of the model without inlets and with inlets 16.7 percent of the root chord forward of the wing-root leading edge and equipped with small boundary-layer deflectors. The data show that variations in the mass of air entering the inlet had a large effect on the ram-recovery ratio. Representative values of ram-recovery ratio were 0.50 with zero flow, 0.90 with 0.6 mass-flow coefficient, and 0.95 with 1.00 mass-flow coefficient. Variations in Mach number and angle of attack, in general, caused less than a 0.03 variation in the ram-recovery ratio.

  16. CHARACTERIZATION OF AIR EMISSIONS AND RESIDUAL ASH FROM OPEN BURNING OF ELECTRONIC WASTES DURING SIMULATED RUDIMENTALRY RECYCLING OPERATIONS

    EPA Science Inventory

    Air emissions and residual ash measurements were made from open, uncontrolled combustion of electronic waste (e-waste) during simulations of practices associated with rudimentary e-waste recycling operations. Circuit boards and insulated wires were separately burned to simulate p...

  17. Responses of soybeans and wheat to elevated CO2 in free-air and open top chamber systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With increasing demand for agricultural products, more confidence is needed concerning impacts of rising atmospheric CO2 on crop yields. Despite debate about the merits of free-air CO2 enrichment (FACE) and open top chamber (OTC) systems, there has been only one reported experiment directly compari...

  18. Visualizing Discipline of the Body in a German Open-Air School (1923-1939): Retrospection and Introspection

    ERIC Educational Resources Information Center

    Thyssen, Geert

    2007-01-01

    This article considers how historians might use imagery in the context of an open-air school in Germany, Senne I-Bielefeld (1922-1939). In considering the "nature" of such images, issues and problems associated with their interpretation are illuminated and discussed. First, two images selected from the pre-Nazi period of the school are…

  19. Global emissions of trace gases, particulate matter, and hazardous air pollutants from open burning of domestic waste

    EPA Science Inventory

    The open burning of waste, whether at individual residences, businesses, or dump sites, is a large source of air pollutants. These emissions, however, are not included in many current emission inventories used in chemistry and climate modeling applications. This paper presents th...

  20. 76 FR 13569 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revisions to the Open...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... to the Open Burning Regulations AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule... Commonwealth of Virginia. The revisions recodify the open burning regulations which are currently in...

  1. Open hardware, low cost, air quality stations for monitoring ozone in coastal area

    NASA Astrophysics Data System (ADS)

    Lima, Marco; Donzella, Davide; Pintus, Fabio; Fedi, Adriano; Ferrari, Daniele; Massabò, Marco

    2014-05-01

    Ozone concentrations in urban and coastal area are a great concern for citizens and, consequently regulator. In the last 20 years the Ozone concentration is almost doubled and it has attracted the public attention because of the well know harmful impacts on human health and biosphere in general. Official monitoring networks usually comprise high precision, high accuracy observation stations, usually managed by public administrations and environmental agency; unfortunately due to their high costs of installation and maintenance, the monitoring stations are relatively sparse. This kind of monitoring networks have been recognized to be unsuitable to effectively characterize the high variability of air quality, especially in areas where pollution sources are various and often not static. We present a prototype of a low cost station for air quality monitoring, specifically developed for complementing the official monitoring stations improving the representation of air quality spatial distribution. We focused on a semi-professional product that could guarantee the highest reliability at the lowest possible cost, supported by a consistent infrastructure for data management. We test two type of Ozone sensor electrochemical and metal oxide. This work is integrated in the ACRONET Paradigm ® project: an open-hardware platform strongly oriented on environmental monitoring. All software and hardware sources will be available on the web. Thus, a computer and a small amount of work tools will be sufficient to create new monitoring networks, with the only constraint to share all the data obtained. It will so possible to create a real "sensing community". The prototype is currently able to measure ozone level, temperature and relative humidity, but soon, with the upcoming changes, it will be able also to monitor dust, carbon monoxide and nitrogen dioxide, always through the use of commercial sensors. The sensors are grouped in a compact board that interfaces with a data

  2. Dating the Lower Paleolithic Open-Air Site of Holon, Israel by Luminescence and ESR Techniques

    NASA Astrophysics Data System (ADS)

    Porat, Naomi; Zhou, Li Ping; Chazan, Michael; Noy, Tamar; Horwitz, Liora Kolska

    1999-05-01

    The open-air Acheulian site in Holon, Israel, was dated by the luminescence methods and by electron spin resonance (ESR). Situated in the coastal plain Quaternary Kurkar Group, the Holon site was first excavated in the late 1960s, when typical lower Paleolithic lithics and middle Pleistocene fauna were found. In order to date the site, new test pits were dug adjacent to the earlier excavations and the archaeological bed was exposed in a section comprising a series of paleosols and aeolianites. Alkali feldspars separated from the sediments were dated using the infrared stimulated luminescence and thermoluminescence signals, and quartz was dated using the optically stimulated luminescence signal. The age of the archaeological bed is constrained by two samples to 198,000 ± 22,000-201,000 ± 17,000 yr. The age of the base of the section is 240,000 ± 29,000 yr, and the age of the top is 81,000 ± 8000 yr. Two teeth from the archaeological bed, recovered from the original excavation collection, yielded an average ESR age of 204,000 ± 16,000 yr, calculated using the linear uptake model, which is in a very good agreement with the luminescence ages. These dates place Holon within the range of other late Acheulian and Acheulo-Yabrudian sites in this region such as Tabun E (younger chronology), Yabrud I (archaeological level 18), and Berekhat Ram.

  3. Open air biocathode enables effective electricity generation with microbial fuel cells.

    PubMed

    Clauwaert, Peter; Van der Ha, David; Boon, Nico; Verbeken, Kim; Verhaege, Marc; Rabaey, Korneel; Verstraete, Willy

    2007-11-01

    The reduction of oxygen at the cathode is one of the major bottlenecks of microbial fuel cells (MFCs). While research so far has mainly focused on chemical catalysis of this oxygen reduction, here we present a continuously wetted cathode with microorganisms that act as biocatalysts for oxygen reduction. We combined the anode of an acetate oxidizing tubular microbial fuel cell with an open air biocathode for electricity production. The maximum power production was 83 +/- 11 W m(-3) MFC (0.183 L MFC) for batch-fed systems (20-40% Coulombic yield) and 65 +/- 5 W m(-3) MFC for a continuous system with an acetate loading rate of 1.5 kg COD m(-3) day(-1) (90 +/- 3% Coulombic yield). Electrochemical precipitation of manganese oxides on the cathodic graphite felt decreased the start-up period with approximately 30% versus a non-treated graphite felt. After the start-up period, the cell performance was similar for the pretreated and non-treated cathodic electrodes. Several reactor designs were tested, and it was found that enlargement of the 0.183 L MFC reactor by a factor 2.9-3.8 reduced the volumetric power output by 60-67%. Biocathodes alleviate the need to use noble or non-noble catalysts for the reduction of oxygen, which increases substantially the viability and sustainability of MFCs.

  4. Water temperature of streams in the Cook Inlet basin, Alaska, and implications of climate change

    USGS Publications Warehouse

    Kyle, Rebecca E.; Brabets, Timothy P.

    2001-10-02

    Water-temperature data from 32 sites in the Cook Inlet Basin, south-central Alaska, indicate various trends that depend on watershed characteristics. Basins with 25 percent or more of their area consisting of glaciers have the coldest water temperatures during the open-water season, mid-May to mid-October. Streams and rivers that drain lowlands have the warmest water temperatures. A model that uses air temperature as input to predict water temperature as output was utilized to simulate future trends in water temperature based on increased air temperatures due to climate warming. Based on the Nash-Sutcliffe coefficient, the model produced acceptable results for 27 sites. For basins with more than 25 percent glacial coverage, the model was not as accurate. Results indicate that 15 sites had a predicted water-temperature change of 3 degrees Celsius or more, a magnitude of change that is considered significant for the incidence of disease in fish populations.

  5. TBCC Inlet Experiments and Analysis

    NASA Technical Reports Server (NTRS)

    Saunders, Dave; Slater, John; Dippold, Vance; Lee, Jinho; Sanders, Bobby; Weir, Lois

    2007-01-01

    A research plan is being implemented at NASA to investigate inlet mode transition for turbine-based combined-cycle (TBCC) propulsion for the hypersonic community. Unresolved issues have remained on how to design an inlet system to supply both a turbine engine and a ram/scramjet flowpath that operate with both high performance and stability. The current plan is aimed at characterizing the design, performance and operability of TBCC inlets through a series of experiments and analyses. A TBCC inlet has been designed that is capable of high performance (near MIL-E-5008B recovery) with smooth transitioning characteristics. Traditional design techniques were used in an innovative approach to balance the aerodynamic and mechanical constraints to create a new TBCC inlet concept. The inlet was designed for top-end Mach 7 scramjet speeds with an over/under turbine that becomes cocooned beyond its Mach 4 peak design point. Conceptually, this propulsion system was picked to meet the needs of the first stage of a two-stage to orbit vehicle. A series of increasing fidelity CFD-based tools are being used throughout this effort. A small-scale inlet experiment is on-going in the GRC 1'x1' Supersonic Wind Tunnel (SWT). Initial results from both the CFD analyses and test are discussed showing that high performance and smooth mode transitions are possible. The effort validates the design and is contributing to a large-scale inlet/propulsion test being planned for the GRC 10' x10' SWT. This large-scale effort provide the basis for a Combined Cycle Engine Testbed, (CCET), that will be able to address integrated propulsion system and controls objectives.

  6. Optimization and investigation of the effect of velocity distribution of air curtains on the performance of food refrigerated display cabinets

    NASA Astrophysics Data System (ADS)

    Wu, XueHong; Chang, ZhiJuan; Ma, QiuYang; Lu, YanLi; Yin, XueMei

    2016-08-01

    This paper focuses on improving the performance of the vertical open refrigerated display cabinets (VORDC) by optimizing the structure of deflector, which is affected by inlet velocity and velocity distribution of air curtains. The results show that the temperature of products located at the front and at the rear reduces as the increases of inlet velocity of air curtains. The increase of the inlet velocity of air curtains can strengthen the disturbance inside the VORDC, and also decrease the temperature of products inside the VORDC; the increase of the outer velocity of air curtain will exacerbate the disturbance outside the VORDC and decrease air curtain's performance. The present study can provide a theoretical foundation for the design of VORDC.

  7. Atheroembolization and potential air embolization during aortic declamping in open repair of a pararenal aortic aneurysm: A case report

    PubMed Central

    Dregelid, Einar Børre; Lilleng, Peer Kåre

    2016-01-01

    Introduction When ischemic events ascribable to microembolization occur during open repair of proximal abdominal aortic aneurysms, a likely origin of atheroembolism is not always found. Presentation of case A 78-year old man with enlargement of the entire aorta underwent open repair for a pararenal abdominal aortic aneurysm using supraceliac aortic clamping for 20 min. Then the graft was clamped, the supraceliac clamp was removed, and the distal and right renal anastomoses were also completed. The patient was stable throughout the operation with only transient drop in blood pressure on reperfusion. Postoperatively the patient developed ischemia, attributable to microembolization, in legs, small intestine, gall bladder and kidneys. He underwent fasciotomy, small bowel and gall bladder resections. Intestinal absorptive function did not recover adequately and he died after 4 months. Microscopic examination of hundreds of intestinal, juxtaintestinal mesenteric, and gall bladder arteries showed a few ones containing cholesterol emboli. Discussion It is unsure whether a few occluded small arteries out of several hundred could have caused the ischemic injury alone. There had been only moderate backbleeding from aortic branches above the proximal anastomosis while it was sutured. Inadvertently, remaining air in the graft, aorta, and aortic branches may have been whipped into the pulsating blood, resulting in air microbubbles, when the aortic clamp was removed. Conclusion Although both atheromatous particles and air microbubbles are well-known causes of iatrogenic microembolization, the importance of air microembolization in open repair of pararenal aortic aneurysms is not known and need to be studied. PMID:27100956

  8. Investigation of Aerodynamic and Icing Characteristics of Water-Inertia-Separation Inlets for Turbojet Engines

    NASA Technical Reports Server (NTRS)

    VonGlahn, Uwe; Blatz, R. E.

    1950-01-01

    The results of an investigation of several internal water-inertia-separation inlets consisting of a main duct and an alternate duct designed to prevent automatically the entrance of large quantities of water into a turbojet engine in icing conditions are presented. Total-pressure losses and icing characteristics for a direct-ram inlet and the inertia-separation inlets are compared at similar aerodynamic and simulated icing conditions. Complete ice protection for inlet guide vanes could not be achieved with the inertia-separation inlets investigated. Approximately 8 percent of the volume of water entering the nacelles remained. In the air passing into the compressor inlet. Heavy alternate-duct-elbow ice formations caused by secondary inertia separation resulted in rapid total-pressure losses and decreases in mass flow. The duration in an icing condition for an inertia-separation- inlet, without local surface heating, was increased approximately four times above that for a direct-ram inlet with a compressor-inlet screen. For normal nonicing operation, the inertia-separation- inlet total-pressure losses were comparable to a direct-ram installation. The pressure losses and the circumferential uniformity of the mass flow in all the inlets were relatively independent of angle of attack. Use of an inertia-separation inlet would in most cases require a larger diameter nacelle than a direct-ram inlet in order to obtain an alternate duct sufficiently large to pass the required engine air flow at duct Mach numbers below 1.0 at the minimum area.

  9. Experimental Evaluation of Pool Fire Suppression Performance of Sodium Leak Collection Tray in Open Air

    SciTech Connect

    Parida, F.C.; Rao, P.M.; Ramesh, S.S.; Malarvizhi, B.; Gopalakrishnan, V.; Rao, E.H.V.M.; Kasinathan, N.; Kannan, S.E.

    2006-07-01

    In the event of sodium leakage from heat transfer circuits of fast breeder reactors (FBR), liquid sodium catches fire in ambient air leading to production of flame, smoke and heat. One of the passive fire protection methods involves immediate collection of the leaking sodium to a sodium hold-up vessel (SHV) covered with a sloping cover tray (SCT) having a few drain pipes and one vent pipe (as in Fig. 1). As soon as the liquid sodium falls on the sloping cover tray, gravity guides the sodium through drain pipes into the bottom tray in which self-extinction occurs due to oxygen starvation. This sodium fire protection equipment called leak collection tray (LCT) works without the intervention of an operator and external power source. A large number of LCTs are strategically arranged under the sodium circulating pipe lines in the FBR plants to serve as passive suppression devices. In order to test the efficacy of the LCT, four tests were conducted. Two tests were with LCT having three drain pipes and rest with one. In each experiment, nearly 40 kg of hot liquid sodium at 550 deg. C was discharged on the LCT in the open air. Continuous on-line monitoring of temperature at strategic locations ({approx} 28 points) were carried out. Colour video-graphy was employed for taking motion pictures of various time-dependent events like sodium dumping, appearance of flame and release of smoke through vent pipes. After self-extinction of sodium fire, the LCT was allowed to cool overnight in an argon atmosphere. Solid samples of sodium debris in the SCT and SHV were collected by manual core drilling machine. The samples were subjected to chemical analysis for determination of unburnt and burnt sodium. The results of the four tests revealed an interesting feature: LCT with three drain pipes showed far lower sodium collection efficiency and much higher sodium combustion than that with just one drain pipe. Thermal fluctuations in temperature sensor located near the tip of the drain pipe

  10. DESIGN AND PERFORMANCE OF A LOW FLOW RATE INLET

    EPA Science Inventory

    Several ambient air samplers that have been designated by the U. S. EPA as Federal Reference Methods (FRMs) for measuring particulate matter nominally less than 10 um (PM10) include the use of a particular inlet design that aspirates particulate matter from the atmosphere at 1...

  11. Shock position sensor for supersonic inlets. [measuring pressure in the throat of a supersonic inlet

    NASA Technical Reports Server (NTRS)

    Dustin, M. O. (Inventor)

    1975-01-01

    Static pressure taps or ports are provided in the throat of a supersonic inlet, and signals indicative of the pressure at each of the ports is fed to respective comparators. Means are also provided for directing a signal indicative of the total throat pressure to the comparators. A periodic signal is superimposed on the total throat pressure so that the signal from the static pressure tabs is compared to a varying scan signal rather than to total throat pressure only. This type of comparison causes each comparator to provide a pulse width modulated output which may vary from 0% 'time on' to 100% 'time on'. The pulse width modulated outputs of the comparators are summed, filtered, and directed to a controller which operates a bypass valve such as a door whereby air is dumped from the inlet to prevent the shock wave from being expelled out the front.

  12. Sensitivity of rainfall-runoff processes in the Hydrological Open Air Laboratory

    NASA Astrophysics Data System (ADS)

    Széles, Borbála; Parajka, Juraj; Blöschl, Günter; Oismüller, Markus; Hajnal, Géza

    2016-04-01

    The objective of the present study was to simulate the rainfall response and analyse the sensitivity of rainfall-runoff processes of the Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, a small experimental watershed (66 ha) located in the western part of Lower Austria and dominated by agricultural land use. Due to the extensive monitoring network in the HOAL, the spatial and temporal heterogeneity of hydro-meteorological elements are exceptionally well represented on the catchment scale. The study aimed to exploit the facilities of the available database collected by innovative sensing techniques to advance the understanding of various rainfall-runoff processes. The TUWmodel, a lumped, conceptual hydrological model, following the structure of the HBV model was implemented on the catchment. In addition to the surface runoff at the catchment outlet, several different runoff generation mechanisms (tile drainage flow, saturation excess runoff from wetlands and groundwater discharge from springs) were also simulated, which gave an opportunity to describe the spatial distribution of model parameters in the study area. This helped to proceed from the original lumped model concept towards a spatially distributed one. The other focus of this work was to distinguish the dominant model parameters from the less sensitive ones for each tributary with different runoff type by applying two different sensitivity analysis methods, the simple local perturbation and the global Latin-Hypercube-One-Factor-At-a-Time (LH-OAT) tools. Moreover, the impacts of modifying the initial parameters of the LH-OAT method and the applied objective functions were also taken into consideration. The results and findings of the model and sensitivity analyses were summarized and future development perspectives were outlined. Key words: spatial heterogeneity of rainfall-runoff mechanisms, sensitivity analysis, lumped conceptual hydrological model

  13. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  14. Influence of cathode opening size and wetting properties of diffusion layers on the performance of air-breathing PEMFCs

    NASA Astrophysics Data System (ADS)

    Schmitz, A.; Tranitz, M.; Eccarius, S.; Weil, A.; Hebling, C.

    Air-breathing PEMFCs consist of an open cathodic side to allow an entirely passive supply of oxygen by diffusion. Furthermore, a large fraction of the produced water is removed by evaporation from the open cathode. Gas diffusion layers (GDLs) and the opening size of the cathode have a crucial influence on the performance of an air-breathing PEMFC. In order to assure an unobstructed supply of oxygen the water has to be removed efficiently and condensation in the GDL has to be avoided. On the other hand good humidification of the membrane has to be achieved to obtain high protonic conductivity. In this paper the influence of varying cathodic opening sizes (33%, 50% and 80% opening ratios) and of GDLs with different wetting properties are analysed. GDLs with hydrophobic and hydrophilic properties are prepared by coating of untreated GDLs (Toray ® carbon paper TGP-H-120, thickness of 350 μm). The air-breathing PEMFC test samples are realised using printed circuit board (PCB) technology. The cell samples were characterised over the entire potential range (0-0.95 V) by extensive measurements of the current density, the temperature and the cell impedance at 1 kHz. Additionally, measurements of the water balance were carried out at distinct operation points. The best cell performance was achieved with the largest opening ratio (80%) and an untreated GDL. At the maximum power point, this cell sample achieved a power density of 100 mW cm -2 at a moderate cell temperature of 43 °C. Furthermore, it could be shown that GDLs with hydrophilic or intense hydrophobic properties do not improve the performance of an air-breathing PEMFC. Based on the extensive characterisations, two design rules for air-breathing PEMFCs could be formulated. Firstly, it is crucial to maximise the cathode opening as far as an appropriate compression pressure of the cell assembly and therewith low contact resistance can be assured. Secondly, it is advantageous to use an untreated, slightly hydrophobic

  15. 77 FR 420 - Drawbridge Operation Regulation; Corson Inlet, Stathmere, NJ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-05

    ... deviation is necessary to facilitate the replacement of the steel railing. This deviation restricts operation of the draw span; no openings will be allowed during the course of the project, while the railings... south through Townsends Inlet. Though the span will be closed for the project, the 15 feet of...

  16. 76 FR 13511 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revisions to the Open...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... Prohibitions......... 5-40-5620 5-130-30 Permissible Open Burning 5-40-5630 5-130-40 ] Forest Management and... to the Open Burning Regulations AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final... Implementation Plan (SIP). The revisions recodify the open burning regulations which are currently in...

  17. Development of open air silicon deposition technology by silane-free atmospheric pressure plasma enhanced chemical transport under local ambient gas control

    NASA Astrophysics Data System (ADS)

    Naito, Teruki; Konno, Nobuaki; Yoshida, Yukihisa

    2016-07-01

    Open air silicon deposition was performed by combining silane-free atmospheric pressure plasma-enhanced chemical transport and a newly developed local ambient gas control technology. The effect of air contamination on silicon deposition was investigated using a vacuum chamber, and the allowable air contamination level was confirmed to be 3 ppm. The capability of the local ambient gas control head was investigated numerically and experimentally. A safe and clean process environment with air contamination less than 1 ppm was achieved. Combining these technologies, a microcrystalline silicon film was deposited in open air, the properties of which were comparable to those of silicon films deposited in a vacuum chamber.

  18. Closed circuit cardiopulmonary bypass with centrifugal pump for open-heart surgery: new trial for air removal.

    PubMed

    Morita, M; Yozu, R; Matayoshi, T; Mitsumaru, A; Shin, H; Kawada, S

    2000-06-01

    The purpose of this study is to examine the efficiency of venous air removal with a new cardiopulmonary bypass (CPB) circuit design for conventional open-heart surgeries. A main concern with a closed circuit for open-heart surgeries is air entrainment into the venous line. A venous filter was placed proximal to the centrifugal pump. The circuit proximal to the centrifugal pump was divided into two lines; one line was attached to the venous reservoir outlet. By clamping the line to the reservoir, this circuit becomes closed. Negative pressure was applied to the purge line connected to the venous reservoir for venous air removal. Micro bubbles were measured at two locations, both distal to the venous and arterial filters. When the injection rate reached 100 ml/min, with the air-injection over 30 s, micro bubbles greater than 40 micro were observed at the outlet of venous filter. However, there was no micro bubble greater than 40 micro detected at the outlet of arterial filter. Although micro bubbles greater than 40 micro were not detected at the outlet of the arterial filter up to the injection rate of 300 ml/min, when the injection rate reached 400 ml/min, micro bubbles greater than 50 microm were detected distal to the arterial filter. From this examination, we determined that air entrained in the venous line up to approximately 300 ml/min is automatically removed by this method with the pressure-balanced condition. This pressure balance means that resistance of venous return, gravity siphon, negative pressure by centrifugal pump, and negative pressure applied to the air-purge line of the filter are balanced; that is, the venous return is sufficient, and the venous reservoir volume is kept stable. From this study we determined that this circuit design efficiently removes the entrained air in the venous line.

  19. Design and Analysis Tools for Supersonic Inlets

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Folk, Thomas C.

    2009-01-01

    Computational tools are being developed for the design and analysis of supersonic inlets. The objective is to update existing tools and provide design and low-order aerodynamic analysis capability for advanced inlet concepts. The Inlet Tools effort includes aspects of creating an electronic database of inlet design information, a document describing inlet design and analysis methods, a geometry model for describing the shape of inlets, and computer tools that implement the geometry model and methods. The geometry model has a set of basic inlet shapes that include pitot, two-dimensional, axisymmetric, and stream-traced inlet shapes. The inlet model divides the inlet flow field into parts that facilitate the design and analysis methods. The inlet geometry model constructs the inlet surfaces through the generation and transformation of planar entities based on key inlet design factors. Future efforts will focus on developing the inlet geometry model, the inlet design and analysis methods, a Fortran 95 code to implement the model and methods. Other computational platforms, such as Java, will also be explored.

  20. Low speed test of the aft inlet designed for a tandem fan V/STOL nacelle

    NASA Technical Reports Server (NTRS)

    Rhoades, W. W.; Ybarra, A. H.

    1980-01-01

    An approximately .25 scale model of a Tandem Fan nacelle designed for a Type A V/STOL aircraft configuration was tested in a 10-by-10 foot wind tunnel. A 12 inch, tip driven, turbofan simulator was used to provide the suction source for the aft fan inlet. The front fan inlet was faired over for this test entry. Model variables consisted of a long aft inlet cowl, a short aft inlet cowl, a shaft simulator, blow-in door passages and diffuser vortex generators. Inlet pressure recovery, distortion, inlet angle of attack separation limits were evaluated at tunnel velocities from 0 to 240 knots, angles of attack from -10 to 40 degrees and inlet flow rates representative of throat Mach numbers of 0.1 to 0.6. High inlet performance and stable operation was verified at all design forward speed and angle of attack conditions. The short aft inlet configuration provided exceptionally high pressure recovery except at the highest combination of angle of attack and forward speed. The flow quality at the fan face was somewhat degraded by the addition of blow-in door passages to the long aft inlet configuration due to the pressure disturbances generated by the flow entering the diffuser through the auxiliary air passages.

  1. Mask-Free Patterning of High-Conductivity Metal Nanowires in Open Air by Spatially Modulated Femtosecond Laser Pulses.

    PubMed

    Wang, Andong; Jiang, Lan; Li, Xiaowei; Liu, Yang; Dong, Xianzi; Qu, Liangti; Duan, Xuanming; Lu, Yongfeng

    2015-10-28

    A novel high-resolution nanowire fabrication method is developed by thin-film patterning using a spatially modulated femtosecond laser pulse. Deep subwavelength (≈1/13 of the laser wavelength) and high conductivity (≈1/4 of the bulk gold) nanowires are fabricated in the open air without using masks, which offers a single-step arbitrary direct patterning approach for electronics, plasmonics, and optoelectronics nanodevices.

  2. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, F.W.; Kartsounes, G.T.

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air presure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  3. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, Frederick W.; Kartsounes, George T.

    1980-01-01

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air pressure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  4. A comparative study of the decomposition of pig carcasses in a methyl methacrylate box and open air conditions.

    PubMed

    Li, Liangliang; Wang, Jiangfeng; Wang, Yu

    2016-08-01

    Analysis of the process of decomposition is essential in establishing the postmortem interval. However, despite the fact that insects are important players in body decomposition, their exact function within the decay process is still unclear. There is also limited knowledge as to how the decomposition process occurs in the absence of insects. In the present study, we compared the decomposition of a pig carcass in open air with that of one placed in a methyl methacrylate box to prevent insect contact. The pig carcass in the methyl methacrylate box was in the fresh stage for 1 day, the bloated stage from 2 d to 11 d, and underwent deflated decay from 12 d. In contrast, the pig carcass in open air went through the fresh, bloated, active decay and post-decay stages; and 22.3 h (0.93 d), 62.47 h (2.60 d), 123.63 h (5.15 d) and 246.5 h (10.27 d) following the start of the experiment respectively, prior to entering the skeletonization stage. A large amount of soft tissue were remained on the pig carcass in the methyl methacrylate box on 26 d, while only scattered bones remained on the pig carcass in open air. The results indicate that insects greatly accelerate the decomposition process.

  5. Towards Estimating the Nutrient Balance of the Hydrologic Open Air Laboratory (HOAL) Catchment, Lower Austria

    NASA Astrophysics Data System (ADS)

    Exner-Kittridge, Michael; Zessner, Matthias; Broer, Martine; Eder, Alexander; Strauss, Peter; Blöschl, Günter

    2010-05-01

    The fate of nutrients introduced by human activities have significant impacts on both nature and our civilization. Excessive nutrients can contaminate our drinking water as well as promote algae blooms that deplete the surrounding waters of oxygen for aquatic life. It is estimated that agriculture in Austria contributes approximately 60% to the total discharge of nitrogen and 40% to the total discharge of phosphorus. Understanding the specific pathways and sources of nitrogen and phosphorus from agriculture land could greatly improve our ability to mitigate for excessive discharges if the problems can be targeted more precisely. The objective of our research is to determine the complete nitrogen and phosphorous balance within a 66.7 hectare catchment in Lower Austria. The Hydrologic Open Air Laboratory (HOAL) catchment is located in Lower Austria approximately 100 km west of Vienna. The HOAL catchment was established in 2009 through funding by the Austrian Science Foundation to be used for multidisciplinary hydrologic research for understanding water flow and transport processes in catchments. The catchment land cover is characterized as 90% agriculture, 5% impermeable surface, and 3% forest. The predominant soil type is a clayey silt loam and a section of the catchment contain a subsurface tile drainage network that extend approximately 5.5 km. Nitrogen and phosphorus are the two primary nutrients assessed in this study. To accomplish the nutrient balance, the research is divided into three different scales: Field Scale, Subcatchment Scale, and Catchment Scale. The Catchment scale encompasses the entirety of the catchment, the subcatchment scale encompasses a 6.4 hectare area within the catchment that is completely underlain by the tile drainage network, and the field scale studies are performed on several square meter plots within the subcatchment. Each scale attempts to determine different parts of the total nutrient budget. The initial phase of the research

  6. The Hydrological Open Air Laboratory (HOAL) in Petzenkirchen: a hypothesis-driven observatory

    NASA Astrophysics Data System (ADS)

    Blöschl, G.; Blaschke, A. P.; Broer, M.; Bucher, C.; Carr, G.; Chen, X.; Eder, A.; Exner-Kittridge, M.; Farnleitner, A.; Flores-Orozco, A.; Haas, P.; Hogan, P.; Kazemi Amiri, A.; Oismüller, M.; Parajka, J.; Silasari, R.; Stadler, P.; Strauss, P.; Vreugdenhil, M.; Wagner, W.; Zessner, M.

    2016-01-01

    Hydrological observatories bear a lot of resemblance to the more traditional research catchment concept, but tend to differ in providing more long-term facilities that transcend the lifetime of individual projects, are more strongly geared towards performing interdisciplinary research, and are often designed as networks to assist in performing collaborative science. This paper illustrates how the experimental and monitoring set-up of an observatory, the 66 ha Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, Lower Austria, has been established in a way that allows meaningful hypothesis testing. The overarching science questions guided site selection, identification of dissertation topics and the base monitoring. The specific hypotheses guided the dedicated monitoring and sampling, individual experiments, and repeated experiments with controlled boundary conditions. The purpose of the HOAL is to advance the understanding of water-related flow and transport processes involving sediments, nutrients and microbes in small catchments. The HOAL catchment is ideally suited for this purpose, because it features a range of different runoff generation processes (surface runoff, springs, tile drains, wetlands), the nutrient inputs are known, and it is convenient from a logistic point of view as all instruments can be connected to the power grid and a high-speed glassfibre local area network (LAN). The multitude of runoff generation mechanisms in the catchment provides a genuine laboratory where hypotheses of flow and transport can be tested, either by controlled experiments or by contrasting sub-regions of different characteristics. This diversity also ensures that the HOAL is representative of a range of catchments around the world, and the specific process findings from the HOAL are applicable to a variety of agricultural catchment settings. The HOAL is operated jointly by the Vienna University of Technology and the Federal Agency for Water Management and takes

  7. The Hydrological Open Air Laboratory (HOAL) in Petzenkirchen: a hypotheses driven observatory

    NASA Astrophysics Data System (ADS)

    Blöschl, G.; Blaschke, A. P.; Broer, M.; Bucher, C.; Carr, G.; Chen, X.; Eder, A.; Exner-Kittridge, M.; Farnleitner, A.; Flores-Orozco, A.; Haas, P.; Hogan, P.; Kazemi Amiri, A.; Oismüller, M.; Parajka, J.; Silasari, R.; Stadler, P.; Strauß, P.; Vreugdenhil, M.; Wagner, W.; Zessner, M.

    2015-07-01

    Hydrological observatories bear a lot of resemblance to the more traditional research catchment concept but tend to differ in providing more long term facilities that transcend the lifetime of individual projects, are more strongly geared towards performing interdisciplinary research, and are often designed as networks to assist in performing collaborative science. This paper illustrates how the experimental and monitoring setup of an observatory, the 66 ha Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, Lower Austria, has been established in a way that allows meaningful hypothesis testing. The overarching science questions guided site selection, identifying dissertation topics and the base monitoring. The specific hypotheses guided the dedicated monitoring and sampling, individual experiments, and repeated experiments with controlled boundary conditions. The purpose of the HOAL is to advance the understanding of water related flow and transport processes involving sediments, nutrients and microbes in small catchments. The HOAL catchment is ideally suited for this purpose, because it features a range of different runoff generation processes (surface runoff, springs, tile drains, wetlands), the nutrient inputs are known, and it is convenient from a logistic point of view as all instruments can be connected to the power grid and a high speed glassfibre Local Area Network. The multitude of runoff generation mechanisms in the catchment provide a genuine laboratory where hypotheses of flow and transport can be tested, either by controlled experiments or by contrasting sub-regions of different characteristics. This diversity also ensures that the HOAL is representative of a range of catchments around the world and the specific process findings from the HOAL are applicable to a variety of agricultural catchment settings. The HOAL is operated jointly by the Vienna University of Technology and the Federal Agency for Water Management and takes advantage of the

  8. Analysis of an advanced ducted propeller subsonic inlet

    NASA Technical Reports Server (NTRS)

    Iek, Chanthy; Boldman, Donald R.; Ibrahim, Mounir

    1992-01-01

    A time marching Navier-Stokes code called PARC (PARC2D for 2-D/axisymmetric and PARC3D for 3-D flow simulations) was validated for an advanced ducted propeller (ADP) subsonic inlet. The code validation for an advanced ducted propeller (ADP) subsonic inlet. The code validation was implemented for a non-separated flow condition associated with the inlet operating at angles-of-attack of 0 and 25 degrees. The inlet test data were obtained in the 9 x 15 ft Low Speed Wind Tunnel at NASA Lewis Research Center as part of a cooperative study with Pratt and Whitney. The experimental study focused on the ADP inlet performance for take-off and approach conditions. The inlet was tested at a free stream Mach number of 0.2, at angles-of-attack between O and 35 degrees, and at a maximum propeller speed of 12,000 RPM which induced a corrected air flow rate of about 46 lb/sec based on standard day conditions. The computational grid and flow boundary conditions (BC) were based on the actual inlet geometry and the funnel flow conditions. At the propeller face, two types of BC's were applied: a mass flow BC and a fixed flow properties BC. The fixed flow properties BC was based on a combination of data obtained from the experiment and calculations using a potential flow code. Comparison of the computational results with the test data indicates that the PARC code with the propeller face fixed flow properties BC provided a better prediction of the inlet surface static pressures than the predictions when the mass flow BC was used. For an angle-of-attack of 0 degrees, the PARC2D code with the propeller face mass flow BC provided a good prediction of inlet static pressures except in the region of high pressure gradient. With the propeller face fixed flow properties BC, the PARC2D code provided a good prediction of the inlet static pressures. For an angle-of-attack of 25 degrees with the mass flow BC, the PARC3D code predicted statis pressures which deviated significantly from the test data

  9. A decision support tool for evaluating the air quality and wind comfort induced by different opening configurations for buildings in canyons.

    PubMed

    Fan, M; Chau, C K; Chan, E H W; Jia, J

    2017-01-01

    This study formulated a new index for evaluating both the air quality and wind comfort induced by building openings at the pedestrian level of street canyons. The air pollutant concentrations and wind velocities induced by building openings were predicted by a series of CFD simulations using ANSYS Fluent software based on standard k-ɛ model. The types of opening configurations investigated inside isolated and non-isolated canyons included separations, voids and permeable elements. It was found that openings with permeability values of 10% were adequate for improving the air quality and wind comfort conditions for pedestrians after considering the reduction in development floor areas. Openings were effective in improving the air quality in isolated canyons and different types of opening configurations were suggested for different street aspect ratios. On the contrary, openings were not always found effective for non-isolated canyons if there were pollutant sources in adjacent street canyons. As such, it would also be recommended introducing openings to adjacent canyons along with openings to the target canyons. The formulated index can help city planners and building designers to strike an optimal balance between air quality and wind comfort for pedestrians when designing and planning buildings inside urban streets and thus promoting urban environmental sustainability.

  10. IPAC-Inlet Performance Analysis Code

    NASA Technical Reports Server (NTRS)

    Barnhart, Paul J.

    1997-01-01

    A series of analyses have been developed which permit the calculation of the performance of common inlet designs. The methods presented are useful for determining the inlet weight flows, total pressure recovery, and aerodynamic drag coefficients for given inlet geometric designs. Limited geometric input data is required to use this inlet performance prediction methodology. The analyses presented here may also be used to perform inlet preliminary design studies. The calculated inlet performance parameters may be used in subsequent engine cycle analyses or installed engine performance calculations for existing uninstalled engine data.

  11. Centrifugal pump inlet pressure site affects measurement.

    PubMed

    Augustin, Simon; Horton, Alison; Butt, Warwick; Bennett, Martin; Horton, Stephen

    2010-09-01

    During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length.

  12. Method for Determining Optimum Injector Inlet Geometry

    NASA Technical Reports Server (NTRS)

    Trinh, Huu P. (Inventor); Myers, W. Neill (Inventor)

    2015-01-01

    A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

  13. Optical and RF electrical characteristics of atmospheric pressure open-air hollow slot microplasmas and application to bacterial inactivation

    NASA Astrophysics Data System (ADS)

    Rahul, R.; Stan, O.; Rahman, A.; Littlefield, E.; Hoshimiya, K.; Yalin, A. P.; Sharma, A.; Pruden, A.; Moore, C. A.; Yu, Z.; Collins, G. J.

    2005-06-01

    We report electrical properties of radio frequency (RF)-driven hollow slot microplasmas operating in open air but with uniform luminous discharges at RF current densities of the order of A cm-2. We employ interelectrode separations of 100-600 µm to achieve this open-air operation but because the linear slot dimension of our electrode designs are of extended length, we can achieve, for example, open-air slot shaped plasmas 30 cm in length. This creates a linear plasma source for wide area plasma driven surface treatment applications. RF voltages at frequencies of 4-60 MHz are applied to an interior electrode to both ignite and sustain the plasma between electrodes. The outer slotted electrode is grounded. Illustrative absolute emission of optical spectra from this source is presented in the region from 100 to 400 nm as well as total oxygen radical fluxes from the source. We present both RF breakdown and sustaining voltage measurements as well as impedance values measured for the microplasmas, which use flowing rare gas in the interelectrode region exiting into open air. The requirement for rare gas flow is necessary to get uniform plasmas of dimensions over 30 cm, but is a practical disadvantage. In one mode of operation we create an out-flowing afterglow plasma plume, which extends 1-3 mm from the grounded open slot allowing for treatment of work pieces placed millimetres away from the grounded electrode. This afterglow configuration also allows for lower gas temperatures impinging on substrates, than the use of active plasmas. Work pieces are not required to be part of any electrical circuit, bringing additional practical advantages. We present a crude lumped parameter equivalent circuit model to analyse the effects of changing RF sheaths with frequency of excitation and applied RF current to better understand the relative roles of sheath and bulk plasma behaviour observed in electrical characteristics. Estimates of the bulk plasma densities are also provided

  14. A dynamic thermal model for design and control of an 800-element open-air radio telescope

    NASA Astrophysics Data System (ADS)

    Bremer, Michael; Greve, Albert

    2011-09-01

    In earlier work we have described the thermal modelling for design and control of a fully insulated, and sometimes ventilated, high precision radio telescope. For such an insulated telescope the modelling of the time-variable dynamic influence of the thermal environment (air, sky and ground radiation, insolation) is relatively simple. The modelling becomes however quite complex for an open-air radio telescope where each individual member of the reflector backup structure (BUS) and the support structure (fork or yoke) is exposed under a different and time-dependent aspect angle to the thermal environment, which applies in particular to solar radiation. We present a time-dependent 800-element thermal model of an open-air telescope. Using the IRAM 30-m radio telescope as the basic mechanical structure, we explain how the temperature induced, real-time pointing and reflector surface deformations can be derived when using as input the day of the year, the thermal environment, and the geographic position of the telescope and its changing pointing direction. Thermal modelling and results similar to those reported here can be used for radio telescope design and real-time control of pointing and surface adjustment of a telescope with active panels.

  15. Carbon Dioxide Washout Testing Using Various Inlet Vent Configurations in the Mark-III Space Suit

    NASA Technical Reports Server (NTRS)

    Korona, F. Adam; Norcross, Jason; Conger, Bruce; Navarro, Moses

    2014-01-01

    Requirements for using a space suit during ground testing include providing adequate carbon dioxide (CO2) washout for the suited subject. Acute CO2 exposure can lead to symptoms including headache, dyspnea, lethargy, and eventually unconsciousness or even death. Symptoms depend on several factors including inspired partial pressure of CO2 (ppCO2), duration of exposure, metabolic rate of the subject, and physiological differences between subjects. Computational Fluid Dynamics (CFD) analysis has predicted that the configuration of the suit inlet vent has a significant effect on oronasal CO2 concentrations. The main objective of this test was to characterize inspired oronasal ppCO2 for a variety of inlet vent configurations in the Mark-III suit across a range of workload and flow rates. Data and trends observed during testing along with refined CFD models will be used to help design an inlet vent configuration for the Z-2 space suit. The testing methodology used in this test builds upon past CO2 washout testing performed on the Z-1 suit, Rear Entry I-Suit, and the Enhanced Mobility Advanced Crew Escape Suit. Three subjects performed two test sessions each in the Mark-III suit to allow for comparison between tests. Six different helmet inlet vent configurations were evaluated during each test session. Suit pressure was maintained at 4.3 psid. Suited test subjects walked on a treadmill to generate metabolic workloads of approximately 2000 and 3000 BTU/hr. Supply airflow rates of 6 and 4 actual cubic feet per minute were tested at each workload. Subjects wore an oronasal mask with an open port in front of the mouth and were allowed to breathe freely. Oronasal ppCO2 was monitored real-time via gas analyzers with sampling tubes connected to the oronasal mask. Metabolic rate was calculated from the CO2 production measured by an additional gas analyzer at the air outlet from the suit. Real-time metabolic rate measurements were used to adjust the treadmill workload to meet

  16. CO2 Washout Testing Using Various Inlet Vent Configurations in the Mark-III Space Suit

    NASA Technical Reports Server (NTRS)

    Korona, F. Adam; Norcross, Jason; Conger, Bruce; Navarro, Moses

    2014-01-01

    Requirements for using a space suit during ground testing include providing adequate carbon dioxide (CO2) washout for the suited subject. Acute CO2 exposure can lead to symptoms including headache, dyspnea, lethargy and eventually unconsciousness or even death. Symptoms depend on several factors including inspired partial pressure of CO2 (ppCO2), duration of exposure, metabolic rate of the subject and physiological differences between subjects. Computational Fluid Dynamic (CFD) analysis has predicted that the configuration of the suit inlet vent has a significant effect on oronasal CO2 concentrations. The main objective of this test is to characterize inspired oronasal ppCO2 for a variety of inlet vent configurations in the Mark-III space suit across a range of workload and flow rates. As a secondary objective, results will be compared to the predicted CO2 concentrations and used to refine existing CFD models. These CFD models will then be used to help design an inlet vent configuration for the Z-2 space suit, which maximizes oronasal CO2 washout. This test has not been completed, but is planned for January 2014. The results of this test will be incorporated into this paper. The testing methodology used in this test builds upon past CO2 washout testing performed on the Z-1 suit, Rear Entry I-Suit (REI) and the Enhanced Mobility Advanced Crew Escape Suit (EM-ACES). Three subjects will be tested in the Mark-III space suit with each subject performing two test sessions to allow for comparison between tests. Six different helmet inlet vent configurations will be evaluated during each test session. Suit pressure will be maintained at 4.3 psid. Subjects will wear the suit while walking on a treadmill to generate metabolic workloads of approximately 2000 and 3000 BTU/hr. Supply airflow rates of 6 and 4 actual cubic feet per minute (ACFM) will be tested at each workload. Subjects will wear an oronasal mask with an open port in front of the mouth and will be allowed to

  17. CO2 Washout Testing Using Various Inlet Vent Configurations in the Mark-III Space Suit

    NASA Technical Reports Server (NTRS)

    Korona, F. Adam; Norcross, Jason; Conger, Bruce; Navarro, Moses

    2014-01-01

    Requirements for using a space suit during ground testing include providing adequate carbon dioxide (CO2) washout for the suited subject. Acute CO2 exposure can lead to symptoms including headache, dyspnea, lethargy and eventually unconsciousness or even death. Symptoms depend on several factors including inspired partial pressure of CO2 (ppCO2), duration of exposure, metabolic rate of the subject and physiological differences between subjects. Computational Fluid Dynamic (CFD) analysis has predicted that the configuration of the suit inlet vent has a significant effect on oronasal CO2 concentrations. The main objective of this test was to characterize inspired oronasal ppCO2 for a variety of inlet vent configurations in the Mark-III suit across a range of workload and flow rates. Data and trends observed during testing along with refined CFD models will be used to help design an inlet vent configuration for the Z-2 space suit. The testing methodology used in this test builds upon past CO2 washout testing performed on the Z-1 suit, Rear Entry I-Suit (REI) and the Enhanced Mobility Advanced Crew Escape Suit (EM-ACES). Three subjects performed two test sessions each in the Mark-III suit to allow for comparison between tests. Six different helmet inlet vent configurations were evaluated during each test session. Suit pressure was maintained at 4.3 psid. Suited test subjects walked on a treadmill to generate metabolic workloads of approximately 2000 and 3000 BTU/hr. Supply airflow rates of 6 and 4 actual cubic feet per minute (ACFM) were tested at each workload. Subjects wore an oronasal mask with an open port in front of the mouth and were allowed to breathe freely. Oronasal ppCO2 was monitored real-time via gas analyzers with sampling tubes connected to the oronasal mask. Metabolic rate was calculated from the total oxygen consumption and CO2 production measured by additional gas analyzers at the air outlet from the suit. Realtime metabolic rate measurements were

  18. CO2 Washout Testing Using Various Inlet Vent Configurations in the Mark-III Space Suit

    NASA Technical Reports Server (NTRS)

    Korona, F. Adam; Norcross, Jason; Conger, Bruce; Navarro, Moses

    2014-01-01

    Requirements for using a space suit during ground testing include providing adequate carbon dioxide (CO2) washout for the suited subject. Acute CO2 exposure can lead to symptoms including headache, dyspnea, lethargy and eventually unconsciousness or even death. Symptoms depend on several factors including inspired partial pressure of CO2 (ppCO2), duration of exposure, metabolic rate of the subject and physiological differences between subjects. Computational Fluid Dynamic (CFD) analysis has predicted that the configuration of the suit inlet vent has a significant effect on oronasal CO2 concentrations. The main objective of this test was to characterize inspired oronasal ppCO2 for a variety of inlet vent configurations in the Mark-III suit across a range of workload and flow rates. Data and trends observed during testing along with refined CFD models will be used to help design an inlet vent configuration for the Z-2 space suit. The testing methodology used in this test builds upon past CO2 washout testing performed on the Z-1 suit, Rear Entry I-Suit (REI) and the Enhanced Mobility Advanced Crew Escape Suit (EM-ACES). Three subjects performed two test sessions each in the Mark-III suit to allow for comparison between tests. Six different helmet inlet vent configurations were evaluated during each test session. Suit pressure was maintained at 4.3 psid. Suited test subjects walked on a treadmill to generate metabolic workloads of approximately 2000 and 3000 BTU/hr. Supply airflow rates of 6 and 4 actual cubic feet per minute (ACFM) were tested at each workload. Subjects wore an oronasal mask with an open port in front of the mouth and were allowed to breathe freely. Oronasal ppCO2 was monitored real-time via gas analyzers with sampling tubes connected to the oronasal mask. Metabolic rate was calculated from the total oxygen consumption and CO2 production measured by additional gas analyzers at the air outlet from the suit. Real-time metabolic rate measurements were

  19. Open and Closed Loop Stability of Hingeless Rotor Helicopter Air and Ground Resonance

    NASA Technical Reports Server (NTRS)

    Young, M. I.; Bailey, D. J.; Hirschbein, M. S.

    1974-01-01

    The air and ground resonance instabilities of hingeless rotor helicopters are examined on a relatively broad parametric basis including the effects of blade tuning, virtual hinge locations, and blade hysteresis damping, as well as size and scale effects in the gross weight range from 5,000 to 48,000 pounds. A special case of a 72,000 pound helicopter air resonance instability is also included. The study shows that nominal to moderate and readily achieved levels of blade inertial hysteresis damping in conjunction with a variety of tuning and/or feedback conditions are highly effective in dealing with these instabilities. Tip weights and reductions in pre-coning angles are also shown to be effective means for improving the air resonance instability.

  20. Meeting Review: Airborne Aerosol Inlet Workshop

    NASA Technical Reports Server (NTRS)

    Baumgardner, Darrel; Huebert, Barry; Wilson, Chuck

    1991-01-01

    Proceedings from the Airborne Aerosol Inlet Workshop are presented. The two central topics of discussion were the role of aerosols in atmospheric processes and the difficulties in characterizing aerosols. The following topics were discussed during the working sessions: airborne observations to date; identification of inlet design issues; inlet modeling needs and directions; objectives for aircraft experiments; and future laboratory and wind tunnel studies.

  1. Low-power, open-path mobile sensing platform for high-resolution measurements of greenhouse gases and air pollutants

    NASA Astrophysics Data System (ADS)

    Tao, Lei; Sun, Kang; Miller, David J.; Pan, Dan; Golston, Levi M.; Zondlo, Mark A.

    2015-04-01

    A low-power mobile sensing platform has been developed with multiple open-path gas sensors to measure the ambient concentrations of greenhouse gases and air pollutants with high temporal and spatial resolutions over extensive spatial domains. The sensing system consists of four trace gas sensors including two custom quantum cascade laser-based open-path sensors and two LICOR open-path sensors to measure CO2, CO, CH4, N2O, NH3, and H2O mixing ratios simultaneously at 10 Hz. In addition, sensors for meteorological and geolocation data are incorporated into the system. The system is powered by car batteries with a low total power consumption (~200 W) and is easily transportable due to its low total mass (35 kg). Multiple measures have been taken to ensure robust performance of the custom, open-path sensors located on top of the vehicle where the optics are exposed to the harsh on-road environment. The mobile sensing system has been integrated and installed on top of common passenger vehicles and participated in extensive field campaigns (>400 h on-road time with >18,000 km total distance) in both the USA and China. The simultaneous detection of multiple trace gas species makes the mobile sensing platform a unique and powerful tool to identify and quantify different emission sources through mobile mapping.

  2. 30 CFR 75.507-1 - Electric equipment other than power-connection points; outby the last open crosscut; return air...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... other than power-connection points; outby the last open crosscut; return air; permissibility requirements. (a) All electric equipment, other than power-connection points, used in return air outby the last... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric equipment other than...

  3. Air Vehicle Technology Integration Program (AVTIP) Delivery Order 0015: Open Control Platform (OCP) Software Enabled Control (SEC) Hardware in the Loop Simulation - OCP Hardware Integration

    DTIC Science & Technology

    2005-06-01

    AFRL-VA-WP-TR-2006-3075 AIR VEHICLE TECHNOLOGY INTEGRATION PROGRAM (AVTIP) Delivery Order 0015: Open Control Platform (OCP) Software Enabled...2001– 05/28/2004 5a. CONTRACT NUMBER F33615-00-D-3052-0015 5b. GRANT NUMBER 4. TITLE AND SUBTITLE AIR VEHICLE TECHNOLOGY INTEGRATION PROGRAM

  4. Optimal control of a supersonic inlet to minimize frequency of inlet unstart

    NASA Technical Reports Server (NTRS)

    Lehtinen, B.; Zeller, J. R.; Geyser, L. C.

    1978-01-01

    A preliminary investigation into the use of modern control theory for the design of controls for a supersonic inlet is described. In particular, the task of controlling a mixed-compression supersonic inlet is formulated as a linear optimal stochastic control and estimation problem. An inlet can exhibit an undesirable instability due to excessive inlet normal shock motion. For the optimal control formulation of the inlet problem, a non quadratic performance index, which is equal to the expected frequency of inlet unstarts, is used. This physically meaningful performance index is minimized for a range of inlet disturbance and measurement noise covariances.

  5. An Inexpensive Autosampler to Maximize Throughput for an Ion Source that Samples Surfaces in Open Air

    EPA Science Inventory

    An autosampler was built to pull cotton swab heads mounted into a 3-foot long, square Al rod in ambient air through the He ionizing beam of a Direct Analysis in Real Time (DART) ion source interfaced to an orthogonal acceleration, time-of-flight mass spectrometer. The cost of th...

  6. THE EFFECT OF OPENING WINDOWS ON AIR CHANGE RATES IN TWO HOMES

    EPA Science Inventory

    Over 300 air change rate experiments were completed in two occupied residences: a two-story detached house in Redwood City, CA and a three-story townhouse in Reston, VA. A continuous monitor was used to measure the decay of sulfur hexafluoride tracer gas over periods of 1 to 1...

  7. CHARACTERIZATION OF AIR EMISSIONS FROM THE SIMULATED OPEN COMBUSTION OF FIBERGLASS MATERIALS

    EPA Science Inventory

    The report identifies and quantifies a broad range of pollutants that are discharged during small-scale, simulated, open combustion of fiberglass, and reports these emissions relative to the mass of fiberglass material combusted. Two types of fiberglass materials (representing t...

  8. Determination of fecal contamination origin in reclaimed water open-air ponds using biochemical fingerprinting of enterococci and fecal coliforms.

    PubMed

    Casanovas-Massana, Arnau; Blanch, Anicet R

    2013-05-01

    Low levels of fecal indicator bacteria (FIB) were recently detected in two reclaimed water open-air ponds used to irrigate a golf course located in Northeastern Spain. The aim of this study was to evaluate the feasibility of a biochemical fingerprinting method to track the origin of fecal contamination in water with low FIB levels, as in the aforementioned ponds. We also aimed to determine whether FIB presence was due to regrowth of the reclaimed water populations or to a contribution of fecal matter whose source was in the golf facility. Three hundred and fifty enterococcal strains and 308 fecal coliform strains were isolated from the ponds and reclamation plant, and they were biochemically phenotyped. In addition, the inactivation of several microbial fecal pollution indicators (fecal coliforms, total bifidobacteria, sorbitol-fermenting bifidobacteria, somatic bacteriophages, and bacteriophages infecting Bacteroides thetaiotaomicron) was studied using a mesocosm in situ in order to obtain information about their decay rate. Although FIB concentration was low, the biochemical fingerprinting provided evidence that the origin of the fecal contamination in the ponds was not related to the reclaimed water. Biochemical fingerprinting thus proved to be a successful approach, since other microbial source-tracking methods perform poorly when dealing with low fecal load matrices. Furthermore, the mesocosm assays indicated that none of the microbial fecal indicators was able to regrow in the ponds. Finally, the study highlights the fact that reclaimed water may be recontaminated in open-air reservoirs, and therefore, its microbial quality should be monitored throughout its use.

  9. The city model as a tool for participatory urban planning - a case study: The Bilotti open air museum of Cosenza

    NASA Astrophysics Data System (ADS)

    Artese, S.

    2014-05-01

    The paper describes the implementation of the 3D city model of the pedestrian area of Cosenza, which in recent years has become the Bilotti Open Air Museum (MAB). For this purpose were used both the data available (regional technical map, city maps, orthophotos) and acquired through several surveys of buildings and "Corso Mazzini" street (photos, topographic measurements, laser scanner point clouds). In addition to the urban scale model, the survey of the statues of the MAB was carried out. By means of data processing, the models of the same statues have been created, that can be used as objects within the city model. The 3D model of the MAB open air museum has been used to implement a Web-GIS allowing the citizen's participation, understanding and suggestions. The 3D city model is intended as a new tool for urban planning, therefore it has been used both for representing the current situation of the MAB and for design purposes, by acknowledging suggestions regarding a possible different location of the statues and a new way to enjoy the museum.

  10. Analysis of an open-air swimming pool solar heating system by using an experimentally validated TRNSYS model

    SciTech Connect

    Ruiz, Elisa; Martinez, Pedro J.

    2010-01-15

    In the case of private outdoor swimming pools, seldom larger than 100 m{sup 2}, conventional auxiliary heating systems are being installed less and less. Solar heating is an option to extend the swimming season. The temperature evolution of an open-air swimming pool highly depends on the wind speed directly on the water surface, which at the same time is influenced by the surroundings of the pool. In this paper, the TRNSYS model of a private open-air pool with a 50-m{sup 2} surface was validated by registering the water temperature evolution and the meteorological data at the pool site. Evaporation is the main component of energy loss in swimming pools. Six different sets of constants found in literature were considered to evaluate the evaporative heat transfer coefficient with the purpose of finding the most suitable one for the TRNSYS pool model. In order to do that, the evolution of the pool water temperature predicted by the TRNSYS pool model was compared with the experimentally registered one. The simulation with TRNSYS of the total system, including the swimming pool and the absorber circuit integrated into the existing filter circuit, provided information regarding the increase of the pool temperature for different collector areas during the swimming season. This knowledge, together with the economic costs, support the decision about the absorber field size. (author)

  11. Rise time reduction of thermal actuators operated in air and water through optimized pre-shaped open-loop driving

    NASA Astrophysics Data System (ADS)

    Larsen, T.; Doll, J. C.; Loizeau, F.; Hosseini, N.; Peng, A. W.; Fantner, G. E.; Ricci, A. J.; Pruitt, B. L.

    2017-04-01

    Electrothermal actuators have many advantages compared to other actuators used in micro-electro-mechanical systems (MEMS). They are simple to design, easy to fabricate and provide large displacements at low voltages. Low voltages enable less stringent passivation requirements for operation in liquid. Despite these advantages, thermal actuation is typically limited to a few kHz bandwidth when using step inputs due to its intrinsic thermal time constant. However, the use of pre-shaped input signals offers a route for reducing the rise time of these actuators by orders of magnitude. We started with an electrothermally actuated cantilever having an initial 10–90% rise time of 85 μs in air and 234 μs in water for a standard open-loop step input. We experimentally characterized the linearity and frequency response of the cantilever when operated in air and water, allowing us to obtain transfer functions for the two cases. We used these transfer functions, along with functions describing desired reduced rise-time system responses, to numerically simulate the required input signals. Using these pre-shaped input signals, we improved the open-loop 10–90% rise time from 85 μs to 3 μs in air and from 234 μs to 5 μs in water, an improvement by a factor of 28 and 47, respectively. Using this simple control strategy for MEMS electrothermal actuators makes them an attractive alternative to other high speed micromechanical actuators such as piezoelectric stacks or electrostatic comb structures which are more complex to design, fabricate, or operate.

  12. Characteristics of a Direct Current-driven plasma jet operated in open air

    SciTech Connect

    Li, Xuechen; Bao, Wenting; Di, Cong; Jia, Pengying

    2013-09-30

    A DC-driven plasma jet has been developed to generate a diffuse plasma plume by blowing argon into the ambient air. The plasma plume, showing a cup shape with a diameter of several centimeters at a higher voltage, is a pulsed discharge despite a DC voltage is applied. The pulse frequency is investigated as a function of the voltage under different gap widths and gas flow rates. Results show that plasma bullets propagate from the hollow needle to the plate electrode by spatially resolved measurement. A supposition about non-electroneutral trail of the streamer is proposed to interpret these experimental phenomena.

  13. DEA-I: A Globally Configurable Open Source Software Package in Support of Air Quality Forecasts

    NASA Astrophysics Data System (ADS)

    Davies, J.; Strabala, K.; Pierce, R.; Huang, H.; Schiffer, E.

    2012-12-01

    During September 2003, a team of NASA, NOAA, and EPA researchers demonstrated a prototype for using Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth retrievals in daily air quality forecasts; this became known as IDEA (Infusing satellite Data into Environmental Applications). IDEA was part of the NASA Applied Sciences Program strategy to demonstrate practical uses of NASA-sponsored observations from space and predictions. Following its successful demonstration an export version of IDEA, known as IDEA International (IDEA-I), has now been released. IDEA-I supports the Global Earth Observation Systems of Systems (GEOSS) Group on Earth Observations (GEO) Health Societal Benefit Area (SBA) and is being developed within the framework of the GEO Earth Observations in Decision Support Call for Proposals. The vehicle for IDEA-I release is the International MODIS and AIRS (Atmospheric Infrared Sounder) Processing Package (IMAPP), developed at the Space Science and Engineering Center, University of Wisconsin-Madison (SSEC/UW-Madison). IMAPP is a NASA-funded and freely-distributed software package which allows any ground station capable of receiving direct broadcast from Terra or Aqua to produce calibrated and geolocated radiances, and a suite of environmental products, of which the IDEA-I 48-hour forward trajectory prediction of high aerosol events is now a part. IDEA-I provides a tool for linking ground-based and satellite capabilities to support international air quality forecasting activities and is to be demonstrated internationally through user training and impact evaluation via a series of IMAPP workshops. This presentation describes the IMAPP implementation of IDEA-I in terms of its simple installation and configuration, and through examples of its operation in several regions known for periodic high aerosol events.; Screen capture of the University of Wisconsin implementation of the real-time direct broadcast IDEA-I Air Quality monitoring

  14. Characteristics of a Direct Current-driven plasma jet operated in open air

    NASA Astrophysics Data System (ADS)

    Li, Xuechen; Di, Cong; Jia, Pengying; Bao, Wenting

    2013-09-01

    A DC-driven plasma jet has been developed to generate a diffuse plasma plume by blowing argon into the ambient air. The plasma plume, showing a cup shape with a diameter of several centimeters at a higher voltage, is a pulsed discharge despite a DC voltage is applied. The pulse frequency is investigated as a function of the voltage under different gap widths and gas flow rates. Results show that plasma bullets propagate from the hollow needle to the plate electrode by spatially resolved measurement. A supposition about non-electroneutral trail of the streamer is proposed to interpret these experimental phenomena.

  15. Combustion and NOx emission characteristics with respect to staged-air damper opening in a 600 MWe down-fired pulverized-coal furnace under deep-air-staging conditions.

    PubMed

    Kuang, Min; Li, Zhengqi; Wang, Zhihua; Jing, Xinjing; Liu, Chunlong; Zhu, Qunyi; Ling, Zhongqian

    2014-01-01

    Deep-air-staging combustion conditions, widely used in tangential-fired and wall-arranged furnaces to significantly reduce NOx emissions, are premature up to now in down-fired furnaces that are designed especially for industry firing low-volatile coals such as anthracite and lean coal. To uncover combustion and NOx emission characteristics under deep-air-staging conditions within a newly operated 600 MWe down-fired furnace and simultaneously understand the staged-air effect on the furnace performance, full-load industrial-size measurements taken of gas temperatures and species concentrations in the furnace, CO and NOx emissions in flue gas, and carbon in fly ash were performed at various staged-air damper openings of 10%, 20%, 30%, and 50%. Increasing the staged-air damper opening, gas temperatures along the flame travel (before the flame penetrating the staged-air zone) increased initially but then decreased, while those in the staged-air zone and the upper part of the hopper continuously decreased and increased, respectively. On opening the staged-air damper to further deepen the air-staging conditions, O2 content initially decreased but then increased in both two near-wall regions affected by secondary air and staged air, respectively, whereas CO content in both two regions initially increased but then decreased. In contrast to the conventional understanding about the effects of deep-air-staging conditions, here increasing the staged-air damper opening to deepen the air-staging conditions essentially decreased the exhaust gas temperature and carbon in fly ash and simultaneously increased both NOx emissions and boiler efficiency. In light of apparently low NOx emissions and high carbon in fly ash (i.e., 696-878 mg/m(3) at 6% O2 and 9.81-13.05%, respectively) developing in the down-fired furnace under the present deep-air-staging conditions, further adjustments such as enlarging the staged-air declination angle to prolong pulverized-coal residence times in the

  16. A sensor management architecture concept for monitoring emissions from open-air demil operations.

    SciTech Connect

    Johnson, Michael M.; Robinson, Jerry D.; Stoddard, Mary Clare; Horn, Brent A.; Lipkin, Joel; Foltz, Greg W.

    2005-09-01

    Sandia National Laboratories, CA proposed a sensor concept to detect emissions from open-burning/open-detonation (OB/OD) events. The system would serve two purposes: (1) Provide data to demilitarization operations about process efficiency, allowing process optimization for cleaner emissions and higher efficiency. (2) Provide data to regulators and neighboring communities about materials dispersing into the environment by OB/OD operations. The proposed sensor system uses instrument control hardware and data visualization software developed at Sandia National Laboratories to link together an array of sensors to monitor emissions from OB/OD events. The suite of sensors would consist of various physical and chemical detectors mounted on stationary or mobile platforms. The individual sensors would be wirelessly linked to one another and controlled through a central command center. Real-time data collection from the sensors, combined with integrated visualization of the data at the command center, would allow for feedback to the sensors to alter operational conditions to adjust for changing needs (i.e., moving plume position, increased spatial resolution, increased sensitivity). This report presents a systems study of the problem of implementing a sensor system for monitoring OB/OD emissions. The goal of this study was to gain a fuller understanding of the political, economic, and technical issues for developing and fielding this technology.

  17. Afterburner performance of film-vaporizing V-gutters for inlet temperatures up to 1255 K

    NASA Technical Reports Server (NTRS)

    Branstetter, J. R.; Reck, G. M.

    1973-01-01

    Combustion tests of five variations of an integral, spray-bar - flameholder combination were conducted in a 0.49-m-diameter duct. Emphasis was on low levels of augmentation. Fuel impinged on guide plates, mixed with a controlled amount of inlet air, vaporized, and was guided into the V-gutter wake. Combustor length was 0.92 m. Good performance was demonstrated at fuel-air ratios less than 0.025 for inlet temperatures of 920 to 1255 K. Maximum combustion efficiency occured in the vicinity of fuel-air ratios of 0.02 and was 92 to 100 percent, depending on the inlet temperature. Lean blowout fuel-air ratios were in the vicinity of 0.005. Improvements in rich-limit blowout resulted from enlarging the guide-flow passageway areas. Other means of extending the operating range are suggested. A simplified afterburner concept for application to advanced engines is described.

  18. Bottom up approach to estimate air pollution of rice residue open burning in Thailand

    NASA Astrophysics Data System (ADS)

    Cheewaphongphan, Penwadee; Garivait, Savitri

    2013-02-01

    Rice residue open burning is a farmer activity potentially contributes to global warming. This study was conducted with the objective of examining the spatial and temporal distribution of emissions from rice residue open burning in Thailand by using questionnaire survey and field experimentation. A sample of 1000 Thai farmers was interviewed in order to study the fire behaviours of farmers. One hundred and twenty rice sampling plots were selected for measuring rice residue characteristics. Of the farmer's fire behaviour, 45% of farmer regularly uses prescribed burning technique for land preparation activities. The amount of rice residue was approximately 117.7 Mt. Although nearly 60% of total residue was subjected to burning in the fields, only 15% of rice residue is actually burned in the fields because the residue and soil have high moisture content. The burning emissions are computed at 1.67 Mt of CO, 0.04 Mt of NOx, 0.35 Mt of PM2.5, 0.12 Mt of PM10, and 0.01 Mt of BC. Approximately 30%, 26%, and 17% of all emissions are contributed by the lower-northern, central, and western regions of Thailand, respectively. Moreover, 31% and 30% of all emissions are annually emitted from December to January and April to May over one month periods following each harvesting season. The comparisons of rice residue burning emissions provided by this study and previous studies have found the emissions discovered in this study to range from one to five times higher than the finding of previous studies. This finding demonstrates the importance of the assessment of activity data specific to farming fire characteristics.

  19. Time and space in the middle paleolithic: Spatial structure and occupation dynamics of seven open-air sites.

    PubMed

    Clark, Amy E

    2016-05-06

    The spatial structure of archeological sites can help reconstruct the settlement dynamics of hunter-gatherers by providing information on the number and length of occupations. This study seeks to access this information through a comparison of seven sites. These sites are open-air and were all excavated over large spatial areas, up to 2,000 m(2) , and are therefore ideal for spatial analysis, which was done using two complementary methods, lithic refitting and density zones. Both methods were assessed statistically using confidence intervals. The statistically significant results from each site were then compiled to evaluate trends that occur across the seven sites. These results were used to assess the "spatial consistency" of each assemblage and, through that, the number and duration of occupations. This study demonstrates that spatial analysis can be a powerful tool in research on occupation dynamics and can help disentangle the many occupations that often make up an archeological assemblage.

  20. Perspective: Maintaining surface-phase purity is key to efficient open air fabricated cuprous oxide solar cells

    SciTech Connect

    Hoye, Robert L. Z. E-mail: jld35@cam.ac.uk; Ievskaya, Yulia; MacManus-Driscoll, Judith L. E-mail: jld35@cam.ac.uk; Brandt, Riley E.; Buonassisi, Tonio; Heffernan, Shane; Musselman, Kevin P.

    2015-02-01

    Electrochemically deposited Cu{sub 2}O solar cells are receiving growing attention owing to a recent doubling in efficiency. This was enabled by the controlled chemical environment used in depositing doped ZnO layers by atomic layer deposition, which is not well suited to large-scale industrial production. While open air fabrication with atmospheric pressure spatial atomic layer deposition overcomes this limitation, we find that this approach is limited by an inability to remove the detrimental CuO layer that forms on the Cu{sub 2}O surface. Herein, we propose strategies for achieving efficiencies in atmospherically processed cells that are equivalent to the high values achieved in vacuum processed cells.

  1. A new species of open-air processional column termite, Hospitalitermes nigriantennalis sp. n. (Termitidae), from Borneo

    PubMed Central

    Syaukani, Syaukani; Thompson, Graham J.; Zettel, Herbert; Pribadi, Teguh

    2016-01-01

    Abstract A new species of open-air processional column termite is here described based on the soldier and worker castes from eight colonies in north Barito, central Kalimantan. Hospitalitermes nigriantennalis sp. n. is readily distinguished in the field from related Hospitalitermes spp. by the light brown to orangish coloration of the soldier head capsule that, further, is with vertex yellowish and nasus brownish. The soldier antenna and the maxillary and labial palps are blackish. By contrast, soldiers from other species of Hospitalitermes from this region have a uniformly black head capsule and antennae. Finally, Hospitalitermes nigriantennalis sp. n. has a minute indentation in the middle of the posterior part of head capsule, which further helps to differentiate this new species from other Hospitalitermes from the Indo-Malayan and Austro-Malayan regions. PMID:26877678

  2. Method to estimate drag coefficient at the air/ice interface over drifting open pack ice from remotely sensed data

    NASA Technical Reports Server (NTRS)

    Feldman, U.

    1984-01-01

    A knowledge in near real time, of the surface drag coefficient for drifting pack ice is vital for predicting its motions. And since this is not routinely available from measurements it must be replaced by estimates. Hence, a method for estimating this variable, as well as the drag coefficient at the water/ice interface and the ice thickness, for drifting open pack ice was developed. These estimates were derived from three-day sequences of LANDSAT-1 MSS images and surface weather charts and from the observed minima and maxima of these variables. The method was tested with four data sets in the southeastern Beaufort sea. Acceptable results were obtained for three data sets. Routine application of the method depends on the availability of data from an all-weather air or spaceborne remote sensing system, producing images with high geometric fidelity and high resolution.

  3. Effects of inlet distortion on gas turbine combustion chamber exit temperature profiles

    NASA Astrophysics Data System (ADS)

    Maqsood, Omar Shahzada

    Damage to a nozzle guide vane or blade, caused by non-uniform temperature distributions at the combustion chamber exit, is deleterious to turbine performance and can lead to expensive and time consuming overhaul and repair. A test rig was designed and constructed for the Allison 250-C20B combustion chamber to investigate the effects of inlet air distortion on the combustion chamber's exit temperature fields. The rig made use of the engine's diffuser tubes, combustion case, combustion liner, and first stage nozzle guide vane shield. Rig operating conditions simulated engine cruise conditions, matching the quasi-non-dimensional Mach number, equivalence ratio and Sauter mean diameter. The combustion chamber was tested with an even distribution of inlet air and a 4% difference in airflow at either side. An even distribution of inlet air to the combustion chamber did not create a uniform temperature profile and varying the inlet distribution of air exacerbated the profile's non-uniformity. The design of the combustion liner promoted the formation of an oval-shaped toroidal vortex inside the chamber, creating localized hot and cool sections separated by 90° that appeared in the exhaust. Uneven inlet air distributions skewed the oval vortex, increasing the temperature of the hot section nearest the side with the most mass flow rate and decreasing the temperature of the hot section on the opposite side. Keywords: Allison 250, Combustion, Dual-Entry, Exit Temperature Profile, Gas Turbine, Pattern Factor, Reverse Flow.

  4. Aeroacoustic performance of a scoop inlet

    NASA Technical Reports Server (NTRS)

    Abbott, J. M.

    1977-01-01

    A low speed wind tunnel test demonstrated the aerodynamic and acoustic performance of a scoop inlet. Engine noise is directed upward by the extended lower lip of the scoop inlet. In addition, more of the scoop airflow comes in from above the inlet than below, leading to relatively higher surface velocities on the upper lip and lower surface velocities on the lower lip. These lower velocities on the lower lip result in a higher attainable angle of attack before internal flow separation occurs.

  5. Waves, Currents, & Bathymetric Evolution Near Inlets

    DTIC Science & Technology

    2013-09-30

    Jessup , A., R. Holman, C. Chickadel, S. Elgar; G. Farquharson, M . Haller, A. Kurapov, T. Özkan- Haller, B. Raubenheimer, J. Thomson, DARLA: Data...remotely sensed observations ( Jessup et al. 2012). Figure 1. Array of in situ wave and current sensors (white circles) deployed at New River...the inlet channel in depths from 1 to 10 m ]. (ii) Katama Inlet A numerical model for the water levels and flows in a two-inlet system was developed

  6. Axisymmetric inlet minimum weight design method

    NASA Technical Reports Server (NTRS)

    Nadell, Shari-Beth

    1995-01-01

    An analytical method for determining the minimum weight design of an axisymmetric supersonic inlet has been developed. The goal of this method development project was to improve the ability to predict the weight of high-speed inlets in conceptual and preliminary design. The initial model was developed using information that was available from inlet conceptual design tools (e.g., the inlet internal and external geometries and pressure distributions). Stiffened shell construction was assumed. Mass properties were computed by analyzing a parametric cubic curve representation of the inlet geometry. Design loads and stresses were developed at analysis stations along the length of the inlet. The equivalent minimum structural thicknesses for both shell and frame structures required to support the maximum loads produced by various load conditions were then determined. Preliminary results indicated that inlet hammershock pressures produced the critical design load condition for a significant portion of the inlet. By improving the accuracy of inlet weight predictions, the method will improve the fidelity of propulsion and vehicle design studies and increase the accuracy of weight versus cost studies.

  7. Radial inlet guide vanes for a combustor

    DOEpatents

    Zuo, Baifang; Simons, Derrick; York, William; Ziminsky, Willy S

    2013-02-12

    A combustor may include an interior flow path therethrough, a number of fuel nozzles in communication with the interior flow path, and an inlet guide vane system positioned about the interior flow path to create a swirled flow therein. The inlet guide vane system may include a number of windows positioned circumferentially around the fuel nozzles. The inlet guide vane system may also include a number of inlet guide vanes positioned circumferentially around the fuel nozzles and adjacent to the windows to create a swirled flow within the interior flow path.

  8. Planar Inlet Design and Analysis Process (PINDAP)

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Gruber, Christopher R.

    2005-01-01

    The Planar Inlet Design and Analysis Process (PINDAP) is a collection of software tools that allow the efficient aerodynamic design and analysis of planar (two-dimensional and axisymmetric) inlets. The aerodynamic analysis is performed using the Wind-US computational fluid dynamics (CFD) program. A major element in PINDAP is a Fortran 90 code named PINDAP that can establish the parametric design of the inlet and efficiently model the geometry and generate the grid for CFD analysis with design changes to those parameters. The use of PINDAP is demonstrated for subsonic, supersonic, and hypersonic inlets.

  9. Air-water fluxes of N₂O and CH₄ during microalgae (Staurosira sp.) cultivation in an open raceway pond.

    PubMed

    Ferrón, Sara; Ho, David T; Johnson, Zackary I; Huntley, Mark E

    2012-10-02

    The industrial-scale production of biofuels from cultivated microalgae has gained considerable interest in the last several decades. While the climate benefits of microalgae cultivation that result from the capture of atmospheric CO(2) are known, the counteracting effect from the potential emission of other greenhouse gases has not been well quantified. Here, we report the results of a study conducted at an industrial pilot facility in Hawaii to determine the air-water fluxes of N(2)O and CH(4) from open raceway ponds used to grow the marine diatom Staurosira sp. as a feedstock for biofuel. Dissolved O(2), CH(4), and N(2)O concentrations were measured over a 24 h cycle. During this time, four SF(6) tracer release experiments were conducted to quantify gas transfer velocities in the ponds, and these were then used to calculate air-water fluxes. Our results show that pond waters were consistently supersaturated with CH(4) (up to 725%) resulting in an average emission of 19.9 ± 5.6 μmol CH(4) m(-2) d(-1). Upon NO(3)(-) depletion, the pond shifted from being a source to being a sink of N(2)O, with an overall net uptake during the experimental period of 3.4 ± 3.5 μmol N(2)O m(-2) d(-1). The air-water fluxes of N(2)O and CH(4) expressed as CO(2) equivalents of global warming potential were 2 orders of magnitude smaller than the overall CO(2) uptake by the microalgae.

  10. Household air pollution following replacement of traditional open fire with an improved rocket type cookstove.

    PubMed

    Ochieng, Caroline; Vardoulakis, Sotiris; Tonne, Cathryn

    2017-02-15

    Cooking with biomass fuel is an important source of household air pollution (HAP) in developing countries, and a leading risk factor for ill-health. Although various designs of "improved cookstoves" (ICS) have been promoted as HAP interventions in these settings, few of them have undergone in-field evaluation, partly due to the challenge of conducting field measurements in remote settings. In this study we assessed the change in carbon monoxide (CO) exposure following the replacement of the traditional three-stone stove with a popular ICS in 49 homes in Western Kenya. We also assessed the suitability of using kitchen CO as a proxy for kitchen PM2.5. Reduction in 48h mean kitchen CO was 3.1ppm (95% CI: -8.1, 1.8) and in personal CO was 0.9ppm (95% CI: -4.3, 2.6) following stove replacements. Overall, 48-h kitchen and personal CO exposures were lower after stove replacement (28% and 12%, respectively) but with wide confidence intervals that also suggested possible increases in exposure. There were statistically significant reductions in peak kitchen and personal CO concentrations represented by the 8-h 95th percentile: reductions of 26.1ppm (95% CI: -44.6, -7.6) and 8.0ppm (95% CI: -12.2, -3.8), respectively. This is equivalent to 53% reduction in kitchen CO and 39% reduction in personal CO. We found good correlation between kitchen CO and PM2.5 concentrations overall (r=0.73, n=33 over averaging periods approximating 1day), which varied by time of day and exposure setting. These variations limit the applicability of CO as a proxy measure for PM2.5 concentrations. A combination of interventions, including better designed stoves, improved ventilation and cleaner fuels, may be needed to reduce HAP to levels that are likely to improve health.

  11. Experimental study on the inlet fogging system using two-fluid nozzles

    NASA Astrophysics Data System (ADS)

    Suryan, Abhilash; Kim, Dong Sun; Kim, Heuy Dong

    2010-04-01

    Large-capacity compressors in industrial plants and the compressors in gas turbine engines consume a considerable amount of power. The compression work is a strong function of the ambient air temperature. This increase in compression work presents a significant problem to utilities, generators and power producers when electric demands are high during the hot months. In many petrochemical process industries and gas turbine engines, the increase in compression work curtails plant output, demanding more electric power to drive the system. One way to counter this problem is to directly cool the inlet air. Inlet fogging is a popular means of cooling the inlet air to air compressors. In the present study, experiments have been performed to investigate the suitability of two-fluid nozzle for inlet fogging. Compressed air is used as the driving working gas for two-fluid nozzle and water at ambient conditions is dragged into the high-speed air jet, thus enabling the entrained water to be atomized in a very short distance from the exit of the two-fluid nozzle. The air supply pressure is varied between 2.0 and 5.0 bar and the water flow rate entrained is measured. The flow visualization and temperature and relative humidity measurements are carried out to specify the fogging characteristics of the two-fluid nozzle.

  12. Forward Operating Base Sharana: Poor Planning and Construction Resulted in $5.4 Million Spent for Inoperable Incinerators and Continued Use of Open-Air Burn Pits

    DTIC Science & Technology

    2013-12-01

    Forward Operating Base Sharana: Poor Planning and Construction Resulted in $5.4 Million Spent for Inoperable Incinerators and Continued Use of Open-Air...Burn Pits SIGAR 14-13-IP/Forward Operating Base Sharana Incinerators SIGAR DECEMBER 2 0 1 3 Report Documentation Page Form ApprovedOMB No. 0704... Incinerators and Continued Use of Open-Air Burn Pits 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  13. Microoxic Niches within the Thylakoid Stroma of Air-Grown Chlamydomonas reinhardtii Protect [FeFe]-Hydrogenase and Support Hydrogen Production under Fully Aerobic Environment1[OPEN

    PubMed Central

    Liran, Oded; Milrad, Yuval; Eilenberg, Haviva; Weiner, Iddo

    2016-01-01

    Photosynthetic hydrogen production in the microalga Chlamydomonas reinhardtii is catalyzed by two [FeFe]-hydrogenase isoforms, HydA1 and HydA2, both irreversibly inactivated upon a few seconds exposure to atmospheric oxygen. Until recently, it was thought that hydrogenase is not active in air-grown microalgal cells. In contrast, we show that the entire pool of cellular [FeFe]-hydrogenase remains active in air-grown cells due to efficient scavenging of oxygen. Using membrane inlet mass spectrometry, 18O2 isotope, and various inhibitors, we were able to dissect the various oxygen uptake mechanisms. We found that both chlororespiration, catalyzed by plastid terminal oxidase, and Mehler reactions, catalyzed by photosystem I and Flavodiiron proteins, significantly contribute to oxygen uptake rate. This rate is considerably enhanced with increasing light, thus forming local anaerobic niches at the proximity of the stromal face of the thylakoid membrane. Furthermore, we found that in transition to high light, the hydrogen production rate is significantly enhanced for a short duration (100 s), thus indicating that [FeFe]-hydrogenase functions as an immediate sink for surplus electrons in aerobic as well as in anaerobic environments. In summary, we show that an anaerobic locality in the chloroplast preserves [FeFe]-hydrogenase activity and supports continuous hydrogen production in air-grown microalgal cells. PMID:27443604

  14. Experimental, water droplet impingement data on two-dimensional airfoils, axisymmetric inlet and Boeing 737-300 engine inlet

    NASA Technical Reports Server (NTRS)

    Papadakis, M.; Elangovan, E.; Freund, G. A., Jr.; Breer, M. D.

    1987-01-01

    An experimental method has been developed to determine the droplet impingement characteristics on two- and three-dimensional bodies. The experimental results provide the essential droplet impingement data required to validate particle trajectory codes, used in aircraft icing analyses and engine inlet particle separator analyses. A body whose water droplet impingement characteristics are required is covered at strategic locations by thin strips of moisture absorbing (blotter) paper, and then exposed to an air stream containing a dyed-water spray cloud. Water droplet impingement data are extracted from the dyed blotter strips, by measuring the optical reflectance of the dye deposit on the strips, using an automated reflectometer. Impingement efficiency data obtained for a NACA 65(2)015 airfoil section, a supercritical airfoil section, and Being 737-300 and axisymmetric inlet models are presented in this paper.

  15. Internal Shock Interactions in Propulsion/Airframe Integrated Three-Dimensional Sidewall Compression Scramjet Inlets

    NASA Technical Reports Server (NTRS)

    Holland, Scott D.; Perkins, John N.

    1992-01-01

    The advantages and design requirements of propulsion/airframe integration for high Mach number flight have led to extensive study of the three-dimensional sidewall compression scramjet inlet in recent years. Recent research publications have indicated testing over a broad range of Mach number (2 to 18) in a variety of test gases, such as air, helium, and tetrafluoromethane. Multiple experimental techniques have been employed to obtain detailed internal shock interaction data, performance data, and inlet starting limits. Computational fluid dynamics has been effectively used for preliminary parametric studies as well as in parallel with experiments to aid in the explanation of unusual or unexpected flow phenomena. Inlets of this genre afford a relatively simple, generic geometry while producing a highly complex, three-dimensional flow field dominated by shock/shock and shock/boundary layer interactions. While the importance of the viscous effects in high speed inlet interactions is recognized, the present work addresses in a parametric fashion the inviscid effects of leading edge sweep, sidewall compression, and inflow Mach number on the internal shock structure in terms of inlet compression and mass capture. In the process, the source of the of the Mach number invariance with leading edge sweep for a constant sidewall compression class of inlet is identified, and a previously undocumented spillage phenomenon in a constant effective wedge angle class of inlets is discussed.

  16. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  17. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  18. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  19. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  20. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  1. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  2. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  3. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  4. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  5. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  6. External-Compression Supersonic Inlet Design Code

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    2011-01-01

    A computer code named SUPIN has been developed to perform aerodynamic design and analysis of external-compression, supersonic inlets. The baseline set of inlets include axisymmetric pitot, two-dimensional single-duct, axisymmetric outward-turning, and two-dimensional bifurcated-duct inlets. The aerodynamic methods are based on low-fidelity analytical and numerical procedures. The geometric methods are based on planar geometry elements. SUPIN has three modes of operation: 1) generate the inlet geometry from a explicit set of geometry information, 2) size and design the inlet geometry and analyze the aerodynamic performance, and 3) compute the aerodynamic performance of a specified inlet geometry. The aerodynamic performance quantities includes inlet flow rates, total pressure recovery, and drag. The geometry output from SUPIN includes inlet dimensions, cross-sectional areas, coordinates of planar profiles, and surface grids suitable for input to grid generators for analysis by computational fluid dynamics (CFD) methods. The input data file for SUPIN and the output file from SUPIN are text (ASCII) files. The surface grid files are output as formatted Plot3D or stereolithography (STL) files. SUPIN executes in batch mode and is available as a Microsoft Windows executable and Fortran95 source code with a makefile for Linux.

  7. Electrically heated particulate matter filter with recessed inlet end plugs

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2012-02-21

    A particulate matter (PM) filter includes filter walls having inlet ends and outlet ends. First adjacent pairs of the filter walls define inlet channels. Second adjacent pairs of the filter walls define outlet channels. Outlet end plugs are arranged in the inlet channels adjacent to the output ends. Inlet end plugs arranged in the outlet channels spaced from the inlet ends.

  8. Measurement of gas species, temperatures, coal burnout, and wall heat fluxes in a 200 MWe lignite-fired boiler with different overfire air damper openings

    SciTech Connect

    Jianping Jing; Zhengqi Li; Guangkui Liu; Zhichao Chen; Chunlong Liu

    2009-07-15

    Measurements were performed on a 200 MWe, wall-fired, lignite utility boiler. For different overfire air (OFA) damper openings, the gas temperature, gas species concentration, coal burnout, release rates of components (C, H, and N), furnace temperature, and heat flux and boiler efficiency were measured. Cold air experiments for a single burner were conducted in the laboratory. The double-swirl flow pulverized-coal burner has two ring recirculation zones starting in the secondary air region in the burner. As the secondary air flow increases, the axial velocity of air flow increases, the maxima of radial velocity, tangential velocity and turbulence intensity all increase, and the swirl intensity of air flow and the size of recirculation zones increase slightly. In the central region of the burner, as the OFA damper opening widens, the gas temperature and CO concentration increase, while the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and coal particles ignite earlier. In the secondary air region of the burner, the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and the gas temperature and CO concentration vary slightly. In the sidewall region, the gas temperature, O{sub 2} concentration, and NOx concentration decrease, while the CO concentration increases and the gas temperature varies slightly. The furnace temperature and heat flux in the main burning region decrease appreciably, but increase slightly in the burnout region. The NOx emission decreases from 1203.6 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 0% to 511.7 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 80% and the boiler efficiency decreases from 92.59 to 91.9%. 15 refs., 17 figs., 3 tabs.

  9. Measurement of Urban Air Quality by an Open-Path Quantum Cascade Laser Absorption Spectrometer in Beijing During Summer 2008

    NASA Astrophysics Data System (ADS)

    Michel, A. P.; Liu, P. Q.; Yeung, J. K.; Zhang, Y.; Baeck, M. L.; Pan, X.; Dong, H.; Wang, Z.; Smith, J. A.; Gmachl, C. F.

    2009-05-01

    The 2008 Olympic Games focused attention on the air quality of Beijing, China and served as an important test-bed for developing, deploying, and testing new technologies for analysis of air quality and regional climate in urban environments. Poor air quality in urban locations has a significant detrimental effect on the health of residents while also impacting both regional and global climate change. As a result, there exists a great need for highly sensitive trace gas sensors for studying the atmosphere of the urban environment. Open-path remote sensors are of particular interest as they can obtain data on spatial scales similar to those used in regional climate models. Quantum cascade lasers (QCLs) can be designed for operation in the mid-infrared (mid-IR) with a central wavelength anywhere between 3 to 24 μm and made tunable over a wavelength interval of over 0.1 μm. The Quantum Cascade Laser Open-Path System (QCLOPS) is a mid-infrared laser absorption spectrometer that uses a tunable, thermoelectrically cooled, pulsed Daylight Solutions Inc. QCL for measurement of trace gases. The system is aimed at applications with path lengths ranging from approximately 0.1 to 1.0 km. The system is designed to continuously monitor multiple trace gases [water vapor (H2O), ozone (O3), ammonia (NH3), and carbon dioxide (CO2)] in the lower atmosphere. A field campaign from July to September 2008 in Beijing used QCLOPS to study trace gas concentrations before, during, and after the Olympic Games in an effort to capture changes induced by emissions reduction methods. QCLOPS was deployed at the Institute of Atmospheric Physics - Chinese Academy of Sciences on the roof of a two-story building, at an approximate distance of 2 miles from the Olympic National Stadium ("The Bird's Nest.") QCLOPS operated with an open-path round trip distance of approximately 75 m. The system ran with minimal human interference, twenty-four hours per day for the full campaign period. In order to

  10. Analysis of Porous Media as Inlet Concept for Rotating Detonation Engines

    NASA Astrophysics Data System (ADS)

    Grogan, Kevin; Ihme, Matthias; Department of Mechanical Engineering Team

    2016-11-01

    Rotating detonation engines combust reactive gas mixtures with a high-speed, annularly-propagating detonation wave, which provides many advantages including a stagnation pressure gain and a compact, lightweight design. However, the optimal design of the inlet to the combustion chamber inlet is a moot topic since improper design can significantly reduce detonability and increase pressure losses. The highly diffusive properties of porous media could make it an ideal material to prevent the flashback of the detonation wave and therefore, allow the inlet gas to be premixed. Motivated by this potential, this work employs simulation to evaluate the application of porous media to the inlet of a rotating detonation engine as a novel means to stabilize a detonation wave while reducing the pressure losses incurred by non-ideal mixing strategies. Department of the Air Force.

  11. The Unsteady Response of an Axial Flow Turbo-Machinery Rotor to Inlet Flow Distortions.

    DTIC Science & Technology

    1978-10-12

    the rotor inflow velocity. Distorted inlet flow is a very realistic and prevalent problem in jet air - craft engines, and the consequences of...Turbomachinery In designing the blading of a compressor or turbine, the air flow is assumed to be steady. The existence of a uniform, steady flow is...surface of the air - k- foil. When this occurs in a compressor, surge can occur. Surge will result in very large fluctuating forces on the blades which

  12. Biochemical acclimation, stomatal limitation and precipitation patterns underlie decreases in photosynthetic stimulation of Soybean (Glycine max) at elevated [CO2] and temperatures under fully open air field conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The net effect of elevated [CO2] and temperature on photosynthetic acclimation and plant productivity is poorly resolved. We assessed the effects of canopy warming and fully open air [CO2] enrichment on 1) the acclimation of two biochemical parameters that frequently limit photosynthesis (A), the ma...

  13. 30 CFR 75.507-1 - Electric equipment other than power-connection points; outby the last open crosscut; return air...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment other than power-connection points; outby the last open crosscut; return air; permissibility requirements. 75.507-1 Section 75.507-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY...

  14. AUTOMATED DECONVOLUTION OF COMPOSITE MASS SPECTRA OBTAINED WITH AN OPEN-AIR IONIZATIONS SOURCE BASED ON EXACT MASSES AND RELATIVE ISOTIPIC ABUNDANCES

    EPA Science Inventory

    Chemicals dispersed by accidental, deliberate, or weather-related events must be rapidly identified to assess health risks. Mass spectra from high levels of analytes obtained using rapid, open-air ionization by a Direct Analysis in Real Time (DART®) ion source often contain

  15. PCDD/Fs in air and soil around an e-waste dismantling area with open burning of insulated wires in south China.

    PubMed

    Ren, M; Tang, Y H; Peng, P A; Cai, Y

    2015-05-01

    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in ambient air and farmland soil sampled in 2006 around an e-waste dismantling area with open burning of insulated wires in Longtang in south China were investigated. The total toxic equivalent concentrations of PCDD/Fs were 3.2-31.7 pg/m(3) in air and 5.8 12.4 ng/kg in farmland soil at an e-waste site and 0.063-0.091 pg/m(3) in air at a background site. PCDD/Fs in the air at the e-waste site were characterized with dominant 1,2,3,4,6,7,8-HpCDF and OCDF and higher concentrations of furans than dioxins, suggesting open burning of insulated wires was likely to be the main source of PCDD/Fs. Compared with the results in this study, the level of PCDD/F tended to lessen with the average TEQ concentration decreasing by 41 % and the pattern changed to be dominated by OCDD in the air of Longtang in 2010 when insulated wires were openly burned in only a small scale. Our results indicate that the lower chlorinated congeners with higher vapor pressures have enhanced atmospheric transport tendencies.

  16. The effect of high dose on residual radicals in open air irradiated α-T UHMWPE resin powder

    NASA Astrophysics Data System (ADS)

    Mehmood, Malik S.; Shah, Jahan M.; Mishra, Sanjay R.; Walters, Benjamin M.

    2013-03-01

    Powder samples of UHMWPE (GUR 1020) containing 0.1 wt%. vitamin E (α-tocopherol, α-T) were irradiated at room temperature in air for doses of 30-kGy, 65-kGy or 100-kGy (60Co). After irradiation, they were stored at -78.5 °C (dry ice temperature) for 1 year and then opened to air at room temperature. Following the decay of the primary alkyl and allyl radicals (at room temperature in air), growth of the carbon-centered polyenyl R1 (-˙CH-[-CHCH-]m-, m≥3), and the oxygen-centered di- or tri-enyl R2 (-˙OCH-[-CHCH-]m-, m≤3) residual radicals were measured for 8 weeks. An X-band electron spin resonance (ESR) spectrometer was used for radical measurements. The initial relative radical concentrations (R2/R1) were found to be 10.13, 4.6 and 3.7 for the 65-kGy, 30-kGy and 100-kGy samples, respectively. R1 and R2 were both found to grow significantly in the 65-kGy sample while they grew only slightly in the 30-kGy and 100-kGy samples. In 65-kGy sample, R1 grew faster than R2 and the relative concentration R2/R1 was reduced from 10.13 to 2.9 for the 65-kGy sample while those for the 30-kGy and 100-kGy samples reduced only slightly, from 4.6 to 3.5 and 3.7 to 3.2, respectively. The behavior of the residual radicals can be explained by Raman spectroscopic data which suggest that the 65-kGy samples had a higher percentage of amorphous regions when compared to the 30-kGy or 100-kGy ones (21.7 compared to 15.7 or 17.9) and also suggest a lower percentage of interfacial regions (16.4 compared to 25.6 or 17.5) and a lower level of structural disorder (0.26 compared to 0.44 or 0.27).

  17. Plasma control of shock wave configuration in off-design mode of M = 2 inlet

    NASA Astrophysics Data System (ADS)

    Falempin, Francois; Firsov, Alexander A.; Yarantsev, Dmitry A.; Goldfeld, Marat A.; Timofeev, Konstantin; Leonov, Sergey B.

    2015-03-01

    The objective of this work was to study the steering effect of a weakly ionized plasma on a supersonic flow structure in a two-dimensional aerodynamic configuration with a three-shock compression ramp in an off-design operational mode. Experiments were performed in wind tunnel T-313 of ITAM SB RAS, with the model air inlet designed for operation at a flow of Mach number M = 2. The inlet was tested at M = 2, 2.5, and 3 and with Re = (25-36) × 106/m and an angle of attack AoA = 0°, 5°, and 8°. For the regulation of the inlet characteristics, a plasma generator with electrical power W pl = 2-10 kW was flush-mounted upstream of the compression ramp. A significant plasma effect on the shock configuration at the inlet and on the flow parameters after air compression is considered. It is shown that the main shock wave angle is controllable by means of the plasma power magnitude and, therefore, can be accurately adjusted to the cowl lip of an inlet with a fixed geometry. An additional plasma effect has been demonstrated through a notable increase in the pressure recovery coefficient in a flowpass extension behind the inlet because of an nearly isentropic pattern of flow compression with the plasma turned on. Numerical simulation brings out the details of 3D distribution of the flow structure and parameters throughout the model at thermal energy deposition in inlet near the compression surfaces. We conclude that the plasma-based technique may be a feasible method for expanding supersonic inlet operational limits.

  18. Landscapes, depositional environments and human occupation at Middle Paleolithic open-air sites in the southern Levant, with new insights from Nesher Ramla, Israel

    NASA Astrophysics Data System (ADS)

    Zaidner, Yossi; Frumkin, Amos; Friesem, David; Tsatskin, Alexander; Shahack-Gross, Ruth

    2016-04-01

    Middle Paleolithic human occupation in the Levant (250-50 ka ago) has been recorded in roofed (cave and rockshelter) and open-air sites. Research at these different types of sites yielded different perspectives on the Middle Paleolithic human behavior and evolution. Until recently, open-air Middle Paleolithic sites in the Levant were found in three major sedimentary environments: fluvial, lake-margin and spring. Here we describe a unique depositional environment and formation processes at the recently discovered open-air site of Nesher Ramla (Israel) and discuss their contribution to understanding site formation processes in open-air sites in the Levant. The site is 8-m-thick Middle Paleolithic sequence (OSL dated to 170-80 ka) that is located in a karst sinkhole formed by gravitational deformation and sagging into underground voids. The sedimentary sequence was shaped by gravitational collapse, cyclic colluviation of soil and gravel into the depression, waterlogging, in situ pedogenesis and human occupation. Original bedding and combustion features are well-preserved in the Lower archaeological sequence, a rare occurrence in comparison to other open-air archaeological sites. This phenomenon coincides with episodes of fast sedimentation/burial, which also allowed better preservation of microscopic remains such as ash. The Upper archaeological sequence does not exhibit bedding or preservation of ash, despite presence of heat-affected lithic artifacts, which makes it similar to other open-air sites in the Levant. We suggest that rate of burial is the major factor that caused the difference between the Upper and Lower sequences. The differences in the burial rate may be connected to environmental and vegetation changes at the end of MIS 6. We also identified an interplay between sediment in-wash and density of human activity remains, i.e. during episodes of low natural sediment input the density of artifacts is higher relative to episodes with high rate of sediment in

  19. Shock Positioning Controls Designs for a Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Kopasakis, George; Connolly, Joseph W.

    2010-01-01

    Under the NASA Fundamental Aeronautics Program, the Supersonics Project is working to overcome the obstacles to supersonic commercial flight. The supersonic inlet design that is utilized to efficiently compress the incoming air and deliver it to the engine has many design challenges. Among those challenges is the shock positioning of internal compression inlets, which requires active control in order to maintain performance and to prevent inlet unstarts due to upstream (freestream) and downstream (engine) disturbances. In this paper a novel feedback control technique is presented, which emphasizes disturbance attenuation among other control performance criteria, while it ties the speed of the actuation system(s) to the design of the controller. In this design, the desired performance specifications for the overall control system are used to design the closed loop gain of the feedback controller and then, knowing the transfer function of the plant, the controller is calculated to achieve this performance. The innovation is that this design procedure is methodical and allows maximization of the performance of the designed control system with respect to actuator rates, while the stability of the calculated controller is guaranteed.

  20. Research on Supersonic Inlet Bleed

    NASA Technical Reports Server (NTRS)

    Davis, David O.; Vyas, Manan A.; Slater, John W.

    2012-01-01

    Phase I data results of the Fundamental Inlet Bleed Experiments project at NASA Glenn Research Center (GRC) are presented which include flow coefficient results for two single-hole boundary-layer bleed configurations. The bleed configurations tested are round holes at inclination angles of 90deg and 20deg both having length-to-diameter ratios of 2.0. Results were obtained at freestream Mach numbers of 1.33, 1.62, 1.98, 2.46, and 2.92 and unit Reynolds numbers of 0.984, 1.89, and 2.46 10(exp 7)/m. Approach boundary-layer data are presented for each flow condition and the flow coefficient results are compared to existing multi-hole data obtained under similar conditions. For the 90deg hole, the single and multi-hole distributions agree fairly well with the exception that under supercritical operation, the multi-hole data chokes at higher flow coefficient levels. This behavior is also observed for the 20deg hole but to a lesser extent. The 20deg hole also shows a markedly different characteristic at subcritical operation. Also presented are preliminary results of a Computational Fluid Dynamics (CFD) analysis of both configurations at the Mach 1.33 and a unit Reynolds number of 2.46 10(exp 7)/m. Comparison of the results shows the agreement to be very good.

  1. Functionalization of Hydrogen-free Diamond-like Carbon Films using Open-air Dielectric Barrier Discharge Atmospheric Plasma Treatments

    SciTech Connect

    Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Instituto de Materiales de Madrid, C.S.I.C., Cantoblanco, 28049 Madrid, Spain; Instituto de Quimica-Fisica"Rocasolano"C.S.I.C., 28006 Madrid, Spain; Mahasarakham University, Mahasarakham 44150, Thailand; CASTI, CNR-INFM Regional Laboratory, L'Aquila 67100, Italy; SUNY Upstate Medical University, Syracuse, NY 13210, USA; Endrino, Jose; Endrino, J. L.; Marco, J. F.; Poolcharuansin, P.; Phani, A.R.; Allen, M.; Albella, J. M.; Anders, A.

    2007-12-28

    A dielectric barrier discharge (DBD) technique has been employed to produce uniform atmospheric plasmas of He and N2 gas mixtures in open air in order to functionalize the surface of filtered-arc deposited hydrogen-free diamond-like carbon (DLC) films. XPS measurements were carried out on both untreated and He/N2 DBD plasma treated DLC surfaces. Chemical states of the C 1s and N 1s peaks were collected and used to characterize the surface bonds. Contact angle measurements were also used to record the short- and long-term variations in wettability of treated and untreated DLC. In addition, cell viability tests were performed to determine the influence of various He/N2 atmospheric plasma treatments on the attachment of osteoblast MC3T3 cells. Current evidence shows the feasibility of atmospheric plasmas in producing long-lasting variations in the surface bonding and surface energy of hydrogen-free DLC and consequently the potential for this technique in the functionalization of DLC coated devices.

  2. Analysis of different materials subjected to open-air explosions in search of explosive traces by Raman microscopy.

    PubMed

    Zapata, Félix; García-Ruiz, Carmen

    2017-03-16

    Post-explosion scenes offer such chaos and destruction that evidence recovery and detection of post-blast residues from the explosive in the surrounding materials is highly challenging and difficult. The suitability of materials to retain explosives residues and their subsequent analysis has been scarcely investigated. Particularly, the use of explosive mixtures containing inorganic oxidizing salts to make improvised explosive devices (IEDs) is a current security concern due to their wide availability and lax control. In this work, a wide variety of materials such as glass, steel, plywood, plastic bag, brick, cardboard or cotton subjected to open-air explosions were examined using confocal Raman microscopy, aiming to detect the inorganic oxidizing salts contained in explosives as black powder, chloratite, dynamite, ammonium nitrate fuel oil and ammonal. Post-blast residues were detected through microscopic examination of materials surfaces. In general, the more homogeneous and smoother the surface was, the less difficulties and better results in terms of identification were obtained. However, those highly irregular surfaces were the most unsuitable collectors for the posterior identification of explosive traces by Raman microscopy. The findings, difficulties and some recommendations related to the identification of post-blast particles in the different materials studied are thoroughly discussed.

  3. Acute O 3 damage on first year coppice sprouts of aspen and maple sprouts in an open-air experiment.

    PubMed

    Darbah, Joseph N T; Jones, Wendy S; Burton, Andrew J; Nagy, John; Kubiske, Mark E

    2011-09-01

    We studied the effect of high ozone (O(3)) concentration (110-490 nmol mol(-1)) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O(3) pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O(3) exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O(3) and/or CO(2) for 12 years, were harvested. Acute O(3) damage was not uniform within the crowns of aspen suckers; it was most severe in the mature, fully expanded photosynthesizing leaves. Young expanding leaves showed no visible signs of acute O(3) damage contrary to expectations. Stomatal conductance played a primary role in the severity of acute O(3) damage as it directly controlled O(3) uptake. Maple sprouts, which had lower stomatal conductance, smaller stomatal aperture, higher stomatal density and larger leaf surface area, were tolerant of acute O(3) exposure. Moreover, elevated CO(2) did not ameliorate the adverse effects of acute O(3) dose on aspen and maple sprouts, in contrast to its ability to counteract the effects of long-term chronic exposure to lower O(3) levels.

  4. Acute O3 damage on first year coppice sprouts of aspen and maple sprouts in an open-air experiment

    SciTech Connect

    Darbah, J.N.; Nagy, J.; Jones, W. S.; Burton, A. J.; Kubiske, M. E.

    2011-10-01

    We studied the effect of high ozone (O{sub 3}) concentration (110-490 nmol mol{sup -1}) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O{sub 3} pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O{sub 3} exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O{sub 3} and/or CO{sub 2} for 12 years, were harvested. Acute O{sub 3} damage was not uniform within the crowns of aspen suckers; it was most severe in the mature, fully expanded photosynthesizing leaves. Young expanding leaves showed no visible signs of acute O{sub 3} damage contrary to expectations. Stomatal conductance played a primary role in the severity of acute O{sub 3} damage as it directly controlled O{sub 3} uptake. Maple sprouts, which had lower stomatal conductance, smaller stomatal aperture, higher stomatal density and larger leaf surface area, were tolerant of acute O{sub 3} exposure. Moreover, elevated CO{sub 2} did not ameliorate the adverse effects of acute O{sub 3} dose on aspen and maple sprouts, in contrast to its ability to counteract the effects of long-term chronic exposure to lower O{sub 3} levels.

  5. Engineering Schottky Contacts in Open-Air Fabricated Heterojunction Solar Cells to Enable High Performance and Ohmic Charge Transport

    PubMed Central

    2014-01-01

    The efficiencies of open-air processed Cu2O/Zn1–xMgxO heterojunction solar cells are doubled by reducing the effect of the Schottky barrier between Zn1–xMgxO and the indium tin oxide (ITO) top contact. By depositing Zn1–xMgxO with a long band-tail, charge flows through the Zn1–xMgxO/ITO Schottky barrier without rectification by hopping between the sub-bandgap states. High current densities are obtained by controlling the Zn1–xMgxO thickness to ensure that the Schottky barrier is spatially removed from the p–n junction, allowing the full built-in potential to form, in addition to taking advantage of the increased electrical conductivity of the Zn1–xMgxO films with increasing thickness. This work therefore shows that the Zn1–xMgxO window layer sub-bandgap state density and thickness are critical parameters that can be engineered to minimize the effect of Schottky barriers on device performance. More generally, these findings show how to improve the performance of other photovoltaic system reliant on transparent top contacts, e.g., CZTS and CIGS. PMID:25418326

  6. Highly efficient photocatalytic TiO2 coatings deposited by open air atmospheric pressure plasma jet with aerosolized TTIP precursor

    NASA Astrophysics Data System (ADS)

    Fakhouri, H.; Ben Salem, D.; Carton, O.; Pulpytel, J.; Arefi-Khonsari, F.

    2014-07-01

    A simple method to deposit photocatalytic TiO2 coatings, at a high rate (20-40 µm s-1), and with a high porosity, is reported in this paper. This method, which allows the treatment of membranes (with an 800 nm pore size), is based on the introduction of a liquid precursor sprayed into an open-air atmospheric pressure plasma jet (APPJ). The photocatalytic activity of the TiO2 thin films prepared by APPJ have been compared with our best N-doped TiO2 thin films, deposited by reactive radio frequency (RF) magnetron sputtering, previously reported in the literature. The morphology, chemical composition, photoelectrochemical, and photocatalytic properties of the coatings have been studied in this paper. Significant control of the porosity and crystallinity was achieved by varying the deposition parameters and the annealing temperature. Under optimized conditions, the TiO2 coatings deposited by APPJ are characterized by a higher photocatalytic activity as compared to the optimized thin films deposited by RF sputtering. This difference can be explained by the higher specific surface of the APPJ coatings. Finally, the most interesting characteristic of this APPJ-liquid spray process is its capacity to treat membranes without blocking the pores, and to produce photocatalytic membranes which can efficiently combine filtration and photocatalysis for water treatment.

  7. Limitations to soybean photosynthesis at elevated carbon dioxide in free-air enrichment and open top chamber systems.

    PubMed

    Bunce, James A

    2014-09-01

    It has been suggested that the stimulation of soybean photosynthesis by elevated CO2 was less in free-air carbon dioxide enrichment (FACE) systems than in open top chambers (OTC), which might explain smaller yield increases at elevated CO2 in FACE systems. However, this has not been tested using the same cultivars grown in the same location. I tested whether soybean photosynthesis at high light and elevated CO2 (ambient+180 μmol mol(-1)) was limited by electron transport (J) in FACE systems but by ribulose-bisphosphate carboxylation capacity (VCmax) in OTC. FACE systems with daytime and continuous CO2 enrichment were also compared. The results indicated that in both cultivars examined, midday photosynthesis at high light was always limited by VCmax, both in the FACE and in the OTC systems. Daytime only CO2 enrichment did not affect photosynthetic parameters or limitations, but did result in significantly smaller yields in both cultivars than continuous elevation. Photosynthesis measured at low photosynthetic photon flux density (PPFD) was not higher at elevated than at ambient CO2, because of an acclimation to elevated CO2 which was only evident at low measurement PPFDs.

  8. Ozone deposition to an oat crop ( Avena sativa L.) grown in open-top chambers and in the ambient air

    NASA Astrophysics Data System (ADS)

    Pleijel, H.; Wallin, G.; Karlsson, P. E.; Skarby, L.; Sellden, G.

    Fluxes and deposition velocities for ozone were determined for open-top chambers with and without an oat crop, and for the adjacent field, using a resistance analogue model and the aerodynamic wind-profile method, respectively. During a period when the canopy was green and the ambient wind speeds modest, the fluxes and deposition velocities were higher in the chamber with plants than in the field crop. The deposition to chamber walls and soil in the chamber only accounted for part of that difference. The deposition velocity for ozone to the crop was light-dependent both in the chamber with plants and in the ambient air. With increasing plant senescence, the deposition velocity declined and the light dependence disappeared. Fluctuations in deposition velocity superimposed on the overall declining trend followed the same temporal pattern in the chambers with and without plants. These fluctuations in deposition velocity may partly be explained by variations in surface wetness. Differences in boundary layer conductance between chamber and ambient, which under certain conditions may significantly influence the validity of the chamber as a test system, were observed.

  9. Le site acheuléen de plein air d'Holon (Israël) : premiers résultatsThe Acheulian open-air site from Holon (Israel): preliminary results

    NASA Astrophysics Data System (ADS)

    Chazan, Michael; Monchot, Hervé; Porat, Naomi; Lister, Adrian; Davies, Paul; Kolska Horwitz, Liora

    2001-02-01

    The open-air site of Holon (Israel), dated to an age of 200 000 years has yielded a large Acheulean bone and lithic assemblage. The association between the lithics and fauna clearly demonstrates that Hominids were the prime agents in creating the assemblage. The site of Holon plays a major role in understanding the Lower Palaeolithic of the Levantine coastal area.

  10. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2006-01-01

    This paper gives an overview of a research study conducted in support of the small-scale demonstration of an active flow control system for a boundary-layer-ingesting (BLI) inlet. The effectiveness of active flow control in reducing engine inlet circumferential distortion was assessed using a 2.5% scale model of a 35% boundary-layer-ingesting flush-mounted, offset, diffusing inlet. This experiment was conducted in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel at flight Mach numbers with a model inlet specifically designed for this type of testing. High mass flow actuators controlled the flow through distributed control jets providing the active flow control. A vortex generator point design configuration was also tested for comparison purposes and to provide a means to examine a hybrid vortex generator and control jets configuration. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow through the duct and the actuators. The distortion and pressure recovery were determined by 40 total pressure measurements on 8 rake arms each separated by 45 degrees and were located at the aerodynamic interface plane. The test matrix was limited to a maximum free-stream Mach number of 0.85 with scaled mass flows through the inlet for that condition. The data show that the flow control jets alone can reduce circumferential distortion (DPCP(sub avg)) from 0.055 to about 0.015 using about 2.5% of inlet mass flow. The vortex generators also reduced the circumferential distortion from 0.055 to 0.010 near the inlet mass flow design point. Lower inlet mass flow settings with the vortex generator configuration produced higher distortion levels that were reduced to acceptable levels using a hybrid vortex generator/control jets configuration that required less than 1% of the inlet mass flow.

  11. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2006-01-01

    This paper gives an overview of a research study conducted in support of the small-scale demonstration of an active flow control system for a boundary-layer-ingesting (BLI) inlet. The effectiveness of active flow control in reducing engine inlet circumferential distortion was assessed using a 2.5% scale model of a 35% boundary-layer-ingesting flush-mounted, offset, diffusing inlet. This experiment was conducted in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel at flight Mach numbers with a model inlet specifically designed for this type of testing. High mass flow actuators controlled the flow through distributed control jets providing the active flow control. A vortex generator point design configuration was also tested for comparison purposes and to provide a means to examine a hybrid vortex generator and control jets configuration. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow through the duct and the actuators. The distortion and pressure recovery were determined by 40 total pressure measurements on 8 rake arms each separated by 45 degrees and were located at the aerodynamic interface plane. The test matrix was limited to a maximum free-stream Mach number of 0.85 with scaled mass flows through the inlet for that condition. The data show that the flow control jets alone can reduce circumferential distortion (DPCPavg) from 0.055 to about 0.015 using about 2.5% of inlet mass flow. The vortex generators also reduced the circumferential distortion from 0.055 to 0.010 near the inlet mass flow design point. Lower inlet mass flow settings with the vortex generator configuration produced higher distortion levels that were reduced to acceptable levels using a hybrid vortex generator/control jets configuration that required less than 1% of the inlet mass flow.

  12. Wind- and Tide-Driven Cross-Inlet Circulation at New River Inlet, NC

    NASA Astrophysics Data System (ADS)

    Wargula, A.; Raubenheimer, B.; Elgar, S.

    2014-12-01

    The importance of cross-channel wind forcing to inlet circulation is examined using observations of winds, waves, water levels, and currents collected in and near New River Inlet, NC during May 2012. Although the direct effect of local wind forcing may be neglected in the subtidal along-inlet momentum balance, which is dominated by the pressure gradient, wave radiation stress gradient, and bottom friction, cross-inlet winds may have a significant effect on along-inlet dynamics by driving cross-inlet flows (approximately 0.1 to 0.3 m/s), which can mix lateral and vertical gradients in momentum and water properties. New River Inlet is 1000 m wide at the mouth and tapers to 100 m wide about 1000 m away from the mouth after two sharp 90° bends. Five colocated pressure gages and current profilers were deployed from the shallow (2-3 m water depth) ebb shoal outside the mouth through the deep (5-10 m depth) inlet channel to 200 m beyond the first 90° bend. The inlet is well mixed, and along-inlet tidal currents ranged from +/- 1.5 m/s, offshore significant wave heights from 0.5 to 2.5 m, and wind speeds from 0 to 16 m/s. Time series of currents and winds were lowpass-filtered to examine subtidal wind effects. At the first 90° bend, both surface and bottom cross-inlet flows were correlated (r2 = 0.6) with cross-inlet wind velocity. On the shallow ebb shoal, the cross-inlet flows also were correlated with cross-inlet wind velocity (r2 = 0.6). Cross-inlet flows exhibited a two-layer response to the wind inside the inlet and a depth-uniform response outside the mouth. The observations will be used to examine the momentum balance governing temporal and spatial variations in cross-inlet wind effects on inlet circulation. Funding provided by the Office of Naval Research, the Assistant Secretary of Defense for Research and Engineering, and a National Defense Science and Engineering Graduate Fellowship.

  13. The Origin of Inlet Buzz in a Mach 1.7 Low Boom Inlet Design

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Weir, Lois

    2014-01-01

    Supersonic inlets with external compression, having a good level performance at the critical operating point, exhibit a marked instability of the flow in some subcritical operation below a critical value of the capture mass flow ratio. This takes the form of severe oscillations of the shock system, commonly known as "buzz". The underlying purpose of this study is to indicate how Detached Eddy Simulation (DES) analysis of supersonic inlets will alter how we envision unsteady inlet aerodynamics, particularly inlet buzz. Presented in this paper is a discussion regarding the physical explanation underlying inlet buzz as indicated by DES analysis. It is the normal shock wave boundary layer separation along the spike surface which reduces the capture mass flow that is the controlling mechanism which determines the onset of inlet buzz, and it is the aerodynamic characteristics of a choked nozzle that provide the feedback mechanism that sustains the buzz cycle by imposing a fixed mean corrected inlet weight flow. Comparisons between the DES analysis of the Lockheed Martin Corporation (LMCO) N+2 inlet and schlieren photographs taken during the test of the Gulfstream Large Scale Low Boom (LSLB) inlet in the NASA 8x6 ft. Supersonic Wind Tunnel (SWT) show a strong similarity both in turbulent flow field structure and shock wave formation during the buzz cycle. This demonstrates the value of DES analysis for the design and understanding of supersonic inlets.

  14. Gas Turbine Engine Inlet Wall Design

    NASA Technical Reports Server (NTRS)

    Florea, Razvan Virgil (Inventor); Matalanis, Claude G. (Inventor); Stucky, Mark B. (Inventor)

    2016-01-01

    A gas turbine engine has an inlet duct formed to have a shape with a first ellipse in one half and a second ellipse in a second half. The second half has an upstream most end which is smaller than the first ellipse. The inlet duct has a surface defining the second ellipse which curves away from the first ellipse, such that the second ellipse is larger at an intermediate location. The second ellipse is even larger at a downstream end of the inlet duct leading into a fan.

  15. Aeroacoustic performance of a scoop inlet

    NASA Technical Reports Server (NTRS)

    Abbott, J. M.

    1977-01-01

    Results of a low speed wind tunnel test program are presented which demonstrate the aerodynamic and acoustic performance of a scoop inlet. Engine noise that would normally propagate toward the ground is directed upward by the extended lower lip of the scoop inlet. In addition, more of the scoop airflow comes in from above the inlet than below, leading to relatively higher surface velocities on the upper lip and lower surface velocities on the lower lip. These lower velocities on the lower lip result in a higher attainable angle of attack before internal flow separation occurs.

  16. Boundary conditions for unsteady supersonic inlet analyses

    NASA Astrophysics Data System (ADS)

    Mayer, David W.; Paynter, Gerald C.

    1994-06-01

    New bleed and compressor face boundary conditions have been developed to improve the accuracy of unsteady supersonic inlet calculations. The new bleed boundary conditions relate changes in the bleed hole discharge coefficient to changes in the local flow conditions; the local bleed flow rate can more than double as a shock moves forward over a bleed band in response to inlet flow disturbances. The effects of inlet flow disturbances on the flow at the compressor face are represented more realistically with this new boundary condition than with traditional fixed static pressure or mass flow conditions.

  17. Assessing plant response to ambient ozone: growth of young apple trees in open-top chambers and corresponding ambient air plots.

    PubMed

    Manning, W J; Cooley, D R; Tuttle, A F; Frenkel, M A; Bergweiler, C J

    2004-12-01

    Open-top chambers (OTCs) and corresponding ambient air plots (AA) were used to assess the impact of ambient ozone on growth of newly planted apple trees at the Montague Field research center in Amherst, MA. Two-year-old apple trees (Malus domestica Borkh 'Rogers Red McIntosh') were planted in the ground in circular plots. Four of the plots were enclosed with OTCs where incoming air was charcoal-filtered (CF); four were enclosed with OTCs where incoming air was not charcoal-filtered (NF) and four were not enclosed, allowing access to ambient air conditions (AA). Conditions in both CF and NF OTCs resulted in increased tree growth and changed incidence of disease and arthropod pests, compared to trees in AA. As a result, we were not able to use the OTC method to assess the impact of ambient ozone on growth of young apple trees in Amherst, MA.

  18. Compression-ignition Engine Performance at Altitudes and at Various Air Pressures and Temperatures

    NASA Technical Reports Server (NTRS)

    Moore, Charles S; Collins, John H

    1937-01-01

    Engine test results are presented for simulated altitude conditions. A displaced-piston combustion chamber on a 5- by 7-inch single cylinder compression-ignition engine operating at 2,000 r.p.m. was used. Inlet air temperature equivalent to standard altitudes up to 14,000 feet were obtained. Comparison between performance at altitude of the unsupercharged compression-ignition engine compared favorably with the carburetor engine. Analysis of the results for which the inlet air temperature, inlet air pressure, and inlet and exhaust pressure were varied indicates that engine performance cannot be reliably corrected on the basis of inlet air density or weight of air charge. Engine power increases with inlet air pressure and decreases with inlet air temperatures very nearly as straight line relations over a wide range of air-fuel ratios. Correction factors are given.

  19. Effects of Inlet Icing on Performance of Axial-flow Turbojet Engine in Natural Icing Conditions

    NASA Technical Reports Server (NTRS)

    Acker, Loren W; Kleinknecht, Kenneth S

    1950-01-01

    A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

  20. Freiluftschulen: Eine Historisch-Padagogische Randerscheinung als Reflex Sozial-Historischer Modernisierungsprozesse? Das Beispiel Belgiens (Open-Air Schools: A Marginal Appearance in Pedagogical History as a Reflection of Socio-Historical Processes of Modernization? The Example of Belgium).

    ERIC Educational Resources Information Center

    Depaepe, Marc; Simon, Frank

    2003-01-01

    Discusses the history of open-air schools using an evaluation of Belgian schools. Expounds on the complex relationship between educational space and the educational act, and between traditional and progressive education. Demonstrates that open-air schools provided the same education as traditional schools and were not a real alternative for…

  1. Morphological Impacts of Sea Level Rise Driven Wetland Loss on Two Florida Inlets

    NASA Astrophysics Data System (ADS)

    Lovering, J. L.; Adams, P. N.; Kline, S. W.

    2012-12-01

    Shoreline response to sea level rise has been extensively studied, but relatively little work has examined potential changes to tidal inlet systems, of which there are more than 70 on the U. S. Atlantic coast. Sea level rise can influence the hydrodynamics of an inlet system by flooding adjacent low-lying regions and changing distribution of wetland vegetation in the back barrier basin. If sea level rise causes wetland vegetation loss, a basin's tidal prism can increase by: (1) conversion of previously vegetated marsh land to open water, and/or (2) tidal wave attenuation reduction in the basin, which increases efficiency of tidal exchange. In this study, we used a simple conceptual model paired with empirical relationships to investigate how two Florida inlets, Saint Augustine Inlet and Ponce de Leon Inlet, with contrasting wetland configurations, are expected to respond to wetland loss. While both inlets have similar areas of vegetated wetland, the distributions of vegetation throughout the basins differ. For both inlets, the model indicates that a loss in wetland area leads to an increase in tidal prism, cross-sectional area, and ebb shoal volume. At the Saint Augustine Inlet basin, the wetland vegetation is mostly fringing, creating a main basin channel with little tidal wave attenuation. The Ponce de Leon Inlet site has a more complex tidal channel network in the back basin, which is caused the presence of numerous marsh islands. The tortuous path that flood tidal water must travel during a tidal exchange causes higher spatial rates of tidal wave attenuation. Wetland loss at the Ponce de Leon Inlet site should increase the tidal prism of the system through both aforementioned mechanisms, whereas wetland loss at the Saint Augustine Inlet site should change the tidal prism only by increasing basin area. We conclude that tidal inlets with greater initial tidal wave attenuation have the potential to experience greater increases in tidal prism due to wetland loss

  2. Conditions for the use of infrared camera diagnostics in energy auditing of the objects exposed to open air space at isothermal sky

    NASA Astrophysics Data System (ADS)

    Kruczek, Tadeusz

    2015-03-01

    Convective and radiation heat transfer take place between various objects placed in open air space and their surroundings. These phenomena bring about heat losses from pipelines, building walls, roofs and other objects. One of the main tasks in energy auditing is the reduction of excessive heat losses. In the case of a low sky temperature, the radiation heat exchange is very intensive and the temperature of the top part of the horizontal pipelines or walls is lower than the temperature of their bottom parts. Quite often this temperature is also lower than the temperature of the surrounding atmospheric air. In the case of overhead heat pipelines placed in open air space, it is the ground and sky that constitute the surroundings. The aforementioned elements of surroundings usually have different values of temperature. Thus, these circumstances bring about difficulties during infrared inspections because only one ambient temperature which represents radiation of all surrounding elements must be known during the thermovision measurements. This work is aimed at the development of a method for determination of an equivalent ambient temperature representing the thermal radiation of the surrounding elements of the object under consideration placed in open air space, which could be applied at a fairly uniform temperature of the sky during the thermovision measurements as well as for the calculation of radiative heat losses.

  3. The Peel Inlet-Harvey Estuary Study.

    ERIC Educational Resources Information Center

    Walker, Warren; Black, Ronald

    1979-01-01

    Describes how the department of physics of the Western Australian Institute of Technology (WAIT) has been involved in the Peel Inlet-Harvey Estuary study. An appendix which presents the departmental approach to curriculum matters is also included. (HM)

  4. Computational analysis of ramjet engine inlet interaction

    NASA Technical Reports Server (NTRS)

    Duncan, Beverly; Thomas, Scott

    1992-01-01

    A computational analysis of a ramjet engine at Mach 3.5 has been conducted and compared to results obtained experimentally. This study focuses on the behavior of the inlet both with and without combustor backpressure. Increased backpressure results in separation of the body side boundary layer and a resultant static pressure rise in the inlet throat region. The computational results compare well with the experimental data for static pressure distribution through the engine, inlet throat flow profiles, and mass capture. The computational analysis slightly underpredicts the thickness of the engine body surface boundary layer and the extent of the interaction caused by backpressure; however, the interaction is observed at approximately the same level of backpressure both experimentally and computationally. This study demonstrates the ability of two different Navier-Stokes codes, namely RPLUS and PARC, to calculate the flow features of this ramjet engine and to provide more detailed information on the process of inlet interaction and unstart.

  5. Noise suppression with high Mach number inlets

    NASA Technical Reports Server (NTRS)

    Lumsdaine, E.; Cherng, J. G.; Tag, I.

    1976-01-01

    Experimental results were obtained for two types of high Mach number inlets, one with a translating centerbody and a fixed geometry inlet (collapsing cowl) with no centerbody. The aerodynamic and acoustic performance of these inlets was examined. The effects of area ratio, length/diameter ratio, and lip geometry were among several parameters investigated. The translating centerbody type inlet was found to be superior to the collapsing cowl both acoustically and aerodynamically, particularly for area ratios greater than 1.5. Comparison of length/diameter ratio and area ratio effects on performance near choked flow showed the latter to be more significant. Also, greater high frequency noise attenuation was achieved by increasing Mach number from low to high subsonic values.

  6. Sample inlet tube for ion source

    DOEpatents

    Prior, David [Hermiston, OR; Price, John [Richland, WA; Bruce, Jim [Oceanside, CA

    2002-09-24

    An improved inlet tube is positioned within an aperture through the device to allow the passage of ions from the ion source, through the improved inlet tube, and into the interior of the device. The inlet tube is designed with a larger end and a smaller end wherein the larger end has a larger interior diameter than the interior diameter of the smaller end. The inlet tube is positioned within the aperture such that the larger end is pointed towards the ion source, to receive ions therefrom, and the smaller end is directed towards the interior of the device, to deliver the ions thereto. Preferably, the ion source utilized in the operation of the present invention is a standard electrospray ionization source. Similarly, the present invention finds particular utility in conjunction with analytical devices such as mass spectrometers.

  7. Small inlet optical panel and a method of making a small inlet optical panel

    DOEpatents

    Veligdan, James T.; Slobodin, David

    2001-01-01

    An optical panel having a small inlet, and a method of making a small inlet optical panel, are disclosed, which optical panel includes a individually coating, stacking, and cutting a first plurality of stacked optical waveguides to form an outlet face body with an outlet face, individually coating, stacking, and cutting a second plurality of stacked optical waveguides to form an inlet face body with an inlet face, and connecting an optical coupling element to the first plurality and to the second plurality, wherein the optical coupling element redirects light along a parallel axis of the inlet face to a parallel axis of the outlet face. In the preferred embodiment of the present invention, the inlet face is disposed obliquely with and askew from the outlet face.

  8. Effect of inlet disturbances on fan inlet noise during a static test

    NASA Technical Reports Server (NTRS)

    Bekofske, K. L.; Sheer, R. E., Jr.; Wang, J. C. F.

    1977-01-01

    Measurements of fan rotor inlet noise taken during static test situations are at variance with aircraft engine flight data. In particular, static tests generally yield a significantly higher tone at blade passage frequency than that measured during flight. To explain this discrepancy, the extent of the influence of inlet ground vortices and large-scale inlet turbulence on the forward-radiated fan noise measured at a static test facility was investigated. While such inlet disturbances were generated intentionally in an anechoic test chamber, far-field acoustic measurements and inlet flow-field hot-film mappings of a fan rotor were obtained. Experimental results indicate that the acoustic effect of such disturbances appears to be less severe for supersonic than for subsonic tip speeds. Further, a reverse flow that occurs on the exterior cowl in static test facilities appears to be an additional prime candidate for creating inlet disturbances and causing variance between flight and static acoustic data.

  9. Inlet Processes at Eel Pond, Falmouth, Massachusetts.

    DTIC Science & Technology

    1984-10-01

    7 D -A147 548 INLET PROCESSES AT EEL POND FALMOUTH MRSS CHUSETi7 jV 1/2.COASTAL ENGINEERING RESEARCH CENTER YICKSBURG MS A E DEWRLL ET AL. OCT 84...42 c. Sediment Transport. ................... 42 d . Aerial Photograph: 21 November 1938. .......... 46 e. Aerial Photograph...Structural Changes to Inlet Hydraulics. ......... 59 c. Predicted Channel Stability .. .............. 69 d . Longshore Transport Estimates

  10. Circulation exchange patterns in Sinclair Inlet, Washington

    USGS Publications Warehouse

    Noble, Marlene A.; Rosenberger, Kurt J.; Paulson, Anthony J.; Gartner, Anne L.

    2013-01-01

    In 1994, the U.S. Geological Survey (USGS), in cooperation with the U.S. Navy, deployed three sets of moorings in Sinclair Inlet, which is a relatively small embayment on the western side of Puget Sound (fig. 1). This inlet is home to the Puget Sound Naval Shipyard. One purpose of the measurement program was to determine the transport pathways and fate of contaminants known to be present in Sinclair Inlet. Extensive descriptions of the program and the resultant information about contaminant pathways have been reported in Gartner and others (1998). This report primarily focused on the bottom boundary layer and the potential for resuspension and transport of sediments on the seabed in Sinclair Inlet as a result of tides and waves. Recently (2013), interest in transport pathways for suspended and dissolved materials in Sinclair Inlet has been rekindled. In particular, the USGS scientists in Washington and California have been asked to reexamine the datasets collected in the earlier study to refine not only our understanding of transport pathways through the inlet, but to determine how those transport pathways are affected by subtidal currents, local wind stress, and fresh water inputs. Because the prior study focused on the bottom boundary layer and not the water column, a reanalysis of the datasets could increase our understanding of the dynamic forces that drive transport within and through the inlet. However, the early datasets are limited in scope and a comprehensive understanding of these transport processes may require more extensive datasets or the development of a detailed numerical model of transport processes for the inlet, or both.

  11. Multiducted Inlet Combustor Research and Development.

    DTIC Science & Technology

    1982-10-01

    qualitative data from the multi-ducted inlet combustor configuration for flow analysis and matematical modeling purposes. The major portion of the support...data on multi-ducted inlet combustor configurations. These efforts will provide the information necessary to perform flow field analysis and aid in the...instrumentation, test program, data reduction, data presentation, flow field analysis and math modelling efforts, and conclusions and recommendations. SECTION 2

  12. Boundary conditions for unsteady supersonic inlet analyses

    NASA Astrophysics Data System (ADS)

    Mayer, David W.; Paynter, Gerald C.

    1994-06-01

    New bleed and compresor face boundary conditions have been developed to improve the accuracy of unsteady supersonic inlet calculations. The new bleed boundary condition relates changes in the bleed hole discharge coefficient to change the local flow conditions; the local bleed flow rate can more than double as a shock moves forward over a bleed band in response to inlet flow disturbances. The stability margin of the inlet is strongly dependent on the throat bleed configuration since the locally rapid increase in bleed flow has a stong effect on the motion of the normal shock. The new compressor face boundary condition accounts for changes in the unsteady flow conditions at the compressor face by specifying the compressor face corrected mass flow or Mach number either as a constant or as a linear function of the stagnation conditions. The effects of inlet flow disturbances on the flow at the compressor face are represented more realistically with this new boundary condition than with traditional fixed static pressure or mass flow conditions. Euler calculations of the dynamic response of an inlet flow to a flow disturbance at the compressor face with 20- and 90-deg throat bleed hole angles are reported. These results indicate that an extra margin of stability for the inlet is obtained with 90-deg bleed holes because the increase in bleed flow rate as the shock moves forward over a bleed is much larger for 90-deg holes than for 20-deg holes.

  13. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2008-01-01

    An experimental study was conducted to provide the first demonstration of an active flow control system for a flush-mounted inlet with significant boundary-layer-ingestion in transonic flow conditions. The effectiveness of the flow control in reducing the circumferential distortion at the engine fan-face location was assessed using a 2.5%-scale model of a boundary-layer-ingesting offset diffusing inlet. The inlet was flush mounted to the tunnel wall and ingested a large boundary layer with a boundary-layer-to-inlet height ratio of 35%. Different jet distribution patterns and jet mass flow rates were used in the inlet to control distortion. A vane configuration was also tested. Finally a hybrid vane/jet configuration was tested leveraging strengths of both types of devices. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow rates through the duct and the flow control actuators. The distortion and pressure recovery were measured at the aerodynamic interface plane. The data show that control jets and vanes reduce circumferential distortion to acceptable levels. The point-design vane configuration produced higher distortion levels at off-design settings. The hybrid vane/jet flow control configuration reduced the off-design distortion levels to acceptable ones and used less than 0.5% of the inlet mass flow to supply the jets.

  14. Admiralty Inlet Advanced Turbulence Measurements: May 2015

    DOE Data Explorer

    Kilcher, Levi

    2015-05-18

    This data is from measurements at Admiralty Head, in Admiralty Inlet (Puget Sound) in May of 2015. The measurements were made using Inertial Motion Unit (IMU) equipped ADVs mounted on a 'StableMoor' (Manufacturer: DeepWater Buoyancy) buoy and a Tidal Turbulence Mooring (TTM). These platforms position ADV heads above the seafloor to make mid-depth turbulence measurements. The inertial measurements from the IMU allows for removal of mooring motion in post processing. The mooring and buoy motion has been removed from the stream-wise and vertical velocity signals (u, w). The lateral (v) velocity has some 'persistent motion contamination' due to mooring sway. The TTM was deployed with one ADV, it's position was: 48 09.145', -122 41.209' The StableMoor was deployed twice, the first time it was deployed in 'wing-mode' with two ADVs ('Port' and 'Star') at: 48 09.166', -122 41.173' The second StableMoor deployment was in 'Nose' mode with one ADV at: 48 09.166', -122 41.174' Units ----- - Velocity data (_u, urot, uacc) is in m/s. - Acceleration (Accel) data is in m/s^2. - Angular rate (AngRt) data is in rad/s. - The components of all vectors are in 'ENU' orientation. That is, the first index is True East, the second is True North, and the third is Up (vertical). - All other quantities are in the units defined in the Nortek Manual. Motion correction and rotation into the ENU earth reference frame was performed using the Python-based open source DOLfYN library (http://lkilcher.github.io/dolfyn/). Details on motion correction can be found there. Additional details on TTM measurements at this site can be found in the included Marine Energy Technology Symposium paper.

  15. Admiralty Inlet Advanced Turbulence Measurements: June 2014

    DOE Data Explorer

    Kilcher, Levi

    2014-06-30

    This data is from measurements at Admiralty Head, in Admiralty Inlet (Puget Sound) in June of 2014. The measurements were made using Inertial Motion Unit (IMU) equipped ADVs mounted on Tidal Turbulence Mooring's (TTMs). The TTM positions the ADV head above the seafloor to make mid-depth turbulence measurements. The inertial measurements from the IMU allows for removal of mooring motion in post processing. The mooring motion has been removed from the stream-wise and vertical velocity signals (u, w). The lateral (v) velocity has some 'persistent motion contamination' due to mooring sway. Each ttm was deployed with two ADVs. The 'top' ADV head was positioned 0.5m above the 'bottom' ADV head. The TTMs were placed in 58m of water. The position of the TTMs were: ttm01 : (48.1525, -122.6867) ttm01b : (48.15256666, -122.68678333) ttm02b : (48.152783333, -122.686316666) Deployments TTM01b and TTM02b occurred simultaneously and were spaced approximately 50m apart in the cross-stream direction. Units ----- - Velocity data (_u, urot, uacc) is in m/s. - Acceleration (Accel) data is in m/s^2. - Angular rate (AngRt) data is in rad/s. - The components of all vectors are in 'ENU' orientation. That is, the first index is True East, the second is True North, and the third is Up (vertical). - All other quantities are in the units defined in the Nortek Manual. Motion correction and rotation into the ENU earth reference frame was performed using the Python-based open source DOLfYN library (http://lkilcher.github.io/dolfyn/). Details on motion correction can be found there. Additional details on TTM measurements at this site can be found in the included Marine Energy Technology Symposium paper.

  16. Investigation of Unsteady Flow Interaction Between an Ultra-Compact Inlet and a Transonic Fan

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Rabe, Douglas; Scribben, Angie

    2015-01-01

    In the present study, unsteady flow interaction between an ultra-compact inlet and a transonic fan stage is investigated. Future combat aircraft require ultra-compact inlet ducts as part of an integrated, advanced propulsion system to improve air vehicle capability and effectiveness to meet future mission needs. The main purpose of the study is to advance the current understanding of the flow interaction between two different ultra-compact inlets and a transonic fan for future design applications. Both URANS and LES approaches are used to calculate the unsteady flow field and are compared with the available measured data. The present study indicates that stall inception is mildly affected by the distortion pattern generated by the inlet with the current test set-up. The numerical study indicates that the inlet distortion pattern decays significantly before it reaches the fan face for the current configuration. Numerical results with a shorter distance between the inlet and fan show that counter-rotating vortices near the rotor tip due to the serpentine diffuser affects fan characteristics significantly.

  17. Trapping the Pasture Odorscape Using Open-Air Solid-Phase Micro Extraction, a Tool to Assess Grassland Value

    PubMed Central

    Cornu, Agnès; Farruggia, Anne; Leppik, Ene; Pinier, Centina; Fournier, Florence; Genoud, David; Frérot, Brigitte

    2015-01-01

    Besides supporting cattle feeding, grasslands are home to a diversity of plants and insects that interact with each other by emitting volatile compounds. The aim of this work was to develop a method to determine permanent grassland odorscape and relate it to flower-visiting insects. Two grasslands were chosen for their contrasting levels of botanical diversity, resulting from differing grazing managements. Measurements were made over two periods of three consecutive days at the beginning of grazing, and just after the cows had left the plots. Volatile compounds were trapped using solid-phase microextraction (SPME) fibers exposed eight hours a day in three exclosures per plot, and then analyzed by gas-chromatography-mass spectrometry (GC-MS). Insects were trapped using pan traps and a net, sorted and counted. The open air SPME method yielded volatile compound profiles that were richer than maize field profiles, comprising the common green leaf volatiles (GLV) and more specific ones. Differences between the odorscapes of the two grasslands were found, but they were not as marked as expected from their botanical composition. By contrast, there were sharp differences between the two periods, resulting from the combined effects of changes in weather conditions, plant phenological stage and grazing progress. Several correlations between insect counts and volatile compounds were found. Although their correlation coefficients were low, some of them were confirmed when tested by Spearman rank correlation, and could be logically explained. This method of grassland odorscape deserves to be developed because it can provide information on many aspects of grassland function and on the stresses that grassland plants undergo. PMID:26536369

  18. Trapping the Pasture Odorscape Using Open-Air Solid-Phase Micro Extraction, a Tool to Assess Grassland Value.

    PubMed

    Cornu, Agnès; Farruggia, Anne; Leppik, Ene; Pinier, Centina; Fournier, Florence; Genoud, David; Frérot, Brigitte

    2015-01-01

    Besides supporting cattle feeding, grasslands are home to a diversity of plants and insects that interact with each other by emitting volatile compounds. The aim of this work was to develop a method to determine permanent grassland odorscape and relate it to flower-visiting insects. Two grasslands were chosen for their contrasting levels of botanical diversity, resulting from differing grazing managements. Measurements were made over two periods of three consecutive days at the beginning of grazing, and just after the cows had left the plots. Volatile compounds were trapped using solid-phase microextraction (SPME) fibers exposed eight hours a day in three exclosures per plot, and then analyzed by gas-chromatography-mass spectrometry (GC-MS). Insects were trapped using pan traps and a net, sorted and counted. The open air SPME method yielded volatile compound profiles that were richer than maize field profiles, comprising the common green leaf volatiles (GLV) and more specific ones. Differences between the odorscapes of the two grasslands were found, but they were not as marked as expected from their botanical composition. By contrast, there were sharp differences between the two periods, resulting from the combined effects of changes in weather conditions, plant phenological stage and grazing progress. Several correlations between insect counts and volatile compounds were found. Although their correlation coefficients were low, some of them were confirmed when tested by Spearman rank correlation, and could be logically explained. This method of grassland odorscape deserves to be developed because it can provide information on many aspects of grassland function and on the stresses that grassland plants undergo.

  19. Assessing Resistance to Change During Shifting from Legacy to Open Web-Based Systems in the Air Transport Industry

    NASA Astrophysics Data System (ADS)

    Brewer, Denise

    The air transport industry (ATI) is a dynamic, communal, international, and intercultural environment in which the daily operations of airlines, airports, and service providers are dependent on information technology (IT). Many of the IT legacy systems are more than 30 years old, and current regulations and the globally distributed workplace have brought profound changes to the way the ATI community interacts. The purpose of the study was to identify the areas of resistance to change in the ATI community and the corresponding factors in change management requirements that minimize product development delays and lead to a successful and timely shift from legacy to open web-based systems in upgrading ATI operations. The research questions centered on product development team processes as well as the members' perceived need for acceptance of change. A qualitative case study approach rooted in complexity theory was employed using a single case of an intercultural product development team dispersed globally. Qualitative data gathered from questionnaires were organized using Nvivo software, which coded the words and themes. Once coded, themes emerged identifying the areas of resistance within the product development team. Results of follow-up interviews with team members suggests that intercultural relationship building prior to and during project execution; focus on common team goals; and, development of relationships to enhance interpersonal respect, understanding and overall communication help overcome resistance to change. Positive social change in the form of intercultural group effectiveness evidenced in increased team functioning during major project transitions is likely to result when global managers devote time to cultural understanding.

  20. General Investigation of Tidal Inlets: Stability of Selected United States Tidal Inlets

    DTIC Science & Technology

    1991-09-01

    years, the US Army Corps of Engineers, through its Civil Works program, has sponsored research into the behavior and character- istics of tidal inlets...73 5 50 Siletz, OR 7-39 to 2-76 4 51 Netarts, OR 7-53 to 7-73 4 Report Organizacion 8. Previous research on tidal inlet stability is summarized in Part...I. 1928. "Inlets on Sandy Coasts," Proceedings of the American Society of Civil Engineers, Vol LIV, pp 505-553. Bruun, P. 1967. Tidal Inlets and

  1. MTR, TRA603. SUBBASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER ...

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

    MTR, TRA-603. SUB-BASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER (NORTH SIDE) AND AIR (SOUTH SIDE). RABBIT CANAL AND BULKHEADS. SUMPS AND DRAINS. BLAW-KNOX 3150-3-7, 3/1950. INL INDEX NO. 531-0603-00-098-100006, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  2. Liquefied Bleed for Stability and Efficiency of High Speed Inlets

    NASA Technical Reports Server (NTRS)

    Saunders, J. David; Davis, David; Barsi, Stephen J.; Deans, Matthew C.; Weir, Lois J.; Sanders, Bobby W.

    2014-01-01

    A mission analysis code was developed to perform a trade study on the effectiveness of liquefying bleed for the inlet of the first stage of a TSTO vehicle. By liquefying bleed, the vehicle weight (TOGW) could be reduced by 7 to 23%. Numerous simplifying assumptions were made and lessons were learned. Increased accuracy in future analyses can be achieved by: Including a higher fidelity model to capture the effect of rescaling (variable vehicle TOGW). Refining specific thrust and impulse models ( T m a and Isp) to preserve fuel-to-air ratio. Implementing LH2 for T m a and Isp. Correlating baseline design to other mission analyses and correcting vehicle design elements. Implementing angle-of-attack effects on inlet characteristics. Refining aerodynamic performance (to improve L/D ratio at higher Mach numbers). Examining the benefit with partial cooling or densification of the bleed air stream. Incorporating higher fidelity weight estimates for the liquefied bleed system (heat exchange and liquid storage versus bleed duct weights) could be added when more fully developed. Adding trim drag or 6-degree-of-freedom trajectory analysis for higher fidelity. Investigating vehicle optimization for each of the bleed configurations.

  3. Parametric Inlet Tested in Glenn's 10- by 10-Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Davis, David O.; Solano, Paul A.

    2005-01-01

    The Parametric Inlet is an innovative concept for the inlet of a gas-turbine propulsion system for supersonic aircraft. The concept approaches the performance of past inlet concepts, but with less mechanical complexity, lower weight, and greater aerodynamic stability and safety. Potential applications include supersonic cruise aircraft and missiles. The Parametric Inlet uses tailored surfaces to turn the incoming supersonic flow inward toward an axis of symmetry. The terminal shock spans the opening of the subsonic diffuser leading to the engine. The external cowl area is smaller, which reduces cowl drag. The use of only external supersonic compression avoids inlet unstart--an unsafe shock instability present in previous inlet designs that use internal supersonic compression. This eliminates the need for complex mechanical systems to control unstart, which reduces weight. The conceptual design was conceived by TechLand Research, Inc. (North Olmsted, OH), which received funding through NASA s Small-Business Innovation Research program. The Boeing Company (Seattle, WA) also participated in the conceptual design. The NASA Glenn Research Center became involved starting with the preliminary design of a model for testing in Glenn s 10- by 10-Foot Supersonic Wind Tunnel (10 10 SWT). The inlet was sized for a speed of Mach 2.35 while matching requirements of an existing cold pipe used in previous inlet tests. The parametric aspects of the model included interchangeable components for different cowl lip, throat slot, and sidewall leading-edge shapes and different vortex generator configurations. Glenn researchers used computational fluid dynamics (CFD) tools for three-dimensional, turbulent flow analysis to further refine the aerodynamic design.

  4. Turbofan blade stresses induced by the flow distortion of a VTOL inlet at high angles of attack

    NASA Technical Reports Server (NTRS)

    Williams, R. C.; Diedrich, J. H.; Shaw, R. J.

    1983-01-01

    A 51-cm-diameter turbofan with a tilt-nacelle VTOL inlet was tested in the Lewis Research Center's 9- by 15-Ft Low Speed Wind Tunnel at velocities up to 72 m/s and angles of attack up to 120 deg. Fan-blade vibratory stress levels were investigated over a full aircraft operating range. These stresses were due to inlet air flow distortion resulting from (1) internal flow separation in the inlet, and (2) ingestion of the exterior nacelle wake. Stress levels are presented, along with an estimated safe operating envelope, based on infinite blade fatigue life.

  5. Turbine Inlet Analysis of Injected Water Droplet Behavior

    NASA Astrophysics Data System (ADS)

    Hargrave, Kevin

    Gas turbines have become widely used in the generation of power for cities. They are used all over the world and must operate under a wide variety of ambient conditions. Every turbine has a temperature at which it operates at peak capacity. In order to attain this temperature in the hotter months various cooling methods are used such as refrigeration inlet cooling systems, evaporative methods, and thermal energy storage systems. One of the more widely used is the evaporative systems because it is one of the safest and easiest to utilize method. However, the behavior of water droplets within the inlet to the turbine has not been extensively studied or documented. It is important to understand how the droplets behave within the inlet so that water droplets above a critical diameter will not enter the compressor and cause damage to the compressor blades. In order to do this a FLUENT simulation was constructed in order to determine the behavior of the water droplets and if any droplets remain at the exit of the inlet, along with their size. In order to do this several engineering drawings were obtained from SRP and studies in order to obtain the correct dimensions. Then the simulation was set up using data obtained from SRP and Parker-Hannifin, the maker of the spray nozzles. Then several sets of simulations were run in order to see how the water droplets behaved under various conditions. These results were then analyzed and quantified so that they could be easily understood. The results showed that the possible damage to the compressor increased with increasing temperature at a constant relative humidity. This is due in part to the fact that in order to keep a constant relative humidity at varying temperatures the mass fraction of water vapor in the air must be changed. As temperature increases the water vapor mass fraction must increase in order to maintain a constant relative humidity. This in turn makes it slightly increases the evaporation time of the water

  6. Investigation of Flow Instabilities in the Inlet Ducts of DP-1C VTOL Aircraft

    NASA Technical Reports Server (NTRS)

    Lepicovsky, Jan

    2008-01-01

    An investigation of flow instabilities in the inlet ducts of a two-engine vertical takeoff and landing aircraft DP-1C is described in this report. Recent tests revealed that the engines stall during run ups while the aircraft is operating on the ground. These pop stalls occurred at relatively low power levels, sometimes as low as 60 percent of the engine full speed. Inability to run the engines up to the full speed level is attributed to in-ground effects associated with hot gas ingestion. Such pop stalls were never experienced when the aircraft was tested on a elevated grid platform, which ensured that the aircraft was operating in out-of-the-ground-effect conditions. Based on available information on problems experienced with other vertical takeoff and landing aircraft designs, it was assumed that the engine stalls were caused by partial ingestion of hot gases streaming forward from the main exit nozzle under the aircraft inlets, which are very close to the ground. It was also suggested that the nose wheel undercarriage, located between the inlets, may generate vortices or an unstable wake causing intense mixing of hot exit gases with incoming inlet flow, which would enhance the hot gas ingestion. After running a short three-day series of tests with fully instrumented engine inlets, it is now believed the most probable reason for engine pop stalls are random ingestions of a vortex generated between the two streams moving in opposite directions: outbound hot gas stream from the main nozzle close to the ground and inbound inlet flow above. Originally, the vortex is in a horizontal plane. However, at a certain velocity ratio of these two streams, the vortex attaches either to the ground or the aircraft surface at one end and the other end is swallowed by one of the aircraft inlets. Once the vortex enters the inlet duct, a puff of hot air can be sucked through the vortex core into the engine, which causes a serious inlet flow field distortion followed by an engine

  7. Forward Operating Base Salerno: Inadequate Planning Resulted in $5 Million Spent for Unused Incinerators and the Continued Use of Potentially Hazardous Open-Air Burn Pit Operations

    DTIC Science & Technology

    2013-04-01

    communications; paving and walkways; and security fencing .2 At the time the contract was awarded, the base was primarily using open-air burn pit...and the effects they may have on various organs and body systems such as the adrenal glands, lungs , liver, and stomach. See Epidemiological Studies...Construct storm drainage system $37,869 $0 $37,869 0013 Construct anti-terrorism measures and fencing $126,206 ($10,985) $115,221 0014 Defense Base

  8. 33 CFR 80.703 - Little River Inlet, SC to Cape Romain, SC.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Inlet, a line drawn parallel with the general trend of the highwater shoreline across Hog Inlet; thence... the general trend of the highwater shoreline across Midway Inlet, Pawleys Inlet, and North Inlet....

  9. Diagnosis of abnormal patterns in multivariate microclimate monitoring: a case study of an open-air archaeological site in Pompeii (Italy).

    PubMed

    Merello, Paloma; García-Diego, Fernando-Juan; Zarzo, Manuel

    2014-08-01

    Chemometrics has been applied successfully since the 1990s for the multivariate statistical control of industrial processes. A new area of interest for these tools is the microclimatic monitoring of cultural heritage. Sensors record climatic parameters over time and statistical data analysis is performed to obtain valuable information for preventive conservation. A case study of an open-air archaeological site is presented here. A set of 26 temperature and relative humidity data-loggers was installed in four rooms of Ariadne's house (Pompeii). If climatic values are recorded versus time at different positions, the resulting data structure is equivalent to records of physical parameters registered at several points of a continuous chemical process. However, there is an important difference in this case: continuous processes are controlled to reach a steady state, whilst open-air sites undergo tremendous fluctuations. Although data from continuous processes are usually column-centred prior to applying principal components analysis, it turned out that another pre-treatment (row-centred data) was more convenient for the interpretation of components and to identify abnormal patterns. The detection of typical trajectories was more straightforward by dividing the whole monitored period into several sub-periods, because the marked climatic fluctuations throughout the year affect the correlation structures. The proposed statistical methodology is of interest for the microclimatic monitoring of cultural heritage, particularly in the case of open-air or semi-confined archaeological sites.

  10. Comparison of open and controlled pollinated pine families for susceptibility to air pollution, acid rain, and fusiform rust. Progress report

    SciTech Connect

    Chevone, B.; Powers, H.R. Jr.

    1982-10-01

    Loblolly pine seedlings were fumigated with SO/sub 2/, ozone, and a combination of SO/sub 2/ and ozone to determine the relative susceptibility of different strains to air pollution and to fusiform rust. There seems to be no relationship between susceptibility to air pollution and to fusiform rust, indicating it should be possible to select strains resistant to both fusiform rust and air pollution. (ACR)

  11. Influence of the penstock design on the operation of the inlet spherical valves

    NASA Astrophysics Data System (ADS)

    Kolesnikov, A.; Nikiforov, A.

    2014-03-01

    Spherical valves are supplied for high-head turbines. The drive of spherical valves designed and manufactured by Power Machines/LMZ provides opening by means of servomotors, and closing under the action of the moment created by counterweights. Selection of parameters for the spherical valve and its design are based on the assumption continuity of the water flow entering the turbine through the penstock. In case, when two or more hydro-units are installed at the HPP, the penstocks usually have pipe bifurcations (Fig.1). The design of the penstock should provide a uniform supply of water to all units without spin, rupture of continuity and pulsation. Given in the paper is an example of the HPP with two (2) hydro-units equipped with inlet spherical valves. In the course of operation valve rotor oscillations with different periods in time (T ≈ 15 sec.) were detected. When analyzing, no faults in the valve design and its mechanism of operation were detected. In the course of the tests, vibration parameters of the spherical valves were determined in the following operating conditions: each of the hydro-units running separately and both of them running simultaneously for different power output values. Based on the test results, operating conditions with maximum vibration of were located. The reasons of surging of perturbing forces acting on the rotor of the spherical valve were detected in the course of analysis of the penstock design. Possibility of accumulation of air at the penstock pipe bifurcations was found. When the air transported by the water achieved its critical value, this air appeared to be the cause of instability in the valve operation. The attention was drawn to necessity of taking into account this circumstance when designing penstock pipe bifurcations.

  12. Inlet contour and flow effects on radiation

    NASA Technical Reports Server (NTRS)

    Ville, J. M.; Silcox, R. J.

    1980-01-01

    An experimental investigation of sound radiation from inlets with different contours with and without flow is being conducted to study the possibility of reducing noise radiated by aircraft engines. For each inlet configuration, complex directivity patterns and complex pressure reflection coefficients are measured as a function of a single space-time structure of the wave (up to a frequency of 4000Hz and an azimuthal wave number 6) and of flow velocity (up to Mach number 0.4) in a cylindrical duct located downstream the inlet. Experimental results of radiation from an unflanged duct are compared with theory. Effect of inlet contour and flow are deduced by comparing respectively unflanged duct and bellmouth measurements and, no flow and flow measurements with the bellmouth. Results are presented which indicate that the contour effect is significant near the cut-on frequency of a mode and emphasize the necessity for taking into account the inlet geometry in a radiation prediction. These results show also that internal flow has a weak effect on the amplitude of the directivity pattern

  13. Analysis of Buzz in a Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.

    2012-01-01

    A dual-stream, low-boom supersonic inlet designed for use on a small, Mach 1.6 aircraft was tested experimentally in the 8- by 6-Foot Supersonic Wind Tunnel (SWT) at the NASA Glenn Research Center (GRC). The tests showed that the inlet had good recovery and stable operation over large mass flow range. The inlet went into buzz at mass flows well below that needed for engine operation, and the experiments generated a wealth of data during buzz. High frequency response pressure measurements and high-speed schlieren videos were recorded for many buzz events. The objective of the present work was to use computational fluid dynamics (CFD) to predict some of the experimental data taken during buzz, compare those predictions to the experimental data, and to use both datasets to explain the physics of the buzz cycle. The calculations were done with the Wind-US CFD code using a second-order time-accurate differencing scheme and the SST turbulence model. Computed Mach number contours were compared with schlieren images, and ensemble-averaged unsteady pressures were compared to data. The results showed that the buzz cycle consisted partly of spike buzz, an unsteady oscillation of the main shock at the spike tip while the inlet pressure dropped, and partly of choked flow while the inlet repressurized. Most of the results could be explained by theory proposed by Dailey in 1954, but did not support commonly used acoustic resonance explanations.

  14. Views to the past: Faunal and geophysical analysis of the open-air Upper Paleolithic site of Verberie

    NASA Astrophysics Data System (ADS)

    Thompson, Jason Randall

    , real-time process of prey item evaluation. Not all animals are equal in nutritional terms hence not all carcasses are evaluated equally. A Ground-penetrating radar study is also included to answer two substantive questions: 1) How representative of the entire site assemblage is the currently excavated sample?; and 2) Are there data visible that are indicative of multiple, interacting "households" as at Pincevent, or does the material scale, configuration, and distribution appear limited to a single household? GPR has proven to be a highly informative and productive near-surface geophysical technique for investigating many archaeological sites, and this research details one of the earliest such applications in a Paleolithic open-air context. At VBC, GPR was highly effective in locating anthropogenic accumulations of unexcavated archaeological materials which were field-tested through excavations during the 2009 field season.

  15. Cyclic organic peroxides identification and trace analysis by Raman microscopy and open-air chemical ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Pena-Quevedo, Alvaro Javier

    The persistent use of cyclic organic peroxides in explosive devices has increased the interest in study these compounds. Development of methodologies for the detection of triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD) has become an urgent priority. However, differences in physical properties between cyclic organic peroxides make difficult the development of a general method for peroxide analysis and detection. Following this urgency, the first general technique for the analysis of any peroxide, regarding its structural differences is reported. Characterization and detection of TATP and HMTD was performed using an Open-Air Chemical Ionization High-Resolution Time-of-Flight Mass Spectrometer. The first spectrometric analysis for tetramethylene diperoxide dicarbamide (TMDD) and other nitrogen based peroxides using Raman Microscopy and Mass Spectrometry is reported. Analysis of cyclic peroxides by GC-MS was also conducted to compare results with OACI-HRTOF data. In the OACI mass spectrum, HMTD showed a clear signal at m/z 209 MH + and a small adduct peak at m/z 226 [M+NH4]+ that allowed its detection in commercial standard solutions and lab made standards. TMDD presented a molecular peak of m/z 237 MH+ and an adduct peak of m/z 254 [M+NH4]+. TATP showed a single peak at m/z 240 [M+NH4]+, while the peak of m/z 223 or 222 was completely absent. This evidence suggests that triperoxides are stabilized by the ammonium ion. TATP samples with deuterium enrichment were analyzed to compare results that could differentiate from HMTD. Raman microscopy was used as a complementary characterization method and was an essential tool for cyclic peroxides identification, particularly for those which could not be extensively purified. All samples were characterized by Raman spectroscopy to confirm the Mass Spectrometry results. Peroxide O-O vibrations were observed around 750-970 cm-1. D18-TATP studies had identified ketone triperoxide nu(O-O) vibration around

  16. Solid sorbent air sampler

    NASA Astrophysics Data System (ADS)

    Galen, T. J.

    1986-04-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  17. Solid sorbent air sampler

    NASA Technical Reports Server (NTRS)

    Galen, T. J. (Inventor)

    1986-01-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  18. Distribution and sources of polychlorinated biphenyls in Woods Inlet, Lake Worth, Fort Worth, Texas, 2003

    USGS Publications Warehouse

    Besse, Richard E.; Van Metre, Peter C.; Wilson, Jennifer T.

    2005-01-01

    Woods Inlet is a flooded stream channel on the southern shore of Lake Worth along the western boundary of Air Force Plant 4 in Fort Worth, Texas, where elevated polychlorinated biphenyl (PCB) concentrations in sediment were detected in a previous study. In response, the U.S. Geological Survey, in cooperation with the U.S. Air Force, conducted a study in 2003 to map the extent of elevated PCB concentrations in Woods Inlet and to identify possible sources (or more specifically, source areas) of PCBs in the watershed of Woods Inlet. Three gravity cores (penetration to pre-reservoir sediment at three sites) and 17 box cores (surficial bottom sediment samples) were collected in Woods Inlet. Suspended sediment in stormwater runoff and streambed sediment were sampled in tributaries to Woods Inlet following storms. Assemblages of PCB congeners in surficial inlet sediments and suspended and streambed sediments were analyzed to indicate sources of PCBs in the inlet sediments on the basis of chemical signatures of PCBs. Woods Inlet receives runoff primarily from three tributaries: (1) Gruggs Park Creek, (2) the small unnamed creek that drains a Texas National Guard maintenance facility, called TNG Creek for this report, and (3) Meandering Road Creek. Twenty-seven of 209 possible PCB congeners were analyzed. The sum of the congeners was used as a measure of total PCB. The spatial distribution of total PCB concentrations in the inlet indicates that most PCBs are originating in the Meandering Road Creek watershed. Peak total PCB concentrations in the three gravity cores occurred at depths corresponding to sediment deposition dates of about 1960 for two of the cores and about 1980 for the third core. The magnitudes of peak total PCB concentrations in the gravity cores followed a spatial distribution generally similar to that of surficial bottom sediment concentrations. Total PCB concentrations in suspended and streambed sediment varied greatly between sites and indicated a likely

  19. Seasonal Change in Nearshore and Channel Morphology at Packery Channel, A New Inlet Serving Corpus Christi, Texas

    DTIC Science & Technology

    2011-01-01

    Channel enjoy a variety of activities including fishing, boating, swimming, snorkeling, and kayaking . Consistently strong wind and a weaker longshore...south of Bob Hall Pier. Fish Pass is an artificial inlet that opened in 1978 and began closing naturally soon after construction with complete closure...the Corpus Christi Water Exchange Pass. Rapid natural closure of the Fish Pass created doubt about the stability of the planned inlet at Packery

  20. 49 CFR 178.338-7 - Openings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.338-7 Openings. (a) The inlet to the...

  1. Experimental Investigation of a Hypersonic Inlet with Variable Sidewall for Flow Control

    NASA Astrophysics Data System (ADS)

    Rolim, T. C.; Lu, F. K.

    The main function of a scramjet inlet is to decelerate and compress the air for subsequent reaction with the fuel inside the combustor and, of course, contribute toward meeting the thrust requirement for the entire mission by providing adequate mass flow. It is desirable that the inlet be lightweight and that its geometry be capable of producing a uniform flow in an appropriate state to permit efficient mixing and subsequent combustion. Engine cycle analysis indicates that high contraction ratios CR are desirable for achieving high overall engine efficiency.

  2. Numerical simulation of scramjet inlet flow fields

    NASA Technical Reports Server (NTRS)

    Kumar, Ajay

    1986-01-01

    A computer program was developed to analyze supersonic combustion ramjet (scramjet) inlet flow fields. The program solves the three-dimensional Euler or Reynolds averaged Navier-Stokes equations in full conservation form by either the fully explicit or explicit-implicit, predictor-corrector method of MacCormack. Turbulence is modeled by an algebraic eddy-viscosity model. The analysis allows inclusion of end effects which can significantly affect the inlet flow field. Detailed laminar and turbulent flow results are presented for a symmetric-wedge corner, and comparisons are made with the available experimental results to allow assessment of the program. Results are then presented for two inlet configurations for which experimental results exist at the NASA Langley Research Center.

  3. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, R.F.; Dietrich, D.D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability is disclosed. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three. 6 figs.

  4. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, Robert F.; Dietrich, Daniel D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three.

  5. Analysis of thrust augmentation of turbojet engines by water injection at compressor inlet including charts for calculating compression processes with water injection

    NASA Technical Reports Server (NTRS)

    Wilcox, E Clinton; Trout, Arthur M

    1951-01-01

    A psychrometric chart having total pressure (sum of partial pressures of air and water vapor) as a variable, a Mollier diagram for air saturated with water vapor, and charts showing the thermodynamic properties of various air-water vapor and exhaust gas-water vapor mixtures are presented as aids in calculating the thrust augmentation of a turbojet engine resulting from the injection of water at the compressor inlet. Curves are presented that show the theoretical performance of the augmentation method for various amounts of water injected and the effects of varying flight Mach number, altitude, ambient-air temperature, ambient relative humidity, compressor pressure ratio, and inlet-diffuser efficiency. Numerical examples, illustrating the use of the psychrometric chart and the Mollier diagram in calculating both compressor-inlet and compressor-outlet conditions when water is injected at the compressor inlet, are presented.

  6. Investigation of High-Subsonic Performance Characteristics of a 12 Degree 21-Inch Conical Diffuser, Including the Effects of Change in Inlet-Boundary-Layer Thickness

    NASA Technical Reports Server (NTRS)

    Copp, Martin R.; Klevatt, Paul L.

    1950-01-01

    Investigations were conducted of a 12 degree 21-inch conical diffuser of 2:l area ratio to determine the interrelation of boundary layer growth and performance characteristics. surveys were made of inlet and exit from, longitudinal static pressures were recorded, and velocity profiles were obtained through an inlet Reynolds number range, determined From mass flows and based on inlet diameter of 1.45 x 10(exp 6) to 7.45 x 10(exp 6) and a Mach number range of 0.11 to approximately choking. These investigations were made to two thicknesses of inlet boundary layer. The mean value, over the entire range of inlet velocities, of the displacement thickness of the thinner inlet boundary layer was approximately 0.035 inch and that of the thicker inlet boundary layer was approximately six times this value. The loss coefficient in the case of the thinner inlet boundary layer had a value between 2 to 3 percent of the inlet impact pressure over most of the air-flow range. The loss coefficient with the thicker inlet boundary layer was of the order of twice that of the thinner inlet boundary layer at low speeds and approximately three times at high speeds. In both cases the values were substantially less than those given in the literature for fully developed pipe flow. The static-pressure rise for the thinner inlet boundary layer was of the order of 95 percent of that theoretically possible over the entire speed range. For the thicker inlet boundary layer the static pressure rise, as a percentage of that theoretically possible, ranged from 82 percent at low speeds to 68 percent at high speeds.

  7. The European Fixed point Open Ocean Observatory network (FixO3): Multidisciplinary observations from the air-sea interface to the deep seafloor

    NASA Astrophysics Data System (ADS)

    Lampitt, Richard; Cristini, Luisa; Alexiou, Sofia

    2015-04-01

    The Fixed point Open Ocean Observatory network (FixO3, http://www.fixo3.eu/ ) integrates 23 European open ocean fixed point observatories and improves access to these infrastructures for the broader community. These provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Started in September 2013 with a budget of 7 Million Euros over 4 years, the project has 29 partners drawn from academia, research institutions and SME's coordinated by the National Oceanography Centre, UK. Here we present the programme's achievements in the 18 months and the activities of the 12 Work Packages which have the objectives to: • integrate and harmonise the current procedures and processes • offer free access to observatory infrastructures to those who do not have such access, and free and open data services and products • innovate and enhance the current capability for multidisciplinary in situ ocean observation Open ocean observation is a high priority for European marine and maritime activities. FixO3 provides important data and services to address the Marine Strategy Framework Directive and in support of the European Integrated Maritime Policy. FixO3 provides a strong integrated framework of open ocean facilities in the Atlantic from the Arctic to the Antarctic and throughout the Mediterranean, enabling an integrated, regional and multidisciplinary approach to understand natural and anthropogenic change in the ocean.

  8. Investigation of Unsteady Flow Interaction Between an Ultra-Compact Inlet and a Transonic Fan

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Rabe, Douglas; Scribben, Angie

    2015-01-01

    In the study presented, unsteady flow interaction between an ultra-compact inlet and a transonic fan stage is investigated. Future combat aircraft engines require ultra-compact inlet ducts as part of an integrated, advanced propulsion system to improve air vehicle capability and effectiveness to meet future mission needs. The main purpose of the current study is to advance the understanding of the flow interaction between a modern ultra-compact inlet and a transonic fan for future design applications. Many experimental/ analytical studies have been reported on the aerodynamics of compact inlets in aircraft engines. On the other hand, very few studies have been reported on the effects of flow distortion from these inlets on the performance of the following fan/compressor stages. The primary goal of the study presented is to investigate how flow interaction between an ultra-compact inlet and a transonic compressor influence the operating margin of the compressor. Both Unsteady Reynolds-averaged Navier-Stokes (URANS) and Large Eddy Simulation (LES) approaches are used to calculate the unsteady flow field, and the numerical results are used to study the flow interaction. The present study indicates that stall inception of the following compressor stage is affected directly based on how the distortion pattern evolves before it interacts with the fan/compressor face. For the present compressor, the stall initiates at the tip section with clean inlet flow and distortion pattern away from the casing itself seems to have limited impacts on the stall inception of the compressor. A counter-rotating swirl, which is generated due to flow separation inside the s-shaped compact duct, generates an increased flow angle near the blade tip. This increased flow angle near the rotor tip due to the secondary flow from the counter-rotating vortices is the primary reason for the reduced compressor stall margin.

  9. Investigation on Multiple-Pulse Propulsion Performance for a Parabolic Nozzle with Inlet Slit

    NASA Astrophysics Data System (ADS)

    Wen, Ming; Hong, Yanji; Song, Junling

    2011-11-01

    The multiple-pulse impulse coupling coefficient Cm is lower than the single pulse one with the same laser parameters. It is always explained that air recovery in nozzle does not work on time. Three kinds of parabolic nozzles are employed to improve air recovery in the experiments and simulation. There exist inlet slits on side wall of them with width of 1 mm, 2 mm, respectively. The curves of thrust and the process of flow fluid field are presented to study the slit effects on Cm under 20 Hz pulse frequency. The results show: an inlet slit can accelerate the air breathing process in the nozzle and Cm for each pulse exhibits a little variation; the lower Cm is obtained due to the increasing energy loss by a larger size slit; the flat-roofed nozzle gets higher Cm than others.

  10. Dynamic evaluation of airflow rates for a variable air volume system serving an open-plan office.

    PubMed

    Mai, Horace K W; Chan, Daniel W T; Burnett, John

    2003-09-01

    In a typical air-conditioned office, the thermal comfort and indoor air quality are sustained by delivering the amount of supply air with the correct proportion of outdoor air to the breathing zone. However, in a real office, it is not easy to measure these airflow rates supplied to space, especially when the space is served by a variable air volume (VAV) system. The most accurate method depends on what is being measured, the details of the building and types of ventilation system. The constant concentration tracer gas method as a means to determine ventilation system performance, however, this method becomes more complicated when the air, including the tracer gas is allowed to recirculate. An accurate measurement requires significant resource support in terms of instrumentation set up and also professional interpretation. This method deters regular monitoring of the performance of an airside systems by building managers, and hence the indoor environmental quality, in terms of thermal comfort and indoor air quality, may never be satisfactory. This paper proposes a space zone model for the calculation of all the airflow parameters based on tracer gas measurements, including flow rates of outdoor air, VAV supply, return space, return and exfiltration. Sulphur hexafluoride (SF6) and carbon dioxide (CO2) are used as tracer gases. After using both SF6 and CO2, the corresponding results provide a reference to justify the acceptability of using CO2 as the tracer gas. The validity of using CO2 has the significance that metabolic carbon dioxide can be used as a means to evaluate real time airflow rates. This approach provides a practical protocol for building managers to evaluate the performance of airside systems.

  11. Influence of combustion-preheating vitiation on operability of a hypersonic inlet

    NASA Astrophysics Data System (ADS)

    Liu, K.; Zhu, Y.; Gao, W.; Yang, J.; Jin, Y.; Wu, Y.

    2016-11-01

    Vitiation of the test flow with combustion products is inherent in combustion wind tunnels, and its effect on experimental results needs to be clarified. In this study, the influence of air vitiation on the startability and performance of a hypersonic inlet is investigated through two-dimensional (2D) numerical simulation. The study examines the vitiation effects introduced by carbon dioxide and water vapor, on the basis of maintaining the static pressure, static temperature and Mach number of the incoming flow. The starting Mach number limits of the inlet are estimated, and it is found that both of these vitiation components lower the starting limit of the inlet. This suggests that the experimental results acquired by tests in combustion wind tunnels overestimate the startability of an inlet and, therefore, combustion-preheated facilities may not be completely trusted in this respect. Deviations in the inlet performance caused by the vitiation are also detected. These are nevertheless minor as long as the flow is at the same started or unstarted condition. A further analysis reveals that it is mainly the increase in the heat capacity, and the resulting weaker shock/compression waves and shock-wave/boundary-layer interactions that account for the aforementioned effects.

  12. Supersonic Inlet with Pylons Set and Star-Shaped Forebody for Mixing, Combustion and Thrust Enhancement

    NASA Technical Reports Server (NTRS)

    Gilinsky, M.; Gonor, A. L.; Khaikine, V. A.; Blankson, I. M.

    2003-01-01

    Two new approaches are discussed in this paper for application in the Scramjet inlet of an air-breathing propulsion system: 1) In the first approach, the pylon set is installed in the rectangular inlet near the cowl front edge. For a quasi-axisymmetric inlet, a similar set is installed along the Star-shaped forebody axis. This set contains 3 - 4 airfoil-shaped strips or cross-sectional rings depending on the type of inlet. The inlets: rectangular, axisymmetric or star-shaped, are located at different distances from the forebody. Fuel injection takes place through these pylons, which provides for uniform mixing downstream. The locations, sizes and angles of these pylons are very important for efficient application. Optimal values of geometrical parameters were determined from multi-parametric NSE-based numerical simulations of the laminar and turbulent external/internal flows. These simulations have shown significant benefits for mixing, combustion and thrust of the proposed approach by comparison with traditional well-known designs. Experimental tests will be conducted soon at the NASA LaRC and Institute of Mechanics at Moscow State University. Preliminary estimates are very promising.

  13. Numerical analysis of flow features and operation characteristics of a rocket-based combined-cycle inlet in ejector mode

    NASA Astrophysics Data System (ADS)

    Shi, Lei; Liu, Xiaowei; He, Guoqiang; Qin, Fei; Wei, Xianggeng; Yang, Bin; Liu, Jie

    2016-10-01

    A ready-made central strut-based rocket-based combined-cycle (RBCC) engine was numerically investigated in the ejector mode. The flow features in the RBCC inlet and the matching characteristics between the inlet and the embedded rocket during different flight regimes were examined in detail. It was necessary to perform integrated numerical simulations in the ejector mode within considerable pressure far fields around the inlet/exhaust system. The observed flow features and operation characteristics in the RBCC inlet were strongly correlated with the flight conditions, inlet configuration, and operation of the embedded rocket. It was further found that the integrated function status of multiple factors significantly influenced the performance of the RBCC engine in the ejector mode. The two parameters that macroscopically affected the performance most were the air entrainment mass and the drag of the RBCC inlet. To improve these parameters, it is vital to employ an appropriate design of the RBCC inlet and establish the optimal flight trajectory of the flight vehicle.

  14. Design and operation considerations for attic inlets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving energy efficiency and environmental control in poultry facilities is essential for profitability. Increases in energy costs have prompted evaluation of solar energy systems and passive solar systems such as attic inlets have been adopted as a means to reduce fuel usage. Successful implem...

  15. Remote open-path cavity-ringdown spectroscopic sensing of trace gases in air, based on distributed passive sensors linked by km-long optical fibers.

    PubMed

    He, Yabai; Jin, Chunjiang; Kan, Ruifeng; Liu, Jianguo; Liu, Wenqing; Hill, Julian; Jamie, Ian M; Orr, Brian J

    2014-06-02

    A continuous-wave, rapidly swept cavity-ringdown spectroscopic technique has been developed for localized atmospheric sensing of trace gases at remote sites. It uses one or more passive open-path optical sensor units, coupled by optical fiber over distances of >1 km to a single transmitter/receiver console incorporating a photodetector and a swept-frequency diode laser tuned to molecule-specific near-infrared wavelengths. Ways to avoid interference from stimulated Brillouin scattering in long optical fibers have been devised. This rugged open-path system, deployable in agricultural, industrial, and natural atmospheric environments, is used to monitor ammonia in air. A noise-limited minimum detectable mixing ratio of ~11 ppbv is attained for ammonia in nitrogen at atmospheric pressure.

  16. 33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1240 Sinclair Inlet..., longitude 122°37′23″ West on the north shore of Sinclair Inlet; and latitude 47°32′52″ North, longitude 122°36′58″ West, on the south shore of Sinclair Inlet. (2) Area No. 2. That area of Sinclair Inlet to...

  17. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T. A. [Knoxville, TN

    2010-12-14

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  18. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T.A.

    2014-05-13

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  19. Mass independent kinetic energy reducing inlet system for vacuum environment

    DOEpatents

    Reilly, Peter T.A.

    2013-12-03

    A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

  20. Assessing Resistance to Change during Shifting from Legacy to Open Web-Based Systems in the Air Transport Industry

    ERIC Educational Resources Information Center

    Brewer, Denise

    2012-01-01

    The air transport industry (ATI) is a dynamic, communal, international, and intercultural environment in which the daily operations of airlines, airports, and service providers are dependent on information technology (IT). Many of the IT legacy systems are more than 30 years old, and current regulations and the globally distributed workplace have…

  1. Flow Control in a Compact Inlet

    NASA Astrophysics Data System (ADS)

    Vaccaro, John C.

    2011-12-01

    An experimental investigation of flow control, via various control jets actuators, was undertaken to eliminate separation and secondary flows in a compact inlet. The compact inlet studied was highly aggressive with a length-to-diameter ratio of 1.5. A brand new facility was designed and built to enable various actuation methodologies as well as multiple measurement techniques. Techniques included static surface pressure, total pressure, and stereoscopic particle image velocimetry. Experimental data were supplemented with numerical simulations courtesy of Prof. Kenneth Jansen, Dr. Onkar Sahni, and Yi Chen. The baseline flow field was found to be dominated by two massive separations and secondary flow structures. These secondary structures were present at the aerodynamic interface plane in the form of two counter-rotating vortices inducing upwash along centerline. A dominant shedding frequency of 350 Hz was measured both at the aerodynamic interface plane and along the lower surface of the inlet. Flow control experiments started utilizing a pair of control jets placed in streamwise locations where flow was found to separate. Tests were performed for a range of inlet Mach numbers from 0.2 to 0.44. Steady and unsteady static pressure measurements along the upper and lower walls of the duct were performed for various combinations of actuation. The parameters that were tested include the control jets momentum coefficient, their blowing ratio, the actuation frequency, as well as different combinations of jets. It was shown that using mass flux ratio as a criterion to define flow control is not sufficient, and one needs to provide both the momentum coefficient and the blowing ratio to quantify the flow control performance. A detailed study was undertaken on controlling the upstream separation point for an inlet Mach number of 0.44. Similar to the baseline flow field, the flow field associated with the activation of a two-dimensional control jet actuator was dominated by

  2. Fuel cell integral bundle assembly including ceramic open end seal and vertical and horizontal thermal expansion control

    DOEpatents

    Zafred, Paolo R [Murrysville, PA; Gillett, James E [Greensburg, PA

    2012-04-24

    A plurality of integral bundle assemblies contain a top portion with an inlet fuel plenum and a bottom portion containing a base support, the base supports a dense, ceramic air exhaust manifold having four supporting legs, the manifold is below and connects to air feed tubes located in a recuperator zone, the air feed tubes passing into the center of inverted, tubular, elongated, hollow electrically connected solid oxide fuel cells having an open end above a combustion zone into which the air feed tubes pass and a closed end near the inlet fuel plenum, where the open end of the fuel cells rest upon and within a separate combination ceramic seal and bundle support contained in a ceramic support casting, where at least one flexible cushion ceramic band seal located between the recuperator and fuel cells protects and controls horizontal thermal expansion, and where the fuel cells operate in the fuel cell mode and where the base support and bottom ceramic air exhaust manifolds carry from 85% to all of the weight of the generator.

  3. 30 CFR 75.524 - Electric face equipment; electric equipment used in return air outby the last open crosscut...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the last open crosscut; maximum level of alternating or direct electric current between frames of equipment. The maximum level of alternating or direct electric current that exists between the frames of any... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric face equipment; electric...

  4. 30 CFR 75.524 - Electric face equipment; electric equipment used in return air outby the last open crosscut...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the last open crosscut; maximum level of alternating or direct electric current between frames of equipment. The maximum level of alternating or direct electric current that exists between the frames of any... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric face equipment; electric...

  5. 30 CFR 75.524 - Electric face equipment; electric equipment used in return air outby the last open crosscut...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the last open crosscut; maximum level of alternating or direct electric current between frames of equipment. The maximum level of alternating or direct electric current that exists between the frames of any... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric face equipment; electric...

  6. 30 CFR 75.524 - Electric face equipment; electric equipment used in return air outby the last open crosscut...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the last open crosscut; maximum level of alternating or direct electric current between frames of equipment. The maximum level of alternating or direct electric current that exists between the frames of any... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric face equipment; electric...

  7. 30 CFR 75.524 - Electric face equipment; electric equipment used in return air outby the last open crosscut...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the last open crosscut; maximum level of alternating or direct electric current between frames of equipment. The maximum level of alternating or direct electric current that exists between the frames of any... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric face equipment; electric...

  8. Coal air turbine {open_quotes}CAT{close_quotes} program, Invention 604. Third quarter project report, April 1995--June 1995

    SciTech Connect

    Foster-Pegg, R.W.

    1995-07-31

    The primary objective of this {open_quotes}CAT{close_quotes} project is to complete a conceptual design of this unique new combination of existing technology with cost estimates to show that the {open_quotes}CAT{close_quotes} system offers the economic incentive with low technical risk for a plant to be built which will demonstrate its viability. The technologies involved in the components of a {open_quotes}CAT{close_quotes} plant are proven, and the integration of the components into a complete plant is the only new development activity involved. Industry and the Federal General Services Administration (GSA), require the demonstration of a {open_quotes}commercial plant{close_quotes} before the viability of a new concept is accepted. To satisfy this requirement and construction of a plant of commercially viable size in excess of 15 MW if cogeneration and above 30 MW if all power, is proposed. This plant will produce economical power and heat for the owner. The plant will operate a full commercial life and continue as an operating demonstration of the viability of the technology, gathering long term life and maintenance data, all adding to the credibility of the concept.

  9. Influence of inlet conditions on vortex characteristics

    NASA Astrophysics Data System (ADS)

    Essiptchouk, A.

    2011-09-01

    Vortex chambers are normally used for arc stabilization in linear plasma torches. In the present work, the effect of uniformity of the gas inlet channel distribution on the stabilizing characteristics of a swirled flow is studied numerically. The formation of a complex flow pattern with a toroidal recirculating flow area inside the vortex chamber is observed. For some regimes, two local maxima of the tangential velocity are observed in the middle section of the chamber. It is shown that an increment of the number of gas inlet channels leads to a more uniform gas input with disappearance of the second maximum, which increases the velocity amplification coefficient and, correspondingly, results in a better stabilizing effect. The obtained profiles of the radial distribution of the tangential velocity are compared with the results of Oseen's equation for an unconfined vortex.

  10. Large Eddy Simulation of Supersonic Inlet Flows

    DTIC Science & Technology

    1998-04-01

    SIMULATION OF SUPERSONIC INLET FLOWS 6. AUTHOR(S) PROF. PARVIZ MOIN PROF. SANJIVA K. LELE 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) STANFORD... Parviz Moin and Sanjiva K. Lele Stanford University Mechanical Engineering, Flow Physics & Computation Division Stanford, CA 94305-3030 Prepared...monitor. I am thankful to Professor Sanjiva Lele and Profes- sor Parviz Moin, and Keith Lucas for useful discussions! I am grateful to Professor Peter

  11. Gasdynamic Inlet Isolation in Rotating Detonation Engine

    DTIC Science & Technology

    2010-12-01

    ISOLATION IN ROTATING DETONATION ENGINE by Wei Han Eugene Lim December 2010 Thesis Co-Advisors: Jose O. Sinibaldi Christopher M. Brophy...COVERED Master’s Thesis 4. TITLE AND SUBTITLE Gasdynamic Inlet Isolation in Rotating Detonation Engine 6. AUTHOR(S) Wei Han Eugene Lim 5. FUNDING...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) The Rotating Detonation Engine (RDE) concept represents the next-generation of detonation -based

  12. Hydrologic transport of depleted uranium associated with open air dynamic range testing at Los Alamos National Laboratory, New Mexico, and Eglin Air Force Base, Florida

    SciTech Connect

    Becker, N.M.; Vanta, E.B.

    1995-05-01

    Hydrologic investigations on depleted uranium fate and transport associated with dynamic testing activities were instituted in the 1980`s at Los Alamos National Laboratory and Eglin Air Force Base. At Los Alamos, extensive field watershed investigations of soil, sediment, and especially runoff water were conducted. Eglin conducted field investigations and runoff studies similar to those at Los Alamos at former and active test ranges. Laboratory experiments complemented the field investigations at both installations. Mass balance calculations were performed to quantify the mass of expended uranium which had transported away from firing sites. At Los Alamos, it is estimated that more than 90 percent of the uranium still remains in close proximity to firing sites, which has been corroborated by independent calculations. At Eglin, we estimate that 90 to 95 percent of the uranium remains at test ranges. These data demonstrate that uranium moves slowly via surface water, in both semi-arid (Los Alamos) and humid (Eglin) environments.

  13. Investigation of "6X" Scramjet Inlet Configurations

    NASA Technical Reports Server (NTRS)

    Alter, Stephen J.

    2012-01-01

    This work represents an initial attempt to determine what, if any, issues arise from scaling demonstration supersonic combustion scramjets to a flight scale making the engine a viable candidate for both military weapon and civilian access to space applications. The original vehicle sizes tested and flown to date, were designed to prove a concept. With the proven designs, use of the technology for applications as weapon systems or space flight are only possible at six to ten times the original scale. To determine effects of scaling, computations were performed with hypersonic inlets designed to operate a nominal Mach 4 and Mach 5 conditions that are possible within the eight foot high temperature tunnel at NASA Langley Research Center. The total pressure recovery for these inlets is about 70%, while maintaining self start conditions, and providing operable inflow to combustors. Based on this study, the primary scaling effect detected is the strength of a vortex created along the cowl edge causing adverse boundary layer growth in the inlet.

  14. Construction of Open Burning Facility Moody Air Force Base, Georgia Environmental Assessment and Finding of No Significant Impact

    DTIC Science & Technology

    2009-01-01

    Force Manual (AFMAN) 91-201 restricts access within the explosive clear zone around the MSA to mission essential personnel, which would exclude...the combustion of coal and oil by steel mills, pulp and paper mills, and from non-ferrous smelters. High concentrations of SO2 can aggravate...Assessment -- Open Burning Facility 29 4. Industrial—265 acres • Base Civil Engineering shops • Munitions storage • Petroleum, oil , and

  15. 7. View north at back (canal side) of culvert inlet, ...

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

    7. View north at back (canal side) of culvert inlet, with canal bank completely removed. Background to foreground: back of inlet headwall with tops of high inlet barrels exposed; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall at site of former canal edge of canal bank; dewatered canal bed and plank sheathing on top of culvert barrels beneath canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  16. Open-loop control of combustion instabilities in a model gas turbine combustor*

    NASA Astrophysics Data System (ADS)

    Stone, Christopher; Menon, Suresh

    2003-05-01

    The effect of premixer-induced inlet swirl on the stability of a model swirl-stabilized, lean-premixed gas turbine combustor has been numerically investigated using the large-eddy simulation methodology. The unsteady vortex-flame and acoustic-flame interactions are captured in this study using a thin-flame model that includes an ability to account for the variation in inlet equivalence ratio. Comparisons are made, based on fluid particle trajectories, between the structure of the recirculation regions. It is shown that only for high swirl does a region of flow recirculation, often called vortex breakdown(VB), occur in the centreline region of the dump combustor. This VB region helps to stabilize the flame and results in significant attenuation of the fluctuating pressure amplitudes, p'. The reduced p' amplitudes are accompanied by reduced longitudinal flame-front oscillations and reduced coherence in the shed vortices. A methodology for open-loop control based on the modulation of incoming fuel-air equivalence ratio is investigated. It is demonstrated that combustor pressure fluctuations respond much more rapidly to these changes compared to earlier studies of inlet swirl number modulation. The impact of these changes on flame stability and overall dynamics is analysed and discussed. Finally, the impact of imperfect mixedness in the incoming fuel-air mixture is also analysed and it is shown that the pressure oscillation amplitude is actually reduced under these conditions.

  17. Entrainment by turbulent jets issuing from sharp-edged inlet round nozzles

    NASA Astrophysics Data System (ADS)

    Trabold, T. A.; Essen, E. B.; Obot, N. T.

    Experiments were carried out to determine entrainment rates by turbulent air jets generated with square-edged inlet round nozzles. A parametric study was made which included the effects of Reynolds number, nozzle length, partial confinement and geometry of the jet plenum chamber. Measurements were made for the region extending from the nozzle exit to 24 jet hole diameters downstream. There is a large difference in entrainment rate between jets generated with relatively short nozzles and those discharged through long tubes.

  18. Variable geometry for supersonic mixed-compression inlets

    NASA Technical Reports Server (NTRS)

    Sorensen, N. E.; Latham, E. A.; Smeltzer, D. B.

    1974-01-01

    Study of two-dimensional and axisymmetric supersonic mixed-compression inlet systems has shown that the geometry of both systems can be varied to provide adequate transonic airflow to satisfy the airflow demand of most jet engines. Collapsing geometry systems for both types of inlet systems provide a generous amount of transonic airflow for any design Mach number inlet system. However, the mechanical practicality of collapsing centerbodies for axisymmetric inlet systems is doubtful. Therefore, translating centerbody axisymmetric inlets with auxiliary airflow systems to augment the transonic airflow capability are an attractive alternative. Estimates show that the capture mass-flow ratio at Mach number 1.0 can be increased approximately 0.20 for a very short axisymmetric inlet system designed for Mach number 2.37. With this increase in mass-flow ratio, even variable-cycle engine transonic airflow demand can be matched without oversizing the inlet at the design Mach number.

  19. Fixed point Open Ocean Observatory network (FixO3): Multidisciplinary observations from the air-sea interface to the deep seafloor

    NASA Astrophysics Data System (ADS)

    Lampitt, Richard; Cristini, Luisa

    2014-05-01

    The Fixed point Open Ocean Observatory network (FixO3) seeks to integrate the 23 European open ocean fixed point observatories and to improve access to these key installations for the broader community. These will provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Coordinated by the National Oceanography Centre, UK, FixO3 builds on the significant advances achieved through the previous Europe-funded FP7 programmes EuroSITES, ESONET and CARBOOCEAN. Started in September 2013 with a budget of 7 Million Euros over 4 years the project has 29 partners drawn from academia, research institutions and SME's. In addition 12 international experts from a wide range of disciplines comprise an Advisory Board. On behalf of the FixO3 Consortium, we present the programme that will be achieved through the activities of 12 Work Packages: 1. Coordination activities to integrate and harmonise the current procedures and processes. Strong links will be fostered with the wider community across academia, industry, policy and the general public through outreach, knowledge exchange and training. 2. Support actions to offer a) free access to observatory infrastructures to those who do not have such access, and b) free and open data services and products. 3. Joint research activities to innovate and enhance the current capability for multidisciplinary in situ ocean observation. Support actions include Transnational Access (TNA) to FixO3 infrastructure, meaning that European organizations can apply to free-of-charge access to the observatories for research and testing in two international calls during the project lifetime. The first call for TNA opens in summer 2014. More information can be found on FixO3 website (www.fixo3.eu/). Open ocean observation is currently a high priority for European marine and maritime activities. FixO3 will provide important data on environmental products and services to address the Marine Strategy

  20. Coal air turbine {open_quotes}CAT{close_quotes} program invention 604. Fourth quarter project report, July 1995--September 1995

    SciTech Connect

    Foster-Pegg, R.W.

    1995-10-31

    A coal air turbine `CAT` generates electric power and heat from coal combustion. The purpose of this project is the conceptual design of a `CAT` plant, and to make a comparison of the capital cost and and cost of power and steam from the `CAT` plant with power produced by alternate plants at the same site. Three configurations investigated include: condensing plant utilizing coal fuel and a condenser tower, or river, for cooling; a cogeneration plant utilizing coal and a steam turbine; and a cogeneration plant utilizing steam export and injection with waste coal fuel.

  1. Characterisation and airborne deployment of a new counterflow virtual impactor inlet

    NASA Astrophysics Data System (ADS)

    Shingler, T.; Dey, S.; Sorooshian, A.; Brechtel, F. J.; Wang, Z.; Metcalf, A.; Coggon, M.; Mülmenstädt, J.; Russell, L. M.; Jonsson, H. H.; Seinfeld, J. H.

    2012-06-01

    A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterisation tests and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (i) negligible organic contamination; (ii) a significant sample flow rate to downstream instruments (∼15 l min-1) that reduces the need for dilution; and (iii) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterised the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7-13.1 μm. The mean percentage error between cut size measurements and predictions from aerodynamic drag theory is 1.7%. The CVI was deployed on the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California in July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream of the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter.

  2. Characterization and airborne deployment of a new counterflow virtual impactor inlet

    NASA Astrophysics Data System (ADS)

    Shingler, T.; Dey, S.; Sorooshian, A.; Brechtel, F. J.; Wang, Z.; Metcalf, A.; Coggon, M.; Mülmenstädt, J.; Russell, L. M.; Jonsson, H. H.; Seinfeld, J. H.

    2012-02-01

    A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterization tests, and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (i) negligible organic contamination; (ii) a significant sample flow rate to downstream instruments (~15 l min-1) that reduces the need for dilution; and (iii) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterized the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7-13.1 μm. The percentage error between cut size measurements and predictions from aerodynamic drag theory are less than 13%. The CVI was deployed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California between July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter.

  3. Mach 4 Performance of a Fixed-Geometry Hypersonic Inlet with Rectangular-to-Elliptical Shape Transition

    NASA Technical Reports Server (NTRS)

    Smart, Michael K.; Trexler, Carl A.

    2003-01-01

    Wind-tunnel testing of a hypersonic inlet with rectangular-to-elliptical shape transition has been conducted at Mach 4.0. These tests were performed to investigate the starting and back-pressure limits of this fixed-geometry inlet at conditions well below the Mach 5.7 design point. Results showed that the inlet required side spillage holes in order to self-start at Mach 4.0. Once started, the inlet generated a compression ratio of 12.6, captured almost 80% of available air and withstood a back-pressure ratio of 30.3 relative to tunnel static pressure. The spillage penalty for self-starting was estimated to be 4% of available air. These experimental results, along with previous experimental results at Mach 6.2 indicate that fixed-geometry inlets with rectangular-to-elliptical shape transition are a viable configuration for airframe-integrated scramjets that operate over a significant Mach number range. Nomenclature

  4. Investigation of REST-Class Hypersonic Inlet Designs

    NASA Technical Reports Server (NTRS)

    Gollan, Rowan; Ferlemann, Paul G.

    2011-01-01

    Rectangular-to-elliptical shape-transition (REST) inlets are of interest for use on scramjet engines because they are efficient and integrate well with the forebody of a planar vehicle. The classic design technique by Smart for these inlets produces an efficient inlet but the complex three-dimensional viscous effects are only approximately included. Certain undesirable viscous features often occur in these inlets. In the present work, a design toolset has been developed which allows for rapid design of REST-class inlet geometries and the subsequent Navier-Stokes analysis of the inlet performance. This gives the designer feedback on the complex viscous effects at each design iteration. This new tool is applied to design an inlet for on-design operation at Mach 8. The tool allows for rapid investigation of design features that was previously not possible. The outcome is that the inlet shape can be modified to affect aspects of the flow field in a positive way. In one particular example, the boundary layer build-up on the bodyside of the inlet was reduced by 20% of the thickness associated with the classically designed inlet shape.

  5. Characterization of bacterial and archaeal communities in air-cathode microbial fuel cells, open circuit and sealed-off reactors.

    PubMed

    Shehab, Noura; Li, Dong; Amy, Gary L; Logan, Bruce E; Saikaly, Pascal E

    2013-11-01

    A large percentage of organic fuel consumed in a microbial fuel cell (MFC) is lost as a result of oxygen transfer through the cathode. In order to understand how this oxygen transfer affects the microbial community structure, reactors were operated in duplicate using three configurations: closed circuit (CC; with current generation), open circuit (OC; no current generation), and sealed off cathodes (SO; no current, with a solid plate placed across the cathode). Most (98 %) of the chemical oxygen demand (COD) was removed during power production in the CC reactor (maximum of 640 ± 10 mW/m(2)), with a low percent of substrate converted to current (coulombic efficiency of 26.5 ± 2.1 %). Sealing the cathode reduced COD removal to 7 %, but with an open cathode, there was nearly as much COD removal by the OC reactor (94.5 %) as the CC reactor. Oxygen transfer into the reactor substantially affected the composition of the microbial communities. Based on analysis of the biofilms using 16S rRNA gene pyrosequencing, microbes most similar to Geobacter were predominant on the anodes in the CC MFC (72 % of sequences), but the most abundant bacteria were Azoarcus (42 to 47 %) in the OC reactor, and Dechloromonas (17 %) in the SO reactor. Hydrogenotrophic methanogens were most predominant, with sequences most similar to Methanobacterium in the CC and SO reactor, and Methanocorpusculum in the OC reactors. These results show that oxygen leakage through the cathode substantially alters the bacterial anode communities, and that hydrogenotrophic methanogens predominate despite high concentrations of acetate. The predominant methanogens in the CC reactor most closely resembled those in the SO reactor, demonstrating that oxygen leakage alters methanogenic as well as general bacterial communities.

  6. Photogrammetry Driven Tools to Support the Restoration of Open-Air Bronze Surfaces of Sculptures: AN Integrated Solution Starting from the Experience of the Neptune Fountain in Bologna

    NASA Astrophysics Data System (ADS)

    Apollonio, F. I.; Gaiani, M.; Basilissi, W.; Rivaroli, L.

    2017-02-01

    Checking the irreversible process of clean-up is a delicate task that requires a work of synthesis between theoretical knowledge and practical experience, to define an effective operating protocol on a limited patch area to be extended later to the entire artefact's surface. In this paper, we present a new, quick, semi-automated 3D photogrammetry-based solution to support restorers in the open-air bronze artwork cleaning from corrosion and weathering decay. The solution allows the conservators to assess in real time and with a high level of fidelity in colour and shape, the `surfaces' to be cleaned before, during and after the clear-out treatment. The solution besides allows an effective and valuable support tool for restorers to identify the original layer of the bronze surface, developed and validated during the ongoing restoration of the Neptune Fountain in Bologna.

  7. Characteristic of the Nanoparticles Formed on the Carbon Steel Surface Contacting with 3d-Metal Water Salt Solutions in the Open-Air System.

    PubMed

    Lavrynenko, O M; Pavlenko, O Yu; Shchukin, Yu S

    2016-12-01

    The contact of a steel electrode with water dispersion medium in an open-air system leads to the development of various polymorphic iron oxides and oxyhydroxides on the steel surface. Whereas the usage of distilled water causes the obtaining of Fe(II)-Fe(III) layered double hydroxides (green rust) as a primary mineral phase, but in the presence of inorganic 3d-metal water salt solutions, mixed layered double hydroxides (LDHs) together with non-stoichiometric spinel ferrite nanoparticles are formed on the steel surface. Mixed LDHs keep stability against further oxidation and complicate the obtaining of spinel ferrite nanoparticles. Thermal treatment of mixed LDHs among other mineral phases formed via the rotation-corrosion dispergation process at certain temperatures permits to obtain homogenous nanoparticles of spinel ferrites as well as maghemite or hematite doped by 3d-metal cations.

  8. Uniform, stable, and efficient planar-heterojunction perovskite solar cells by facile low-pressure chemical vapor deposition under fully open-air conditions.

    PubMed

    Luo, Paifeng; Liu, Zhaofan; Xia, Wei; Yuan, Chenchen; Cheng, Jigui; Lu, Yingwei

    2015-02-04

    Recently, hybrid perovskite solar cells (PSCs) have attracted extensive attention due to their high efficiency and simple preparing process. Herein, a facile low-pressure chemical vapor deposition (LPCVD) technology is first developed to fabricate PSCs, which can effectively reduce the over-rapid intercalating reaction rate and easily overcome this blocking issue during the solution process. As a result, the prepared uniform perovskite films exhibit good crystallization, strong absorption, and long carrier diffusion length. More strikingly, CH3NH3PbI3 absorbers by LPCVD demonstrate excellent moisture-resistant feature even under laser illumination and high-temperature conditions, which indicates that our proprietary method is very suitable for the future low-cost, nonvacuum production of the new generation photovoltaic devices. Finally, high efficiency of 12.73% is successfully achieved under fully open-air conditions. To the best of our knowledge, this is the first report of efficient PSCs with such a high humidity above 60%.

  9. Characteristic of the Nanoparticles Formed on the Carbon Steel Surface Contacting with 3d-Metal Water Salt Solutions in the Open-Air System

    NASA Astrophysics Data System (ADS)

    Lavrynenko, O. M.; Pavlenko, O. Yu; Shchukin, Yu S.

    2016-02-01

    The contact of a steel electrode with water dispersion medium in an open-air system leads to the development of various polymorphic iron oxides and oxyhydroxides on the steel surface. Whereas the usage of distilled water causes the obtaining of Fe(II)-Fe(III) layered double hydroxides (green rust) as a primary mineral phase, but in the presence of inorganic 3d-metal water salt solutions, mixed layered double hydroxides (LDHs) together with non-stoichiometric spinel ferrite nanoparticles are formed on the steel surface. Mixed LDHs keep stability against further oxidation and complicate the obtaining of spinel ferrite nanoparticles. Thermal treatment of mixed LDHs among other mineral phases formed via the rotation-corrosion dispergation process at certain temperatures permits to obtain homogenous nanoparticles of spinel ferrites as well as maghemite or hematite doped by 3d-metal cations.

  10. Air velocity distributions inside tree canopies from a variable-rate air-assisted sprayer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variable-rate, air assisted, five-port sprayer had been in development to achieve variable discharge rates of both liquid and air. To verify the variable air rate capability by changing the fan inlet diameter of the sprayer, air jet velocities impeded by plant canopies were measured at various loc...

  11. Computational study of inlet injection for a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine

    NASA Technical Reports Server (NTRS)

    Gonzalez, D. E.

    1995-01-01

    A computational simulation of reacting 2-D and 3-D flowfields in a model inlet section of a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine concept was performed. LARCK, a multi-dimensional Navier-Stokes code with finite-rate kinetics chemistry developed at NASA LaRC by J.A. White, was adapted for this simulation. The flow conditions in the simulation match those envisioned for the PM/SIC engine experiments currently planned at LaRC. The reacting flowfields were Mach 6.3 freestream air and Mach 2 hydrogen at various pressure and temperature conditions injected through a slot injector at the base of the inlet section. In the PM/SIC engine, fuel is injected at the inlet section upstream of the combustor, and reaction is initiated by the shock wave at the inlet which increases the gas temperature and pressure beyond the kinetic limits for reaction. Many challenges exist prior to establishing shock-controlled combustion as a practical engine concept. These challenges include fuel injection schemes that can provide proper fuel-air mixing without creating large losses in the inlet section, and control of the combustion process so that early ignition or combustion propagation through the inlet boundary layer does not occur. For this project, a parametrics study was carried out to model the fuel injection of hydrogen at different flow conditions. It was found that, as the fuel temperature and pressure were increased, the potential for pre-ignition was high at a short distance downstream of the slot injector. The next stage of this work will investigate injection techniques for enhancing mixing of fuel and air in a manner that prevents or reduces the potential for premature ignition observed numerically.

  12. Geomorphic Analysis of Mattituck Inlet and Goldsmith Inlet, Long Island, New York

    DTIC Science & Technology

    2005-07-01

    Militello et al. (2000). c. Site-specific inlet studies: Gofseyeff (1952), Czerniak (1977), Schmeltz et al. (1982), Militello and Kraus (2001), Kraus et al...New York, 11952-9500. Czerniak , M. T. (1977). "Ilet interaction and stability theory verification," Proceedings Coastal Sediments 󈨑, ASCE, 754-773

  13. Localization and imaging of gangliosides in mouse brain tissue sections by laserspray ionization inlet[S

    PubMed Central

    Richards, Alicia L.; Lietz, Christopher B.; Wager-Miller, James; Mackie, Ken; Trimpin, Sarah

    2012-01-01

    A new ionization method for the analysis of fragile gangliosides without undesired fragmentation or salt adduction is presented. In laserspray ionization inlet (LSII), the matrix/analyte sample is ablated at atmospheric pressure, and ionization takes place in the ion transfer capillary of the mass spectrometer inlet by a process that is independent of a laser wavelength or voltage. The softness of LSII allows the identification of gangliosides up to GQ1 with negligible sialic acid loss. This is of importance to the field of MS imaging, as undesired fragmentation has made it difficult to accurately map the spatial distribution of fragile ganglioside lipids in tissue. Proof-of-principle structural characterization of endogenous gangliosides using MSn fragmentation of multiply charged negative ions on a LTQ Velos and subsequent imaging of the GD1 ganglioside is demonstrated. This is the first report of multiply charged negative ions using inlet ionization. We find that GD1 is detected at higher levels in the mouse cortex and hippocampus compared with the thalamus. In LSII with the laser aligned in transmission geometry relative to the inlet, images were obtained in approximately 60 min using an inexpensive nitrogen laser. PMID:22262808

  14. Influence of Inlet / Shoal Complex on Adjacent Shorelines via Inlet Sink Method

    DTIC Science & Technology

    2012-07-01

    placing dredged material onto adjacent beaches in moderate quantities (~200-500K cu yd) since the 1970 ’s (Dredging Information System (DIS...southward to Matanzas Inlet. Analysis of the ebb shoal volume change between surveys was made within a GIS framework using an area mask (Fig. 6

  15. Photosynthesis, productivity, and yield of maize are not affected by open-air elevation of CO2 concentration in the absence of drought.

    PubMed

    Leakey, Andrew D B; Uribelarrea, Martin; Ainsworth, Elizabeth A; Naidu, Shawna L; Rogers, Alistair; Ort, Donald R; Long, Stephen P

    2006-02-01

    While increasing temperatures and altered soil moisture arising from climate change in the next 50 years are projected to decrease yield of food crops, elevated CO2 concentration ([CO2]) is predicted to enhance yield and offset these detrimental factors. However, C4 photosynthesis is usually saturated at current [CO2] and theoretically should not be stimulated under elevated [CO2]. Nevertheless, some controlled environment studies have reported direct stimulation of C4 photosynthesis and productivity, as well as physiological acclimation, under elevated [CO2]. To test if these effects occur in the open air and within the Corn Belt, maize (Zea mays) was grown in ambient [CO2] (376 micromol mol(-1)) and elevated [CO2] (550 micromol mol(-1)) using Free-Air Concentration Enrichment technology. The 2004 season had ideal growing conditions in which the crop did not experience water stress. In the absence of water stress, growth at elevated [CO2] did not stimulate photosynthesis, biomass, or yield. Nor was there any CO2 effect on the activity of key photosynthetic enzymes, or metabolic markers of carbon and nitrogen status. Stomatal conductance was lower (-34%) and soil moisture was higher (up to 31%), consistent with reduced crop water use. The results provide unique field evidence that photosynthesis and production of maize may be unaffected by rising [CO2] in the absence of drought. This suggests that rising [CO2] may not provide the full dividend to North American maize production anticipated in projections of future global food supply.

  16. First day of an oil spill on the open sea: early mass transfers of hydrocarbons to air and water.

    PubMed

    Gros, Jonas; Nabi, Deedar; Würz, Birgit; Wick, Lukas Y; Brussaard, Corina P D; Huisman, Johannes; van der Meer, Jan R; Reddy, Christopher M; Arey, J Samuel

    2014-08-19

    During the first hours after release of petroleum at sea, crude oil hydrocarbons partition rapidly into air and water. However, limited information is available about very early evaporation and dissolution processes. We report on the composition of the oil slick during the first day after a permitted, unrestrained 4.3 m(3) oil release conducted on the North Sea. Rapid mass transfers of volatile and soluble hydrocarbons were observed, with >50% of ≤C17 hydrocarbons disappearing within 25 h from this oil slick of <10 km(2) area and <10 μm thickness. For oil sheen, >50% losses of ≤C16 hydrocarbons were observed after 1 h. We developed a mass transfer model to describe the evolution of oil slick chemical composition and water column hydrocarbon concentrations. The model was parametrized based on environmental conditions and hydrocarbon partitioning properties estimated from comprehensive two-dimensional gas chromatography (GC×GC) retention data. The model correctly predicted the observed fractionation of petroleum hydrocarbons in the oil slick resulting from evaporation and dissolution. This is the first report on the broad-spectrum compositional changes in oil during the first day of a spill at the sea surface. Expected outcomes under other environmental conditions are discussed, as well as comparisons to other models.

  17. On the importance of high-frequency air-temperature fluctuations for spectroscopic corrections of open-path carbon dioxide flux measurements

    NASA Astrophysics Data System (ADS)

    Bogoev, Ivan; Helbig, Manuel; Sonnentag, Oliver

    2015-04-01

    A growing number of studies report systematic differences in CO2 flux estimates obtained with the two main types of gas analyzers: compared to eddy-covariance systems based on closed-path (CP) gas analyzers, systems with open-path (OP) gas analyzers systematically overestimate CO2 uptake during daytime periods with high positive sensible heat fluxes, while patterns for differences in nighttime CO2 exchange are less obvious. These biases have been shown to correlate with the sign and the magnitude of the sensible heat flux and to introduce large uncertainties when calculating annual CO2 budgets. In general, CP and OP gas analyzers commonly used to measure the CO2 density in the atmosphere operate on the principle of infrared light absorption approximated by Beer-Lambert's law. Non-dispersive interference-based optical filter elements are used to select spectral bands with strong attenuation of light transmission, characteristic to the gas of interest. The intensity of the light passing through the optical sensing path depends primarily on the amount of absorber gas in the measurement volume. Besides the density of the gas, barometric pressure and air temperature are additional factors affecting the strength and the half-width of the absorption lines. These so-called spectroscopic effects are accounted for by measuring barometric pressure and air temperature in the sensing path and scaling the light-intensity measurements before applying the calibration equation. This approach works well for CP gas analyzers with an intake tube that acts as a low-pass filter on fast air-temperature fluctuations. Low-frequency response temperature sensors in the measurement cell are therefore sufficient to account for spectroscopic temperature effects. In contrast, OP gas analyzers are exposed to high-frequency air-temperature fluctuations associated with the atmospheric surface-layer turbulent heat exchange. If not corrected adequately, these fast air-temperature variations can cause

  18. A Robust Design Methodology for Optimal Microscale Secondary Flow Control in Compact Inlet Diffusers

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Keller, Dennis J.

    2001-01-01

    It is the purpose of this study to develop an economical Robust design methodology for microscale secondary flow control in compact inlet diffusers. To illustrate the potential of economical Robust Design methodology, two different mission strategies were considered for the subject inlet, namely Maximum Performance and Maximum HCF Life Expectancy. The Maximum Performance mission maximized total pressure recovery while the Maximum HCF Life Expectancy mission minimized the mean of the first five Fourier harmonic amplitudes, i.e., 'collectively' reduced all the harmonic 1/2 amplitudes of engine face distortion. Each of the mission strategies was subject to a low engine face distortion constraint, i.e., DC60<0.10, which is a level acceptable for commercial engines. For each of these missions strategies, an 'Optimal Robust' (open loop control) and an 'Optimal Adaptive' (closed loop control) installation was designed over a twenty degree angle-of-incidence range. The Optimal Robust installation used economical Robust Design methodology to arrive at a single design which operated over the entire angle-of-incident range (open loop control). The Optimal Adaptive installation optimized all the design parameters at each angle-of-incidence. Thus, the Optimal Adaptive installation would require a closed loop control system to sense a proper signal for each effector and modify that effector device, whether mechanical or fluidic, for optimal inlet performance. In general, the performance differences between the Optimal Adaptive and Optimal Robust installation designs were found to be marginal. This suggests, however, that Optimal Robust open loop installation designs can be very competitive with Optimal Adaptive close loop designs. Secondary flow control in inlets is inherently robust, provided it is optimally designed. Therefore, the new methodology presented in this paper, combined array 'Lower Order' approach to Robust DOE, offers the aerodynamicist a very viable and

  19. Method of making a small inlet optical panel

    DOEpatents

    Veligdan, James T.; Slobodin, David E.

    2004-02-03

    An optical panel having a small inlet, and a method of making a small inlet optical panel, are disclosed, which optical panel includes a individually coating, stacking, and cutting a first plurality of stacked optical waveguides to form an outlet face body with an outlet face, individually coating, stacking, and cutting a second plurality of stacked optical waveguides to form an inlet face body with an inlet face, and connecting an optical coupling element to the first plurality and second plurality of stacked optical waveguides, wherein the optical coupling element redirects light along a parallel axis of the inlet face to a parallel axis of the outlet face. In the preferred embodiment of the present invention, the inlet face is disposed obliquely with and askew from the outlet face.

  20. Zonal analysis of two high-speed inlets

    NASA Technical Reports Server (NTRS)

    Dilley, A. D.; Switzer, G. F.; Eppard, W. M.

    1991-01-01

    Using a zonal technique, thin layer Navier-Stokes solutions for two high speed inlet geometries are presented and compared with experimental data. The first configuration consists of a 3-D inlet preceded by a sharp flat plate. Results with two different grids demonstrate the importance of adequate grid refinement in high speed internal flow computations. The fine grid solution has reasonably good agreement with experimental heat transfer and pressure values inside the inlet. The other configuration consists of a 3-D inlet mounted on a research hypersonic forebody. Numerical results for this configuration have good agreement with experimental pressure data along the forebody, but not inside the inlet. A more refined grid calculation is currently being done to better predict the flowfield in the inlet.

  1. Boundary-layer-ingesting inlet flow control system

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R. (Inventor); Allan, Brian G. (Inventor)

    2010-01-01

    A system for reducing distortion at the aerodynamic interface plane of a boundary-layer-ingesting inlet using a combination of active and passive flow control devices is disclosed. Active flow control jets and vortex generating vanes are used in combination to reduce distortion across a range of inlet operating conditions. Together, the vortex generating vanes can reduce most of the inlet distortion and the active flow control jets can be used at a significantly reduced control jet mass flow rate to make sure the inlet distortion stays low as the inlet mass flow rate varies. Overall inlet distortion, measured and described as average SAE circumferential distortion descriptor, was maintained at a value of 0.02 or less. Advantageous arrangements and orientations of the active flow control jets and the vortex generating vanes were developed using computational fluid dynamics simulations and wind tunnel experimentations.

  2. Source fingerprint monitoring of air pollutants from petrochemical industry and the determination of their annual emission flux using open path Fourier transform infrared spectroscopy

    SciTech Connect

    Yih-Shiaw Huang; Shih-Yi Chang; Tai-Ly Tso

    1996-12-31

    Toxic air pollutants were investigated in several petrochemical industrial park in Taiwan using a movable open-path Fourier-transform infrared spectroscopy (FTIR). The results show the qualitative and quantitative analysis of emission gases from plants, and also provide the emission rates of various compounds. More than twenty compounds under usual operation were found from these industrial park. The concentration variation with time could be correlated exactly with the distances from the emission source along the wind direction. This means that by changing the measuring points the source of emission could be unambiguously identified. The point, area and line source (PAL) plume dispersion model has been applied to estimate the emission rate of either a point or an area source. The local atmospheric stability was determined by releasing an SF{sub 6} tracer. The origin of errors came mainly from the uncertainty of the source configuration and the variation of the meteorological condition. Through continuous measurement using a portable open-path Fourier transform infrared (POP-FTIR) spectrometer, the maximum value of the emission rate and the annual amount of emission could be derived. The emission rate of the measured toxic gases was derived by the model technique, and the results show that the emission amount is on the order of ten to hundred tons per year.

  3. Open-air-nesting honey bees Apis dorsata and Apis laboriosa differ from the cavity-nesting Apis mellifera and Apis cerana in brood hygiene behaviour.

    PubMed

    Woyke, J; Wilde, J; Reddy, C C

    2004-01-01

    The cavity-nesting Apis mellifera and Apis cerana bees detect, uncap, and remove diseased brood. The hygiene behaviour of open-air-nesting bees Apis dorsata and Apis laboriosa was investigated in India and Nepal. Sealed A. dorsata pupae were pin-killed or deep-frozen. The workers removed 73 or 37% of damaged pin-killed pupae depending on the diameter of the pins, and only 7% of the frozen undamaged pupae. Migrating A. dorsata and A. laboriosa left unopened the sealed brood in deserted combs. Thus, A. dorsata and A. laboriosa do not open undamaged cells with dead brood. This behaviour is a more efficient mechanism in preventing the spread of diseases and parasitic mites than uncapping and removing dead pupae by A. mellifera and A. cerana. It may be beneficial for migrating A. dorsata and A. laboriosa to temporarily disuse part of the comb cells in exchange for arresting the mites there and thus reducing the increase of their population.

  4. NASCRIN - NUMERICAL ANALYSIS OF SCRAMJET INLET

    NASA Technical Reports Server (NTRS)

    Kumar, A.

    1994-01-01

    The NASCRIN program was developed for analyzing two-dimensional flow fields in supersonic combustion ramjet (scramjet) inlets. NASCRIN solves the two-dimensional Euler or Navier-Stokes equations in conservative form by an unsplit, explicit, two-step finite-difference method. A more recent explicit-implicit, two-step scheme has also been incorporated in the code for viscous flow analysis. An algebraic, two-layer eddy-viscosity model is used for the turbulent flow calculations. NASCRIN can analyze both inviscid and viscous flows with no struts, one strut, or multiple struts embedded in the flow field. NASCRIN can be used in a quasi-three-dimensional sense for some scramjet inlets under certain simplifying assumptions. Although developed for supersonic internal flow, NASCRIN may be adapted to a variety of other flow problems. In particular, it should be readily adaptable to subsonic inflow with supersonic outflow, supersonic inflow with subsonic outflow, or fully subsonic flow. The NASCRIN program is available for batch execution on the CDC CYBER 203. The vectorized FORTRAN version was developed in 1983. NASCRIN has a central memory requirement of approximately 300K words for a grid size of about 3,000 points.

  5. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  6. Breathing zone air sampler

    SciTech Connect

    Tobin, J.

    1989-08-22

    A sampling apparatus is presented which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  7. A novel low-cost open-hardware platform for monitoring soil water content and multiple soil-air-vegetation parameters.

    PubMed

    Bitella, Giovanni; Rossi, Roberta; Bochicchio, Rocco; Perniola, Michele; Amato, Mariana

    2014-10-21

    Monitoring soil water content at high spatio-temporal resolution and coupled to other sensor data is crucial for applications oriented towards water sustainability in agriculture, such as precision irrigation or phenotyping root traits for drought tolerance. The cost of instrumentation, however, limits measurement frequency and number of sensors. The objective of this work was to design a low cost "open hardware" platform for multi-sensor measurements including water content at different depths, air and soil temperatures. The system is based on an open-source ARDUINO microcontroller-board, programmed in a simple integrated development environment (IDE). Low cost high-frequency dielectric probes were used in the platform and lab tested on three non-saline soils (ECe1: 2.5 < 0.1 mS/cm). Empirical calibration curves were subjected to cross-validation (leave-one-out method), and normalized root mean square error (NRMSE) were respectively 0.09 for the overall model, 0.09 for the sandy soil, 0.07 for the clay loam and 0.08 for the sandy loam. The overall model (pooled soil data) fitted the data very well (R2 = 0.89) showing a high stability, being able to generate very similar RMSEs during training and validation (RMSE(training) = 2.63; RMSE(validation) = 2.61). Data recorded on the card were automatically sent to a remote server allowing repeated field-data quality checks. This work provides a framework for the replication and upgrading of a customized low cost platform, consistent with the open source approach whereby sharing information on equipment design and software facilitates the adoption and continuous improvement of existing technologies.

  8. A Novel Low-Cost Open-Hardware Platform for Monitoring Soil Water Content and Multiple Soil-Air-Vegetation Parameters

    PubMed Central

    Bitella, Giovanni; Rossi, Roberta; Bochicchio, Rocco; Perniola, Michele; Amato, Mariana

    2014-01-01

    Monitoring soil water content at high spatio-temporal resolution and coupled to other sensor data is crucial for applications oriented towards water sustainability in agriculture, such as precision irrigation or phenotyping root traits for drought tolerance. The cost of instrumentation, however, limits measurement frequency and number of sensors. The objective of this work was to design a low cost “open hardware” platform for multi-sensor measurements including water content at different depths, air and soil temperatures. The system is based on an open-source ARDUINO microcontroller-board, programmed in a simple integrated development environment (IDE). Low cost high-frequency dielectric probes were used in the platform and lab tested on three non-saline soils (ECe1: 2.5 < 0.1 mS/cm). Empirical calibration curves were subjected to cross-validation (leave-one-out method), and normalized root mean square error (NRMSE) were respectively 0.09 for the overall model, 0.09 for the sandy soil, 0.07 for the clay loam and 0.08 for the sandy loam. The overall model (pooled soil data) fitted the data very well (R2 = 0.89) showing a high stability, being able to generate very similar RMSEs during training and validation (RMSEtraining = 2.63; RMSEvalidation = 2.61). Data recorded on the card were automatically sent to a remote server allowing repeated field-data quality checks. This work provides a framework for the replication and upgrading of a customized low cost platform, consistent with the open source approach whereby sharing information on equipment design and software facilitates the adoption and continuous improvement of existing technologies. PMID:25337742

  9. Investigation on inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet

    NASA Astrophysics Data System (ADS)

    Yang, Ce; Wang, Yingjun; Lao, Dazhong; Tong, Ding; Wei, Longyu; Liu, Yixiong

    2016-08-01

    The inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet structures were studied in numerical method, mainly focused on three issues including the amounts and differences of the inlet recirculation in different working conditions, the circumferential non-uniform distributions of the inlet recirculation, the recirculation velocity distributions of the upstream slot of the rear impeller. The results show that there are some differences between the recirculation of the front impeller and that of the rear impeller in whole working conditions. In design speed, the recirculation flow rate of the rear impeller is larger than that of the front impeller in the large flow range, but in the small flow range, the recirculation flow rate of the rear impeller is smaller than that of the front impeller. In different working conditions, the recirculation velocity distributions of the front and rear impeller are non-uniform along the circumferential direction and their non-uniform extents are quite different. The circumferential non-uniform extent of the recirculation velocity varies with the working conditions change. The circumferential non-uniform extent of the recirculation velocity of front impeller and its distribution are determined by the static pressure distribution of the front impeller, but that of the rear impeller is decided by the coupling effects of the inlet flow distortion of the rear impeller, the circumferential unsymmetrical distribution of the upstream slot and the asymmetric structure of the volute. In the design flow and small flow conditions, the recirculation velocities at different circumferential positions of the mean line of the upstream slot cross-section of the rear impeller are quite different, and the recirculation velocities distribution forms at both sides of the mean line are different. The recirculation velocity distributions in the cross-section of the upstream slot depend on the static pressure

  10. Evolution and Impacts of a New Inlet Formed in Fire Island National Park by Superstorm Sandy (Invited)

    NASA Astrophysics Data System (ADS)

    Flood, R. D.; Flagg, C. N.; Goff, J. A.; Austin, J. A.; Schwab, W. C.; Denny, J. F.; Christensen, B. A.; Browne, C. M.; Saustrup, S.

    2013-12-01

    Superstorm Sandy impacted the New York / New Jersey area on October 29, 2012 and brought a storm surge of 1.5 to 2.5 m and waves with a significant wave height of 9.5 m to the south shore of Long Island, New York. The storm cut three inlets across Fire Island barrier islands. Two of the inlets were closed mechanically, but the third inlet, cut through a wilderness area of the Fire Island National Seashore, remains open and provides a rare opportunity to study the evolution and dynamics of an unmanaged inlet. This new inlet formed where Fire Island is narrow and is near the site of an earlier inlet that closed in 1825. Great South Bay (GSB) is located between Fire Island and the Long Island mainland. The salinity in GSB increased by 5 salinity units following the breach and has remained high. GSB has had chronic water quality issues associated with a high population density that may be moderated by flow related to the new inlet. Water flow through the new inlet is controlled by the difference between offshore tide and GSB tide, but GSB tide does not appear to have been altered by flow through the inlet. This is different from the traditional view of inlet dynamics where a balance is sought between channel cross-sectional area, tidal prism (which together give channel velocity) and longshore sediment transport. At SoMAS we have been monitoring the evolution of the new inlet since its formation. We have conducted overflights at 1 to 3 week intervals to track the changing inlet geometry and the location of flood-tidal and ebb-tidal deltas. We have also done small-boat bathymetric surveys of the channel itself every 3 to 5 weeks to track the shape and cross-sectional area of the channel. The channel was quite small shortly after the breach with a depth of about 2 m. The channel grew fast as it cut into underlying fine-grain sediments, reaching a depth of over 6 m following several late winter storms. The inlet channel initially migrated quickly to the west, but its

  11. Inlet Development for a Rocket Based Combined Cycle, Single Stage to Orbit Vehicle Using Computational Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Trefny, C. J.; Steffen, C. J., Jr.

    1999-01-01

    Design and analysis of the inlet for a rocket based combined cycle engine is discussed. Computational fluid dynamics was used in both the design and subsequent analysis. Reynolds averaged Navier-Stokes simulations were performed using both perfect gas and real gas assumptions. An inlet design that operates over the required Mach number range from 0 to 12 was produced. Performance data for cycle analysis was post processed using a stream thrust averaging technique. A detailed performance database for cycle analysis is presented. The effect ot vehicle forebody compression on air capture is also examined.

  12. Experimental and numerical analyses of finned cross flow heat exchangers efficiency under non-uniform gas inlet flow conditions

    NASA Astrophysics Data System (ADS)

    Bury, Tomasz; Składzień, Jan; Widziewicz, Katarzyna

    2010-10-01

    The work deals with experimental and numerical thermodynamic analyses of cross-flow finned tube heat exchangers of the gas-liquid type. The aim of the work is to determine an impact of the gas non-uniform inlet on the heat exchangers performance. The measurements have been carried out on a special testing rig and own numerical code has been used for numerical simulations. Analysis of the experimental and numerical results has shown that the range of the non-uniform air inlet to the considered heat exchangers may be significant and it can significantly affect the heat exchanger efficiency.

  13. Survey of inlet noise reduction concepts for gas turbine engines

    NASA Technical Reports Server (NTRS)

    Lansing, D. L.; Chestnutt, D.

    1976-01-01

    An overview is given of advanced concepts for the suppression of noise in the inlets of gas turbine engines. Inlet geometric and operating parameters are presented and design criteria for suppression methods are discussed. Noise suppression concepts are described, the directions of current research are reviewed. Problem areas requiring further work are indicated. Well established approaches to inlet noise reduction - namely, acoustic liners and high subsonic Mach number inlets which are the focus of considerable current research activity are considered along with the acoustic absorption and watet vapor injection.

  14. SUPIN: A Computational Tool for Supersonic Inlet Design

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    2016-01-01

    A computational tool named SUPIN is being developed to design and analyze the aerodynamic performance of supersonic inlets. The inlet types available include the axisymmetric pitot, three-dimensional pitot, axisymmetric outward-turning, two-dimensional single-duct, two-dimensional bifurcated-duct, and streamline-traced inlets. The aerodynamic performance is characterized by the flow rates, total pressure recovery, and drag. The inlet flow-field is divided into parts to provide a framework for the geometry and aerodynamic modeling. Each part of the inlet is defined in terms of geometric factors. The low-fidelity aerodynamic analysis and design methods are based on analytic, empirical, and numerical methods which provide for quick design and analysis. SUPIN provides inlet geometry in the form of coordinates, surface angles, and cross-sectional areas. SUPIN can generate inlet surface grids and three-dimensional, structured volume grids for use with higher-fidelity computational fluid dynamics (CFD) analysis. Capabilities highlighted in this paper include the design and analysis of streamline-traced external-compression inlets, modeling of porous bleed, and the design and analysis of mixed-compression inlets. CFD analyses are used to verify the SUPIN results.

  15. CFD Models of a Serpentine Inlet, Fan, and Nozzle

    NASA Technical Reports Server (NTRS)

    Chima, R. V.; Arend, D. J.; Castner, R. S.; Slater, J. W.; Truax, P. P.

    2010-01-01

    Several computational fluid dynamics (CFD) codes were used to analyze the Versatile Integrated Inlet Propulsion Aerodynamics Rig (VIIPAR) located at NASA Glenn Research Center. The rig consists of a serpentine inlet, a rake assembly, inlet guide vanes, a 12-in. diameter tip-turbine driven fan stage, exit rakes or probes, and an exhaust nozzle with a translating centerbody. The analyses were done to develop computational capabilities for modeling inlet/fan interaction and to help interpret experimental data. Three-dimensional Reynolds averaged Navier-Stokes (RANS) calculations of the fan stage were used to predict the operating line of the stage, the effects of leakage from the turbine stream, and the effects of inlet guide vane (IGV) setting angle. Coupled axisymmetric calculations of a bellmouth, fan, and nozzle were used to develop techniques for coupling codes together and to investigate possible effects of the nozzle on the fan. RANS calculations of the serpentine inlet were coupled to Euler calculations of the fan to investigate the complete inlet/fan system. Computed wall static pressures along the inlet centerline agreed reasonably well with experimental data but computed total pressures at the aerodynamic interface plane (AIP) showed significant differences from the data. Inlet distortion was shown to reduce the fan corrected flow and pressure ratio, and was not completely eliminated by passage through the fan

  16. Blended Wing Body Systems Studies: Boundary Layer Ingestion Inlets With Active Flow Control

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A. (Technical Monitor); Daggett, David L.; Kawai, Ron; Friedman, Doug

    2003-01-01

    A CFD analysis was performed on a Blended Wing Body (BWB) aircraft with advanced, turbofan engines analyzing various inlet configurations atop the aft end of the aircraft. The results are presented showing that the optimal design for best aircraft fuel efficiency would be a configuration with a partially buried engine, short offset diffuser using active flow control, and a D-shaped inlet duct that partially ingests the boundary layer air in flight. The CFD models showed that if active flow control technology can be satisfactorily developed, it might be able to control the inlet flow distortion to the engine fan face and reduce the powerplant performance losses to an acceptable level. The weight and surface area drag benefits of a partially submerged engine shows that it might offset the penalties of ingesting the low energy boundary layer air. The combined airplane performance of such a design might deliver approximately 5.5% better aircraft fuel efficiency over a conventionally designed, pod-mounted engine.

  17. Basic research in fan source noise: Inlet distortion and turbulence noise

    NASA Technical Reports Server (NTRS)

    Kantola, R. A.; Warren, R. E.

    1978-01-01

    A widely recognized problem in jet engine fan noise is the discrepancy between inflight and static tests. This discrepancy consists of blade passing frequency tones, caused by ingested turbulence that appear in the static tests but not in flight. To reduce the ingested distortions and turbulence in an anechoic chamber, a reverse cone inlet is used to guide the air into the fan. This inlet also has provisions for boundary layer suction and is used in conjunction with a turbulence control structure (TCS) to condition the air impinging on the fan. The program was very successful in reducing the ingested turbulence, to the point where reductions in the acoustic power at blade passing frequency are as high as 18 db for subsonic tip speeds. Even with this large subsonic tone suppression, the supersonic tip speed tonal content remains largely unchanged, indicating that the TCS did not appreciably attenuate the noise but effects the generation via turbulence reduction. Turbulence mapping of the inlet confirmed that the tone reductions are due to a reduction in turbulence, as the low frequency power spectra of the streamwise and transverse turbulence were reduced by up to ten times and 100 times, respectively.

  18. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet-pressure data were obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top-mounted twin inlets. Data are presented from wind tunnel tests conducted at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27-deg and angles of sideslip up to 12-deg. Trimmed aerodynamic characteristics and inlet performance were compared for three different leading-edge extension (LEX) configurations. The effects of wing leading- and trailing-edge flaps on the inlet were also determined. Maneuver performance was calculated from combined force and inlet-pressure data. The largest of the three LEX sizes tested gave the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  19. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet pressure data are obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top mounted twin inlets. Data are presented from tests conducted in the Ames Unitary Wind Tunnels at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27 deg. and angles of sideslip up to 12 deg. Trimmed aerodynamic characteristics and inlet performance are compared for three different leading edge extension (LEX) configurations. The effects of wing leading and trailing-edge flaps on the inlet are also determined. Maneuver perfromance is calculated form combined force and inlet pressure data. The largest of the three LEX sizes tested gives the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  20. Preliminary Results of the Determination of Inlet-Pressure Distortion Effects on Compressor Stall and Altitude Operating Limits of the J57-P-1 Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Wallner, L. E.; Lubick, R. J.; Chelko, L. J.

    1955-01-01

    During an investigation of the J57-P-1 turbojet engine in the Lewis altitude wind tunnel, effects of inlet-flow distortion on engine stall characteristics and operating limits were determined. In addition to a uniform inlet-flow profile, the inlet-pressure distortions imposed included two radial, two circumferential, and one combined radial-circumferential profile. Data were obtained over a range of compressor speeds at an altitude of 50,000 and a flight Mach number of 0.8; in addition, the high- and low-speed engine operating limits were investigated up to the maximum operable altitude. The effect of changing the compressor bleed position on the stall and operating limits was determined for one of the inlet distortions. The circumferential distortions lowered the compressor stall pressure ratios; this resulted in less fuel-flow margin between steady-state operation and compressor stall. Consequently, the altitude operating Limits with circumferential distortions were reduced compared with the uniform inlet profile. Radial inlet-pressure distortions increased the pressure ratio required for compressor stall over that obtained with uniform inlet flow; this resulted in higher altitude operating limits. Likewise, the stall-limit fuel flows required with the radial inlet-pressure distortions were considerably higher than those obtained with the uniform inlet-pressure profile. A combined radial-circumferential inlet distortion had effects on the engine similar to the circumferential distortion. Bleeding air between the two compressors eliminated the low-speed stall limit and thus permitted higher altitude operation than was possible without compressor bleed.

  1. Experimental study on heat transfer performance of aluminium foam parallel-flow condenser in air conditioner

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Wan, Z. M.; Chang, H. W.; Wang, Y. D.

    2017-01-01

    Open cell aluminium foam was used in parallel-flow condenser in air conditioner, and two condensers with different pore density were fabricated. The experimental study was conducted on the heat transfer performance and temperature distribution. The experimental results show that both of the heat transfer load and air pressure drop increase with the increase of pore density, air velocity is 2.5m/s, the heat transfer capacities of the condenser with 10PPI and 8PPI are 4.786kw and 3.344kW respectively. Along the flow direction of refrigerant, the outlet temperatures of refrigerant drop with the rise of air velocity when the inlet temperature is constant. The outlet temperature of the refrigerant decreases with the increase of pore density.

  2. The design of an air-cooled metallic high temperature radial turbine

    NASA Technical Reports Server (NTRS)

    Snyder, Philip H.; Roelke, Richard J.

    1988-01-01

    Recent trends in small advanced gas turbine engines call for higher turbine inlet temperatures. Advances in radial turbine technology have opened the way for a cooled metallic radial turbine capable of withstanding turbine inlet temperatures of 2500 F while meeting the challenge of high efficiency in this small flow size range. In response to this need, a small air-cooled radial turbine has been designed utilizing internal blade coolant passages. The coolant flow passage design is uniquely tailored to simultaneously meet rotor cooling needs and rotor fabrication constraints. The rotor flow-path design seeks to realize improved aerodynamic blade loading characteristics and high efficiency while satisfying rotor life requirements. An up-scaled version of the final engine rotor is currently under fabrication and, after instrumentation, will be tested in the warm turbine test facility at the NASA Lewis Research Center.

  3. Tangential blowing for control of strong normal shock - Boundary layer interactions on inlet ramps

    NASA Technical Reports Server (NTRS)

    Schwendemann, M. F.; Sanders, B. W.

    1982-01-01

    The use of tangential blowing from a row of holes in an aft facing step is found to provide good control of the ramp boundary layer, normal shock interaction on a fixed geometry inlet over a wide range of inlet mass flow ratios. Ramp Mach numbers of 1.36 and 1.96 are investigated. The blowing geometry is found to have a significant effect on system performance at the highest Mach number. The use of high-temperature air in the blowing system, however, has only a slight effect on performance. The required blowing rates are significantly high for the most severe test conditions. In addition, the required blowing coefficient is found to be proportional to the normal shock pressure rise.

  4. Air turbo-ramjet engine

    SciTech Connect

    Kepler, C.E.

    1991-12-24

    This patent describes a jet engine capable of being used to power an aircraft throughout a range of speeds from subsonic to high supersonic. It comprises means for bounding an internal passage centered on an axis and including, in succession as considered in the direction of axial flow of incoming air into and through the passage, a fixed-area air inlet section, a diverging passage section, a mixing section, a combustion section, and an outlet section; fan means situated in the air inlet section and including a rotor mounted in the bounding means for rotation about the axis and including a plurality of circumferentially spaced rotor blade members; means for selectively rotating the rotor about the axis with attendant impelling action of the rotor blade members on the air flowing therebetween; and means for selectively discharging air from a region of the passage situated between the air inlet section and the diverging passage section to the exterior of the bounding means, both at subsonic and supersonic speeds of the aircraft, when the amount of incoming air passing through the fixed-area inlet section exceeds that required in the combustion section.

  5. Inlet-engine matching for SCAR including application of a bicone variable geometry inlet. [Supersonic Cruise Aircraft Research

    NASA Technical Reports Server (NTRS)

    Wasserbauer, J. F.; Gerstenmaier, W. H.

    1978-01-01

    Airflow characteristics of variable cycle engines (VCE) designed for Mach 2.32 can have transonic airflow requirements as high as 1.6 times the cruise airflow. This is a formidable requirement for conventional, high performance, axisymmetric, translating centerbody mixed compression inlets. An alternate inlet is defined where the second cone of a two cone centerbody collapses to the initial cone angle to provide a large off-design airflow capability, and incorporates modest centerbody translation to minimize spillage drag. Estimates of transonic spillage drag are competitive with those of conventional translating centerbody inlets. The inlet's cruise performance exhibits very low bleed requirements with good recovery and high angle of attack capability.

  6. Effectiveness of a serpentine inlet duct flow control scheme at design and off-design simulated flight conditions

    NASA Astrophysics Data System (ADS)

    Rabe, Angela C.

    An experimental investigation was conducted in a static ground test facility to determine the flow quality of a serpentine inlet duct incorporating active flow control for several simulated flight conditions. The total pressure distortion at the aerodynamic interface plane (AIP) was then used to predict the resulting stability for a compression system. This study was conducted using a model of a compact, low observable, engine inlet duct developed by Lockheed Martin. A flow control technique using air injection through microjets at 1% of the inlet mass flow rate was developed by Lockheed Martin to improve the quality of the flow exiting the inlet duct. Both the inlet duct and the flow control technique were examined at cruise condition and off-design simulated flight conditions (angle of attack and asymmetric distortion). All of the experimental tests were run at an inlet throat Mach number of 0.55 and a resulting Reynolds number of 1.76*105 based on the hydraulic diameter at the inlet throat. For each of the flight conditions tested, the flow control scheme was found to improve the flow uniformity and reduce the inlet distortion at the AIP. For simulated cruise condition, the total pressure recovery was improved by ˜2% with the addition of flow control. For the off-design conditions of angle of attack and asymmetric distortion, the total pressure recovery was improved by 1.5% and 2% respectively. All flight conditions tested showed a reduction in circumferential distortion intensity with flow control. The cruise condition case showed reduced maximum circumferential distortion of 70% with the addition of flow control. A reduction in maximum circumferential distortion of 40% occurred for the angle of attack case with flow control, and 30% for the asymmetric distortion case with flow control. The inlet total pressure distortion was used to predict the changes in stability margin of a compression system due to design and off-design flight conditions and the

  7. Bleed-boundary conditions for numerically simulated mixed-compression supersonic inlet flow

    NASA Technical Reports Server (NTRS)

    Chyu, W. J.; Howe, G. W.; Shih, T. I-P.

    1992-01-01

    A numerical study was performed to investigate boundary conditions for bleed openings that are needed in the numerical simulation of critical flow through turbojet inlets with bleed. Nine different boundary conditions (BCs) were devised and examined. Of the BCs examined, three were able to stabilize the terminal shock near the inlet's throat. This numerical study was based on the ensemble-averaged, unsteady, three-dimensional, compressible Navier-Stokes equations closed by the Baldwin-Lomax algebraic turbulence model. Solutions to the Navier-Stokes equations were obtained by using a hybrid implicit-explicit method (Beam and Warming/MacCormack). The multiblock grid system used in the solution procedure was generated by solving a set of elliptic partial differential equations. Solutions obtained were compared with available experimental data.

  8. Electromagnetic fields backscattered from an s-shaped inlet cavity with an absorber coating on its inner walls

    NASA Technical Reports Server (NTRS)

    Burkholder, R. J.; Chuang, C. W.; Pathak, P. H.

    1987-01-01

    The EM backscatter from a two-dimensional S-shaped inlet cavity is analyzed using three different techniques, namely a hybrid combination of asymptotic high frequency and modal methods, an integral equation method, and the geometrical optics ray method, respectively. This inlet has a thin absorber coating on its perfectly conducting inner walls and the planar interior termination is made perfectly conducting. The effect of the absorber on the inner wall is treated via a perturbation scheme in the hybrid approach where it is assumed that the loss is sufficiently small for the method to be valid. The results are compared with the backscatter from a straight inlet cavity to evaluate the effect of offsetting the termination in the S-bend configuration such that it is not visible from the open end of the inlet. The envelope of the backscatter pattern for the straight inlet is always seen to peak around the forward axis due to the large return from the directly visible termination, and the pattern envelope tapers off away from the forward axis. Offsetting the termination causes the envelope of the backscatter pattern to flatten out, thereby reducing the return near the forward axis by several dB. The absorber coating reduces the pattern level of the straight inlet in directions away from the forward axis but has little effect on the peak near the axis; furthermore, the absorber coating is seen to consistently reduce the backscatter from the S-bend inlet for almost all incidence angles. The hybrid method gives excellent agreement with experimental data and with the integral equation solution, whereas, the geometrical optics ray tracing method is able to generally predict the average of the bachscatter pattern but not the pattern details.

  9. Model aerodynamic test results for a refined actuated inlet ejector nozzle at simulated takeoff and cruise conditions

    NASA Technical Reports Server (NTRS)

    Nelson, D. P.

    1983-01-01

    Wind tunnel model tests were conducted to demonstrate the aerodynamic performance improvements of a refined actuated inlet ejector nozzle. Models of approximately one-tenth scale were configured to simulate nozzle operation at takeoff, subsonic cruise, transonic cruise and supersonic cruise. Variations of model components provided a performance evaluation of ejector inlet and exit area, forebody boattail angle and ejector inlet operation in the open and closed mode. Approximately 700 data points were acquired at Mach numbers of 0, 0.36, 0.9, 1.2, and 2.0 for a wide range of nozzle flow conditions. Results show that relative to two ejector nozzles previously tested performance was improved significantly at takeoff and subsonic cruise performance, a C sub f of 0.982, was attained equal to the high performance of the previous tests. The established advanced supersonic transport propulsion study performance goals were met or closely approached at takeoff and supersonic cruise.

  10. Air shooting system for the mining of coal or the like

    SciTech Connect

    Fitzgerald, J.E.

    1981-11-24

    An air shooting system is disclosed for use in lieu of explosives in the mining of coal employing a set of tubular shooting heads fitted in respective shot holes in a coal seam. Each shooting head is fed with air under high pressure and has a valve mechanism for triggering discharge of the air when it reaches a predetermined pressure. The source of air pressure is connected to a manifold and automatic shut-off valves are interposed between the manifold and the lines feeding the individual shooting heads. Each shutoff valve has a movable valve element biased into a normally open position to permit flow of air from inlet to outlet but which is snapped into closed position and held there by the inlet pressure when there is a sudden drop in pressure at the outlet accompanying discharge at the associated shooting head. The shooting heads are set to trigger in series at incrementally spaced pressures until all of the shut-off valves are in closed condition. A manual reset valve interposed between the source and the manifold cuts all flow from the source for resetting of the shut-off valves and prompt simultaneous venting of the lines feeding the shooting heads in readiness for a successive shot.

  11. Curved centerline air intake for a gas turbine engine

    NASA Technical Reports Server (NTRS)

    Ruehr, W. C.; Younghans, J. L.; Smith, E. B. (Inventor)

    1980-01-01

    An inlet for a gas turbine engine was disposed about a curved centerline for the purpose of accepting intake air that is flowing at an angle to engine centerline and progressively turning that intake airflow along a curved path into alignment with the engine. This curved inlet is intended for use in under the wing locations and similar regions where airflow direction is altered by aerodynamic characteristics of the airplane. By curving the inlet, aerodynamic loss and acoustic generation and emission are decreased.

  12. Smart actuation of inlet guide vanes for small turbine engine

    NASA Astrophysics Data System (ADS)

    Rusovici, Razvan; Kwok Choon, Stephen T.; Sepri, Paavo; Feys, Joshuo

    2011-04-01

    Unmanned Aerial Vehicles (UAVs) have gained popularity over the past few years to become an indispensable part of aerial missions that include reconnaissance, surveillance, and communication [1]. As a result, advancements in small jet-engine performance are needed to increase the performance (range, payload and efficiency) of the UAV. These jet engines designed especially for UAV's are characterized by thrust force on the order of 100N and due to their size and weight limitations, may lack advanced flow control devices such as IGV [2]. The goal of the current study was to present a conceptual design of an IGV smart-material based actuation mechanism that would be simple, compact and lightweight. The compressor section of an engine increases the pressure and conditions the flow before the air enters the combustion chamber [3]. The airflow entering the compressor is often turbulent due to the high angle of incidence between engine inlet and free-stream velocity, or existing atmospheric turbulence. Actuated IGV are used to help control the relative angle of incidence of the flow that enters the engine compressor, thereby preventing flow separation, compressor stall and thus extending the compressor's operating envelope [4]. Turbine jet- engines which employ variable IGV were developed by Rolls Royce (Trent DR-900) and General Electric (J79).

  13. Evaluation of physiological and biochemical responses of two rice (Oryza sativa L.) cultivars to ambient air pollution using open top chambers at a rural site in India.

    PubMed

    Rai, Richa; Agrawal, Madhoolika

    2008-12-15

    Air pollutant concentrations are rising in India, causing potential threats to crop production. As air pollutants are known to interfere with physiological processes, this study was conducted to assess the relative responses of physiological and biochemical characteristics of two cultivars of rice (Oryza sativa L. cv. Saurabh 950 and NDR 97) leading to variable yield responses. Twelve hour monitoring of ambient concentrations of SO2, NO2 and O3 in filtered chambers (FCs), non-filtered chambers (NFCs) and open plots (OPs) showed that O3 was the main pollutant at the experimental site. Ozone concentrations often exceeded 40 ppb during anthesis but not during the vegetative growth period. Photosynthetic rate (Ps), stomatal conductance (g(s)) and Fv/Fm ratio, superoxide dismutase (SOD) and peroxidase (POD) activities and photosynthetic pigments, ascorbic acid, total phenolics and protein contents were assessed at different developmental stages and yield of grains were quantified. Lipid peroxidation, SOD and POD activities, ascorbic acid and total phenolics were higher, whereas Ps, g(s), Fv/Fm ratio and contents of protein and photosynthetic pigment were lower in plants of NFCs as compared to FCs. Yield decreased significantly in both cultivars grown in NFCs. NDR 97 showed less reductions in physiological characteristics, photosynthetic pigments and protein, but a greater increase in the antioxidative defense system as compared to Saurabh 950. Yield reduction was higher in NDR 97 than in Saurabh 950. This suggested that NDR 97 utilized more photosynthate in maintaining the metabolic machinery against O3 stress leading to lower translocation of photosynthate to reproductive parts. The study concluded that under natural field conditions, physiological and biochemical responses of plants varied with pollutant concentrations leading to different translocation strategies in plants, modifying their yield responses. NDR 97, a fast growing and high yielding cultivar was more

  14. Long term monitoring of open-air monuments under threat: the case study of the "Tombs of the Kings" in Cyprus

    NASA Astrophysics Data System (ADS)

    Agapiou, A.; Lysandrou, V.; Hadjimitsis, D. G.; Alexakis, D. D.; Themistocleous, K.; Michaelides, S.

    2012-04-01

    Since antiquity, Cyprus has been a crossroad were various cultures, arts and ideas were deposited. This is evidenced by its huge archaeological residues spread all over the island. Open to air monuments are being exposed to environmental conditions and without any appropriate measures various deterioration factors may become disastrous. Monitoring Cultural Heritage (CH) Sites and Monuments in Cyprus is commonly based on site observations. However, this procedure which includes data collection, periodical observations and multivariate risk assessment analysis, is difficult to be accomplished with the traditional practices and methods, since it is time consuming and expensive. In contrast, new technologies like satellite sensing sensors and in situ measurements can successfully confront this problem by providing to the scientists an integrated and multi-layer monitoring system for vast areas simultaneously. The present paper describes the registration of deterioration processes in one of the most important archaeological areas in Cyprus, listed in the World's Cultural Heritage Sites, the so called "Tomb of the Kings" at Nea Pafos. This work is a part of the research programme "Managing Cultural Heritage Sites through Space and ground Technologies using Geographical Information Systems: A Pilot application at the archaeological sites of Paphos", funded by the Research Promotion Foundation of Cyprus. The project concerns the region of Paphos district in western Cyprus and it deals with cultural heritage sites managements using integrated space and ground technologies, aiming at risk assessment of the areas under examination. The paper presents the methodological framework of the project with some preliminary results for the long term monitoring of Cultural Heritage Sites based, not only in situ observations, but also on using new technologies such as satellite images for retrieving air pollution, laser scanner, thermo-cameras etc.

  15. Photosynthesis, Productivity, and Yield of Maize Are Not Affected by Open-Air Elevation of CO2 Concentration in the Absence of Drought1[OA

    PubMed Central

    Leakey, Andrew D.B.; Uribelarrea, Martin; Ainsworth, Elizabeth A.; Naidu, Shawna L.; Rogers, Alistair; Ort, Donald R.; Long, Stephen P.

    2006-01-01

    While increasing temperatures and altered soil moisture arising from climate change in the next 50 years are projected to decrease yield of food crops, elevated CO2 concentration ([CO2]) is predicted to enhance yield and offset these detrimental factors. However, C4 photosynthesis is usually saturated at current [CO2] and theoretically should not be stimulated under elevated [CO2]. Nevertheless, some controlled environment studies have reported direct stimulation of C4 photosynthesis and productivity, as well as physiological acclimation, under elevated [CO2]. To test if these effects occur in the open air and within the Corn Belt, maize (Zea mays) was grown in ambient [CO2] (376 μmol mol−1) and elevated [CO2] (550 μmol mol−1) using Free-Air Concentration Enrichment technology. The 2004 season had ideal growing conditions in which the crop did not experience water stress. In the absence of water stress, growth at elevated [CO2] did not stimulate photosynthesis, biomass, or yield. Nor was there any CO2 effect on the activity of key photosynthetic enzymes, or metabolic markers of carbon and nitrogen status. Stomatal conductance was lower (−34%) and soil moisture was higher (up to 31%), consistent with reduced crop water use. The results provide unique field evidence that photosynthesis and production of maize may be unaffected by rising [CO2] in the absence of drought. This suggests that rising [CO2] may not provide the full dividend to North American maize production anticipated in projections of future global food supply. PMID:16407441

  16. Critical Propulsion Components. Volume 4; Inlet and Fan/Inlet Accoustics Team

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Several studies have concluded that a supersonic aircraft, if environmentally acceptable and economically viable, could successfully compete in the 21st century marketplace. However, before industry can commit to what is estimated as a 15 to 20 billion dollar investment, several barrier issues must be resolved. In an effort to address these barrier issues, NASA and Industry teamed to form the High-Speed Research (HSR) program. As part of this program, the Critical Propulsion Components (CPC) element was created and assigned the task of developing those propulsion component technologies necessary to: (1) reduce cruise emissions by a factor of 10 and (2) meet the ever-increasing airport noise restrictions with an economically viable propulsion system. The CPC-identified critical components were ultra-low emission combustors, low-noise/high-performance exhaust nozzles, low-noise fans, and stable/high-performance inlets. Propulsion cycle studies (coordinated with NASA Langley Research Center sponsored airplane studies) were conducted throughout this CPC program to help evaluate candidate components and select the best concepts for the more complex and larger scale research efforts. The propulsion cycle and components ultimately selected were a mixed-flow turbofan (MFTF) engine employing a lean, premixed, prevaporized (LPP) combustor coupled to a two-dimensional mixed compression inlet and a two-dimensional mixer/ejector nozzle. Due to the large amount of material presented in this report, it was prepared in four volumes; Volume 1: Summary, Introduction, and Propulsion System Studies, Volume 2: Combustor, Volume 3: Exhaust Nozzle, and Volume 4: Inlet and Fan/Inlet Acoustic Team.

  17. 33 CFR 334.1310 - Lutak Inlet, Alaska; restricted areas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... areas. 334.1310 Section 334.1310 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1310 Lutak Inlet, Alaska; restricted areas. (a) The areas—(1) Army POL dock restricted area. (i) The waters of Lutak Inlet bounded...

  18. 33 CFR 334.1310 - Lutak Inlet, Alaska; restricted areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... areas. 334.1310 Section 334.1310 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1310 Lutak Inlet, Alaska; restricted areas. (a) The areas—(1) Army POL dock restricted area. (i) The waters of Lutak Inlet bounded...

  19. Aerodynamic and directional acoustic performance of a scoop inlet

    NASA Technical Reports Server (NTRS)

    Abbott, J. M.; Dietrich, D. A.

    1977-01-01

    Aerodynamic and directional acoustic performances of a scoop inlet were studied. The scoop inlet is designed with a portion of the lower cowling extended forward to direct upward any noise that is propagating out the front of the engine toward the ground. The tests were conducted in an anechoic wind tunnel facility at free stream velocities of 0, 18, 41, and 61 m/sec and angles of attack from -10 deg to 120 deg. Inlet throat Mach number was varied from 0.30 to 0.75. Aerodynamically, at a free stream velocity of 41 m/sec, the design throat Mach number (0.63), and an angle of attack of 50 deg, the scoop inlet total pressure recovery was 0.989 and the total pressure distortion was 0.15. The angles of attack where flow separation occurred with the scoop inlet were higher than those for a conventional symmetric inlet. Acoustically, the scoop inlet provided a maximum noise reduction of 12 to 15 db below the inlet over the entire range of throat Mach number and angle of attack at a free-stream velocity of 41 m/sec.

  20. Validation of WIND for a Series of Inlet Flows

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Abbott, John M.; Cavicchi, Richard H.

    2002-01-01

    Validation assessments compare WIND CFD simulations to experimental data for a series of inlet flows ranging in Mach number from low subsonic to hypersonic. The validation procedures follow the guidelines of the AIAA. The WIND code performs well in matching the available experimental data. The assessments demonstrate the use of WIND and provide confidence in its use for the analysis of aircraft inlets.

  1. Isolated testing of highly maneuverable inlet con cepts

    NASA Technical Reports Server (NTRS)

    Norby, W. P.; Haeffele, B. A.; Burley, R. R.

    1986-01-01

    Ten percent scale models of a Mach 2.2 two dimensional inlet and a Mach 2.0 axisymmetric inlet were tested in the NASA Lewis Research Center 8'x6' Supersonic Wind Tunnel as part of a cooperative effort with the McDonnell Aircraft Company. The objective of this effort was to test methods designed to increase the maneuvering performance of fighter aircraft inlets. Maneuvering improvement concepts were tested up to 40-deg angle of attack for Mach numbers of 0.6 and 0.9, and up to 25 deg for Mach numbers 1.2 and 1.4. Maneuvering improvement concepts included a rotating cowl lip, auxiliary inlets aft of the inlet throat, and a retracting centerbody for the axisymmetric inlet. Test results show that the rotating cowl design was effective in improving subsonic maneuvering performance for both inlets. Auxiliary inlets did not produce significant performance increases for either model. The retracted centerbody resulted in some performance benefits at high angles of attack. None of the maneuvering improvement concepts were effective at Mach 1.2 and 1.4.

  2. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  3. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  4. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  5. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  6. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  7. Prevalence of Toxocara cati and other parasites in cats' faeces collected from the open spaces of public institutions: Buenos Aires, Argentina.

    PubMed

    Sommerfelt, I E; Cardillo, N; López, C; Ribicich, M; Gallo, C; Franco, A

    2006-09-10

    Toxocarosis is a worldwide parasitic infection that affects both cats and dogs. Toxocara cati (Schrank, 1788) syn. Toxocara mystax (Zeder, 1800) prevalence was studied in faeces from stray cats collected from the open spaces of public institutions of Buenos Aires city, both building and surrounding open spaces are fenced off. Of the 465 samples obtained from March to June of 2005, 58.3% were found to have parasite eggs. The following parasites were identified from the 271 positive samples: T. cati (61.2%), Cystoisospora spp. (20.3%), Trichuris spp. (17.0%), Toxascaris leonina (15.1%), Ancylostoma spp. (14%) and Aelurostrongylus abstrusus (2.6%). T. cati prevalence was 35.7% (95% confidence interval: 31.2-40.1), with a 42.2% single isolations. The most frequent combination was T. cati and Cystoisospora spp. (9%). More than half the areas studied showed over 40% prevalence. Seventy-one percent of the collected samples were fresh with a variable moist consistency and 29% were older with a dry consistency. A statistically significant association was found between sample consistency and presence of parasites (chi2 = 10.81; p = 0.001) as also between sample consistency and presence of T. cati (chi2 = 11.27; p = 0.0007). Moist consistencies were significantly different from the rest: consistency (wet or dry) versus parasites (z = 1.95; p = 0.02) (95% confidence interval: 0.004-0.203); consistency (wet or dry) versus T. cati (z = 3.25; p = 0.0006) (95% confidence interval: 0.075-0.254). The cat population that inhabits these public green spaces contaminates the environment, thus transforming them into dangerous spaces with a variable rate for the human population that spends time in these places.

  8. Effects of elevated ozone concentration on CH4 and N2O emission from paddy soil under fully open-air field conditions.

    PubMed

    Tang, Haoye; Liu, Gang; Zhu, Jianguo; Kobayashi, Kazuhiko

    2015-04-01

    We investigated the effects of elevated ozone concentration (E-O3) on CH4 and N2O emission from paddies with two rice cultivars: an inbred Indica cultivar Yangdao 6 (YD6) and a hybrid one II-you 084 (IIY084), under fully open-air field conditions in China. A mean 26.7% enhancement of ozone concentration above the ambient level (A-O3) significantly reduced CH4 emission at tillering and flowering stages leading to a reduction of seasonal integral CH4 emission by 29.6% on average across the two cultivars. The reduced CH4 emission is associated with O3-induced reduction in the whole-plant biomass (-13.2%), root biomass (-34.7%), and maximum tiller number (-10.3%), all of which curbed the carbon supply for belowground CH4 production and its release from submerged soil to atmosphere. Although no significant difference was detected between the cultivars in the CH4 emission response to E-O3, a larger decrease in CH4 emission with IIY084 (-33.2%) than that with YD6 (-7.0%) was observed at tillering stage, which may be due to the larger reduction in tiller number in IIY084 by E-O3. Additionally, E-O3 reduced seasonal mean NOx flux by 5.7% and 11.8% with IIY084 and YD6, respectively, but the effects were not significant statistically. We found that the relative response of CH4 emission to E-O3 was not significantly different from those reported in open-top chamber experiments. This study has thus confirmed that increasing ozone concentration would mitigate the global warming potential of CH4 and suggested consideration of the feedback mechanism between ozone and its precursor emission into the projection of future ozone effects on terrestrial ecosystem.

  9. Late Pleistocene steppe lion Panthera leo spelaea (Goldfuss, 1810) footprints and bone records from open air sites in northern Germany - Evidence of hyena-lion antagonism and scavenging in Europe

    NASA Astrophysics Data System (ADS)

    Diedrich, Cajus G.

    2011-07-01

    Bone remains and a trackway of Pantheraichnus bottropensis nov. ichg. ichnsp. of the Late Pleistocene lion Panthera leo spelaea ( Goldfuss, 1810) have been recovered from Bottrop and other open air sites in northern Germany. Some of these bones are from open air hyena den sites. A relative high proportion of lion bones (20%) exhibit bite, chew or nibble marks, or bone crushing and nibbling caused by a large carnivore. Repeated patterns of similar bone damage have been compared to bone remains found at hyena dens in gypsum karst areas and cave sites in northern Germany. Ice Age spotted hyenas have been the main antagonists and the main scavengers on lion carcasses. The remains appear to have been imported often by hyenas into their communal dens, supporting the theory of strong hyena-lion antagonism, similar to the well documented antagonism between modern African lions and spotted hyenas. Most of the lion bones from the open air hyena den at Bottrop are probably a result of such antagonism, as are the rare remains of these carnivores found within large hyena prey bone accumulations along the Pleistocene rivers. The Emscher River terrace also has the largest quantity of hyena remains from open air river terrace sites in northern Germany. Their cub remains, and incomplete chewed prey bones from mammoths and woolly rhinoceroses, typical of hyena activity, underline the character of these sites as cub-raising and communal dens, where their prey was accumulated along the riverbanks in a similar manner to modern African hyenas.

  10. Minimum Weight Design of a Generic Axisymmetric Inlet

    NASA Technical Reports Server (NTRS)

    Nadell, Shari-Beth

    1996-01-01

    A new minimum weight design method for high-speed axisymmetric inlets was demonstrated on a generic inlet. The method uses Classical Beam Theory and shell buckling to determine the minimum required equivalent isotropic thickness for a stiffened shell based on prescribed structural design requirements and load conditions. The optimum spacing and equivalent isotropic thickness of ring frame supports are computed to prevent buckling. The method thus develops a preliminary structural design for the inlet and computes the structural weight. Finite element analyses were performed on the resulting inlet design to evaluate the analytical results. Comparisons between the analytical and finite element stresses and deflections identified areas needing improvement in the analytical method. The addition of the deflection due to shear and a torsional buckling failure mode to the new method brought its results in line with those from the finite element analyses. Final validation of the new method will be made using data from actual inlets.

  11. Inlet flow field investigation. Part 1: Transonic flow field survey

    NASA Technical Reports Server (NTRS)

    Yetter, J. A.; Salemann, V.; Sussman, M. B.

    1984-01-01

    A wind tunnel investigation was conducted to determine the local inlet flow field characteristics of an advanced tactical supersonic cruise airplane. A data base for the development and validation of analytical codes directed at the analysis of inlet flow fields for advanced supersonic airplanes was established. Testing was conducted at the NASA-Langley 16-foot Transonic Tunnel at freestream Mach numbers of 0.6 to 1.20 and angles of attack from 0.0 to 10.0 degrees. Inlet flow field surveys were made at locations representative of wing (upper and lower surface) and forebody mounted inlet concepts. Results are presented in the form of local inlet flow field angle of attack, sideflow angle, and Mach number contours. Wing surface pressure distributions supplement the flow field data.

  12. Catalytically-Promoted Analyte Derivatization Inside a Gas Chromatographic Inlet

    PubMed Central

    Fowler, William K.; Gamble, Kelly J.; Wright, Amber R.

    2010-01-01

    Reported here is a preliminary assessment of the feasibility of catalyzing on-line derivatization reactions inside the inlet (i.e., the injection port) of a gas chromatograph (GC) with solid heterogeneous catalysts. The experiments described here entail the installation of candidate catalysts inside the GC inlet liner and the subsequent injection of analyte/reagent mixtures onto the catalyst beds. Two catalysts are identified, each of which clearly catalyzes one of the chosen model derivatization reactions in the inlet of a GC. This result supports our hypothesis that on-line derivatizations can, in principle, be reproducibly catalyzed inside the GC inlet by solid heterogeneous catalysts and that the presence of such catalysts in the inlet do not necessarily cause a serious loss of instrument performance or chromatographic efficiency. PMID:20822662

  13. Computational Analysis of a Low-Boom Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.

    2011-01-01

    A low-boom supersonic inlet was designed for use on a conceptual small supersonic aircraft that would cruise with an over-wing Mach number of 1.7. The inlet was designed to minimize external overpressures, and used a novel bypass duct to divert the highest shock losses around the engine. The Wind-US CFD code was used to predict the effects of capture ratio, struts, bypass design, and angles of attack on inlet performance. The inlet was tested in the 8-ft by 6-ft Supersonic Wind Tunnel at NASA Glenn Research Center. Test results showed that the inlet had excellent performance, with capture ratios near one, a peak core total pressure recovery of 96 percent, and a stable operating range much larger than that of an engine. Predictions generally compared very well with the experimental data, and were used to help interpret some of the experimental results.

  14. Conceptual study of a turbojet/ramjet inlet

    NASA Technical Reports Server (NTRS)

    Weidner, J. P.

    1979-01-01

    An inlet concept for separate turbojet and ramjet engines was defined and compared with an equivalent inlet for a wraparound turboramjet engine. The comparison was made for a typical high altitude hypersonic cruise vehicle where the turbojet inlet capture area was required to be half as large as the ramjet inlet capture area at cruise. The use of a shorter nacelle having substantially lower cooling requirements at cruise for the inlet concept for separate turbojet and ramjet engines is suggested. The separate engine concept better isolates the turbojet from the ramjet, requires no special close off mechanisms within the turbojet, and avoids the circumferential heat load imposed by a wraparound ramjet. A more variable geometry is required.

  15. Results from computational analysis of a mixed compression supersonic inlet

    NASA Technical Reports Server (NTRS)

    Saunders, J. D.; Keith, T. G.

    1991-01-01

    A numerical study was performed to simulate the critical flow through a supersonic inlet. This flow field has many phenomena such as shock waves, strong viscous effects, turbulent boundary layer development, boundary layer separations, and mass flow suction through the walls, (bleed). The computational tools used were two full Navier-Stokes (FNS) codes. The supersonic inlet that was analyzed is the Variable Diameter Centerbody, (VDC), inlet. This inlet is a candidate concept for the next generation supersonic involved effort in generating an efficient grid geometry and specifying boundary conditions, particularly in the bleed region and at the outflow boundary. Results for a critical inlet operation compare favorably to Method of Characteristics predictions and experimental data.

  16. Admiralty Inlet Hub-Height Turbulence Measurements from June 2012

    DOE Data Explorer

    Kilcher, Levi

    2012-06-18

    This data is from measurements at Admiralty Head, in admiralty inlet. The measurements were made using an IMU equipped ADV mounted on a mooring, the 'Tidal Turbulence Mooring' or 'TTM'. The inertial measurements from the IMU allows for removal of mooring motion in post processing. The mooring motion has been removed from the stream-wise and vertical velocity signals (u, w). The lateral (v) velocity may have some 'persistent motion contamination' due to mooring sway. The ADV was positioned 11m above the seafloor in 58m of water at 48.1515N, 122.6858W. Units ----- - Velocity data (_u, urot, uacc) is in m/s. - Acceleration (Accel) data is in m/s^2. - Angular rate (AngRt) data is in rad/s. - The components of all vectors are in 'ENU' orientation. That is, the first index is True East, the second is True North, and the third is Up (vertical). - All other quantities are in the units defined in the Nortek Manual. Motion correction and rotation into the ENU earth reference frame was performed using the Python-based open source DOLfYN library (http://lkilcher.github.io/dolfyn/). Details on motion correction can be found there. For additional details on this dataset see the included Marine Energy Technology Symposium paper.

  17. A study on flow development in an APU-style inlet and its effect on centrifugal compressor performance

    NASA Astrophysics Data System (ADS)

    Lou, Fangyuan

    The objectives of this research were to investigate the flow development inside an APU-style inlet and its effect on centrifugal compressor performance. The motivation arises from the increased applications of gas turbine engines installed with APU-style inlets such as unmanned aerial vehicles, auxiliary power units, and helicopters. The inlet swirl distortion created from these complicated inlet systems has become a major performance and operability concern. To improve the integration between the APU-style inlet and gas turbine engines, better understanding of the flow field in the APU-style inlet and its effect on gas turbine is necessary. A research facility for the purpose of performing an experimental investigation of the flow field inside an APU-style inlet was developed. A subcritical air ejector is used to continuously flow the inlet at desired corrected mass flow rates. The facility is capable of flowing the APU inlet over a wide range of corrected mass flow rate that matches the same Mach numbers as engine operating conditions. Additionally, improvement in the system operational steadiness was achieved by tuning the pressure controller using a PID control method and utilizing multi-layer screens downstream of the APU inlet. Less than 1% relative unsteadiness was achieved for full range operation. The flow field inside the rectangular-sectioned 90? bend of the APU-style inlet was measured using a 3-Component LDV system. The structures for both primary flow and the secondary flow inside the bend were resolved. Additionally, the effect of upstream geometry on the flow development in the downstream bend was also investigated. Furthermore, a Single Stage Centrifugal Compressor research facility was developed at Purdue University in collaboration with Honeywell to operate the APU-style inlet at engine conditions with a compressor. To operate the facility, extensive infrastructure for facility health monitoring and performance control (including lubrication

  18. Altitude-Wind-Tunnel Investigation of a 3000-Pound-Thrust Axial-Flow Turbojet Engine. 6; Analysis of Effects of Inlet Pressure Losses

    NASA Technical Reports Server (NTRS)

    Sanders, Newell D.; Palasics, John

    1948-01-01

    The losses in the inlet air ducts, the diffusers, and the de-icing equipment associated with turbojet engine installations cause a reduction in the total pressure at the inlet of the engine and result in reduced thrust and increased specific fuel consumption. An analytical evaluation of the effects of inlet losses on the net thrust and the fuel economy of a 3000-pound-thrust axial flow turbojet engine with a two-stage turbine is presented. The analysis is based on engine performance characteristics that were determined from experiments in the NACA Cleveland altitude wind tunnel. The experimental investigation did not include tests in which inlet losses were systematically varied, but the effects of these losses can be accurately estimated from the experimentally determined performance characteristics of the engine.

  19. Effects of radial and circumferential inlet velocity profile distortions on performance of a short-length double-annular ram induction combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.; Perkins, P. J.

    1972-01-01

    Inlet air velocity profile tests were conducted on a full-scale short-length 102-centimeter-diameter annual combustor designed for advanced gas turbine engine applications. The inlet profiles studied include radial distortions that were center peaked, and tip peaked, as well as a circumferential distortion which was center peaked for one-third of the circumference and flat for the other two-thirds. An increase in combustor pressure loss was the most significant effect of the radial air velocity distortions. With the circumferential distortion, exit temperature pattern factor doubled when compared to a flat velocity profile.

  20. Cooling Characteristics of a Pratt and Whitney R-2800 Engine Installed in an NACA Short-nose High-inlet-velocity Cowling

    NASA Technical Reports Server (NTRS)

    Corson, Blake W.; McLellan, Charles H.

    1944-01-01

    An investigation was made of the cooling characteristics of a P and W R-2800 engine with NACA short-nose high inlet-velocity cowling. The internal aerodynamics of the cowling were studied for ranges of propeller-advance ratio and inlet-velocity ratio obtained by deflection of cowling flaps. Tests included variations of engine power, fuel/air ratio and cooling-air pressure drop. Engine cooling data are presented in the form of cooling correlation curves, and an example for calculation of cooling requirements in flight is included.

  1. Investigation of Power Requirements for Ice Prevention and Cyclical De-Icing of Inlet Guide Vanes with Internal Electric Heaters

    NASA Technical Reports Server (NTRS)

    VonGlahn, Uwe; Blatz, Robert E.

    1950-01-01

    An investigation was conducted to determine the electric power requirements necessary for ice protection of inlet guide vanes by continuous heating and by cyclical de-icing. Data are presented to show the effect of ambient-air temperature, liquid-water content, air velocity, heat-on period, and cycle times on the power requirements for these two methods of ice protection. The results showed that for a hypothetical engine using 28 inlet guide vanes under similar icing conditions, cyclical de-icing can provide a total power saving as high as 79 percent over that required for continuous heating. Heat-on periods in the order of 10 seconds with a cycle ratio of about 1:7 resulted in the best over-all performance with respect to total power requirements and aerodynamic losses during the heat-off period. Power requirements reported herein may be reduced by as much as 25 percent by achieving a more uniform surface-temperature distribution. A parameter in terms of engine mass flow, vane size, vane surface temperature, and the icing conditions ahead of the inlet guide vanes.was developed by which an extension of the experimental data to icing conditions and inlet guide vanes, other than those investigated was possible.

  2. Vapor Condensation Control of JP-4 Emissions from Underground Storage Tanks at March Air Force Base, California

    DTIC Science & Technology

    1982-05-01

    recovery units. Scott Total Hydrocarbon Analyzers ( THCAs ) Models 215 and 116 were used at the inlet and outlet sites, respectively. Figures 3 and 4...illustrate the various features of the sampling system. To bring the inlet hydrocarbon concentration measurement into the span range of the Model 215 THCA it...was necessary to dilute the inlet gas with hydrocarbon-free air. The mixed gas was then delivered in excess to the THCA on both inlet and outlet

  3. America's Open-Air Classrooms

    ERIC Educational Resources Information Center

    Matthews, William H., III

    1970-01-01

    Discusses U.S. National Parks as natural laboratories for the study of ecology, geology, earth science, and botany. Suggests activities which will enable children to more fully appreciate the great age of the earth, its history, the complexity of its structure and composition, and the myriad plants and animals which inhabit it. (BR)

  4. Unstart Coupling Mechanism Analysis of Multiple-Modules Hypersonic Inlet

    PubMed Central

    Wang, Lei; Cao, Shibin

    2013-01-01

    The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. The unstarted flowfield and coupling characteristic for a three-module hypersonic inlet caused by center module II and side module III were, conducted respectively. The results indicate that the other two hypersonic inlets are forced into unstarted flow when unstarted phenomenon appears on a single-module hypersonic inlet due to high backpressure, and the reversed flow in the isolator dominates the formation, expansion, shrinkage, and disappearance of the vortexes, and thus, it is the major factor of unstart coupling of multiple-modules hypersonic inlet. The coupling effect among multiple modules makes hypersonic inlet be more likely unstarted. PMID:24348146

  5. Inlet Trade Study for a Low-Boom Aircraft Demonstrator

    NASA Technical Reports Server (NTRS)

    Heath, Christopher M.; Slater, John W.; Rallabhandi, Sriram K.

    2016-01-01

    Propulsion integration for low-boom supersonic aircraft requires careful inlet selection, placement, and tailoring to achieve acceptable propulsive and aerodynamic performance, without compromising vehicle sonic boom loudness levels. In this investigation, an inward-turning streamline-traced and axisymmetric spike inlet are designed and independently installed on a conceptual low-boom supersonic demonstrator aircraft. The airframe was pre-shaped to achieve a target ground under-track loudness of 76.4 PLdB at cruise using an adjoint-based design optimization process. Aircraft and inlet performance characteristics were obtained by solution of the steady-state Reynolds-averaged Navier-Stokes equations. Isolated cruise inlet performance including total pressure recovery and distortion were computed and compared against installed inlet performance metrics. Evaluation of vehicle near-field pressure signatures, along with under- and off-track propagated loudness levels is also reported. Results indicate the integrated axisymmetric spike design offers higher inlet pressure recovery, lower fan distortion, and reduced sonic boom. The vehicle with streamline-traced inlet exhibits lower external wave drag, which translates to a higher lift-to-drag ratio and increased range capability.

  6. Flow Simulation of Supersonic Inlet with Bypass Annular Duct

    NASA Technical Reports Server (NTRS)

    Kim, HyoungJin; Kumano, Takayasu; Liou, Meng-Sing; Povinelli, Louis A.; Conners, Timothy R.

    2011-01-01

    A relaxed isentropic compression supersonic inlet is a new concept that produces smaller cowl drag than a conventional inlet, but incurs lower total pressure recovery and increased flow distortion in the (radially) outer flowpath. A supersonic inlet comprising a bypass annulus to the relaxed isentropic compression inlet dumps out airflow of low quality through the bypass duct. A reliable computational fluid dynamics solution can provide considerable useful information to ascertain quantitatively relative merits of the concept, and further provide a basis for optimizing the design. For a fast and reliable performance evaluation of the inlet performance, an equivalent axisymmetric model whose area changes accounts for geometric and physical (blockage) effects resulting from the original complex three-dimensional configuration is proposed. In addition, full three-dimensional calculations are conducted for studying flow phenomena and verifying the validity of the equivalent model. The inlet-engine coupling is carried out by embedding numerical propulsion system simulation engine data into the flow solver for interactive boundary conditions at the engine fan face and exhaust plane. It was found that the blockage resulting from complex three-dimensional geometries in the bypass duct causes significant degradation of inlet performance by pushing the terminal normal shock upstream.

  7. Minimum fan turbine inlet temperature mode evaluation

    NASA Technical Reports Server (NTRS)

    Orme, John S.; Nobbs, Steven G.

    1995-01-01

    Measured reductions in turbine temperature which resulted from the application of the F-15 performance seeking control (PSC) minimum fan turbine inlet temperature (FTIT) mode during the dual-engine test phase is presented as a function of net propulsive force and flight condition. Data were collected at altitudes of 30,000 and 45,000 feet at military and partial afterburning power settings. The FTIT reductions for the supersonic tests are less than at subsonic Mach numbers because of the increased modeling and control complexity. In addition, the propulsion system was designed to be optimized at the mid supersonic Mach number range. Subsonically at military power, FTIT reductions were above 70 R for either the left or right engines, and repeatable for the right engine. At partial afterburner and supersonic conditions, the level of FTIT reductions were at least 25 R and as much as 55 R. Considering that the turbine operates at or very near its temperature limit at these high power settings, these seemingly small temperature reductions may significantly lengthen the life of the turbine. In general, the minimum FTIT mode has performed well, demonstrating significant temperature reductions at military and partial afterburner power. Decreases of over 100 R at cruise flight conditions were identified. Temperature reductions of this magnitude could significantly extend turbine life and reduce replacement costs.

  8. Observations of Currents in Two Tidally Modulated Inlets

    NASA Astrophysics Data System (ADS)

    Lippmann, T. C.; Irish, J. D.; Hunt, J.

    2012-12-01

    Observations of currents obtained in two tidally modulated inlets are used to examine the spatial evolution of the vertical structure in hourly averaged mean flow and at tidal frequencies. Field experiments of 30 day duration were conducted at Hampton/Seabrook Harbor, NH, in the Fall of 2011 and again at New River Inlet, NC, in the spring of 2012. The temporal variation and vertical structure of the currents were observed with 600 khz and 1200 khz RDI Acoustic Doppler Current Profilers (ADCP) deployed on low-profile bottom tripods just outside and within the inlet mouth, and with a Nortek Aquadopp Profiler mounted on a jetted pipe on the flank of the inlet channel. Across-inlet current profiles were obtained at each site at various tidal stages with a 1200 khz RDI vessel-mounted ADCP onboard the personal watercraft (the Coastal Bathymetry Survey System, or CBASS) that transited the inlet multiple times at various spatial locations. Flows within the inlet were dominated by semi-diurnal tides, ranging from 2.5 to 4 m in elevation at Hampton/Seabrook Harbor with velocities exceeding 3 m/s, and tides ranging from 1 to 1.5 m in elevation at New River Inlet with velocities exceeding 2 m/s. Flows sampled with the CBASS will be used to examine the horizontal and vertical variation in mean currents (averaged over about 20 - 40 min) at various tidal stages. Currents sampled with the fixed instruments will be used to examine the temporal variation in amplitude and direction of mean currents (averaged over 30 - 60 min) as a function of depth, as well as the amplitude, phase, and rotational structure at tidal frequencies. Observations from the two field sites will be compared and discussed in terms of the spatial and temporal evolution from outside the river mouth to the inner inlet channels over the fortnightly sampling period.

  9. Feasibility study of inlet shock stability system of YF-12

    NASA Technical Reports Server (NTRS)

    Blausey, G. C.; Coleman, D. M.; Harp, D. S.

    1972-01-01

    The feasibility of self actuating bleed valves as a shock stabilization system in the inlet of the YF-12 is considered for vortex valves, slide valves, and poppet valves. Analytical estimation of valve performance indicates that only the slide and poppet valves located in the inlet cowl can meet the desired steady state stabilizing flows, and of the two the poppet valve is substantially faster in response to dynamic disturbances. The poppet valve is, therefore, selected as the best shock stability system for the YF-12 inlet.

  10. Distortion-rotor interaction noise produced by a drooped inlet

    NASA Technical Reports Server (NTRS)

    Smith, E. B.; Moore, M. T.; Gliebe, P. R.

    1980-01-01

    The 'drooped' inlet used on most wing mounted engines produces a wall static pressure distortion at the fan face of about plus or minus 2%. The interaction of the fan rotor with this fixed distortion pattern produces blade passing frequency and harmonic tone levels in flight which contribute to forward radiated engine noise spectra. Data from a wind tunnel test, using both a drooped inlet and an inlet with no droop, show large changes in forward radiated noise levels over a limited fan speed range. An analytical model of this fan noise mechanism is developed and is used to account for the major features of the measured results.

  11. High-speed inlet research program and supporting analysis

    NASA Technical Reports Server (NTRS)

    Coltrin, Robert E.

    1990-01-01

    The technology challenges faced by the high speed inlet designer are discussed by describing the considerations that went into the design of the Mach 5 research inlet. It is shown that the emerging three dimensional viscous computational fluid dynamics (CFD) flow codes, together with small scale experiments, can be used to guide larger scale full inlet systems research. Then, in turn, the results of the large scale research, if properly instrumented, can be used to validate or at least to calibrate the CFD codes.

  12. Variable geometry inlet design for scram jet engine

    NASA Technical Reports Server (NTRS)

    Guinan, Daniel P. (Inventor); Drake, Alan (Inventor); Andreadis, Dean (Inventor); Beckel, Stephen A. (Inventor)

    2005-01-01

    The present invention relates to an improved variable geometry inlet for a scram jet engine having at least one combustor module. The variable geometry inlet comprises each combustor module having two sidewalls. Each of the sidewalls has a central portion with a thickness and a tapered profile forward of the central portion. The tapered profile terminates in a sharp leading edge. The variable geometry inlet further comprises each module having a lower wall and a movable cowl flap positioned forward of the lower wall. The movable cowl flap has a leading edge and the leading edges of the sidewalls intersect the leading edge of the cowl flap.

  13. Should we attempt global (inlet engine airframe) control design?

    NASA Technical Reports Server (NTRS)

    Carlin, C. M.

    1980-01-01

    The feasibility of multivariable design of the entire airplane control system is briefly addressed. An intermediate step in that direction is to design a control for an inlet engine augmentor system by using multivariable techniques. The supersonic cruise large scale inlet research program is described which will provide an opportunity to develop, integrate, and wind tunnel test a control for a mixed compression inlet and variable cycle engine. The integrated propulsion airframe control program is also discussed which will introduce the problem of implementing MVC within a distributed processing avionics architecture, requiring real time decomposition of the global design into independent modules in response to hardware communication failures.

  14. Estimation of additive forces and moments for supersonic inlets

    NASA Technical Reports Server (NTRS)

    Perkins, Stanley C., Jr.; Dillenius, Marnix F. E.

    1991-01-01

    A technique for estimating the additive forces and moments associated with supersonic, external compression inlets as a function of mass flow ratio has been developed. The technique makes use of a low order supersonic paneling method for calculating minimum additive forces at maximum mass flow conditions. A linear relationship between the minimum additive forces and the maximum values for fully blocked flow is employed to obtain the additive forces at a specified mass flow ratio. The method is applicable to two-dimensional inlets at zero or nonzero angle of attack, and to axisymmetric inlets at zero angle of attack. Comparisons with limited available additive drag data indicate fair to good agreement.

  15. Esophageal Rings and Stricture Related to a Circumferential Inlet Patch

    PubMed Central

    Scott, Larry

    2016-01-01

    Inlet patches are sometimes seen during upper endoscopy, usually in the proximal esophagus. Complications of inlet patches can cause a wide array of symptoms and complications. A man presented with dysphagia and was found to have 2 rings in the upper esophagus, just above and below a circumferential inlet patch. The more distal ring caused a stenosis, which produced the symptoms. Savary dilation and treatment with a proton pump inhibitor led to symptom resolution. Pathology was missed on the patient's first endoscopy, highlighting the importance of looking for pathology throughout the entire esophagus, not just in the distal esophagus. PMID:27807576

  16. Inlet Particle-Sorting Cyclone for the Enhancement of PM2.5 Separation.

    PubMed

    Fu, Peng-Bo; Wang, Fei; Yang, Xue-Jing; Ma, Liang; Cui, Xin; Wang, Hua-Lin

    2017-02-07

    Many cities are suffering from severe air pollution from fine particulate matter. Cyclone is an effective separator for particulate pollutant but has low efficiency for those with an aerodynamic diameter of 2.5 μm or less (PM2.5). In this research, four novel inlet particle-sorting cyclones were first developed to enhance the separation of PM2.5. The energy consumption, overall separation efficiency, particle grade efficiency,outlet particle concentration and size distribution were compared with common cyclone (CM-C). It was found that the vertical reverse rotation cyclone (VRR-C), which made the smaller particles enter cyclone from radially outer side and axially lower side at the rectangular inlet, had the best separation performance, especially for PM2.5 separation. The mean diameter of inlet particles was 15.7 μm and the particle concentration was 2000 mg/m(3), the overall separation efficiency of the VRR-C reached 98.3%, which was 6.4% higher than that of CM-C. PM2.5 grade efficiency of the VRR-C exceeded 80%, which was 15∼20% higher than that of CM-C. The PM2.5 content at the VRR-C outlet was 30.8 mg/m(3), while that of CM-C was still 118.4 mg/m(3). The novel inlet particle-sorting cyclone is an effective separation enhancement for PM2.5 source control in the process of industrial production and environment protection.

  17. An investigation of air solubility in Jet A fuel at high pressures

    NASA Technical Reports Server (NTRS)

    Faeth, G. M.

    1981-01-01

    Problems concerned with the supercritical injection concept are discussed. Supercritical injection involves dissolving air into a fuel prior to injection. A similar effect is obtained by preheating the fuel so that a portion of the fuel flashes when its pressure is reduced. Flashing improves atomization properties and the presence of air in the primary zone of a spray flame reduces the formation of pollutants. The investigation is divided into three phases: (1) measure the solubility and density properties of fuel/gas mixtures, including Jet A/air, at pressures and correlate these results using theory; (2) investigate the atomization properties of flashing liquids, including fuel/dissolved gas systems. Determine and correlate the effect of inlet properties and injector geometry on mass flow rates, Sauter mean diameter and spray angles; (3) examine the combustion properties of flashing injection in an open burner flame, considering flame shape and soot production.

  18. Secondary gas emissions during coal desorption, Marathon Grassim Oskolkoff-1 Well, Cook Inlet Basin, Alaska: Implications for resource assessment

    USGS Publications Warehouse

    Barker, C.E.; Dallegge, T.

    2006-01-01

    Cuttings samples of sub-bituminous humic coals from the Oligocene to Pliocene Tyonek Formation, Cook Inlet Basin, Alaska show secondary gas emissions whose geochemistry is consistent with renewed microbial methanogenesis during canister desorption. The renewed methanogenesis was noted after initial desorption measurements had ceased and a canister had an air and desorbed gas mixture backflow into the canister during a measurement. About a week after this event, a secondary emission of gas began and continued for over two years. The desorbed gas volume reached a new maximum, increasing the total from 3.3 to 4.9 litres, some 48% above the pre-contamination total volume. The gases released during desorption show a shift in the isotopic signature over time of methane from ??13CCH4 of -53.60 ??? and ??DCH4 of -312.60 ??? at the first day to ??13CCH4 of -57.06 ??? and ??DCH4 of -375.80 ??? after 809 days, when the experiment was arbitrarily stopped and the canister opened to study the coal. These isotopic data, interpreted using a Bernard Diagram, indicate a shift from a mixed thermogenic and biogenic source typical of natural gases in the coals and conventional gas reservoirs of the Cook Inlet Basin to a likely biogenic acetate-fermentation methane source. However, the appearance of CO2 during the renewed gas emissions with a ??13CCO2 of +26.08 to +21.72 ???, interpreted using the carbon isotope fractions found for acetate fermentation and CO2 reduction between CO2 and CH4 by Jenden and Kaplan (1986), indicates a biogenic CO2-reduction pathway may also be operative during renewed gas emission. Adding nutrients to the coal cuttings and canister water and culturing the microbial consortia under anaerobic conditions led to additional methane-rich gas generation in the laboratory. After this anaerobic culturing, ultraviolet microscopy showed that canister water contained common, fluorescent, rod-like microbes comparable to Methanobacterium sp. Scanning electron microscope

  19. Experimental investigation of tangential blowing for control of the strong shock boundary layer interaction on inlet ramps

    NASA Technical Reports Server (NTRS)

    Schwendemann, M. F.

    1981-01-01

    A 0.165-scale isolated inlet model was tested in the NASA Lewis Research Center 8-ft by 6-ft Supersonic Wind Tunnel. Ramp boundary layer control was provided by tangential blowing from a row of holes in an aft-facing step set into the ramp surface. Testing was performed at Mach numbers from 1.36 to 1.96 using both cold and heated air in the blowing system. Stable inlet flow was achieved at all Mach numbers. Blowing hole geometry was found to be significant at 1.96M. Blowing air temperature was found to have only a small effect on system performance. High blowing levels were required at the most severe test conditions.

  20. An Investigation of the Icing and Heated-air De-icing Characteristics of the R-2600-13 Induction System

    NASA Technical Reports Server (NTRS)

    Chapman, Gilbert E.

    1946-01-01

    A laboratory investigation was made on a Holley 1685-HB carburetor mounted on an R-2600-13 supercharger assembly to determine the icing characteristics and the heated-air de-icing requirements of this portion of the B-25D airplane induction system. Icing has been found to be most prevalent at relatively small throttle openings and, consequently, all runs were made at simulated 60-percent normal rated power condition. Icing characteristics were determined during a series of 15-minute runs over a range of inlet-air conditions. For the de-icing investigation severe impact ice was allowed to form in the induction system and the time required for the recovery of 95 percent of the maximum possible air flow at the original throttle setting was then determined for a range of wet-bulb temperatures. Results of these runs showed that ice on the walls of the carburetor adapter and on the rim of the impeller-shroud portion of the supercharger diffuser plate did not affect engine operation at 60-percent normal rated power. Ice that adversely affected the air flow and the fuel-air ratio was formed only on the central web of the carburetor and then only when the inlet air was saturated or contained free moisture in excess of saturation. No serious ice formations were observed at inlet-air temperatures above 66 0 F or with an inlet-air enthalpy greater than 34 Btu per pound. The maximum temperature at. which any trace of icing could be detected was 1110 F with a relative humidity of approximately 28 percent, The air-flow recovery time for emergency de-icing was 0.3 minute for.an enthalpy of 35 Btu per pound or wet-bulb temperature of 68 0 F. Further increase in enthalpy and wet-bulb temperature above these values resulted in very slight improvement in recovery time. The fuel-air ratio restored by a 5-Minute application of heated air was approximately 7 percent less than the initial value for cold-air conditions.

  1. INTERIOR GUEST BATH, LOOKING NORTHWEST. Oregon Inlet Coast Guard ...

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

    INTERIOR GUEST BATH, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  2. INTERIOR INNKEEPER FAMILY ROOM, LOOKING NORTH. Oregon Inlet Coast ...

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

    INTERIOR INNKEEPER FAMILY ROOM, LOOKING NORTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  3. INTERIOR BUNK ROOM C, LOOKING NORTHWEST. Oregon Inlet Coast ...

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

    INTERIOR BUNK ROOM C, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  4. INTERIOR BUNK ROOM A, LOOKING SOUTHEAST. Oregon Inlet Coast ...

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

    INTERIOR BUNK ROOM A, LOOKING SOUTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  5. INTERIOR GUEST BEDROOM, LOOKING NORTHWEST. Oregon Inlet Coast Guard ...

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

    INTERIOR GUEST BEDROOM, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  6. INTERIOR GUEST BEDROOM, LOOKING SOUTHEAST. Oregon Inlet Coast Guard ...

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

    INTERIOR GUEST BEDROOM, LOOKING SOUTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  7. INTERIOR TOWER ROOM, LOOKING SOUTHWEST. Oregon Inlet Coast Guard ...

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

    INTERIOR TOWER ROOM, LOOKING SOUTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  8. INTERIOR LIBRARY HALL, LOOKING WEST. Oregon Inlet Coast Guard ...

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

    INTERIOR LIBRARY HALL, LOOKING WEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  9. INTERIOR TOWER STAIRS FIRST LEVEL, LOOKING EAST. Oregon Inlet ...

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

    INTERIOR TOWER STAIRS FIRST LEVEL, LOOKING EAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  10. INTERIOR BUNK ROOM C, LOOKING SOUTHEAST. Oregon Inlet Coast ...

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

    INTERIOR BUNK ROOM C, LOOKING SOUTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  11. INTERIOR TOWER ENTRANCE, LOOKING NORTH. Oregon Inlet Coast Guard ...

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

    INTERIOR TOWER ENTRANCE, LOOKING NORTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  12. INTERIOR HALL BY TOWER STAIRS, LOOKING SOUTH. Oregon Inlet ...

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

    INTERIOR HALL BY TOWER STAIRS, LOOKING SOUTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  13. INTERIOR LIBRARY, LOOKING NORTHWEST. Oregon Inlet Coast Guard Station, ...

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

    INTERIOR LIBRARY, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  14. INTERIOR INNKEEPER FAMILY ROOM, LOOKING WEST. Oregon Inlet Coast ...

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

    INTERIOR INNKEEPER FAMILY ROOM, LOOKING WEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  15. INTERIOR BUNK ROOM B, LOOKING WEST. Oregon Inlet Coast ...

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

    INTERIOR BUNK ROOM B, LOOKING WEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  16. INTERIOR TOWER ENTRANCE HALL, LOOKING NORTHWEST. Oregon Inlet Coast ...

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

    INTERIOR TOWER ENTRANCE HALL, LOOKING NORTHWEST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  17. INTERIOR LIBRARY, LOOKING SOUTHEAST. Oregon Inlet Coast Guard Station, ...

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

    INTERIOR LIBRARY, LOOKING SOUTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  18. LOOKOUT TOWER DETAILS, SHEET 5 OF 6. Oregon Inlet ...

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

    LOOKOUT TOWER DETAILS, SHEET 5 OF 6. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  19. STRUCTURAL FLOOR PLAN, SHEET 2 OF 6. Oregon Inlet ...

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

    STRUCTURAL FLOOR PLAN, SHEET 2 OF 6. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  20. INTERIOR TOWER ROOM LOOKING NORTHEAST. Oregon Inlet Coast Guard ...

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

    INTERIOR TOWER ROOM LOOKING NORTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC