Note: This page contains sample records for the topic inlet coolant temperature from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
1

Experiments on the influence of inlet charge and coolant temperature on performance and emissions of a DI Diesel engine  

SciTech Connect

The coolant and inlet charge temperature influence the emissions and performances of a DI Diesel engine. A unique test rig was constructed in which their influence could be studied controlling all the important operational parameters of the engine. The air, fuel and EGR circuit of one cylinder of a four cylinder engine were separated to permit a precise control of flow rates and flow temperatures while the original coolant circuit, controlling the wall temperatures, was preserved. The installation demonstrates how a multi-cylinder production engine can be transformed to perform tests with single cylinder precision. For three operating points, representative for the European homologation cycle, tests were performed to assess the influence of the coolant- and air-temperature on engine operation. Raising the coolant and inlet charge temperature diminishes hydrocarbon emissions and increases NO{sub x} emissions. The effect of the inlet charge temperature is much more important than the effect of the coolant temperature. At low load the effects are more pronounced. The influence on the performance and the combustion process is limited. (author)

Torregrosa, A.J.; Olmeda, P.; Martin, J.; Degraeuwe, B. [CMT-Motores Termicos, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)

2006-07-15

2

Experiments on the influence of inlet charge and coolant temperature on performance and emissions of a DI Diesel engine  

Microsoft Academic Search

The coolant and inlet charge temperature influence the emissions and performances of a DI Diesel engine. A unique test rig was constructed in which their influence could be studied controlling all the important operational parameters of the engine. The air, fuel and EGR circuit of one cylinder of a four cylinder engine were separated to permit a precise control of

A. J. Torregrosa; P. Olmeda; J. Martín; B. Degraeuwe

2006-01-01

3

Design of an Alternative Coolant Inlet Flow Configuaration for the Modular Helium Reactor.  

National Technical Information Service (NTIS)

The coolant outlet temperature for the Modular Helium Reactor (MHR) was increased to improve the overall efficiency of nuclear hydrogen production using either thermochemical or high temperature electrolysis (HTE) processes. The inlet temperature was also...

A. Shenoy E. A. Harvego K. L. Peddicord M. Richards S. M. Mohsin-Reza

2006-01-01

4

Turbine vane coolant flow variations and calculated effects on metal temperatures  

NASA Technical Reports Server (NTRS)

Seventy-two air-cooled turbine vanes were tested to determine coolant flow variations among the vanes. Calculations were made to estimate the effect of measured coolant flow variations on local vane metal temperatures. The calculations were based on the following assumed operating conditions: turbine inlet temperature, 1700 K (2600 F); turbine inlet pressure, 31 N/sq cm (45 psia); coolant inlet temperature, 811 K (1000 F); and total coolant to gas flow ratio, 0.065. Variations of total coolant flow were not large (about 10 percent from the arithmetic mean) for all 72 vanes, but variations in local coolant flows were large. The local coolant flow variations ranged from 8 to 75 percent, and calculated metal temperature variations ranged from 8 to 60 K (15 to 180 F).

Yeh, F. C.; Meitner, P. L.; Russell, L. M.

1975-01-01

5

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

6

Predicted inlet gas temperatures for tungsten fiber reinforced superalloy turbine blades  

NASA Technical Reports Server (NTRS)

Tungsten fiber reinforced superalloy composite (TFRS) impingement cooled turbine blade inlet gas temperatures were calculated taking into account material spanwise strength, thermal conductivity, material oxidation resistance, fiber-matrix interaction, and coolant flow. Measured values of TFRS thermal conductivities are presented. Calculations indicate that blades made of 30 volume percent fiber content TFRS having a 12,000 N-m/kg stress-to-density ratio while operating at 40 atmospheres and a 0.06 coolant flow ratio could permit a turbine blade inlet gas temperature of over 1900K. This is more than 150K greater than similar superalloy blades.

Winsa, E. A.; Westfall, L. J.; Petrasek, D. W.

1978-01-01

7

The effect of inlet gas temperatures on heated humidifier performance.  

PubMed

The aim of the current study was to determine the temperature range of gas at the point at which it passes into a heated humidifier within an intensive care unit and to experimentally examine the effect of different inlet gas temperatures on the performance of a heated humidifier. Various gas and ambient temperatures were measured in an intensive care unit and within ventilator circuits. Ventilator oxygen and air inlet temperatures, ventilator gas outlet temperatures, and humidifier gas inlet temperatures were measured in conjunction with the use of a number of ventilators. Ambient temperatures within the ward ranged from 22.8 degrees C to 28.9 degrees C, while typical ward humidifier gas inlet temperatures ranged from 24.3 degrees C to 28.8 degrees C. Humidity output from a heated humidifier was then determined in an experimental setup at controlled levels of inlet gas temperature using a constant gas flow. A decrease in humidity production, from approximately 36 mg/L at a humidifier inlet gas temperature of 18 degrees C, to 26 mg/L at a humidifier inlet gas temperature of 32 degrees C, was observed with increasing gas inlet temperature. We conclude that humidity output from a heated humidifier varies with inlet gas temperature, decreasing as inlet gas temperature increases. Inlet gas temperatures above 26 degrees C may result in inadequate humidification. PMID:12006141

Carter, Bradley G; Whittington, Naomi; Hochmann, Mark; Osborne, Anthony

2002-01-01

8

Minimum fan turbine inlet temperature mode evaluation  

NASA Technical Reports Server (NTRS)

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.

Orme, John S.; Nobbs, Steven G.

1995-01-01

9

Cooling Characteristics of the V-1650-7 Engine. II - Effect of Coolant Conditions on Cylinder Temperatures and Heat Rejection at Several Engine Powers  

NASA Technical Reports Server (NTRS)

An investigation has been conducted on a V-1650-7 engine to determine the cylinder temperatures and the coolant and oil heat rejections over a range of coolant flows (50 to 200 gal/min) and oil inlet temperatures (160 to 2150 F) for two values of coolant outlet temperature (250 deg and 275 F) at each of four power conditions ranging from approximately 1100 to 2000 brake horsepower. Data were obtained for several values of block-outlet pressure at each of the two coolant outlet temperatures. A mixture of 30 percent by volume of ethylene glycol and 70-percent water was used as the coolant. The effect of varying coolant flow, coolant outlet temperature, and coolant outlet pressure over the ranges investigated on cylinder-head temperatures was small (0 deg to 25 F) whereas the effect of increasing the engine power condition from ll00 to 2000 brake horsepower was large (maximum head-temperature increase, 110 F).

Povolny, John H.; Bogdan, Louis J.; Chelko, Louis J.

1947-01-01

10

The behavior of reactor power and flux resulting from changes in core-coolant temperature for a miniature neutron source reactor  

Microsoft Academic Search

In this work, measurements were performed to verify the theoretical predictions of reactor power and flux parameters that result from changes in core inlet temperature (Tin) and the temperature difference between the coolant inlet and outlet (?T) in the Nigeria Research Reactor-1 (NIRR-1), which is a Miniature Neutron Source Reactor (MNSR). The measured data shows that there is a strong

Y. A. Ahmed; G. I. Balogun; S. A. Jonah; I. I. Funtua

2008-01-01

11

Ultra-lean combustion at high inlet temperatures  

NASA Technical Reports Server (NTRS)

Combustion at inlet air temperatures of 1100 to 1250 K was studied for application to advanced automotive gas turbine engines. Combustion was initiated by the hot environment, and therefore no external ignition source was used. Combustion was stabilized without a flameholder. The tests were performed in a 12 cm diameter test section at a pressure of 2.5 x 10 to the 5th power Pa, with reference velocities of 32 to 60 m/sec and at maximum combustion temperatures of 1350 to 1850 K. Number 2 diesel fuel was injected by means of a multiple source fuel injector. Unburned hydrocarbons emissions were negligible for all test conditions. Nitrogen oxides emissions were less than 1.9 g NO2/kg fuel for combustion temperatures below 1680 K. Carbon monoxide emissions were less than 16 g CO/kg fuel for combustion temperatures greater than 1600 K, inlet air temperatures higher than 1150 K, and residence times greater than 4.3 microseconds.

Anderson, D. N.

1981-01-01

12

Research of pulse tube refrigerator with high and low temperature double-inlet  

Microsoft Academic Search

Through analyzing phase relation between pressures and flow characteristics of double-inlet and multi-bypass, mechanism of double-inlet to lower the temperature of pulse tube refrigerator is proposed. Then another proposal is put forward to replace the low temperature multi-bypass valve, which is another double-inlet valve at room temperature and a small tube prolonging to the low temperature part of pulse tube.

Luwei Yang; Yuan Zhou; Jiangtao Liang

1999-01-01

13

Development of a prototype automatic controller for liquid cooling garment inlet temperature  

NASA Technical Reports Server (NTRS)

The development of a computer control of a liquid cooled garment (LCG) inlet temperature is descirbed. An adaptive model of the LCG is used to predict the heat-removal rates for various inlet temperatures. An experimental system that contains a microcomputer was constructed. The LCG inlet and outlet temperatures and the heat exchanger outlet temperature form the inputs to the computer. The adaptive model prediction method of control is successful during tests where the inlet temperature is automatically chosen by the computer. It is concluded that the program can be implemented in a microprocessor of a size that is practical for a life support back-pack.

Weaver, C. S.; Webbon, B. W.; Montgomery, L. D.

1982-01-01

14

BWR Loss-of-Coolant Accident Tests at ROSA-III with High Temperature Emergency Core Coolant Injection  

Microsoft Academic Search

The effects of emergency core coolant (ECC) temperature on the performance of the emergency core cooling system (ECCS) during a loss-of-coolant accident (LOCA) of a boiling water reactor (BWR) were investigated experimentally using the Rig of Safety Assessment (ROSA)-III integral test facility. The ECC temperature had no direct influence on the ECCS core cooling performance, since ECC became nearly saturated

Hideo NAKAMURA; Yutaka KUKITA; Kanji TASAKA

1988-01-01

15

Self-actuated nuclear reactor shutdown system using induction pump to facilitate sensing of core coolant temperature  

DOEpatents

A self-actuated shutdown system incorporated into a reactivity control assembly in a nuclear reactor includes pumping means for creating an auxiliary downward flow of a portion of the heated coolant exiting from the fuel assemblies disposed adjacent to the control assembly. The shutdown system includes a hollow tubular member which extends through the outlet of the control assembly top nozzle so as to define an outer annular flow channel through the top nozzle outlet separate from an inner flow channel for primary coolant flow through the control assembly. Also, a latching mechanism is disposed in an inner duct of the control assembly and is operable for holding absorber bundles in a raised position in the control assembly and for releasing them to drop them into the core of the reactor for shutdown purposes. The latching mechanism has an inner flow passage extending between and in flow communication with the absorber bundles and the inner flow channel of the top nozzle for accommodating primary coolant flow upwardly through the control assembly. Also, an outer flow passage separate from the inner flow passage extends through the latching mechanism between and in flow communication with the inner duct and the outer flow channel of the top nozzle for accommodating inflow of a portion of the heated coolant from the adjacent fuel assemblies. The latching mechanism contains a magnetic material sensitive to temperature and operable to cause mating or latching together of the components of the latching mechanism when the temperature sensed is below a known temperature and unmating or unlatching thereof when the temperature sensed is above a given temperature. The temperature sensitive magnetic material is positioned in communication with the heated coolant flow through the outer flow passage for directly sensing the temperature thereof. Finally, the pumping means includes a jet induction pump nozzle and diffuser disposed adjacent the bottom nozzle of the control assembly and in flow communication with the inlet thereof. The pump nozzle is operable to create an upward driving flow of primary coolant through the pump diffuser and then to the absorber bundles. The upward driving flow of primary coolant, in turn, creates a suction head within the outer flow channel of the top nozzle and thereby an auxiliary downward flow of the heated coolant portion exiting from the upper end of the adjacent fuel assemblies through the outer flow channel to the pump nozzle via the outer flow passage of the latching mechanism and an annular space between the outer and inner spaced ducts of the control assembly housing. The temperature of the heated coolant exiting from the adjacent fuel assemblies can thereby be sensed directly by the temperature sensitive magnetic material in the latching mechanism.

Sievers, Robert K. (N. Huntingdon, PA); Cooper, Martin H. (Churchill, PA); Tupper, Robert B. (Greensburg, PA)

1987-01-01

16

Design of a reactor inlet temperature controller for EBR-2 using state feedback  

SciTech Connect

A new reactor inlet temperature controller for pool type liquid-metal reactors has been developed and will be tested in EBR-II. The controller makes use of modern control techniques to take into account stratification and mixing in the cold pool during normal operation. Secondary flowrate is varied so that the reactor inlet temperature tracks a setpoint while reactor outlet temperature, primary flowrate and secondary cold leg temperature are treated as exogenous disturbances and are free to vary. A disturbance rejection technique minimizes the effect of these disturbances on inlet temperature. A linear quadratic regulator improves inlet temperature response. Tests in EBR-II will provide experimental data for assessing the performance improvements that modern control can produce over the existing EBR-II analog inlet temperature controller. 10 refs., 8 figs.

Vilim, R.B.; Planchon, H.P.

1990-01-01

17

Effect of Coolant Temperature and Mass Flow on Film Cooling of Turbine Blades  

NASA Technical Reports Server (NTRS)

A three-dimensional Navier Stokes code has been used to study the effect of coolant temperature, and coolant to mainstream mass flow ratio on the adiabatic effectiveness of a film-cooled turbine blade. The blade chosen is the VKI rotor with six rows of cooling holes including three rows on the shower head. The mainstream is akin to that under real engine conditions with stagnation temperature = 1900 K and stagnation pressure = 3 MPa. Generally, the adiabatic effectiveness is lower for a higher coolant temperature due to nonlinear effects via the compressibility of air. However, over the suction side of shower-head holes, the effectiveness is higher for a higher coolant temperature than that for a lower coolant temperature when the coolant to mainstream mass flow ratio is 5% or more. For a fixed coolant temperature, the effectiveness passes through a minima on the suction side of shower-head holes as the coolant to mainstream mass flow, ratio increases, while on the pressure side of shower-head holes, the effectiveness decreases with increase in coolant mass flow due to coolant jet lift-off. In all cases, the adiabatic effectiveness is highly three-dimensional.

Garg, Vijay K.; Gaugler, Raymond E.

1997-01-01

18

Response of a small-turboshaft-engine compression system to inlet temperature distortion  

NASA Technical Reports Server (NTRS)

An experimental investigation was conducted into the response of a small-turboshaft-engine compression system to steady-state and transient inlet temperature distortions. Transient temperature ramps range from less than 100 K/sec to above 610 K/sec and generated instantaneous temperatures to 420 K above ambient. Steady-state temperature distortion levels were limited by the engine hardware temperature list. Simple analysis of the steady-state distortion data indicated that a particle separator at the engine inlet permitted higher levels of temperature distortion before onset of compressor surge than would be expected without the separator.

Biesiadny, T. J.; Klann, G. A.; Little, J. K.

1984-01-01

19

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

NASA Astrophysics Data System (ADS)

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.

Maqsood, Omar Shahzada

20

Compatibility Issues for a High Temperature Dual Coolant Blanket  

SciTech Connect

One proposed U.S. test blanket module (TBM) for ITER uses ferritic-martensitic alloys with both eutectic Pb-Li and He coolants at {approx}475 C. In order for this blanket concept to operate at higher temperatures ({approx}750 C) for a DEMO-type reactor, several Pb-Li compatibility issues need to be addressed. A SiC/SiC composite flow channel insert is proposed to reduce the steel dissolution rate (and the magnetohydrodynamic pressure drop). Prior capsule testing examined dense, high-purity SiC in Pb-Li at 800-1200 C and found detectable levels of Si in the Pb-Li after 2,000h at 1100 C and 1,000h at 1200 C. Current capsule experiments are examining several different SiC/SiC composite materials at 1000 C. Another issue involves Pb-Li transport between the first wall and heat exchanger. Aluminide coatings on type 316 stainless steel and Al-containing alloys capable of forming an external alumina scale have been studied in capsule experiments at 700 and 800 C for 1,000h. Model aluminide coatings made by chemical vapor deposition reduced the dissolution rate for 316SS at 800 C by a factor of 50.

Pint, Bruce A [ORNL

2007-01-01

21

Effect of Coolant Temperature and Mass Flow on Film Cooling of Turbine Blades.  

National Technical Information Service (NTIS)

A three-dimensional Navier Stokes code has been used to study the effect of coolant temperature, and coolant to mainstream mass flow ratio on the adiabatic effectiveness of a film-cooled turbine blade. The blade chosen is the VKI rotor with six rows of co...

V. K. Garg R. E. Gaugler

1997-01-01

22

Measurement of the Coolant Channel Temperatures and Pressures of a Cooled Radial-Inflow Turbine  

NASA Technical Reports Server (NTRS)

Instrumentation has been installed on the surface of a cooled radial-inflow turbine. Thermocouples and miniature integrated sensor pressure transducers were installed to measure steady state coolant temperatures, blade wall temperatures, and coolant pressures. These measurements will eventually be used to determine the heat transfer characteristics of the rotor. This paper will describe the procedures used to install and calibrate the instrumentation and the testing methods followed. A limited amount of data will compare the measured values to the predicted values.

Dicicco, L. Danielle; Nowlin, Brent C.; Tirres, Lizet

1994-01-01

23

Evaporative spray cooling of power electronics using high temperature coolant  

Microsoft Academic Search

A pressure atomized evaporative spray cooling nozzle array was used to thermally manage the power electronics of a 3 phase inverter module. The module tested was a COTS module manufactured by Semikron, Inc., and has a maximum DC power input of 180 kW (450 VDC and 400 A) with 25degC coolant. However, the standard heat sink that the module uses

Louis J. Turek; Daniel P. Rini; Benjamin A. Saarloos; Louis C. Chow

2008-01-01

24

Analysis for predicting adiabatic wall temperatures with single hole coolant injection into a low speed crossflow  

NASA Technical Reports Server (NTRS)

Assuming the local adiabatic wall temperature equals the local total temperature in a low speed coolant mixing layer, integral conservation equations with and without the boundary layer effects are formulated for the mixing layer downstream of a single coolant injection hole oriented at a 30 degree angle to the crossflow. These equations are solved numerically to determine the center line local adiabatic wall temperature and the effective coolant coverage area. Comparison of the numerical results with an existing film cooling experiment indicates that the present analysis permits a simplified but reasonably accurate prediction of the centerline effectiveness and coolant coverage area downstream of a single hole crossflow streamwise injection at 30 degree inclination angle.

Wang, C. R.; Papell, S. S.; Graham, R. W.

1981-01-01

25

Analysis for predicting adiabatic wall temperatures with single hole coolant injection into a low speed crossflow  

NASA Technical Reports Server (NTRS)

Assuming the local adiabatic wall temperature equals the local total temperature in a low speed coolant mixing layer, integral conservation equations with and without the boundary layer effects are formulated for the mixing layer downstream of a single coolant injection hole oriented at a 30 degree angle to the crossflow. These equations are solved numerically to determine the center-line local adiabatic wall temperature and the effective coolant coverage area. Comparison of the numerical results with an existing film cooling experiment indicates that the present analysis permits a simplified but reasonably accurate prediction of the centerline effectiveness and coolant coverage area downstream of a single hole crossflow streamwise injection at 30-deg inclination angle.

Wang, C. R.; Papell, S. S.; Graham, R. W.

1981-01-01

26

Effects of Non-Uniform Inlet Temperature Distribution on High-Pressure Turbine Blade Loading  

NASA Astrophysics Data System (ADS)

The effects of a non-uniform inlet field on the performance of a commercial, transonic, single-stage, high-pressure, axial turbine with a curved inlet duct have been investigated numerically by solving the unsteady Reynolds-averaged Navier-Stokes equations with the shear stress transport (SST) turbulence model. By adjusting the alignment of the experimentally-based inlet temperature field with respect to the stator vanes, two clocking configurations were generated: a Vane-Impinging (VI) case, in which each hot streak impinged on a vane and a Mid-Pitch (MP) case, in which each hot streak passed between two vanes. An additional case with a purely radial (PR) variation of inlet temperature was also investigated. In the VI case, it was observed that, as the hot streaks impinged on the stator vanes, they spread spanwise due to the actions of the casing passage vortices and the radial pressure gradient; this resulted in a stream entering the rotor with relatively low temperature variations. In the MP case, the hot streaks were convected undisturbed past the relatively cool vane section. Relatively high time-averaged enthalpy values were found to occur on the pressure side of the blades in the MP configuration.

Smith, Craig I.; Chang, Dongil; Tavoularis, Stavros

2012-09-01

27

Nuclear reactor coolant recirculation  

SciTech Connect

A system is described for forcing a liquid water coolant to recirculate through an unshrouded nuclear core in a pressure vessel. The core includes an array of spaced fuel assemblies supported between a lower core support member and an upper core support member. Each of the fuel assemblies is fitted with a tubular flow channel for containing water coolant flowing therethrough; an annular lower support ring attached to the pressure vessel and connected to the lower core support member for support thereof. The lower core support member, the lower support ring and the lower part of the pressure vessel form a lower plenum wherein the coolant can be pressurized. An upper support ring is attached to the pressure vessel and connected to the upper core support member. A space in the pressure vessel above the upper core support member forms an upper plenum for containing water coolant. Coolant pressurizers within the pressure vessel each have a coolant inlet and a coolant outlet and vertically oriented elongated coolant conducts conduits positioned in radially spaced relation between the core and the inner wall of the pressure vessel and extends from the upper plenum to the lower plenum. Each is connected to the coolant inlet of a respective one of the coolant pressurizers and each penetrates the upper support ring for conducting coolant from the upper plenum to the coolant inlet. The coolant outlet of each coolant pressurizer is in fluid communication with the lower plenum for pressurizing the coolant therein. Primary coolant passages are through the lower support member for admitting a pressurized coolant from the lower plenum into the fuel assemblies; and coolant outlet means at the upper end of the core are for discharging liquid coolant from the core to the upper plenum whereby the coolant is recirculated from the lower plenum, through the core to the upper plenum and back to the lower plenum.

Hobson, R.R.

1987-09-29

28

Effect of coolant temperature and mass flow on film cooling of turbine blades  

Microsoft Academic Search

A three-dimensional Navier-Stokes code has been used to study the effect of coolant temperature, and coolant to mainstream mass flow ratio on the adiabatic effectiveness of a film-cooled turbine blade. The blade chosen is the VKI rotor with six rows of cooling holes including three rows on the shower head. The mainstream is akin to that under real engine conditions

Raymond E. Gaugler

1997-01-01

29

The advanced high-temperature reactor: High-temperature fuel, liquid salt coolant, liquid-metal-reactor plant  

Microsoft Academic Search

The Advanced High-Temperature Reactor is a new reactor concept that combines four existing technologies in a new way: (1) coated-particle graphite-matrix nuclear fuels (traditionally used for helium-cooled reactors), (2) Brayton power cycles, (3) passive safety systems and plant designs from liquid-metal-cooled fast reactors, and (4) low-pressure liquid-salt coolants with boiling points far above the maximum coolant temperature. The new combination

Charles Forsberg

2005-01-01

30

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

NASA Technical Reports Server (NTRS)

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.

Anderson, D. N.

1978-01-01

31

Estimation of FBR MONJU's Average Fuel Temperatures and Fuel-to-coolant Heat Transfer Coefficients using Trip-Test Data  

Microsoft Academic Search

Fuel temperature is an important parameter in reactor safety. However, temperatures of fuel sub-assemblies in power reactors usually cannot be directly measured. A means therefore has been devised to use heat removed by coolant from fuel sub-assemblies following a reactor trip to estimate the pre-trip average fuel temperatures and fuel-to-coolant heat transfer coefficients. Sub-assembly coolant mass flow and outlet temperature

Kwok K. WONG; Akira ENDOU

1999-01-01

32

Prediction of the resolution of capillary columns in different conditions of inlet pressure and temperature.  

PubMed

A procedure previously described for the prediction of the plate height of capillary columns operated at different inlet pressure of the carrier gas and at various column temperatures by using few retention data measured under isobaric conditions was modified and improved in order to permit the prediction of the retention times and of the peak widths at various heights. It is therefore possible to calculate the ratio, delta, between the peak width at different heights and the peak width at half height, whose value is used to predict the resolution at different height of two closely eluting peaks. It was found that the delta values do not depend on temperature and inlet pressure and are a characteristic of the used column; they can therefore be used in order to calculate the resolution in any temperature and inlet pressure condition. The method was used to predict the retention time, the peak width and the resolution of polar and non-polar compounds (alkanes, alkenes, chloroalkanes, alcohols, ketones) on capillary columns of different length and polarity by using as the starting data retention and width values measured in three isobaric runs only. PMID:14763748

Vezzani, S; Moretti, P; Castello, G; Travaini, G

2004-02-13

33

The effects of inlet temperature and pressure distortion on turbojet performance  

NASA Technical Reports Server (NTRS)

The effects on stability of steady-state, 180 degree extent circumferential distortions of inlet total temperature and pressure were experimentally determined for a turbojet engine. Results for both individual and combined temperature and pressure distortions are presented showing the losses incurred in stall pressure ratio and are compared with results predicted using a simplified parallel compressor model. The loss due to combined distortions was dependent upon the relative orientation between the low pressure and high temperature regions. Reasonable agreement was achieved between the predicted and observed loss in stall pressure ratio when based on a constant corrected speed relationship.

Braithwaite, W. M.; Graber, E. J., Jr.; Mehalic, C. M.

1973-01-01

34

Effect of Burst Temperature on Coolant Channel Restriction in Multirods Burst Tests  

Microsoft Academic Search

In order to study the effect of burst temperature on the coolant flow channel restriction, burst tests of fuel bundles were performed. Each bundle consisted of 49 rods (7×7 rods), and bursts were conducted in flowing steam. Burst temperature was changed by changing the internal gas pressure in rods. After the burst, the ballooning behavior of each rod and the

Satoru KAWASAKI; Masao HASHIMOTO; Takashi OTOMO; Teruo FURUTA; Hiroshi UETSUKA

1983-01-01

35

Computing Flows Of Coolants In Turbomachines  

NASA Technical Reports Server (NTRS)

Coolant Passage Flow (CPF) computer code developed to predict accurately coolant flow and heat transfer inside turbomachinery cooling passages (either radial or axial blading). Computes flow in one-inlet/one-outlet passage of any shape. Calculates rate of flow of coolant, temperature, pressure, velocity, and heat-transfer coefficients along passage. Integrates one-dimensional momentum and energy equations along defined flow path, taking into account change in area, addition or subtraction of mass, pumping, friction, and transfer of heat. Written in FORTRAN IV.

Meitner, P. L.

1994-01-01

36

Performance of a high-work, low-aspect-ratio turbine stator tested with a realistic inlet radial temperature gradient  

NASA Technical Reports Server (NTRS)

A 0.767-scale model of a turbine stator designed for the core of a high-bypass-ratio aircraft engine was tested with uniform inlet conditions and with an inlet radial temperature profile simulating engine conditions. The principal measurements were radial and circumferential surveys of stator-exit total temperature, total pressure, and flow angle. The stator-exit flow field was also computed by using a three-dimensional Navier-Stokes solver. Other than temperature, there were no apparent differences in performance due to the inlet conditions. The computed results compared quite well with the experimental results.

Stabe, Roy G.; Schwab, John R.

1991-01-01

37

Method of and apparatus for removing silicon from a high temperature sodium coolant  

DOEpatents

This patent discloses a method of and system for removing silicon from a high temperature liquid sodium coolant system for a nuclear reactor. The sodium is cooled to a temperature below the silicon saturation temperature and retained at such reduced temperature while inducing high turbulence into the sodium flow for promoting precipitation of silicon compounds and ultimate separation of silicon compound particles from the liquid sodium.

Yunker, W.H.; Christiansen, D.W.

1983-11-25

38

Effects of coolant parameters on steady state temperature distribution in phospheric-acid fuel cell electrode  

NASA Technical Reports Server (NTRS)

The influence of thermophysical properties and flow rate on the steady-state temperature distribution in a phosphoric-acid fuel cell electrode plate was experimentally investigated. An experimental setup that simulates the operating conditions prevailing in a phosphoric-acid fuel cell stack was used. The fuel cell cooling system utilized three types of coolants to remove excess heat generated in the cell electrode and to maintain a reasonably uniform temperature distribution in the electrode plate. The coolants used were water, engine oil, and air. These coolants were circulated at Reynolds number ranging from 1165 to 6165 for water; 3070 to 6864 for air; and 15 to 79 for oil. Experimental results are presented.

Alkasab, K. A.; Abdul-Aziz, A.

1991-01-01

39

Effect of coolant flow ejection on aerodynamic performance of low-aspect-ratio vanes. 2: Performance with coolant flow ejection at temperature ratios up to 2  

NASA Technical Reports Server (NTRS)

The aerodynamic performance of a 0.5 aspect ratio turbine vane configuration with coolant flow ejection was experimentally determined in a full annular cascade. The vanes were tested at a nominal mean section ideal critical velocity ratio of 0.890 over a range of primary to coolant total temperature ratio from 1.0 to 2.08 and a range of coolant to primary total pressure ratio from 1.0 to 1.4 which corresponded to coolant flows from 3.0 to 10.7 percent of the primary flow. The variations in primary and thermodynamic efficiency and exit flow conditions with circumferential and radial position were obtained.

Hass, J. E.; Kofskey, M. G.

1977-01-01

40

Numerical Research Engine Coolant Temperature and Flow Rate Effect on the Engine Cold Start  

Microsoft Academic Search

To study the influence of LNG fuel supply system on engine cooling system, ensure that the engine cold start performance, an AMESim based LNG fuel supply system simulation model with the key components of vaporizer was proposed. By analyzing the influence of the coolant temperature and flow rate on the phase transition of LNG, and worked out the ranges of

Ying Gao; Lei Zhang; Qing-yuan Dong; Da-wen Liu

2011-01-01

41

SNAP fuel temperature peaking with cusps in coolant channel  

Microsoft Academic Search

Reactor Fuel Elements--temperature peaking in SNAP due to surrounding rods; systems for nuclear auxiliary power (SNAP)--reactor fuel temperataure peaking due to surrounding fuel rods; temeprature--calculations of peaking of, in SNAP fuel due to sourround fuel rods.

Treuenfels

1963-01-01

42

Inlet nozzle assembly  

DOEpatents

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.

Christiansen, David W. (Kennewick, WA); Karnesky, Richard A. (Richland, WA); Precechtel, Donald R. (Richland, WA); Smith, Bob G. (Richland, WA); Knight, Ronald C. (Richland, WA)

1987-01-01

43

Inlet nozzle assembly  

DOEpatents

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.

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

1985-09-09

44

Transient heat transfer in channel flow with step change in inlet temperature  

NASA Astrophysics Data System (ADS)

A second-order accurate finite-difference scheme based on a modification of the upwind method for the classical wave equation is proposed for transient forced convection in laminar channel flow. Stability analysis is performed, and the modified equation is established. The problem involving a step change in inlet temperature is studied for both slug and parabolic flow inside a parallel-plate duct. The accuracy of the numerical scheme is examined by comparing the results to the exact solutions available for the case of slug flow. Numerical results are presented for the average flow temperature and local Nusselt number as a function of position along the channel at different times, and the thermal wave propagation phenomena are physically interpreted.

Cotta, R. M.; Ozisik, M. N.; McRae, D. S.

45

Barriers to the Application of High-Temperature Coolants in Hybrid Electric Vehicles  

Microsoft Academic Search

This study was performed by the Oak Ridge National Laboratory (ORNL) to identify practical approaches, technical barriers, and cost impacts to achieving high-temperature coolant operation for certain traction drive subassemblies and components of hybrid electric vehicles (HEV). HEVs are unique in their need for the cooling of certain dedicated-traction drive subassemblies\\/components that include the electric motor(s), generators(s), inverter, dc converter

Robert H Staunton; John S Hsu; Michael R Starke

2006-01-01

46

Effect of fuel-air ratio, inlet temperature, and exhaust pressure on detonation  

NASA Technical Reports Server (NTRS)

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.

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

1940-01-01

47

Effect of steady-state temperature distortion and combined distortion on inlet flow to a turbofan engine  

NASA Technical Reports Server (NTRS)

Flow angle, static pressure, total temperature and total pressure were measured in the inlet duct upstream of a turbofan engine operating with temperature distortion or combined pressure-temperature distortion. Such measurements are useful in the evaluation of analytical models of inlet distortion. A rotating gaseous-hydrogen burner and a circumferential 180 degrees-extent screen configuration mounted on a rotatable assembly generated the distortions. Reynolds number index was maintained at 0.5 and engine corrected low-rotor speeds were held at 6000 and 8600 rpm. The measurements showed that at the entrance to the engine, flow angle was largest in the hub region. As flow approached the engine, yaw angle (circumferential variation) increased and pitch angle (radial variation) decreased. The magnitude of static-pressure distortion measured along the inlet-duct and extended bullet nose walls increased exponentially as flow approached the engine.

Soeder, R. H.; Bobula, G. A.

1979-01-01

48

The high-temperature sodium coolant technology in nuclear power installations for hydrogen power engineering  

NASA Astrophysics Data System (ADS)

In the case of using high-temperature sodium-cooled nuclear power installations for obtaining hydrogen and for other innovative applications (gasification and fluidization of coal, deep petroleum refining, conversion of biomass into liquid fuel, in the chemical industry, metallurgy, food industry, etc.), the sources of hydrogen that enters from the reactor plant tertiary coolant circuit into its secondary coolant circuit have intensity two or three orders of magnitude higher than that of hydrogen sources at a nuclear power plant (NPP) equipped with a BN-600 reactor. Fundamentally new process solutions are proposed for such conditions. The main prerequisite for implementing them is that the hydrogen concentration in sodium coolant is a factor of 100-1000 higher than it is in modern NPPs taken in combination with removal of hydrogen from sodium by subjecting it to vacuum through membranes made of vanadium or niobium. Numerical investigations carried out using a diffusion model showed that, by varying such parameters as fuel rod cladding material, its thickness, and time of operation in developing the fuel rods for high-temperature nuclear power installations (HT NPIs) it is possible to exclude ingress of cesium into sodium through the sealed fuel rod cladding. However, if the fuel rod cladding loses its tightness, operation of the HT NPI with cesium in the sodium will be unavoidable. Under such conditions, measures must be taken for deeply purifying sodium from cesium in order to minimize the diffusion of cesium into the structural materials.

Kozlov, F. A.; Sorokin, A. P.; Alekseev, V. V.; Konovalov, M. A.

2014-05-01

49

Analytical Investigation of the Significance of Turbine-Inlet Temperature in High-Energy Rocket Turbodrive Applications  

NASA Technical Reports Server (NTRS)

The effect of turbine-inlet temperature on rocket gross weight was investigated for three high-energy long-range rockets in order to explore the desirability of turbine cooling in rocket turbodrive applications. Temperatures above and below the maximum that is permissible in uncooled turbines were included. Turbine bleed rate and stage number were considered as independent variables. The gross weight of the hydrogen-reactor system was more sensitive to changes in turbine-inlet temperature than either the hydrogen-oxygen or the hydrogen-fluorine systems. Gross weight of the hydrogen-reactor system could be reduced by 2.6 percent by the use of cooling and a turbine-inlet temperature of 3000 R. The reductions in the first stages of the hydrogen-oxygen and hydrogen-fluorine systems were 0.7 and 0.2 percent, respectively. The effect of turbine-inlet temperature on rocket gross weight was small because the resulting turbine weight and bleed rate variations were small. Since these small gains must be balanced against considerations of greater cost, weight, and complexity as well as lessened reliability with a system utilizing a cooled turbine, none of the systems investigated showed gains warranting the use of turbine cooling.

Rohlik, Harold E.

1959-01-01

50

Perturbations of reactor flow and inlet temperature in EBR-II for reactivity feedback validation  

SciTech Connect

A loss-of-flow (LOF) accident in current LMFBR safety studies is a total loss of pumping power coupled with a failure of the reactor shutdown system (RSS). Another accident of current interest is a loss-of-heat sink for the primary system without involving the RSS. Both types of transients are included in the Shutdown Heat Removal Tests (SHRT) presently being conducted in the Experimental Breeder Reactor II (EBR-II). An initial series of tests in EBR-II was successfully completed in June of 1984 which included investigation of the inherent reactivity feedback characteristics. In these tests, the reactor was perturbed at various power levels by independent variations in primary flow and reactor inlet temperature, and the reactor power and temperature response were measured. The reactor and balance of plant are extensively instrumented and measurements were recorded on a data acquisition system. Results show that the plant responds safely without any external control and confirm that the effects of reduced primary flow or reduced heat rejection are mitigated. More specifically, the data provide a basis for model validation and confidence in predictions of an upcoming series of unprotected LOF and loss-of-heat sink tests. In this paper, the pretest predictions, measured results, and posttest analyses are described in detail. Finally, the application of this feedback model to future EBR-II core loadings and implications for other LMFBR's are discussed.

Mohr, D.; Chang, L.K.

1985-01-01

51

Uniform and non-uniform inlet temperature of a vertical hot water jet injected into a rectangular tank  

Microsoft Academic Search

In most of real-world applications, such as the case of heat stores, inlet is not kept at a constant temperature but it may vary with time during charging process. In this paper, a vertical water jet injected into a rectangular storage tank is measured experimentally and simulated numerically. Two cases of study are considered; one is a hot water jet

M. F. El-Amin; S. Sun

2010-01-01

52

Temperature controller for a fluid cooled garment  

NASA Technical Reports Server (NTRS)

An automatic controller for controlling the inlet temperature of the coolant to a fluid cooled garment without requiring skin sensors is described. Temperature is controlled by the wearer's evaporative water loss rate.

Chambers, A. B.; Blackaby, J. R.; Billingham, J. (inventors)

1973-01-01

53

Two-dimensional inlet temperature profile attenuation in a turbine stage  

NASA Astrophysics Data System (ADS)

Experimental evidence has shown that hot streaks which are emitted from the combustors of gas turbines are often largely responsible for the burning of first stage turbine blades. Designers have attempted to counteract the effects of these hot streaks through the use of complex, internal and film cooling schemes. In an effort to increase understanding of the interaction mechanisms between combustor hot streaks and turbine blade heat transfer, a numerical investigation has been conducted to determine if a 2D solution procedure can accurately predict rotor airfoil surface heating for flows which include planar hot streaks. A 2D Navier-Stokes analysis is used to predict unsteady viscous flow through a 1-stator/1-rotor configuration with a planar hot streak introduced at the stator inlet. Comparison of the predicted results with a new experimental data set demonstrates that the 2D numerical procedure can be used to accurately predict time-averaged rotor pressure surface temperatures for flows which include planar hot streaks.

Dorney, Daniel J.; Davis, Roger J.; Sharma, Om P.

1991-06-01

54

Effects of core excess reactivity and coolant average temperature on maximum operable time of NIRR-1 miniature neutron source reactor  

Microsoft Academic Search

We appraised in this study the effects of core excess reactivity and average coolant temperature on the operable time of the Nigeria Research Reactor-1 (NIRR-1), which is a miniature neutron source reactor (MNSR). The duration of the reactor operating time and fluence depletion under different operation mode as well as change in core excess reactivity with temperature coefficient was investigated

Y. A. Ahmed; I. B. Mansir; I. Yusuf; G. I. Balogun; S. A. Jonah

2011-01-01

55

Inlet technology  

NASA Technical Reports Server (NTRS)

At hypersonic flight Mach numbers, particularly above Mo = 10, the inlet compression process is no longer adiabatic, real gas chemistry takes on extra importance, and the combined effects of entropy layer and viscous effects lead to highly nonuniform flow profile characteristics at the combustor entrance. Under such conditions, traditional inlet efficiency parameters can be unnecessarily cumbersome and/or lacking in the ability to appropriately characterize the inlet flow and to provide insight into propulsion system performance. Recent experience suggests that the use of inlet entropy increases inlet efficiency in hypersonic applications.

Kutschenreuter, Paul

1992-01-01

56

Simultaneous Measurements of Neutronic Noise with Fluctuation of Inlet Coolant Temperature and Vibration of a Control Rod at KUR.  

National Technical Information Service (NTIS)

Experiments on reactor noise were conducted at KUR. Depending on the operating condition of the reactor, the cause of the noise are classified into the following four types. (1) Zero-power noise source due to the branching process of fission neutrons and/...

I. Kimura S. An Y. Kimura Y. Oka

1976-01-01

57

Knock-limited performance of several internal coolants  

NASA Technical Reports Server (NTRS)

The effect of internal cooling on the knock-limited performance of an-f-28 fuel was investigated in a CFR engine, and the following internal coolants were used: (1) water, (2), methyl alcohol-water mixture, (3) ammonia-methyl alcohol-water mixture, (4) monomethylamine-water mixture, (5) dimethylamine-water mixture, and (6) trimethylamine-water mixture. Tests were run at inlet-air temperatures of 150 degrees and 250 degrees F. to indicate the temperature sensitivity of the internal-coolant solutions.

Bellman, Donald R; Evvard, John C

1945-01-01

58

Evaluation of High Temperature Tensile and Creep Properties of Light Water Reactor Coolant Piping Materials for Severe Accident Analyses  

Microsoft Academic Search

It has been pointed out that the reactor coolant system piping could fail prior to the meltthrough of the reactor pressure vessel in a high pressure sequence of pressurized water reactor severe accidents. In order to apply to the evaluation of the piping failure which influences the subsequent accident progression, models for the strength of piping materials at high temperatures

Yuhei HARADA; Yu MARUYAMA; Akio MAEDA; Eiichi CHINO; Hiroaki SHIBAZAKI; Tamotsu KUDO; Akihide HIDAKA; Kazuichiro HASHIMOTO; Jun SUGIMOTO

2000-01-01

59

Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel  

Microsoft Academic Search

High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950° C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides

A. F. Fauzia; A. Waris; Novitrian Novitrian

2010-01-01

60

The Effect of Inlet Temperature and Pressure on the Efficiency of Single-Stage Impulse Turbine Having a 13.2-Inch Pitch-Line Diameter Wheel  

NASA Technical Reports Server (NTRS)

Efficiency tests have been conducted on a single-stage impulse turbine having a 13.2-inch pitch-line diameter wheel and a cast nozzle diaphram over a range of turbine speeds from 3000 to 17,000 rpm, pressure ratios from 1.5 to 5.0, inlet total temperatures from 1200 deg to 2000 deg R, and inlet total pressures from 18 to 59 inches of mercury absolute. The effect of inlet temperature and pressure on turbine efficiency for constant pressure ration and blade-to-jet speed ration is correlated against a factor derived from the equation for Reynolds number. The degree of correlation indicates that the change in turbine efficiency with inlet temperature and [ressure for constant pressure ration and blade-to-jet speed ration is principally a Reynolds number effect.

Chanes, Ernest R.; Carman, L. Robert

1945-01-01

61

Computer code for predicting coolant flow and heat transfer in turbomachinery  

NASA Technical Reports Server (NTRS)

A computer code was developed to analyze any turbomachinery coolant flow path geometry that consist of a single flow passage with a unique inlet and exit. Flow can be bled off for tip-cap impingement cooling, and a flow bypass can be specified in which coolant flow is taken off at one point in the flow channel and reintroduced at a point farther downstream in the same channel. The user may either choose the coolant flow rate or let the program determine the flow rate from specified inlet and exit conditions. The computer code integrates the 1-D momentum and energy equations along a defined flow path and calculates the coolant's flow rate, temperature, pressure, and velocity and the heat transfer coefficients along the passage. The equations account for area change, mass addition or subtraction, pumping, friction, and heat transfer.

Meitner, Peter L.

1990-01-01

62

Transient response of a serpentine finned-tube cross-flow heat exchanger to a step change in inlet temperature  

SciTech Connect

An analysis of the thermal response of a finned-tube, liquid-to-gas cross-flow heat exchanger due to a step change in the liquid inlet temperature is performed. Closed-form solutions for the liquid and gas temperatures as functions of space and time are obtained via the Laplace transform technique for both small and large arguments of the modified Bessel function of the first kind. Using four physically important dimensionless parameters, the response of the liquid and average gas outlet temperatures are studied and presented in the time domain. The analysis is extended to a single-row serpentine coil geometry by accounting for U-tube bends. Using a typical heat exchanger geometry, the effects of the tube bends are shown to be significant. Relevant applications include automotive and HVAC heat exchangers and systems.

Abdallah, S.; Rooke, S. [Univ. of Akron, OH (United States). Dept. of Mechanical Engineering

1997-07-01

63

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)

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.

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

1973-01-01

64

Development of fast-burn combustion with elevated coolant temperatures for natural gas engines. Final report, May 1985-May 1990  

SciTech Connect

The overall objective of the work was to improve the state of the art in the gas fired spark ignited engine for use in a cogeneration system. Four characteristics were enhanced for cogeneration, namely, Low Pressure Gas Induction, Improved Shaft Thermal Efficiency, Low NOx Emissions, and Increased Jacket Coolant Temperature. Using Taguchi methods and statistical design of experiment methodologies, an engine design evolved that exhibited: The ability to run satisfactorily on supply gas pressure as low as 1.5 psig (goal: 1 psig); A brake specific fuel consumption as low as 6950 Btu/hp-hr (36.6% thermal efficiency) at 2 gm/hp-hr NOx (goal: 7000 acceptable, 6800 excellent with NOx no more than 2 gm/hp-hr); A jacket water coolant system (with oil cooler on the same circuit) temperature of 225 F (goal); and The ability to burn gas with Methane Number as low as 67 (goal).

Bruch, K.L.; Dennis, J.W.

1990-09-01

65

Analysis of metal temperature and coolant flow with a thermal-barrier coating on a full-coverage-film-cooled turbine vane  

NASA Technical Reports Server (NTRS)

The potential benefits of combining full-coverage film cooling with a thermal-barrier coating were investigated analytically for sections on the suction and pressure sides a high-temperature, high-pressure turbine vane. Metal and ceramic coating temperatures were calculated as a function of coating thickness and coolant flow. With a thermal-barrier coating, the coolant flows required for the chosen sections were half those of an uncoated design, and the metal outer temperatures were simultaneously reduced by over 111 K (200 F). For comparison, transpiration cooling was also investigated. Full-coverage film cooling of a coated vane required more coolant flow than did transpiration cooling.

Meitner, P. L.

1978-01-01

66

Measurement of Core Coolant Flow Velocities in PWRs Using Temperature: Neutron Noise Cross Correlation.  

National Technical Information Service (NTIS)

To study the relationship between the time delay inferred from this phase angle and core coolant flow velocities, noise measurements were performed at the Loss of Fluid Test Facility (LOFT) reactor and at a commercial PWR. In-core, self-powered neutron de...

F. J. Sweeney B. R. Upadhyaya

1982-01-01

67

Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement  

NASA Technical Reports Server (NTRS)

Data obtained from an extensive investigation of the cooling characteristics of four multicylinder, liquid-cooled engines have been analyzed and a correlation of both the cylinder-head temperatures and the coolant heat rejections with the primary engine and coolant variables was obtained. The method of correlation was previously developed by the NACA from an analysis of the cooling processes involved in a liquid-cooled-engine cylinder and is based on the theory of nonboiling, forced-convection heat transfer. The data correlated included engine power outputs from 275 to 1860 brake horsepower; coolant flows from 50 to 320 gallons per minute; coolants varying in composition from 100 percent water to 97 percent ethylene glycol and 3 percent water; and ranges of engine speed, manifold pressure, carburetor-air temperature, fuel-air ratio, exhaust-gas pressure, ignition timing, and coolant temperature. The effect on engine cooling of scale formation on the coolant passages of the engine and of boiling of the coolant under various operating conditions is also discussed.

Lundin, Bruce T; Povolny, John H; Chelko, Louis J

1949-01-01

68

Physical properties of heavy liquid-metal coolants in a wide temperature range  

Microsoft Academic Search

The pulse-phase method, the gamma-attenuation method and the method of dumping oscillation of a crucible with a melt were used for measuring the velocity of sound, the density and the kinematic viscosity of a set of liquid-metal coolants for perspective nuclear reactors. There are liquid gallium, indium, tin, lead, bismuth and lead-bismuth eutectic alloy among the melts investigated. The accuracy

P. Popel; S. Stankus; A. Mozgovoy; R. Khairulin; M. Pokrasin; D. Yagodin; N. Konstantinova; A. Borisenko; M. Guzachev

2011-01-01

69

Influences of calcium oxide content in marine fuel oil on emission characteristics of marine furnaces under varying humidity and temperature of the inlet air.  

PubMed

A marine furnace made of stainless steel. combined with an automatic small-size oil-fired burner, was used to experimentally investigate the influences of calcium oxide content in fuel oil on the combustion and emission characteristics under varying temperatures and humidity of the inlet air. Marine fuel oil generally contains various extents of metallic oxides such as CaO, Fe2O3, V2O5, etc which might affect its burning properties. In this study, an air-conditioner was used to adjust the humidity and temperatures of the inlet air to preset values prior to entering the burner. The adjusted inlet air atomized the marine diesel oil A containing a calcium oxide compound, to form a heterogeneous reactant mixture. The reactant mixture was thereafter ignited by a high-voltage electrode in the burner and burned within the marine furnace. The probes of a gas analyzer, H2S analyzer and a K-type thermocouple were inserted into the radial positions of the furnace through the eight rectangular slots which were cut in the upper side of the furnace. The experimental results showed that an increase of either humidity or temperature of the inlet air caused the promotion of the reaction rate of the fuel. The existence of calcium oxide compound in the diesel fuel also facilitated the oxidation reaction in the combustion chamber. The addition of CaO in the diesel fuel under the conditions of higher temperature or higher relative humidity of the inlet air produced the following: higher concentrations of CO2, SO2, and H2S emissions, an increased burning efficiency, a lowered O2 level, production of excess air and NOx emissions as well as a lower thermal loss and a lower burning gas temperature, as compared with the conditions of a lower temperature or a lower humidity of the inlet air. In addition, the burning of diesel fuel with added CaO compound caused a large variation in the burning efficiency, thermal loss, plus CO2, O2, and excess air emissions between the conditions of higher temperature/higher humidity and lower temperature/lower humidity inlet air compared with no CaO addition in the fuel. Moreover, the burning efficiency and the concentrations of excess air and O2 emissions increased, while the thermal loss, burning gas temperature and H2S, SO2, NOx, and CO2 emissions decreased with the increase of the axial distance from the measured location to the burner nozzle. PMID:15030157

Lin, Cherng-Yuan; Chen, Wei-Cheng

2004-01-01

70

Solar receiver protection means and method for loss of coolant flow  

DOEpatents

An apparatus and method for preventing a solar receiver (12) utilizing a flowing coolant liquid for removing heat energy therefrom from overheating after a loss of coolant flow. Solar energy is directed to the solar receiver (12) by a plurality of reflectors (16) which rotate so that they direct solar energy to the receiver (12) as the earth rotates. The apparatus disclosed includes a first storage tank (30) for containing a first predetermined volume of the coolant and a first predetermined volume of gas at a first predetermined pressure. The first storage tank (30) includes an inlet and outlet through which the coolant can enter and exit. The apparatus also includes a second storage tank (34) for containing a second predetermined volume of the coolant and a second predetermined volume of the gas at a second predetermined pressure, the second storage tank (34) having an inlet through which the coolant can enter. The first and second storage tanks (30) and (34) are in fluid communication with each other through the solar receiver (12). The first and second predetermined coolant volumes, the first and second gas volumes, and the first and second predetermined pressures are chosen so that a predetermined volume of the coolant liquid at a predetermined rate profile will flow from the first storage tank (30) through the solar receiver (12) and into the second storage tank (34). Thus, in the event of a power failure so that coolant flow ceases and the solar reflectors (16) stop rotating, a flow rate maintained by the pressure differential between the first and second storage tanks (30) and (34) will be sufficient to maintain the coolant in the receiver (12) below a predetermined upper temperature until the solar reflectors (16) become defocused with respect to the solar receiver (12) due to the earth's rotation.

Glasgow, Lyle E. (Westlake Village, CA)

1983-01-01

71

Solar receiver protection means and method for loss of coolant flow  

DOEpatents

An apparatus and method are disclosed for preventing a solar receiver utilizing a flowing coolant liquid for removing heat energy therefrom from overheating after a loss of coolant flow. Solar energy is directed to the solar receiver by a plurality of reflectors which rotate so that they direct solar energy to the receiver as the earth rotates. The apparatus disclosed includes a first storage tank for containing a first predetermined volume of the coolant and a first predetermined volume of gas at a first predetermined pressure. The first storage tank includes an inlet and outlet through which the coolant can enter and exit. The apparatus also includes a second storage tank for containing a second predetermined volume of the coolant and a second predetermined volume of the gas at a second predetermined pressure, the second storage tank having an inlet through which the coolant can enter. The first and second storage tanks are in fluid communication with each other through the solar receiver. The first and second predetermined coolant volumes, the first and second gas volumes, and the first and second predetermined pressures are chosen so that a predetermined volume of the coolant liquid at a predetermined rate profile will flow from the first storage tank through the solar receiver and into the second storage tank. Thus, in the event of a power failure so that coolant flow ceases and the solar reflectors stop rotating, a flow rate maintained by the pressure differential between the first and second storage tanks will be sufficient to maintain the coolant in the receiver below a predetermined upper temperature until the solar reflectors become defocused with respect to the solar receiver due to the earth's rotation.

Glasgow, L.E.

1980-11-24

72

Effect of moderate inlet temperatures in ultra-high-pressure homogenization treatments on physicochemical and sensory characteristics of milk.  

PubMed

The effect of ultra-high-pressure homogenization (UHPH) on raw whole milk (3.5% fat) was evaluated to obtain processing conditions for the sterilization of milk. Ultra-high-pressure homogenization treatments of 200 and 300MPa at inlet temperatures (Ti) of 55, 65, 75, and 85°C were compared with a UHT treatment (138°C for 4s) in terms of microbial inactivation, particle size and microstructure, viscosity, color, buffering capacity, ethanol stability, propensity to proteolysis, and sensory evaluation. The UHPH-treated milks presented a high level of microbial reduction, under the detection limit, for treatments at 300MPa with Ti of 55, 65, 75, and 85°C, and at 200MPa with Ti=85°C, and few survivors in milks treated at 200MPa with Ti of 55, 65, and 75°C. Furthermore, UHPH treatments performed at 300MPa with Ti=75 and 85°C produced sterile milk after sample incubation (30 and 45°C), obtaining similar or better characteristics than UHT milk in color, particle size, viscosity, buffer capacity, ethanol stability, propensity to protein hydrolysis, and lower scores in sensory evaluation for cooked flavor. PMID:24342690

Amador-Espejo, G G; Suàrez-Berencia, A; Juan, B; Bárcenas, M E; Trujillo, A J

2014-02-01

73

FORTRAN program for calculating coolant flow and metal temperatures of a full-coverage-film-cooled vane or blade  

NASA Technical Reports Server (NTRS)

A computer program that calculates the coolant flow and the metal temperatures of a full-coverage-film-cooled vane or blade was developed. The analysis was based on compressible, one-dimensional fluid flow and on one-dimensional heat transfer and treats the vane or blade shell as a porous wall. The calculated temperatures are average values for the shell outer-surface area associated with each film-cooling hole row. A thermal-barrier coating may be specified on the shell outer surface, and centrifugal effects can be included for blade calculations. The program is written in FORTRAN 4 and is operational on a UNIVAC 1100/42 computer. The method of analysis, the program input, the program output, and two sample problems are provided.

Meitner, P. L.

1978-01-01

74

Investigation of the Influence of Cooling Water Inlet Temperature on Characteristics and Ammonia Charging Quantity of Ammonia-Water Absorption Refrigerator  

NASA Astrophysics Data System (ADS)

For purposes such as freezing and ice accumulation which require temperatures below 0 degrees, ammonia-water absorption refrigerator is being looked at once again. If used for these purpose, it is usually driven all through the year. In this case, cooling water inlet temperature which greatly influences absorption cycle changes very widely. So in such conditions, it is hoped to be driven high efficiently. And ammonia's charging quantity is required as small as possible on account of poisonous. But when it driven all through the year, ammonia charging quantity influences the efficiency greatly. So this research aims to clarify the ammonia charging quantity with which ammonia-water absorption refrigerator can be driven high efficiently. So static simulation model was made. By using this tool, we investigated the influence of cooling water inlet temperature on COP, solution concentration. As a result, minimum ammonia charging quantity with which ammonia water absorption refrigerator can be driven was obtained.

Takei, Toshitaka; Saito, Kiyoshi; Kawai, Sunao

75

Cooling Characteristics of the V-1650-7 Engine. 1; Coolant-Flow Distribution, Cylinder Temperatures, and Heat Rejections at Typical Operating Conditions  

NASA Technical Reports Server (NTRS)

An investigation was conducted to determine the coolant-flow distribu tion, the cylinder temperatures, and the heat rejections of the V-165 0-7 engine . The tests were run a t several power levels varying from minimum fuel consumption to war emergency power and at each power l evel the coolant flows corresponded to the extremes of those likely t o be encountered in typical airplane installations, A mixture of 30-p ercent ethylene glycol and 70-percent water was used as the coolant. The temperature of each cylinder was measured between the exhaust val ves, between the intake valves, in the center of the head, on the exh aust-valve guide, at the top of the barrel on the exhaust side, and o n each exhaust spark-plug gasket. For an increase in engine power fro m 628 to approximately 1700 brake horsepower the average temperature for the cylinder heads between the exhaust valves increased from 437 deg to 517 deg F, the engine coolant heat rejection increased from 12 ,600 to 22,700 Btu. per minute, the oil heat rejection increased from 1030 to 4600 Btu per minute, and the aftercooler-coolant heat reject ion increased from 450 to 3500 Btu -per minute.

Povolny, John H.; Bogdan, Louis J.

1947-01-01

76

Gas-leaking fuel elements number and fission gas product coolant volumetric activities assessment in the VVER-440 nuclear power plant  

NASA Astrophysics Data System (ADS)

In a nuclear power plant it is required to monitor continuously the number of gas-leaking fuel elements and the contamination level of the primary coolant by fission gas products. It is proposed to use the radiation monitoring system equipped with the computer technics provided with the suitable program package for fulfilment this requirements. The input data to start up the program consists of the 88Kr volumetric activity measured by the radiation monitoring system and three actual technological parameters: coolant temperature at inlet, thermal power and coolant flow rate.

Szuta, Marcin

1992-07-01

77

The effect of operating temperature on open, multimegawatt space power systems  

SciTech Connect

This study addresses reactor powered and combustion powered multimegawatt, burst mode, space power systems to evaluate the effect turbine inlet temperature will have on their performance and mass. Both systems will provide power to space based antiballistic missile weapons that require hydrogen for cooling, and both use this hydrogen coolant as a working fluid or as a fuel for power generation. The quantity of hydrogen needed for weapon cooling increases as the weapon's cooling load increases and as weapon coolant outlet temperature decreases. Also, the hydrogen needed by the turbines in both power systems increases as turbine inlet temperature decreases. When weapon cooling loads are above 40% to 50% of weapon power and weapon coolant outlet temperature is below 300 K to 400 K, the weapon needs more hydrogen than the turbine in either the reactor or combustion powered systems using turbine inlet temperatures consistent with current material technology. There is therefore very little system mass reduction to be gained by operating a burst mode power system at a turbine inlet temperature above present material temperature limits unless the weapon's cooling load is below 40% to 50% or coolant outlet temperature is above 300 K to 400 K. Furthermore, the combustion system's mass increases as turbine inlet temperature increases because oxygen inventory increases with increased turbine inlet temperature.

Edenburn, M.W.

1987-01-01

78

Experimental and theoretical comparison of fuel temperature and bulk coolant characteristics in the Oregon State TRIGA ® reactor during steady state operation  

Microsoft Academic Search

In September of 2008 Oregon State University (OSU) completed its core conversion analysis as part of the Reduced Enrichment for Research and Test Reactors (RERTR) Program. Experimental bulk coolant temperatures were collected in various locations throughout the Oregon State TRIGA® Reactor (OSTR) core in order to supplement the validity of the numerical thermal hydraulic results produced in RELAP5-3D Version 2.4.2.Axial

W. R. Marcum; B. G. Woods; S. R. Reese

2010-01-01

79

PIPING FOR COOLANT WATER IS INSTALLED INSIDE REACTOR STRUCTURE PRIOR ...  

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

PIPING FOR COOLANT WATER IS INSTALLED INSIDE REACTOR STRUCTURE PRIOR TO EMBEDMENT IN CONCRETE. HIGHER PIPE IS INLET; THE OTHER, THE OUTLET LOOP. INLET PIPE WILL CONNECT TO TOP SECTION OF REACTOR VESSEL. INL NEGATIVE NO. 1287. Unknown Photographer, 1/18/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

80

Thermal stratification potential in rocket engine coolant channels  

NASA Technical Reports Server (NTRS)

The potential for rocket engine coolant channel flow stratification was computationally studied. A conjugate, 3-D, conduction/advection analysis code (SINDA/FLUINT) was used. Core fluid temperatures were predicted to vary by over 360 K across the coolant channel, at the throat section, indicating that the conventional assumption of a fully mixed fluid may be extremely inaccurate. Because of the thermal stratification of the fluid, the walls exposed to the rocket engine exhaust gases will be hotter than an assumption of full mixing would imply. In this analysis, wall temperatures were 160 K hotter in the turbulent mixing case than in the full mixing case. The discrepancy between the full mixing and turbulent mixing analyses increased with increasing heat transfer. Both analysis methods predicted identical channel resistances at the coolant inlet, but in the stratified analysis the thermal resistance was negligible. The implications are significant. Neglect of thermal stratification could lead to underpredictions in nozzle wall temperatures. Even worse, testing at subscale conditions may be inadequate for modeling conditions that would exist in a full scale engine.

Kacynski, Kenneth J.

1992-01-01

81

Turbomachine injection nozzle including a coolant delivery system  

DOEpatents

An injection nozzle for a turbomachine includes a main body having a first end portion that extends to a second end portion defining an exterior wall having an outer surface. A plurality of fluid delivery tubes extend through the main body. Each of the plurality of fluid delivery tubes includes a first fluid inlet for receiving a first fluid, a second fluid inlet for receiving a second fluid and an outlet. The injection nozzle further includes a coolant delivery system arranged within the main body. The coolant delivery system guides a coolant along at least one of a portion of the exterior wall and around the plurality of fluid delivery tubes.

Zuo, Baifang (Simpsonville, SC)

2012-02-14

82

Subsonic Scarf Inlets Investigated  

NASA Technical Reports Server (NTRS)

A computational investigation is underway at the NASA Glenn Research Center to determine the aerodynamic performance of subsonic scarf inlets. These inlets are characterized as being longer over the lower portion of the inlet, as shown in the preceding figure. One of the key variables being investigated in the research is the circumferential extent of the longer portion of the inlet. It shows two specific geometries that are being examined: one in which the length of the inlet transitions from long-to-short over the full 180 deg. from bottom to top, and a second in which the length transitions over 67.5 deg.

Abbott, John M.

2005-01-01

83

Afterburner Performance of Circular V-Gutters and a Sector of Parallel V-Gutters for a Range of Inlet Temperatures to 1255 K (1800 F)  

NASA Technical Reports Server (NTRS)

Combustion tests of two V-gutter types were conducted in a 19.25-in. diameter duct using vitiated air. Fuel spraybars were mounted in line with the V-gutters. Combustor length was set by flame-quench water sprays which were part of a calorimeter for measuring combustion efficiency. Although the levels of performance of the parallel and circular array afterburners were different, the trends with geometry variations were consistent. Therefore, parallel arrays can be used for evaluating V-gutter geometry effects on combustion performance. For both arrays, the highest inlet temperature produced combustion efficiencies near 100 percent. A 5-in. spraybar - to - V-gutter spacing gave higher efficiency and better lean blowout performance than a spacing twice as large. Gutter durability was good.

Brandstetter, J. Robert; Reck, Gregory M.

1973-01-01

84

Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel  

SciTech Connect

High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950 deg. C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of {sup 235}U enrichment.

Fauzia, A. F.; Waris, A.; Novitrian [Bosscha Laboratory, Department of Physics, Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, INDONESIA Jl. Ganesa 10 Bandung 40132 (Indonesia)

2010-06-22

85

Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel  

NASA Astrophysics Data System (ADS)

High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950° C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of 235U enrichment.

Fauzia, A. F.; Waris, A.; Novitrian, Novitrian

2010-06-01

86

Preparation and properties of inhalable nanocomposite particles: effects of the size, weight ratio of the primary nanoparticles in nanocomposite particles and temperature at a spray-dryer inlet upon properties of nanocomposite particles.  

PubMed

Nanoparticles are expected to be applicable to inhalation as carrier but there exist disadvantages because of their size. Their deposition dose to the lung will be small. To overcome this problem and utilize nanoparticles for inhalation, we have prepared nanocomposite particles as drug carriers targeting lungs. The nanocomposite particles are prepared as drug-loaded nanoparticles-additive complex to reach deep in the lungs and to be decomposed into nanoparticles when they deposit into lung. In this study, we examined the effect of preparation condition--inlet temperature, size of primary nanoparticles and weight ratio of primary nanoparticles--on the property of nanocomposite particles. When the size of primary nanoparticles was 400 nm and inlet temperature was 90 degrees C, only the nanocomposite particles containing between 45 and 55% of primary nanoparticles could be decomposed into nanoparticles in water. On the other hand, when the inlet temperature was 80 degrees C, nanocomposite particles were decomposed into nanoparticles independent of the weight ratio of primary nanoparticles. Also, the aerodynamic diameter of the nanocomposite particles was between 1.5 and 2.5 microm, independent of the weight ratio of primary nanoparticles. When the size of primary nanoparticles was 200 nm and inlet temperature was 70 degrees C, nanocomposite particles were decomposed into nanoparticles independent of the weight ratio of primary nanoparticles. Also, the aerodynamic diameters of them were almost 2.0 microm independent of the weight ratio of primary nanoparticles. When the nanocomposite particles containing nanoparticles with the size of 200 nm are prepared at 80 degrees C, no decomposition into nanoparticles was observed in water. Fine particle values, FPF, of the nanocomposite particles were not affected by the weight ratio of primary nanoparticles when they were prepared at optimum inlet temperature. PMID:18343097

Tomoda, Keishiro; Ohkoshi, Takumi; Nakajima, Takehisa; Makino, Kimiko

2008-06-15

87

Autoignition in a premixing-prevaporizing fuel duct using 3 different fuel injection systems at inlet air temperatures to 1250 K  

NASA Astrophysics Data System (ADS)

Conditions were determined in a continuous-flow, premixing-prevaporizing duct at which autoignition occurred. Test conditions were representative of an advanced, regenerative-cycle, automotive gas turbine. The test conditions inlet air temperatures from 600 to 1250 K (a vitiated preheater was used), pressures from 170 to 600 kPa, air velocities of 10 to 30 m/sec, equivalence ratios from 0.3 to 1.0, mixing lengths from 10 to 60 cm, and residence times of 2 to 100 ms. The fuel was diesel number 2. The duct was insulated and had an inside diameter of 12 cm. Three different fuel injection systems were used: One was a single simplex pressure atomizer, and the other two were multiple-source injectors. The data obtained with the simplex and one of the multiple-source injectors agreed satisfactorily with the references and correlated with an Arrenhius expression. The data obtained with the other multiple source injector, which used multiple cones to improve the fuel-air distribution, did not correlate well with residence time.

Tacina, R. R.

1983-05-01

88

Autoignition in a premixing-prevaporizing fuel duct using 3 different fuel injection systems at inlet air temperatures to 1250 K  

NASA Technical Reports Server (NTRS)

Conditions were determined in a continuous-flow, premixing-prevaporizing duct at which autoignition occurred. Test conditions were representative of an advanced, regenerative-cycle, automotive gas turbine. The test conditions inlet air temperatures from 600 to 1250 K (a vitiated preheater was used), pressures from 170 to 600 kPa, air velocities of 10 to 30 m/sec, equivalence ratios from 0.3 to 1.0, mixing lengths from 10 to 60 cm, and residence times of 2 to 100 ms. The fuel was diesel number 2. The duct was insulated and had an inside diameter of 12 cm. Three different fuel injection systems were used: One was a single simplex pressure atomizer, and the other two were multiple-source injectors. The data obtained with the simplex and one of the multiple-source injectors agreed satisfactorily with the references and correlated with an Arrenhius expression. The data obtained with the other multiple source injector, which used multiple cones to improve the fuel-air distribution, did not correlate well with residence time.

Tacina, R. R.

1983-01-01

89

A liquid cooled garment temperature controller based on sweat rate  

NASA Technical Reports Server (NTRS)

An automatic controller for liquid cooled space suits is reported that utilizes human sweat rate as the primary input signal. The controller is so designed that the coolant inlet temperature is inversely proportional to the subject's latent heat loss as evidenced by evaporative water loss.

Chambers, A. B.; Blackaby, J. R.

1972-01-01

90

Core Dynamics Analysis for Reactivity Insertion and Loss of Coolant Flow Tests Using the High Temperature Engineering Test Reactor  

Microsoft Academic Search

Safety demonstration tests using the High Temperature Engineering Test Reactor (HTTR) are in progress to verify its inherent safety features and improve the safety technology and design methodology for High-temperature Gas-cooled Reactors (HTGRs). The reactivity insertion test is one of the safety demonstration tests for the HTTR. This test simulates the rapid increase in the reactor power by withdrawing the

Kuniyoshi Takamatsu; Shigeaki Nakagawa; Tetsuaki Takeda

2008-01-01

91

Fluid inlet distributor  

SciTech Connect

A fluid inlet distributor is described for a fluid treating vessel adapted to contain a body of oil and a body of a liquid of different gravity from the oil and immiscible therewith. The distributor consists of a chamber provided with at least one row of orifices disposed horizontally along a longitudinal side of the chamber, fluid inlet means to the chamber, and at least one conduit joined to the chamber in fluid communication therewith and extending downwardly from the chamber. The conduits are open at their bottom ends and the chamber being otherwise closed.

Watson, F.D.

1986-09-02

92

Water inlet blowdown  

NASA Astrophysics Data System (ADS)

A new blowdown system was developed for cleaning debris from the inlet grill of waterjet propulsion system on Boeing hydrofoil boats. A system was required to work with existing waterjet ducts which are open ended. The new blowdown system consists of an abrupt discharge of high pressure compressed air amidst the water inlet duct. It utilizes the open end of the propulsor discharge nozzle as a safety valve. Feasibility was proven by semi-steady state equations and was confirmed by full scale testing. A system was developed and installed and is now fully operational.

Timar, T.

1981-09-01

93

Analysis of heat transfer in a porous cooled wall with variable pressure and temperature along the coolant exit boundary  

NASA Technical Reports Server (NTRS)

Fluid from a reservior at constant pressure and temperature is forced through a porous wall of uniform thickness. The boundary through which the fluid exits has specified variations in pressure and temperature along it in one direction so that the flow and heat transfer are two-dimensional. The local fluid and matrix temperatures are assumed to be equal and therefore a single energy equation governs the temperature distribution within the wall. The solution is obtained by transforming this energy equation into potential plane coordinates, which results in a separable equation. A technique yielding an integral equation is used to adapt the general solution so that it satisfies the variable-pressure boundary condition. Analytical expressions are given for the normal exit velocity and heat flux along the exit boundary. Illustrative examples are carried out which indicate to what extent the solution is locally one-dimensional.

Siegel, R.; Goldstein, M. E.

1972-01-01

94

High alpha Inlets.  

National Technical Information Service (NTIS)

The high alpha inlet research effort at Lewis is part of the High Alpha Technology Program (HATP) within NASA. A key goal of HATP is to develop concepts that provide a high level of control and maneuverability for high performance aircraft at low subsonic...

R. R. Burley B. H. Anderson C. F. Smith G. J. Harloff

1991-01-01

95

Aerodynamic performance of scarf inlets  

NASA Technical Reports Server (NTRS)

A scarf inlet is characterized by having a longer lower lip than upper lip leading to both aerodynamic and acoustic advantages. Aerodynamically, a scarf inlet has higher angle of attack capability and is less likely to ingest foreign objects while the aircraft is on the ground. Acoustically, a scarf inlet provides for reduced inlet radiated noise levels below the engine as a result of upward reflection and refraction of inlet radiated noise. Results of a wind tunnel test program are presented which illustrate the aerodynamic performance of two different scarf inlet designs. Based on these results, scarf inlet performance is summarized in a way to illustrate the advantages and limitations of a scarf inlet compared to an axisymmetric inlet.

Abbott, J. M.

1979-01-01

96

EFFECT OF HIGH-PRESSURE COOLANT JET ON GRINDING TEMPERATURE, CHIP AND SURFACE ROUGHNESS IN GRINDING AISI1040 STEEL  

Microsoft Academic Search

Grinding can be described as a multi-tooth metal cutting operation in which material is generally removed by shearing and ploughing in the form of micro sized chips by the abrasive grits of the grinding wheel. As a result, high temperature is produced in the grinding zone due to large negative rake and high cutting speed of the grinding wheel. Suitable

N. R. Dhar; A. T. Siddiqui; M. H. Rashid

2006-01-01

97

Nanofluids: Future Industrial Coolants  

NASA Astrophysics Data System (ADS)

Nanofluids have emerged as a major area of research due to significant increase found in their thermal conductivity compared to the base fluids like Water, Ethylene Glycol, Toluene, etc. The enhanced transport properties of nanofluids and heat transfer efficiency have given them an edge over micro to macro sized particle suspensions. These fluids find great applications in thermal management as industrial coolants and various biomedical applications including cancer therapy. Major mechanism appears to be layering of liquid molecules at the solid-particle surface to form an interfacial nanolayer. This paper describes the dependence of effective thermal conductivity of nanofluids on nanoparticle concentration and transport properties of interfacial layer. We have studied the role of interfacial layer and nanoparticle Al2O3 concentration to the effective thermal conductivity of Al2O3/Water based nanofluid. Effect of temperature and pressure has also been investigated. Estimated values are found to match excellently with the available experimental data.

Arora, Sakshi; Srivastava, Sunita

2011-12-01

98

Atmospheric pressure sample inlet for mass spectrometers  

NASA Astrophysics Data System (ADS)

An inlet for a mass spectrometer has been developed for direct sampling of gases over a wide range of pressure (1-760 Torr). The sample inlet is composed of two small orifices that form a pressure reduction region. These orifices are used to limit the flow of sample gas into the mass spectrometer. The pressure inside the pressure reduction region is regulated by a needle valve and a vacuum pump. The flow of gas through the orifices is viscous. The inlet is made of stainless steel and operated at high temperature to prevent surface adsorption and corrosion. Its adaptability to a wide range of pressures is very useful for monitoring process gases during manufacturing processes of microelectronic devices. This inlet can be used for effluent gas analysis at 760 Torr as well as for in situ monitoring of the semiconductor equipment at pressures less than 5 Torr. The inlet provides a fast response to changes in the constituents of gas samples without memory effects. The sample inlet has been tested extensively in the laboratory as well as in field environments.

Dheandhanoo, Seksan; Ciotti, Ralph J.; Ketkar, Suhas N.

2000-12-01

99

Influence of coolant injector configuration on film cooling effectiveness for gaseous and liquid film coolants  

NASA Astrophysics Data System (ADS)

An experimental investigation is conducted to bring out the effects of coolant injector configuration on film cooling effectiveness, film cooled length and film uniformity associated with gaseous and liquid coolants. A series of measurements are performed using hot air as the core gas and gaseous nitrogen and water as the film coolants in a cylindrical test section simulating a thrust chamber. Straight and compound angle injection at two different configurations of 30°-10° and 45°-10° are investigated for the gaseous coolant. Tangential injection at 30° and compound angle injection at 30°-10° are examined for the liquid coolant. The analysis is based on measurements of the film-cooling effectiveness and film uniformity downstream of the injection location at different blowing ratios. Measured results showed that compound angle configuration leads to lower far-field effectiveness and shorter film length compared to tangential injection in the case of liquid film cooling. For similar injector configurations, effectiveness along the stream wise direction showed flat characteristics initially for the liquid coolant, while it was continuously dropping for the gaseous coolant. For liquid coolant, deviations in temperature around the circumference are very low near the injection point, but increases to higher values for regions away from the coolant injection locations. The study brings out the existance of an optimum gaseous film coolant injector configuration for which the effectiveness is maximum.

Shine, S. R.; Sunil Kumar, S.; Suresh, B. N.

2012-05-01

100

A Tale of Two Inlets: Tidal Currents at Two Adjacent Inlets in the Indian River Lagoon  

NASA Astrophysics Data System (ADS)

The tidal currents and hydrography at two adjacent inlets of the Indian River Lagoon estuary (Florida) were recently measured using a personal watercraft-based coastal profiling system. Although the two inlets—Sebastian Inlet and Port Canaveral Inlet—are separated by only 60 km, their characteristics and dynamics are quite unique. While Sebastian Inlet is a shallow (~4 m), curved inlet with a free connection to the estuary, Port Canaveral Inlet is dominated by a deep (~13 m), straight ship channel and has limited connectivity to the Banana River through a sector gate lock. Underway measurements of tidal currents were obtained using a bottom tracking acoustic Doppler current profiler; vertical casts of hydrography were obtained with a conductivity-temperature-depth profiling instrument; and continuous underway measurements of surface water hydrography were made using a Portable SeaKeeper system. Survey transects were performed to elucidate the along-channel variability of tidal flows, which appears to be significant in the presence of channel curvature. Ebb and flood tidal currents in Sebastian Inlet routinely exceeded 2.5 m/s from the surface to the bed, and an appreciable phase lag exists between tidal stage and current magnitude. The tidal currents at Port Canaveral Inlet were much smaller (~0.2 m/s) and appeared to be sensitive to meteorological forcing during the study period. Although the lagoon has free connections to the ocean 145 km to the north and 45 km to the south, Sebastian Inlet likely drains much of the lagoon to its north, an area of ~550 sq. km.

Webb, B. M.; Weaver, R. J.

2012-12-01

101

Nuclear reactor coolant pump impeller/shaft assembly  

SciTech Connect

A pump is described comprising: (a) a casing having an inlet and an outlet in fluid communication for circulating fluid coolant through the pump; (b) a shaft positioned in the casing; (c) an impeller nut connected to the shaft; (d) a lockbolt fixedly connecting the impeller nut relative to the shaft; (e) passageway means with first and second ends for directing fluid from the lockbolt to the shaft; (f) first conduit means formed in the impeller nut in fluid communication with the first end of the passageway means and the inlet of the casing; and (g) second conduit means formed in the impeller nut in fluid communication with the second end of the passageway means and the outlet of the casing. A portion of the fluid coolant circulating through the inlet of the casing is pumped through the first conduit means, through the passageway means, out the second conduit means and into the outlet of the casing.

Jenkins, L.S.

1987-09-01

102

Machine coolant waste reduction by optimizing coolant life. Project summary  

SciTech Connect

The project was designed to study the following: A specific water-soluble coolant (Blasocut 2000 Universal) in use with a variety of machines, tools, and materials; Coolant maintenance practices associated with three types of machines; Health effects of use and handling of recycled coolant; Handling practices for chips and waste coolant; Chip/coolant separation; and Oil/water separation.

Pallansch, J.

1995-08-01

103

CFD analyses of coolant channel flowfields  

NASA Technical Reports Server (NTRS)

The flowfield characteristics in a rocket engine coolant channels are analyzed by means of a numerical model. The channels are characterized by large length to diameter ratios, high Reynolds numbers, and asymmetrical heating. At representative flow conditions, the channel length is approximately twice the hydraulic entrance length so fully developed conditions are reached. The supercritical hydrogen coolant introduces strong property variations that have a major influence on the developing flow and the resulting heat transfer. Comparisons of constant and variable property solutions show substantial differences. The density variation accelerates the fluid in the channels increasing the pressure drop without an accompanying increase in heat flux. Analyses of the inlet configuration suggest that side entry from a manifold can affect the development of the velocity profile because of vortices generated as the flow enters the channel.

Yagley, J. A.; Feng, J.; Merkle, Charles L.

1993-01-01

104

Inlet shear heating in elastohydrodynamic lubrication.  

NASA Technical Reports Server (NTRS)

In elastohydrodynamic lubrication, the oil film thickness of rollers is controlled by the rate at which the oil is drawn into the conjunction of the disks by the moving surfaces of the rollers. The theory often assumes isothermal conditions in the inlet, although it can be shown that the maximum shear rate often exceeds 1,000,000 per sec, even in pure rolling. A theoretical analysis is presented for the oil temperature rise in the inlet of rollers, and the result is applied to predict the consequent film thickness. It is found that thermal effects on film thickness are only negligible at low rolling speeds. A comparison with experiment supports the conclusion that the thinning of the film thickness below that predicted by isothermal theory is substantially explained by inlet shear heating of the lubricant.

Greenwood, J. A.; Kauzlarich, J. J.

1972-01-01

105

Inlets, ducts, and nozzles  

NASA Technical Reports Server (NTRS)

The internal fluid mechanics research program in inlets, ducts, and nozzles consists of a balanced effort between the development of computational tools (both parabolized Navier-Stokes and full Navier-Stokes) and the conduct of experimental research. The experiments are designed to better understand the fluid flow physics, to develop new or improved flow models, and to provide benchmark quality data sets for validation of the computational methods. The inlet, duct, and nozzle research program is described according to three major classifications of flow phenomena: (1) highly 3-D flow fields; (2) shock-boundary-layer interactions; and (3) shear layer control. Specific examples of current and future elements of the research program are described for each of these phenomenon. In particular, the highly 3-D flow field phenomenon is highlighted by describing the computational and experimental research program in transition ducts having a round-to-rectangular area variation. In the case of shock-boundary-layer interactions, the specific details of research for normal shock-boundary-layer interactions are described. For shear layer control, research in vortex generators and the use of aerodynamic excitation for enhancement of the jet mixing process are described.

Abbott, John M.; Anderson, Bernhard H.; Rice, Edward J.

1990-01-01

106

Flow boiling test of GDP replacement coolants  

SciTech Connect

The tests were part of the CFC replacement program to identify and test alternate coolants to replace CFC-114 being used in the uranium enrichment plants at Paducah and Portsmouth. The coolants tested, C{sub 4}F{sub 10} and C{sub 4}F{sub 8}, were selected based on their compatibility with the uranium hexafluoride process gas and how well the boiling temperature and vapor pressure matched that of CFC-114. However, the heat of vaporization of both coolants is lower than that of CFC-114 requiring larger coolant mass flow than CFC-114 to remove the same amount of heat. The vapor pressure of these coolants is higher than CFC-114 within the cascade operational range, and each coolant can be used as a replacement coolant with some limitation at 3,300 hp operation. The results of the CFC-114/C{sub 4}F{sub 10} mixture tests show boiling heat transfer coefficient degraded to a minimum value with about 25% C{sub 4}F{sub 10} weight mixture in CFC-114 and the degree of degradation is about 20% from that of CFC-114 boiling heat transfer coefficient. This report consists of the final reports from Cudo Technologies, Ltd.

Park, S.H. [comp.

1995-08-01

107

Microstructural analysis of MTR fuel plates damaged by a coolant flow blockage  

NASA Astrophysics Data System (ADS)

In 1975, as a result of a blockage of the coolant inlet flow, two plates of a fuel element of the BR2 reactor of the Belgian Nuclear Research Centre (SCK•CEN) were partially melted. The fuel element consisted of Al-clad plates with 90% 235U enriched UAl x fuel dispersed in an Al matrix. The element had accumulated a burn up of 21% 235U before it was removed from the reactor. Recently, the damaged fuel plates were sent to the hot laboratory for detailed PIE. Microstructural changes and associated temperature markers were used to identify several stages in the progression to fuel melting. It was found that the temperature in the center of the fuel plate had increased above 900-950 °C before the reactor was scrammed. In view of the limited availability of such datasets, the results of this microstructural analysis provide valuable input in the analysis of accident scenarios for research reactors.

Leenaers, A.; Joppen, F.; Van den Berghe, S.

2009-10-01

108

Engine coolant testing: Second symposium  

Microsoft Academic Search

This book presents the papers given at a symposium on the performance testing of engine coolants. Topics considered at the symposium included test methods for the development of supplemental additives for heavy-duty diesel engine coolants, a review of factors influencing coolant-metal interfaces in engines, corrosivity, and the evaluation of engine coolants by electrochemical methods.

Beal

1984-01-01

109

Engine coolant testing: Fourth volume  

Microsoft Academic Search

The 25 papers in this proceeding are arranged under the following topical sections: Organic acid inhibitor technology; Test methods; Heavy-duty coolant technology; Engine coolant recycling technology; Engine coolant characteristics and quality; and Engine coolant service and disposal. Papers within scope have been processed separately for inclusion on the data base.

Beal

1999-01-01

110

Nuclear reactor coolant transport system  

Microsoft Academic Search

A system for transporting reactor coolant in nuclear reactors using a liquid coolant is described. The system diverts a portion of the output from the main circulating pump in the nuclear reactor primary flow system and introduces this diverted coolant back into the system upstream of the main circulating pump. This diverted coolant compensates for any pressure drop which may

Mangus

1980-01-01

111

Analysis of the SSME HPOTP bearing inlet cavity  

NASA Technical Reports Server (NTRS)

Analysis of the flow in the Space Shuttle Main Engine (SSME) high pressure oxygen turbopump (HPOTP) bearing no. 1 inlet cavity was completed in support of return-to-flight. With the incorporation of several design changes in the Phase 2 turbopump, rotordynamic stability of the pumps was enhanced, but the durability and life of the LOX-cooled bearings has decreased. During the post-Challenger SSME recertification, the causes of limited bearing durability were investigated. One topic addressed was the flow environment upstream of the pump-end bearing and the effect of seal exit swirl and a cavity anti-vortex rib on the bearing environment and life. The objective is to define the hydrodynamic environment upstream of the pump-end bearing and determine the effect of seal exit swirl and the anti-vortex rib on bearing inlet swirl. The problem was posed as an axisymmetric cavity flow with the computational domain extending from the seal exit to the bearing inlet. This domain was discretized with 22800 grid points. Boundary conditions were obtained from a 1-D model of the SSME coolant path. The inlet Mach number was 0.19 and the problem was solved with the CMINT code utilizing the Briley-McDonald/Beam-Warming algorithm with preconditioning to speed convergence at low Mach numbers. Three parametric cases with inlet swirl of 50 percent shaft speed (labyrinth seal), 20 percent shaft speed (damping seal), and no inlet swirl were considered. Computational results indicate large vortical flow structures in the cavity, with the labyrinth, damping, and no-swirl cases yielding bearing inlet swirl rates of 14, 10, and 9 percent of shaft speed, respectively. When these results were used as input to the SHABRETH bearing model, limited durability could not be explained by these small differences in swirl. Also, based on these results, a proposed design change for the cavity anti-vortex rib was not implemented by the SSME chief engineer.

Mcconnaughey, P. K.

1989-01-01

112

Aerodynamic Performance of Scarf Inlets.  

National Technical Information Service (NTIS)

A scarf inlet is characterized by having a longer lower lip than upper lip leading to both aerodynamic and acoustic advantages. Aerodynamically, a scarf inlet has higher angle of attack capability and is less likely to ingest foreign objects while the air...

J. M. Abbott

1979-01-01

113

Ribbed Coolant Liners for Combustion Chambers  

NASA Technical Reports Server (NTRS)

Coolant-carrying liner for combustion chambers runs cooler and tolerates high-temperature excursions without burning out. Hot gases flowing through core prevented by liner from damaging shell. Concept applicable to such high-temperature chambers as rocket pre-burners, turbojet cans, stationary-turbine combustors, oil burners, and high-pressure chemical reactors.

Wagner, W. R.

1984-01-01

114

Jet Impingement Quenching: Effect of Coolant Accumulation  

NASA Astrophysics Data System (ADS)

During quenching of wide steel plates with impinging water jets in the accelerated cooling section of a plate mill, the coolant accumulates over the plate. In this study, the effect of coolant accumulation on the heat transfer rate during jet impingement quenching has been investigated. In these experiments, the coolant accumulates over the impingement surface of the test specimen within a volume created by assembling a ceramic tube length around the test specimen. The quenching rate with and without the accumulation of coolant are compared. The propagation of the wetting front is decelerated due to the accumulation of coolant. The reduction in the jet impingement momentum as it passes through the accumulated layer of coolant and the obstruction to the radial outflow of the released vapor by the ceramic tube are the likely reasons for this observation. The maximum heat flux value, analogous to the critical heat flux condition of steady state pool boiling, decreases due to accumulation, but the corresponding temperature shows little dependence on accumulation. This study contributes to further the understanding of the jet impingement quenching process.

Karwa, Nitin; Stephan, Peter

2012-11-01

115

Radiant energy receiver having improved coolant flow control means  

DOEpatents

An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

Hinterberger, H.

1980-10-29

116

Effects of optimized and sub-optimum two degree of freedom lining tolerances on modeled inlet acoustic attenuation and Normal incidence impedance measurement at elevated temperatures  

NASA Astrophysics Data System (ADS)

This work first investigates the effect of manufacturing tolerances on realized attenuation for two degree-of-freedom linings with the use of lining models and finite element duct propagation codes. Acoustic linings were created for two turbofan engines that optimize attenuation at takeoff/sideline and approach conditions. Lining physical and geometric parameters were set, which best meet the optimum impedance requirements at two target frequencies. Similar linings were created to investigate sub-optimum designs. Variations of these parameters representing realistic manufacturing tolerances were used to systematically examine the effect on installed impedance and predicted attenuation. Attenuation at sideline and approach conditions was found to be sensitive to manufacturing tolerances around optimum conditions. The results of the study are case dependent; however the analysis scheme presented provides a method for cost-benefit analysis of manufacturing processes. In a second study, an impedance tube, with an associated data analysis method, was developed and analyzed for temperature uncertainties that allowed the measurement of impedance of acoustic samples at elevated temperatures. This impedance measurement method was validated at room temperature by comparing the results with predicted impedance from empirically based impedance models and with impedance measurements in a standard traversing microphone impedance tube. Impedance for four samples was measured at elevated temperatures, and the results were compared to room temperature measurements. For two of the samples, the impedances measured at elevated temperatures were compared to the results of extensions of room temperature empirical models, confirming the trend of the results of the elevated temperature measurements.

Burd, David R.

117

Safety and environmental aspects of organic coolants for fusion facilities  

NASA Astrophysics Data System (ADS)

Organic coolants, such as OS-84, offer unique advantages for fusion reactor applications. These advantages are with respect to both reactor operation and safety. The key operational advantage is a coolant that can provide high temperature (350-400°C) at modest pressure (2-4 MPa). These temperatures are needed for conditioning the plasma-facing components and, in reactors, for achieving high thermodynamic conversion efficiencies (>40%). The key safety advantage of organic coolants is the low vapor pressure, which significantly reduces the containment pressurization transient (relative to water) following a loss of coolant event. Also, from an occupational dose viewpoint, organic coolants significantly reduce corrosion and erosion inside the cooling system and consequently reduce the quantity of activation products deposited in cooling system equipment. On the negative side, organic coolants undergo both pyrolytic and radiolytic decomposition, and are flammable. While the decomposition rate can be minimized by coolant system design (by reducing coolant inventories exposed to neutron flux and to high temperatures), decomposition products are formed and these degrade the coolant properties. Both heavy compounds and light gases are produced from the decomposition process, and both must be removed to maintain adequate coolant properties. As these hydrocarbons may become tritiated by permeation, or activated through impurities, their disposal could create an environmental concern. Because of this potential waste disposal problem, consideration has been given to the recycling of both the light and heavy products, thereby reducing the quantity of waste to be disposed. Preliminary assessments made for various fusion reactor designs, including ITER, suggest that it is feasible to use organic coolants for several applications. These applications range from first wall and blanket coolant (the most demanding with respect to decomposition), to shield and vacuum vessel cooling, to an intermediate cooling loop removing heat from a liquid metal loop and transferring it to a steam generator or heat exchanger.

Natalizio, A.; Hollies, R. E.; Gierszewski, P.

1993-06-01

118

Development of an Engine Coolant Thermostatic/Pressure Switch.  

National Technical Information Service (NTIS)

Military vehicle engine cooling systems are frequently pressurized in order to raise the operating temperature of the coolant above the ambient boiling temperature. System pressure can be lost due to a defective radiator cap or any other pressure leak. Un...

R. L. Englund J. E. Englund R. L. Champoux

1991-01-01

119

Nuclear-Radiation-Actuated Valve for Increasing Coolant Flow to Blanket).  

National Technical Information Service (NTIS)

The present invention relates to a breeder reactor blanket fuel assembly coolant system valve which increases coolant flow to the blanket fuel assembly to minimize long-term temperature increases caused by fission of fissile fuel created from fertile fuel...

D. W. Christiansen D. P. Schively

1982-01-01

120

A Heated Tube Facility for Rocket Coolant Channel Research  

NASA Technical Reports Server (NTRS)

The capabilities of a heated tube facility used for testing rocket engine coolant channels at the NASA Lewis Research Center are presented. The facility uses high current, low voltage power supplies to resistively heat a test section to outer wall temperatures as high as 730 C (1350 F). Liquid or gaseous nitrogen, gaseous helium, or combustible liquids can be used as the test section coolant. The test section is enclosed in a vacuum chamber to minimize heat loss to the surrounding system. Test section geometry, size, and material; coolant properties; and heating levels can be varied to generate heat transfer and coolant performance data bases.

Green, James M.; Pease, Gary M.; Meyer, Michael L.

1995-01-01

121

Primary Coolant Conductivity Study.  

National Technical Information Service (NTIS)

The AF NETF, a 10 MW water-cooled research reactor, monitors the conductivity of its coolant to detect erosion/corrosion of its structural systems and fuel element failure. When a gradual increase in this conductivity sent it above the defined limit, a st...

J. W. Baker A. N. Fasano L. B. Hary F. B. Buoni

1967-01-01

122

Environmentally Friendly Coolant System  

SciTech Connect

Energy reduction through the use of the EFCS is most improved by increasing machining productivity. Throughout testing, nearly all machining operations demonstrated less land wear on the tooling when using the EFCS which results in increased tool life. These increases in tool life advance into increased productivity. Increasing productivity reduces cycle times and therefore reduces energy consumption. The average energy savings by using the EFCS in these machining operations with these materials is 9%. The advantage for end milling stays with flood coolant by about 6.6% due to its use of a low pressure pump. Face milling and drilling are both about 17.5% less energy consumption with the EFCS than flood coolant. One additional result of using the EFCS is improved surface finish. Certain machining operations using the EFCS result in a smoother surface finish. Applications where finishing operations are required will be able to take advantage of the improved finish by reducing the time or possibly eliminating completely one or more finishing steps and thereby reduce their energy consumption. Some machining operations on specific materials do not show advantages for the EFCS when compared to flood coolants. More information about these processes will be presented later in the report. A key point to remember though, is that even with equivalent results, the EFCS is replacing petroleum based coolants whose production produces GHG emissions and create unsafe work environments.

David Jackson Principal Investigator

2011-11-08

123

Automatic coolant flow control device for a nuclear reactor assembly  

DOEpatents

A device which controls coolant flow through a nuclear reactor assembly comprises a baffle means at the exit end of said assembly having a plurality of orifices, and a bimetallic member in operative relation to the baffle means such that at increased temperatures said bimetallic member deforms to unblock some of said orifices and allow increased coolant flow therethrough.

Hutter, E.

1984-01-27

124

Automatic coolant flow control device for a nuclear reactor assembly  

DOEpatents

A device which controls coolant flow through a nuclear reactor assembly comprises a baffle means at the exit end of said assembly having a plurality of orifices, and a bimetallic member in operative relation to the baffle means such that at increased temperatures said bimetallic member deforms to unblock some of said orifices and allow increased coolant flow therethrough.

Hutter, Ernest (Wilmette, IL) [Wilmette, IL

1986-01-01

125

Summary of investigations of engine response to distorted inlet conditions  

NASA Technical Reports Server (NTRS)

A survey is presented of experimental and analytical experience of the NASA Lewis Research Center in engine response to inlet temperature and pressure distortions. Results of experimental investigations and analytical modeling are reviewed together with a description of the hardware and the techniques employed. Distortion devices successfully simulated inlet distortion, and knowledge was gained on compression system response to different types of distortion. A list of NASA research references is included.

Biesiadny, Thomas J.; Braithwaite, Willis M.; Soeder, Ronald H.; Abdelwahab, Mahmood

1987-01-01

126

Computation of Space Shuttle high-pressure cryogenic turbopump ball bearing two-phase coolant flow  

NASA Technical Reports Server (NTRS)

A homogeneous two-phase fluid flow model, implemented in a three-dimensional Navier-Stokes solver using computational fluid dynamics methodology is described. The application of the model to the analysis of the pump-end bearing coolant flow of the high-pressure oxygen turbopump of the Space Shuttle main engine is studied. Results indicate large boiling zones and hot spots near the ball/race contact points. The extent of the phase change of the liquid oxygen coolant flow due to the frictional and viscous heat fluxes near the contact areas has been investigated for the given inlet conditions of the coolant.

Chen, Yen-Sen

1990-01-01

127

Investigation of "6X" Scramjet Inlet Configurations  

NASA Technical Reports Server (NTRS)

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.

Alter, Stephen J.

2012-01-01

128

A Study of Effects of Coolants on Heat Transfer Capability of On-chip Cooling with CNT Micro-fin Architectures by Using CFD Simulation  

Microsoft Academic Search

The two-dimensional computational fluid dynamics (CFD) simulations have been done for a series of material parameters of coolants in this paper. The influences of thermal conductivity, density, specific heat and viscosity on cooling have been obtained in the case studies. The pressure drop between the inlet and outlet of the cooling device is dependent on coolant's density and viscosity. Consequently,

Yi Fan; Xiaolong Zhong; Johan Liu; Teng Wang; Yan Zhang; Zhaonian Cheng

2007-01-01

129

Performance study for inlet installations  

NASA Technical Reports Server (NTRS)

A conceptual design trade study was conducted by McDonnell Aircraft Company (MCAIR) and NASA LARC PAB to determine the impact of inlet design features incorporated for reduced detectability on inlet performance, weight, and cost, for both fighter and attack-type aircraft. Quality Function Deployment (QFD) techniques were used to prioritize trade study issues, and select 'best' air induction system configurations for each of two notional aircraft, the Multi-Role Fighter (MRF) and the Advanced Medium Attack (AMA) bomber. Database deficiencies discovered in the trade study process were identified, and technology roadmaps were developed to address these deficiencies. Finally, two high speed inlet wind tunnel model concepts were developed for follow-on wind tunnel investigations.

Bingaman, Donald C.

1992-01-01

130

CFD analyses of coolant channel flowfields  

NASA Technical Reports Server (NTRS)

The flowfield characteristics in rocket engine coolant channels are analyzed by means of a numerical model. The channels are characterized by large length to diameter ratios, high Reynolds numbers, and asymmetrical heating. At representative flow conditions, the channel length is approximately twice the hydraulic entrance length so that fully developed conditions would be reached for a constant property fluid. For the supercritical hydrogen that is used as the coolant, the strong property variations create significant secondary flows in the cross-plane which have a major influence on the flow and the resulting heat transfer. Comparison of constant and variable property solutions show substantial differences. In addition, the property variations prevent fully developed flow. The density variation accelerates the fluid in the channels increasing the pressure drop without an accompanying increase in heat flux. Analyses of the inlet configuration suggest that side entry from a manifold can affect the development of the velocity profile because of vortices generated as the flow enters the channel. Current work is focused on studying the effects of channel bifurcation on the flow field and the heat transfer characteristics.

Yagley, Jennifer A.; Feng, Jinzhang; Merkle, Charles L.

1993-01-01

131

Loss-of-coolant accident test series test loc 3 experiment predictions. [PWR  

Microsoft Academic Search

The Loss of Coolant Accident (LOCA) Test Series being conducted in the Power Burst Facility (PBF) at the Idaho National Engineering Laboratory has been designed to provide data for the development and the assessment of fuel behavior computer codes used to predict the response of light water reactors during a hypothetical break in the cold-leg inlet or hot-leg outlet of

T. R. Yackle; P. H. Klink; J. W. Spore; L. K. Sepold; D. W. Nigg

1979-01-01

132

Behavior of primary coolant pump shaft seals during station blackout conditions  

Microsoft Academic Search

An assessment is made of the ability of typical Reactor Coolant Pump (RCP) Shaft Seals to withstand the conditions predicted for a station blackout (loss of all alternating current power) at a nuclear power station. Several factors are identified that are key to seal stability including inlet fluid conditions, pressure downstream of the seal, and geometrical details of the seal

R. C. Hill; D. B. Rhodes

1986-01-01

133

CFD Modeling of Turbulent Duct Flows for Coolant Channel Analysis  

NASA Technical Reports Server (NTRS)

The design of modern liquid rocket engines requires the analysis of chamber coolant channels to maximize the heat transfer while minimizing the coolant flow. Coolant channels often do not remain at a constant cross section or at uniform curvature. New designs require higher aspect ratio coolant channels than previously used. To broaden the analysis capability and to complement standard analysis tools an investigation on the accuracy of CFD predictions for coolant channel flow has been initiated. Validation of CFD capabilities for coolant channel analysis will enhance the capabilities for optimizing design parameters without resorting to extensive experimental testing. The eventual goal is to use CFD to determine the flow fields of unique coolant channel designs and therefore determine critical heat transfer coefficients. In this presentation the accuracy of a particular CFD code is evaluated for turbulent flows. The first part of the presentation is a comparison of numerical results to existing cold flow data for square curved ducts (NASA CR-3367, 'Measurements of Laminar and Turbulent Flow in a Curved Duct with Thin Inlet Boundary Layers'). The results of this comparison show good agreement with the relatively coarse experimental data. The second part of the presentation compares two cases of higher aspect ratio channels (AR=2.5,10) to show changes in axial and secondary flow strength. These cases match experimental work presently in progress and will be used for future validation. The comparison shows increased secondary flow strength of the higher aspect ratio case due to the change in radius of curvature. The presentation includes a test case with a heated wall to demonstrate the program's capability. The presentation concludes with an outline of the procedure used to validate the CFD code for future design analysis.

Ungewitter, Ronald J.; Chan, Daniel C.

1993-01-01

134

Design and Analysis Tools for Supersonic Inlets  

NASA Technical Reports Server (NTRS)

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.

Slater, John W.; Folk, Thomas C.

2009-01-01

135

On-site profiling and speciation of polycyclic aromatic hydrocarbons at manufactured gas plant sites by a high temperature transfer line, membrane inlet probe coupled to a photoionization detector and gas chromatography/mass spectrometer  

SciTech Connect

A new high temperature transfer line, membrane inlet probe (HTTL-MIP) coupled to a photoionization detector (PID) and gas chromatograph/mass spectrometer (GC/MS) was used to rapidly profile and speciate polycyclic aromatic hydrocarbons (PAH) in the subsurface. PID signals were in agreement with GC/MS results. Correlation coefficients of 0.92 and 0.99 were obtained for discrete and composite samples collected from the same exact location. Continuous probe advancement with PID detection found coal tar, a dense nonaqueous phase liquid, in soil channels and saturated media. When samples were collected conventionally, split, solvent extracted, and analyzed in the field and confirmation laboratory, GC/MS measurement precision and accuracy were indistinguishable; despite the fact the field laboratory produced data five times faster than the laboratory using standard EPA methods. No false positive/negatives were found. Based on these findings, increased confidence in site conceptual models should be obtained, since PID response indicated total PAH presence/absence in 'real-time', while GC/MS provided information as to which PAH was present and at what concentration. Incorporation of this tool into a dynamic workplan will provide more data at less cost enabling environmental scientists, engineers, and regulators to better understand coal tar migration and its impact on human health and the environment. 24 refs., 3 figs., 4 tabs.

Thomas Considine; Albert Robbat Jr. [Tufts University, Medford, MA (United States). Chemistry Department, Center for Field Analytical Studies and Technology

2008-02-15

136

Method for removing cesium from a nuclear reactor coolant  

DOEpatents

A method of and system for removing cesium from a liquid metal reactor coolant including a carbon packing trap in the primary coolant system for absorbing a major portion of the radioactive cesium from the coolant flowing therethrough at a reduced temperature. A regeneration subloop system having a secondary carbon packing trap is selectively connected to the primary system for isolating the main trap therefrom and connecting it to the regeneration system. Increasing the temperature of the sodium flowing through the primary trap diffuses a portion of the cesium

Colburn, Richard P. (Pasco, WA)

1986-01-01

137

Reactor coolant pump flywheel  

DOEpatents

A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

2013-11-26

138

Inlet Flow Valve Engine Analyses  

NASA Technical Reports Server (NTRS)

Pratt&Whitney, under Task Order 13 of the NASA Large Engine Technology (LET) Contract, conducted a study to determine the operating characteristics, performance and weights of Inlet Flow Valve (IFV) propulsion concepts for a Mach 2.4 High Speed Civil Transport (HSCT).

Champagne, G. A.

2004-01-01

139

Oscillating-Coolant Heat Exchanger  

NASA Technical Reports Server (NTRS)

Devices useful in situations in which heat pipes inadequate. Conceptual oscillating-coolant heat exchanger (OCHEX) transports heat from its hotter portions to cooler portions. Heat transported by oscillation of single-phase fluid, called primary coolant, in coolant passages. No time-averaged flow in tubes, so either heat removed from end reservoirs on every cycle or heat removed indirectly by cooling sides of channels with another coolant. Devices include leading-edge cooling devices in hypersonic aircraft and "frost-free" heat exchangers. Also used in any situation in which heat pipe used and in other situations in which heat pipes not usable.

Scotti, Stephen J.; Blosser, Max L.; Camarda, Charles J.

1992-01-01

140

IPAC-Inlet Performance Analysis Code  

NASA Technical Reports Server (NTRS)

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.

Barnhart, Paul J.

1997-01-01

141

High-speed inlet research program and supporting analyses  

NASA Technical Reports Server (NTRS)

A Mach 5 cruise aircraft was studied in a joint program effort. The propulsion system chosen for this aircraft was an over-under turbojet/ramjet system. The ramjet portion of the inlet is to be tested in NASA Lewis' 10 x 10 SWT. Goals of the test program are to obtain performance data and bleed requirements, and also to obtain analysis code validation data. Supporting analysis of the inlet using a three-dimensional Navier-Stokes code (PEPSIS) indicates that sidewall shock/boundary layer interactions cause large separated regions in the corners underneath the cowl. Such separations generally lead to inlet unstart, and are thus a major concern. As a result of the analysis, additional bleed regions were added to the inlet model sidewalls and cowl to control separations in the corners. A two-dimensional analysis incorporating bleed on the ramp is also presented. Supporting experiments for the Mach 5 programs were conducted in the Lewis' 1 x 1 SWT. A small-scale model representing the inlet geometry up to the ramp shoulder and cowl lip was tested to verify the accelerator plate test technique and to obtain data on flow migration in the ramp and sidewall boundary layers. Another study explored several ramp bleed configurations to control boundary layer separations in that region. Design of a two-dimensional Mach 5 cruise inlet represents several major challenges including multimode operation and dual flow, high temperatures, and three-dimensional airflow effects.

Coltrin, Robert E.

1987-01-01

142

Flow Table Study of Cook Inlet, Alaska.  

National Technical Information Service (NTIS)

Complex flow patterns in upper Cook Inlet in the vicinity of the Port of Anchorage re simulated using a flow table. Initially, two idealized models of the inlet were constructed with terraced layers representing the bathymetry. Encouraging test results pr...

S. A. Hughes G. Pizzo

2003-01-01

143

An approach to optimum subsonic inlet design  

NASA Technical Reports Server (NTRS)

Inlet operating requirements are compared with estimated inlet separation characteristics to identify the most critical inlet operating condition. This critical condition is taken to be the design point and is defined by the values of inlet mass flow, free-stream velocity and inlet angle of attack. Optimum flow distributions on the inlet surface were determined to be a high, flat top Mach number distribution on the inlet lip to turn the flow quickly into the inlet and a flat bottom skin-friction distribution on the diffuser wall to diffuse the flow rapidly and efficiently to the velocity required at the fan face. These optimum distributions are then modified to achieve other desirable flow characteristics. Example applications are given.

Luidens, R. W.; Stockman, N. O.; Diedrich, J. H.

1978-01-01

144

Cook Inlet Beluga Age and Growth.  

National Technical Information Service (NTIS)

The Cook Inlet beluga population declined 47% from 1994 to 1998. This decline has highlighted the need to gather and understand basic life history information of the population. Teeth from harvested and stranded Cook Inlet belugas, collected from 1992 to ...

D. J. Vos

2003-01-01

145

Hydraulics and Stability of Tidal Inlets.  

National Technical Information Service (NTIS)

This report presents a summary of several of the important basic developments pertaining to analysis of the hydraulics and related stability of tidal inlets. The original inlet stability concept proposed by Escoffier is extended in light of recent work. T...

F. F. Escoffier

1977-01-01

146

Generic Hypersonic Inlet Module Analysis  

NASA Technical Reports Server (NTRS)

A computational study associated with an internal inlet drag analysis was performed for a generic hypersonic inlet module. The purpose of this study was to determine the feasibility of computing the internal drag force for a generic scramjet engine module using computational methods. The computational study consisted of obtaining two-dimensional (2D) and three-dimensional (3D) computational fluid dynamics (CFD) solutions using the Euler and parabolized Navier-Stokes (PNS) equations. The solution accuracy was assessed by comparisons with experimental pitot pressure data. The CFD analysis indicates that the 3D PNS solutions show the best agreement with experimental pitot pressure data. The internal inlet drag analysis consisted of obtaining drag force predictions based on experimental data and 3D CFD solutions. A comparative assessment of each of the drag prediction methods is made and the sensitivity of CFD drag values to computational procedures is documented. The analysis indicates that the CFD drag predictions are highly sensitive to the computational procedure used.

Cockrell, Chares E., Jr.; Huebner, Lawrence D.

2004-01-01

147

Combustion engine with additional air inlet valve  

Microsoft Academic Search

A combustion engine equipped with an additional air-inlet means and a control arrangement for closing and opening the inlet is described that results in more efficient combustion and favorable limitation of carbon monoxide and nitrogen oxide formation. The scope of the invention covers cylindrical, lifting, or rotary piston arrangements. The additional air inlet and its associated cam controlling device allow

Gospodar

1974-01-01

148

Transmission geometry laserspray ionization vacuum using an atmospheric pressure inlet.  

PubMed

This represents the first report of laserspray ionization vacuum (LSIV) with operation directly from atmospheric pressure for use in mass spectrometry. Two different types of electrospray ionization source inlets were converted to LSIV sources by equipping the entrance of the atmospheric pressure inlet aperture with a customized cone that is sealed with a removable glass plate holding the matrix/analyte sample. A laser aligned in transmission geometry (at 180° relative to the inlet) ablates the matrix/analyte sample deposited on the vacuum side of the glass slide. Laser ablation from vacuum requires lower inlet temperature relative to laser ablation at atmospheric pressure. However, higher inlet temperature is required for high-mass analytes, for example, ?-chymotrypsinogen (25.6 kDa). Labile compounds such as gangliosides and cardiolipins are detected in the negative ion mode directly from mouse brain tissue as intact doubly deprotonated ions. Multiple charging enhances the ion mobility spectrometry separation of ions derived from complex tissue samples. PMID:24896880

Lutomski, Corinne A; El-Baba, Tarick J; Inutan, Ellen D; Manly, Cory D; Wager-Miller, James; Mackie, Ken; Trimpin, Sarah

2014-07-01

149

Coolant passage heat transfer with rotation  

NASA Technical Reports Server (NTRS)

In current and advanced gas turbine engines, increased speeds, pressures and temperatures are used to reduce specific fuel consumption and increase thrust/weight ratios. Hence, the turbine airfoils are subjected to increased heat loads escalating the cooling requirements to satisfy life goals. The efficient use of cooling air requires that the details of local geometry and flow conditions be adequately modeled to predict local heat loads and the corresponding heat transfer coefficients. The objective of this program is to develop a heat transfer and pressure drop data base, computational fluid dynamic techniques and correlations for multi-pass rotating coolant passages with and without flow turbulators. The experimental effort is focused on the simulation of configurations and conditions expected in the blades of advanced aircraft high pressure turbines. With the use of this data base, the effects of Coriolis and buoyancy forces on the coolant side flow can be included in the design of turbine blades.

Hajek, T. J.; Wagner, J.; Johnson, B. V.

1986-01-01

150

Atmospheric effects on the inlet system of the YF-12 aircraft  

NASA Technical Reports Server (NTRS)

Flights of a YF-12 airplane were performed over a wide range of operating conditions so that detailed comparisons could be made with data from tests on scale models in NASA ground facilities. Extensive flight instrumentation for inlet performance comparisons provided flight data that also lend insight into supersonic inlet operation during atmospheric turbulence. Pressure and flow direction measurements near the inlet gave results different from conventional accelerometer data normally used for flight determination of turbulence severity. A nonturbulent atmospheric temperature excursion during an XB-70 flight caused inlet duct pressure variations as extreme as those experienced during heavy turbulence on the YF-12 airplane.

Smith, R. H.; Bauer, C. A.

1974-01-01

151

Nuclear fuel assembly coolant control  

US Patent & Trademark Office Database

An apparatus for controlling the flow of coolant through a nuclear fuel assembly, in which a coolant flow restrictor 26 having longitudinal ducts 30 is provided with plug members 48, 49, 50 of different lengths. The plug members 48, 49, 50 are moved longitudinally by the effect of neutron induced growth on an actuating member 60. A connecting member 53 converts the growth of the actuating member 60 into a longitudinal movement of the plug members 48, 49, 50 so that they are progressively withdrawn from the flow restrictor 26 to increase the flow of coolant through the flow restrictor 26.

1991-11-19

152

Thermal-hydraulics of the PFB/LOFT lead rod loss-of-coolant experiments. [PWR  

SciTech Connect

Results of the four PBF/LOFT Lead Rod sequential blowdown tests conducted in the Power Burst Facility (PBF) are presented. The primary objective of the test series was to evaluate the extent of mechanical deformation that would be expected to occur to low pressure (0.1 MPa), light water reactor design fuel rods subjected to a series of nuclear blowdown tests, and to determine if subjecting deformed fuel rods to subsequent testing would result in rod failure. The extent of mechanical deformation (buckling, collapse, or waisting of the cladding) was evaluated by comparison of cladding temperature versus system pressure response with out-of-pile experimental data, and by posttest visual examinations and cladding diametral measurements. Tests LLR-3, LLR-5, LLR-4, and LLR-4A were performed at system conditions of 595/sup 0/K coolant inlet temperature, 15.5 MPa system pressure, and 41, 46, 57 and 56 kW/m test rod peak linear powers, respectively, at initiation of blowdown. Cladding temperatures during the tests ranged from 870 to 1260/sup 0/K.

Varacalle, D.J. Jr.; Garner, R.W.; MacDonald, P.E.; Cox, W.R.

1980-01-01

153

Proposed reactor coolant density monitor  

SciTech Connect

Until now there has been no feasible method of monitoring coolant density in the environment of an operating reactor core. By analysis of output from self-powered neutron detectors (SPNDs) in the core of the Loss of Fluid Test (LOFT) Reactor, the author has successfully estimated local coolant densities under post-scram conditions during a large break loss of coolant transient. The model used for estimation is not fully explained by published principles on the interaction of gamma rays with SPNDs. However, based on the success of the model, the author proposes employing self powered gamma detectors (SPGDs) to monitor reactor coolant density and discusses areas of experimental work to establish the best conditions for this application. 9 refs., 12 figs.

Mackley, A.D.

1986-01-01

154

Vertical Reactor Coolant Pump Instabilities.  

National Technical Information Service (NTIS)

This paper describes the investigation conducted at the Tennessee Valley Authority's Sequoyah Nuclear Power Plant to determine and correct increasing vibrations in the vertical reactor coolant pumps. Diagnostic procedures to determine the vibration causes...

1985-01-01

155

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

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

156

A smart design of coolant tank leak testing equipment in car manufacture using fault detection and isolation observer based method  

Microsoft Academic Search

In car manufacture industry (in Shanghai), we need to do leak test for coolant tank. Normally, many coolant tanks e.g. 5 have to be tested at the same time. The traditional test system has only one pressured liquid input with a single pressure sensor and a temperature sensor to monitor and control the coolant tank leak test system. Once a

C. J. Li; T. Z. Qi; Z. Q. Zhang

2008-01-01

157

Assessment of the Activation, Decay Heat, and Waste Disposal of a Dual Coolant Lithium Lead Test Blanket Module for ITER  

Microsoft Academic Search

The US is proposing a test blanket module (TBM) to be placed in half of the three dedicated test ports of ITER. The TBM is based on the dual coolant lithium lead (DCLL) blanket concept. Conventional ferritic steel (F82H) is used as the structure of the first wall (FW), the two breeder channels, the back plate, the inlet\\/out piping, and

M. Z. Youssef; M. E. Sawan

2005-01-01

158

Oregon inlet: Hydrodynamics, volumetric flux and implications for larval fish transport  

SciTech Connect

The temporal response of Oregon Inlet currents to atmospheric forcing and sea level fluctuations is analyzed using time and frequency domain analysis. Temporally persistent and spatially extensive ebb and flood events are identified using data sets from both within and outside of Oregon Inlet. Prism estimates are made to generate a time series of volumetric flux of water transported through the inlet. Water masses flooding into the Pamlico Sound via Oregon Inlet are identified in temperature (T) and salinity (S) space to determine their source of origin. Correlations are examined between the atmospheric wind field, the main axial slope of the inlet`s water level, inlet flow and T, S properties. Synoptic scale atmospheric wind events are found to dramatically and directly affect the transport of water towards (away from) the inlet on the ocean side, in concert with the contemporaneous transport away from (towards) the inlet on the estuary side, and a subsequent flooding into (out of) the estuary via Oregon Inlet. Thus, while astronomical tidal flooding and ebbing events are shown to be one-sided as coastal waters either set-up or set-down, synoptic scale wind events are shown to be manifested as a two-sided in-phase response set-up and set-down inside and outside the inlet, and thus are extremely effective in driving currents through the inlet. These subinertial frequency flood events are believed to be essential for both the recruitment and subsequent retention of estuarine dependent larval fish from the coastal ocean into Pamlico Sound. Year class strength of these finish may be determined annually by the relative strength and timing of these climatological wind events.

Nichols, C.R. [National Oceanic and Atmospheric Administration, Silver Springs, MD (United States); Pietrafesa, L.J. [North Carolina State Univ., Raleigh, NC (United States). Department of Marine, Earth and Atmospheric Sciences

1997-05-01

159

Planar Inlet Design and Analysis Process (PINDAP)  

NASA Technical Reports Server (NTRS)

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.

Slater, John W.; Gruber, Christopher R.

2005-01-01

160

Navigating the thoracic inlet in children.  

PubMed

Though various approaches to the thoracic inlet have been described in adults, currently no guidelines exist in children. Reports in the literature of resection of thoracic inlet tumours in children are only anecdotal. Literature was reviewed to assess the various described approaches with reference to suitability in children. Experience with a 3.5-year-old boy having a thoracic inlet ganglioneuroma, using the anterior cervico-thoracic trap door incision demonstrated excellent access and minimal morbidity. We recommend the trap door incision as the preferable route for exploring thoracic inlet tumours in children. PMID:17973113

Jones, Vinci S; Pitkin, John

2008-04-01

161

FLOW FIELDS IN SUPERSONIC INLETS  

NASA Technical Reports Server (NTRS)

This computer program is designed to calculate the flow fields in two-dimensional and three-dimensional axisymmetric supersonic inlets. The method of characteristics is used to compute arrays of points in the flow field. At each point the total pressure, local Mach number, local flow angle, and static pressure are calculated. This program can be used to design and analyze supersonic inlets by determining the surface compression rates and throat flow properties. The program employs the method of characteristics for a perfect gas. The basic equation used in the program is the compatibility equation which relates the change in stream angle to the change in entropy and the change in velocity. In order to facilitate the computation, the flow field behind the bow shock wave is broken into regions bounded by shock waves. In each region successive rays are computed from a surface to a shock wave until the shock wave intersects a surface or falls outside the cowl lip. As soon as the intersection occurs a new region is started and the previous region continued only in the area in which it is needed, thus eliminating unnecessary calculations. The maximum number of regions possible in the program is ten, which allows for the simultaneous calculations of up to nine shock waves. Input to this program consists of surface contours, free-stream Mach number, and various calculation control parameters. Output consists of printed and/or plotted results. For plotted results an SC-4020 or similar plotting device is required. This program is written in FORTRAN IV to be executed in the batch mode and has been implemented on a CDC 7600 with a central memory requirement of approximately 27k (octal) of 60 bit words.

Sorenson, R. L.

1994-01-01

162

Method for removing cesium from a nuclear reactor coolant  

DOEpatents

A method of and system for removing cesium from a liquid metal reactor coolant including a carbon packing trap in the primary coolant system for absorbing a major portion of the radioactive cesium from the coolant flowing therethrough at a reduced temperature. A regeneration subloop system having a secondary carbon packing trap is selectively connected to the primary system for isolating the main trap therefrom and connecting it to the regeneration system. Increasing the temperature of the sodium flowing through the primary trap diffuses a portion of the cesium inventory thereof further into the carbon matrix while simultaneously redispersing a portion into the regeneration system for absorption at a reduced temperature by the secondary trap.

Colburn, R.P.

1983-08-10

163

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

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

164

Morphologic Analysis of Sebastian Inlet, Florida: Enhancements to the Tidal Inlet Reservoir Model.  

National Technical Information Service (NTIS)

Geomorphic analysis was conducted for Sebastian Inlet, FL to re- formulate an analytic model of shoal evolution and sediment bypassing. The Tidal Inlet Reservoir Model (Kraus 2002) was enhanced to include sediment pathways that allow seasonal reversals in...

G. A. Zarillo N. C. Kraus R. K. Hoeke

2003-01-01

165

1996 Coolant Flow Management Workshop  

NASA Technical Reports Server (NTRS)

The following compilation of documents includes a list of the 66 attendees, a copy of the viewgraphs presented, and a summary of the discussions held after each session at the 1996 Coolant Flow Management Workshop held at the Ohio Aerospace Institute, adjacent to the NASA Lewis Research Center, Cleveland, Ohio on December 12-13, 1996. The workshop was organized by H. Joseph Gladden and Steven A. Hippensteele of NASA Lewis Research Center. Participants in this workshop included Coolant Flow Management team members from NASA Lewis, their support service contractors, the turbine engine companies, and the universities. The participants were involved with research projects, contracts and grants relating to: (1) details of turbine internal passages, (2) computational film cooling capabilities, and (3) the effects of heat transfer on both sides. The purpose of the workshop was to assemble the team members, along with others who work in gas turbine cooling research, to discuss needed research and recommend approaches that can be incorporated into the Center's Coolant Flow Management program. The workshop was divided into three sessions: (1) Internal Coolant Passage Presentations, (2) Film Cooling Presentations, and (3) Coolant Flow Integration and Optimization. Following each session there was a group discussion period.

Hippensteele, Steven A. (Editor)

1997-01-01

166

Overview of the Light Aircraft Aerosol Research Inlet (LAARI)  

NASA Astrophysics Data System (ADS)

Aircraft provide a mobile platform for measuring vertical profile aerosol properties. The efficacy of these measurements, however, is constrained by the aerosol inlet sampling efficiency. Larger particles are often lost to turbulent deposition and impaction inside the inlet and sampling lines, respectively. This precludes the measurement of coarse mode particles, important to visibility and radiative transfer studies. Turbulent deposition of large particles occurs when the sample air stream slows down within the inlet from the aircraft velocity to the recommended sampling velocities of the aerosol instruments (\\sim10 m s-1). Low-turbulence inlets that reduce turbulent deposition through the use of a porous diffuser cones are necessary for large aircraft with air speeds of 80 to 200 m s-1, but these are not feasible for light aircraft because of space and power requirements and may not even be necessary given the low air speeds of small aircraft. We have designed an aerosol inlet for a light aircraft platform with an average air speed of 60 m s-1 and a sample flow rate of 28.5 L min-1. The hemi-elliptical shaped, stainless steel inlet is 12.7 cm long. The front orifice has a 0.3175 cm diameter and the internal diameter expands to 0.9525 cm over a length of 9.2075 cm at an included angle of 4.3\\deg. The linear velocity of the sample stream as it exits the inlet is 6.7 m s-1. The calculated Reynolds number (Re) at the opening is 11,430 and decreases to 3,811 at the inlet terminus, with a pressure drop across the inlet opening of only 42 mb at an average flight temperature and pressure. Sampling line impaction is reduced by decreasing the number of bends upstream of the instruments. We have accomplished this by designing a parallel sampling manifold that splits the sample stream into four separate streams, three of which are split from the primary sample stream at an angle of 15\\deg. Theoretical investigations of sample flow and particle losses are underway with Computational Fluid Dynamics (CFD) software from FlowLab. Wind tunnel analyses using a Vibrating Orifice Aerosol Generator (VOAG) with optical particle counters upstream and downstream of the inlet and sampling lines will validate the theoretical calculations and provide empirical sampling efficiency values. This new inlet design will facilitate the more efficient collection of ambient particles, especially those in the coarse mode, from light aircraft. Because light aircraft are less expensive to operate than large aircraft and can make measurements in the lower atmosphere on a more routine basis, the Light Aircraft Aerosol Research Inlet (LAARI) will herald a new era of measurement capabilities in satellite validation work, column closure tests, and climate change studies.

Bueno, P. A.; Taubman, B. F.; Marufu, L. T.

2004-12-01

167

Neutronics Features of a Dual Coolant Lithium Lead Test Blanket Module for ITER  

Microsoft Academic Search

Neutronics analysis was performed for a dual coolant lithium lead blanket module to be tested in ITER. The total radial depth of the TBM is 41.3 cm followed by a 30 cm thick inlet\\/outlet piping zone. The calculated local tritium breeding ratio in the DCLL TBM is 0.741. The annual tritium production in the TBM is 2.4 g. The total

M. E. Sawan; M. Z. Youssef

2005-01-01

168

Entropy considerations applied to shock unsteadiness in hypersonic inlets  

NASA Astrophysics Data System (ADS)

The stability of curved or rectangular shocks in hypersonic inlets in response to flow perturbations can be determined analytically from the principle of minimum entropy. Unsteady shock wave motion can have a significant effect on the flow in a hypersonic inlet or combustor. According to the principle of minimum entropy, a stable thermodynamic state is one with the lowest entropy gain. A model based on piston theory and its limits has been developed for applying the principle of minimum entropy to quasi-steady flow. Relations are derived for analyzing the time-averaged entropy gain flux across a shock for quasi-steady perturbations in atmospheric conditions and angle as a perturbation in entropy gain flux from the steady state. Initial results from sweeping a wedge at Mach 10 through several degrees in AEDC's Tunnel 9 indicates the bow shock becomes unsteady near the predicted normal Mach number. Several curved shocks of varying curvature are compared to a straight shock with the same mean normal Mach number, pressure ratio, or temperature ratio. The present work provides analysis and guidelines for designing an inlet robust to off- design flight or perturbations in flow conditions an inlet is likely to face. It also suggests that inlets with curved shocks are less robust to off-design flight than those with straight shocks such as rectangular inlets. Relations for evaluating entropy perturbations for highly unsteady flow across a shock and limits on their use were also developed. The normal Mach number at which a shock could be stable to high frequency upstream perturbations increases as the speed of the shock motion increases and slightly decreases as the perturbation size increases. The present work advances the principle of minimum entropy theory by providing additional validity for using the theory for time-varying flows and applying it to shocks, specifically those in inlets. While this analytic tool is applied in the present work for evaluating the stability of shocks in hypersonic inlets, it can be used for an arbitrary application with a shock.

Bussey, Gillian Mary Harding

169

Low Speed Performance of a Supersonic Axisymmetric Mixed Compression Inlet with Auxiliary Inlets.  

National Technical Information Service (NTIS)

The aerodynamic performance of a representative supersonic cruise inlet was investigated using a fan simulator coupled to the inlet to provide characteristic noise signatures and to pump the inlet flow. Data were obtained at Mach numbers from 0 to 0.2 for...

J. F. Wasserbauer R. W. Cubbison C. J. Trefny

1983-01-01

170

Glacial Geology of Muir Inlet, Southeast Alaska.  

National Technical Information Service (NTIS)

Muir Inlet is in the northeast part of Glacier Bay National Monument in Southeastern Alaska, about 135 kilometers northeast of Juneau. Muir Inlet is part of a large dendritic glacial valley system that has three tidal glaciers. It is flanked on the east, ...

G. M. Haselton

1966-01-01

171

Inlet Distortion Generation for a Transonic Compressor.  

National Technical Information Service (NTIS)

A single-stage transonic research compressor and test rig are to be used to obtain data on the effect of inlet flow distortion on compressor (and therefore engine) stall. Auxiliary injection was examined as a technique for generating distortion in inlet s...

I. Papamarkos

2004-01-01

172

External-Compression Supersonic Inlet Design Code  

NASA Technical Reports Server (NTRS)

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.

Slater, John W.

2011-01-01

173

Inlet Stability Solutions for Tributary Inflow.  

National Technical Information Service (NTIS)

Formulas in use relating to the flow of water through tidal inlets do not take into account the joint effects of inertia and tributary inflow that play a significant role in determining the characteristics of many inlets. In a proposed analytical model th...

F. F. Escoffier T. L. Walton

1979-01-01

174

76 FR 20179 - Endangered and Threatened Species: Designation of Critical Habitat for Cook Inlet Beluga Whale  

Federal Register 2010, 2011, 2012, 2013

...these species are characterized as having very high fat content, returning to the upper Inlet early in the...heavy ice scour, extreme tidal fluctuations, high silt content, low temperatures, and high turbidity work to limit any intertidal...

2011-04-11

175

Long life coolant pump technology  

NASA Technical Reports Server (NTRS)

Design concepts were investigated to improve space system coolant pump technology to be suitable for mission durations of two years and greater. These design concepts included an improved bearing system for the pump rotating elements, consisting of pressurized conical bearings. This design was satisfactorily endurance tested as was a new prototype pump built using various other improved design concepts. Based upon an overall assessment of the results of the program it is concluded that reliable coolant pumps can be designed for three year space missions.

1976-01-01

176

Research on Supersonic Inlet Bleed  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

177

System and method for determining coolant level and flow velocity in a nuclear reactor  

DOEpatents

A boiling water reactor includes a reactor pressure vessel having a feedwater inlet for the introduction of recycled steam condensate and/or makeup coolant into the vessel, and a steam outlet for the discharge of produced steam for appropriate work. A fuel core is located within a lower area of the pressure vessel. The fuel core is surrounded by a core shroud spaced inward from the wall of the pressure vessel to provide an annular downcomer forming a coolant flow path between the vessel wall and the core shroud. A probe system that includes a combination of conductivity/resistivity probes and/or one or more time-domain reflectometer (TDR) probes is at least partially located within the downcomer. The probe system measures the coolant level and flow velocity within the downcomer.

Brisson, Bruce William; Morris, William Guy; Zheng, Danian; Monk, David James; Fang, Biao; Surman, Cheryl Margaret; Anderson, David Deloyd

2013-09-10

178

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

NASA Technical Reports Server (NTRS)

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.

Marchionna, N. R.

1973-01-01

179

Interactions between an organic coolant and drops of molten lithium  

SciTech Connect

Twenty scoping experiments were performed to investigate the behavior of nominally 0.5 g molten lithium drops when released into 0.7 L of the organic coolant Therminol 66 at local atmospheric pressure using a vortex insertion technique. Diagnostics consisted of video and photographic imaging and several chemical analyses. Six coolant/Li temperature pairs were used: 300/300; 300/530; 300/770; 464/530; 600/530 and 600/770, all nominal in K. Because the coolant: Li weight ratio was 10{sup 3}, only rapid ({approximately}0.5 s) quenching reactions could be studied when T{sub Li} > {Tc}; when T{sub Li} {le} {Tc}, however, both rapid and slower (min) interactions could be investigated. In none of the experiments was there any indication of (a) a vigorous, self-sustaining chemical reaction between the lithium and the organic coolant, or (b) the formation of water-insoluble debris, in particular carbon. This work confirms the benign behavior at similar temperatures reported earlier by others.

Nelson, L.S.; Krueger, J.D.; Corradini, M.L. [Univ. of Wisconsin, Madison, WI (United States)

1994-11-01

180

Steady-state temperature distribution within a Brayton rotating unit operating in a power conversion system using helium-xenon gas  

NASA Technical Reports Server (NTRS)

The Brayton rotating unit (BRU), consisting of a turbine, an alternator, and a compressor, was tested as part of a Brayton cycle power conversion system over a side range of steady state operating conditions. The working fluid in the system was a mixture of helium-xenon gases. Turbine inlet temperature was varied from 1200 to 1600 F, compressor inlet temperature from 60 to 120 F, compressor discharge pressure from 20 to 45 psia, rotative speed from 32 400 to 39 600 rpm, and alternator liquid-coolant flow rate from 0.01 to 0.27 pound per second. Test results indicated that the BRU internal temperatures were highly sensitive to alternator coolant flow below the design value of 0.12 pound per second but much less so at higher values. The armature winding temperature was not influenced significantly by turbine inlet temperature, but was sensitive, up to 20 F per kVA alternator output, to varying alternator output. When only the rotational speed was changed (+ or - 10% of rated value), the BRU internal temperatures varied directly with the speed.

Johnsen, R. L.; Namkoong, D.; Edkin, R. A.

1971-01-01

181

Coolant tube curvature effects on film cooling as detected by infrared imagery  

NASA Technical Reports Server (NTRS)

Reported herein are comparative thermal film cooling footprints observed by infrared imagery from straight, curved and looped coolant tube geometries. It was hypothesized that the difference in secondary flow and turbulence structure of flow through these three tubes should influence the mixing properties between the coolant and mainstream. The coolant was injected across an adiabatic plate through a hole angled at 30 deg to the surface in line with the free stream flow. The data cover a range of blowing rates from 0.37 to 1.25 (mass flow per unit area of coolant divided by free stream). Average temperature difference between coolant and tunnel air was 25 C. Data comparisons confirmed that coolant tube curvature significantly influences film cooling effectiveness.

Papell, S. S.; Graham, R. W.

1979-01-01

182

F.E.L. Coolant.  

National Technical Information Service (NTIS)

The compatibility of a number of organic and inorganic materials with Freon-113 in ETA-II is studied. The stability of Freon-113 in the simulated electrical environment is also discussed. It would be desirable to use Freon-113 as the dielectric coolant be...

D. Schumann J. Lepper

1987-01-01

183

Observations of wave effects on inlet circulation  

NASA Astrophysics Data System (ADS)

Observations of water levels, winds, waves, and currents in Katama Bay, Edgartown Channel, and Katama Inlet on Martha's Vineyard, Massachusetts are used to test the hypothesis that wave forcing is important to circulation in inlet channels of two-inlet systems and to water levels in the bay between the inlets. Katama Bay is connected to the Atlantic Ocean via Katama Inlet and to Vineyard Sound via Edgartown Channel. A numerical model based on the momentum and continuity equations that uses measured bathymetry and is driven with observed water levels in the ocean and sound, ocean waves, and local winds predicts the currents observed in Katama Inlet more accurately when wave forcing is included than when waves are ignored. During Hurricanes Irene and Sandy, when incident (12-m water depth) significant wave heights were greater than 5 m, breaking-wave cross-shore (along-inlet-channel) radiation stress gradients enhanced flows from the ocean into the bay during flood tides, and reduced (almost to zero during Irene) flows out of the bay during ebb tides. Model simulations without the effects of waves predict net discharge from the sound to the ocean both during Hurricane Irene and over a 1-month period with a range of conditions. In contrast, simulations that include wave forcing predict net discharge from the ocean to the sound, consistent with the observations.

Orescanin, Mara; Raubenheimer, Britt; Elgar, Steve

2014-07-01

184

Boundary-Layer-Ingesting Inlet Flow Control  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

185

Boundary-Layer-Ingesting Inlet Flow Control  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

186

The effect of water content on the dielectric strength of polyalphaolefin (PAO) coolants  

Microsoft Academic Search

Many variables can affect the dielectric strength of coolants and insulating fluids including particulates, water content, temperature, viscosity, and pressure. The present paper evaluates the effects of dissolved water content, adjusted in a controlled manner, on the dielectric strength and the variability of breakdown voltages in synthetic polyalphaolefin (PAO) MIL-PRF-87252 coolants obtained from three different suppliers. Additionally, the effect on

S. Gunderson; G. Fultz; C. E. Snyder; J. Wright; L. Gschwender; S. Heidger

2011-01-01

187

Inlet design technology development - Supersonic cruise research  

NASA Technical Reports Server (NTRS)

An inlet technology development program for future supersonic cruise aircraft is in progress. Areas being emphasized are inlet aerodynamic and control system design requirements for efficient and reliable operation. Off-design conditions, such as angle of incidence, starting, and noise abatement are major considerations. Flow analysis procedures are being developed to predict the internal inviscid and viscous flows in axisymmtric supersonic inlets for these operating conditions. Also under development are control systems that will have significant interfaces with the engine control system, the flight control system, and the airframe avionics system. The analytical methods are being supported and validated with representative experiments.

Syberg, J.; Paynter, G. C.; Carlin, C. M.

1981-01-01

188

PC Program for Coastal Inlet Stability Analysis Using Escoffier Method.  

National Technical Information Service (NTIS)

This Coastal Engineering Technical Note (CETN) provides information for determining coastal inlet stability using a personal computer program which is a tool in the Coastal Inlet Management Package of the Coastal Inlets Research Program. Background on the...

N. C. Kraus W. C. Seabergh

1997-01-01

189

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2010 CFR

...CONTROLS ENGINE-TESTING PROCEDURES Engine...Standards § 1065.745 Coolants. (a) You may...antifreeze mixtures or other coolants that will be used in...b) For laboratory testing of liquid-cooled...inhibitors. (c) For coolants allowed in...

2009-07-01

190

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2010 CFR

...CONTROLS ENGINE-TESTING PROCEDURES Engine...Standards § 1065.745 Coolants. (a) You may...antifreeze mixtures or other coolants that will be used in...b) For laboratory testing of liquid-cooled...inhibitors. (c) For coolants allowed in...

2010-07-01

191

Hydraulic transients for loss of coolant accidents  

SciTech Connect

This paper discusses calculations related to hydraulics in a loss of coolant reactor accident. Earlier calculations ignored the effect of emergency coolant injection. Present results show that if the ECS flow is considered, reactor coolant flow is maintained for much longer periods. A computer program used to carry out the calculations is included in this report. (JDH)

Hinton, J H

1986-12-19

192

Control rod drive mechanism stator loss of coolant test  

Microsoft Academic Search

This report documents the stator loss of coolant test conducted at HEDL on the lead unit Control Rod Drive Mechanism (CRDM) in February, 1977. The purpose of the test was to demonstrate scram capability of the CRDM with an uncooled stator and to obtain a time versus temperature curve of an uncooled stator under power. Brief descriptions of the test,

L. Besel; R. Ibatuan

1977-01-01

193

Computational analysis of ramjet engine inlet interaction  

NASA Technical Reports Server (NTRS)

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.

Duncan, Beverly; Thomas, Scott

1992-01-01

194

33 CFR 117.289 - Hillsboro Inlet.  

Code of Federal Regulations, 2013 CFR

...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.289 Hillsboro Inlet. The drawspans of the SR A-1-A Drawbridge, mile 0.3 at Hillsboro Beach,...

2013-07-01

195

Wave Breaking at New River Inlet  

NASA Astrophysics Data System (ADS)

Measurements of wave breaking from SWIFT drifters at New River Inlet, NC (USA) show strong dependences on water depth, tidal currents, and wind forcing. The breaking dissipation rates span four orders of magnitude from calm conditions inside the Inlet to strong breaking outside of the Inlet. Wave breaking is enhanced during ebb tides when opposing currents cause incoming waves to steepen and when water depths are smallest over the outer shoals. Wave breaking is reduced during flood tides when following currents lengthen waves and when water depths are largest over the outer shoals. Winds modulate breaking of high frequency waves across all tides. Funding provided by the Office of Naval Research.Dissipation Rates at New River Inlet

Zippel, S.; Thomson, J. M.

2012-12-01

196

Sample inlet tube for ion source  

DOEpatents

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.

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

2002-09-24

197

Uranium Isotope Systematic in Saanich Inlet  

NASA Astrophysics Data System (ADS)

As a redox-sensitive element Uranium has become the focus of stable isotope studies. Based on the nuclear field shift effect [1], U isotope fractionation was predicted as a function of U(IV)-U(VI) exchange reactions with the insoluble reduced U(IV) species being heavier than the soluble oxidized U(VI) species. Recently, variations in 238U/235U were reported in low temperature aqueous and sedimentary environments [2,3] indicating that U deposited in well-oxygenated environments is characterized by light isotopic composition, whereas suboxic and anoxic deposits tend towards a heavy isotopic signature. U isotope fractionation has been hence proposed as a promising new paleo-redox proxy. In order to test the efficacy of U isotope fractionation to record oxidation states in marine systems, we are investigating sediment samples deposited over a range of redox conditions in the seasonally anoxic Saanich Inlet, on the east coast of Vancouver Island. We have also made ?238U measurements for water samples from above and below the redoxcline. The measurements were carried out by MC-ICPMS using 233U/236U-double spike technique. The data are reported as ?238U relative to NBL 112a with a 238U/235U ratio of 137.88 (2sd). External precision is better than 0.10 permil (2sd). Eleven analyses of seawater performed over the course of this work yielded ?238U of -0.41±0.07 permil (2sd). No clear difference in ?238U values has been found, thus far, in water samples collected at 10m (O2~380?M) and 200m (O2~1?M) depths from a single location in the middle of the inlet. The mean of two measurements of the deepwater sample yielded -0.43±0.01 permil (2sd). Two measurements of the shallow water sample yielded a mean value of -0.38±0.03 permil (2sd). The ?238U values for HF-HNO3 digestions of the organic rich sediments, one taken in the middle of the basin (3.11% organic carbon) below seasonally anoxic bottom waters (-0.22±0.01 permil, n=2), and the other taken from the sill (1.29% organic carbon) below well-oxygenated bottom waters (-0.22 permil, n=1) are identical. The ?238U value matches previously reported values for suboxic sediments from the Peru margin [3], but is lighter than organic rich sediments from the Black Sea [3], where the bottom waters are strongly euxinic. The consistency in ?238U vaues between previously investigated suboxic sediment samples [3] and our two sediment samples indicates that the magnitude of the U isotopic fractionation is identical between seawater and sediments deposited under a range of bottom water oxygen conditions from oxygenated to anoxic. However, differences between the U isotope compositions in Saanich Inlet and those from the Black Sea remain to be explained, if U isotope fractionation is be used as a quantitative proxy for paleoredox in ancient oceans. [1] Schauble (2007) GCA 71, 2170- 2189. [2] Stirling et al. (2007) EPSL 264, 208-225. [3] Weyer et al. (2007) GCA 72, 345-399.

Amini, M.; Holmden, C.; Francois, R.

2008-12-01

198

Turbine Inlet Analysis of Injected Water Droplet Behavior  

NASA Astrophysics Data System (ADS)

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 droplets. This will then lead to more droplets exiting the inlet and at larger diameters.

Hargrave, Kevin

199

Circulation exchange patterns in Sinclair Inlet, Washington  

USGS Publications Warehouse

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.

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

2013-01-01

200

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

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

201

Boundary-Layer-Ingesting Inlet Flow Control  

NASA Technical Reports Server (NTRS)

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.

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

2008-01-01

202

Patch testing of coolant fractions.  

PubMed

Dermatitis among machine operators, and others who are consistently exposed to cutting and grinding liquids, has presented the industrial physician with the problems of how to protect the machinist from the cause of his dermatitis and how to detect irritants that may be responsible for the skin problem. In order to examine the various components of machine coolant that might be responsible for causing a dermatitis reaction, 13 suspensions were prepared. They consisted of various combinations of New Codol¿ (coolant base), biocides, masking agent, tramp oil, used coolant and metal fragments. Patch test techniques were used to examine these suspensions for their potential to cause a localized skin irritation on plant employees. Two hundred and six New Process Gear employees were tested over a ten-month period. The participants were management, general salaried employees and hourly labor employees. There was not a single positive reaction in any one of the 206 individuals who completed their skin testing. Of the 206 tested, 29 persons were tested and retested a total of 62 times over a period of one to 25 weeks after the initial testing. In neither the testing nor the retesting was a positive patch test reaction -- irritant or allergic -- obtained. PMID:126305

Menter, P; Harrison, W; Woodlin, W G

1975-09-01

203

Flow tests of a single fuel element coolant channel for a compact fast reactor for space power  

NASA Technical Reports Server (NTRS)

Water flow tests were conducted on a single-fuel-element cooling channel for a nuclear concept to be used for space power. The tests established a method for measuring coolant flow rate which is applicable to water flow testing of a complete mockup of the reference reactor. The inlet plenum-to-outlet plenum pressure drop, which approximates the overall core pressure drop, was measured and correlated with flow rate. This information can be used for reactor coolant flow and heat transfer calculations. An analytical study of the flow characteristics was also conducted.

Springborn, R. H.

1971-01-01

204

Fuel-Coolant Interactions: Visualization and Mixing Measurements  

SciTech Connect

Dynamic X-ray imaging of fuel-coolant interactions (FCI), including quantitative measurement of fuel-coolant volume fractions and length scales, has been accomplished with a novel imaging system at the Nuclear Safety Research Center at the University of Wisconsin, Madison. The imaging system consists of visible-light high-speed digital video, low-energy X-ray digital imaging, and high-energy X-ray digital imaging subsystems. The data provide information concerning the melt jet velocity, melt jet configuration, melt volume fractions, void fractions, and spatial and temporal quantification of premixing length scales for a model fuel-coolant system of molten lead poured into a water pool (fuel temperatures 500 to 1000 K; jet diameters 10 to 30 mm; coolant temperatures 20 to 90°C). Overall results indicate that the FCI has three general regions of behavior, with the high fuel-coolant temperature region similar to what might be expected under severe accident conditions. It was observed that the melt jet leading edge has the highest void fraction and readily fragments into discrete masses, which then subsequently subdivide into smaller masses of length scales <10 mm. The intact jet penetrates <3 to 5 jet length/jet diameter before this breakup occurs into discrete masses, which continue to subdivide. Hydrodynamic instabilities can be visually identified at the leading edge and along the jet column with an interfacial region that consists of melt, vapor, and water. This interface region was observed to grow in size as the water pool temperature was increased, indicating mixing enhancement by boiling processes.

Loewen, Eric Paul; Bonazza, R.; Corradini, M. L.

2002-08-01

205

Fuel-Coolant Interactions: Visualization and Mixing Measurements  

SciTech Connect

Dynamic X-ray imaging of fuel-coolant interactions (FCI), including quantitative measurement of fuel-coolant volume fractions and length scales, has been accomplished with a novel imaging system at the Nuclear Safety Research Center at the University of Wisconsin, Madison. The imaging system consists of visible-light high-speed digital video, low-energy X-ray digital imaging, and high-energy X-ray digital imaging subsystems. The data provide information concerning the melt jet velocity, melt jet configuration, melt volume fractions, void fractions, and spatial and temporal quantification of premixing length scales for a model fuel-coolant system of molten lead poured into a water pool (fuel temperatures 500 to 1000 K; jet diameters 10 to 30 mm; coolant temperatures 20 to 90 deg. C). Overall results indicate that the FCI has three general regions of behavior, with the high fuel-coolant temperature region similar to what might be expected under severe accident conditions. It was observed that the melt jet leading edge has the highest void fraction and readily fragments into discrete masses, which then subsequently subdivide into smaller masses of length scales <10 mm. The intact jet penetrates <3 to 5 jet length/jet diameter before this breakup occurs into discrete masses, which continue to subdivide. Hydrodynamic instabilities can be visually identified at the leading edge and along the jet column with an interfacial region that consists of melt, vapor, and water. This interface region was observed to grow in size as the water pool temperature was increased, indicating mixing enhancement by boiling processes.

Loewen, Eric P. [Idaho National Engineering and Environmental Laboratory (United States); Bonazza, Riccardo [University of Wisconsin, Madison (United States); Corradini, Michael L. [University of Wisconsin, Madison (United States); Johannesen, Robert E

2002-08-15

206

INLET CHANNEL, EGRESS OF BURIED CONDUIT SEGMENT TO PEN CHANNEL ...  

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

INLET CHANNEL, EGRESS OF BURIED CONDUIT SEGMENT TO PEN CHANNEL NEAR GATE TOWER, LOOKING WEST FORM LEFT BANK OF INLET CHANNEL. KACHESS RIVER CHANNEL (1910) TO REAR BEYOND INLET CHANNEL - Kachess Dam, Inlet Channel, Kachess River, 1.5 miles north of Interstate 90 , Easton, Kittitas County, WA

207

Analysis of Buzz in a Supersonic Inlet  

NASA Technical Reports Server (NTRS)

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.

Chima, Rodrick V.

2012-01-01

208

Thermography of the New River Inlet plume and nearshore currents  

NASA Astrophysics Data System (ADS)

As part of the DARLA and RIVET experiments, thermal imaging systems mounted on a tower and in an airplane captured water flow in the New River Inlet, NC, USA. Kilometer-scale, airborne thermal imagery of the inlet details the ebb flow of the estuarine plume water mixing with ocean water. Multiple fronts, corresponding to the preferred channels through the ebb tidal delta, are imaged in the aerial data. A series of internal fronts suggest discreet sources of the tidal plume that vary with time. Focused thermal measurements made from a tower on the south side of the inlet viewed an area within a radius of a few hundred meters. Sub-meter resolution video from the tower revealed fine-scale flow features and the interaction of tidal exchange and wave-forced surfzone currents. Using the tower and airborne thermal image data we plan to provide geophysical information to compare with numerical models and in situ measurements made by other investigators. From the overflights, we will map the spatial and temporal extent of the estuarine plume to correlate with tidal phase and local wind conditions. From the tower data, we will investigate the structure of the nearshore flow using a thermal particle image velocimetry (PIV) technique, which is based on tracking motion of the surface temperature patterns. Long term variability of the mean and turbulent two-dimensional PIV currents will be correlated to local wave, tidal, and wind forcing parameters.

Chickadel, C.; Jessup, A.

2012-12-01

209

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

NASA Technical Reports Server (NTRS)

A model supersonic inlet with auxiliary inlet doors and boundary layer bleeds was acoustically tested in simulated low speed flight up to Mach 0.2 in the NASA Lewis 9 x 15 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. Previously announced in STAR as N83-27794

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

1983-01-01

210

Numerical simulation of scramjet inlet flow fields  

NASA Technical Reports Server (NTRS)

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.

Kumar, Ajay

1986-01-01

211

Miniature piezo electric vacuum inlet valve  

DOEpatents

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.

Keville, Robert F. (Valley Springs, CA); Dietrich, Daniel D. (Livermore, CA)

1998-03-24

212

Miniature piezo electric vacuum inlet valve  

DOEpatents

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.

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

1998-03-24

213

Titanium Aluminide Scramjet Inlet Flap Subelement Benchmark Tested  

NASA Technical Reports Server (NTRS)

A subelement-level ultimate strength test was completed successfully at the NASA Glenn Research Center (http://www.nasa.gov/glenn/) on a large gamma titanium aluminide (TiAl) inlet flap demonstration piece. The test subjected the part to prototypical stress conditions by using unique fixtures that allowed both loading and support points to be located remote to the part itself (see the photograph). The resulting configuration produced shear, moment, and the consequent stress topology proportional to the design point. The test was conducted at room temperature, a harsh condition for the material because of reduced available ductility. Still, the peak experimental load-carrying capability exceeded original predictions.

Krause, David L.; Draper, Susan L.

2005-01-01

214

Muir Glacier and Muir Inlet 1980  

USGS Multimedia Gallery

This ship-deck-based August 1980 photograph of Muir Glacier and Muir Inlet, Glacier Bay National Park and Preserve, St. Elias Mountains, Alaska, shows the nearly 200-ft-high retreating tidewater end of Muir Glacier with part of its face capped by a few angular pinnacles of ice, called séracs....

215

Antivortex Inlet Ribs for Fluid-Seals  

NASA Technical Reports Server (NTRS)

Instability in rotating machinery reduced. Ring of ribs fastened to existing stator in turbopump pressure-seal inlet. Ribs suppress swirl in flow entering seal. Rib concept offers relatively inexpensive solution to some lateral-instability problems in many other systems with rotating pressure seals.

Chen, W. C.; Beatty, R. F.; Jackson, E. D.

1984-01-01

216

INLET BOUNDARY CONDITIONS FOR EMBEDDED LES  

Microsoft Academic Search

The paper evaluates a new method to prescribe syn- thesized turbulent inlet boundary conditions. The method can also be used when prescribing turbulent uctuations at an interface between (U)RANS and LES regions when the o w enters the LES region. When making LES, DES or hybrid LES-RANS a precursor channel DNS is often used. The disadvan- tage of this method

Lars Davidson

217

Beach and Inlet Task Force Report (Florida).  

National Technical Information Service (NTIS)

Beach erosion and inlet shoaling have been determined by both public and private authorities to be a serious problem for the economy and general welfare of the citizens and residents of Florida. To effectively cope with this problem, the state must develo...

1978-01-01

218

Coanda Inlet/Jet Flap Diffuser Ejector.  

National Technical Information Service (NTIS)

The combination of a Coanda inlet and jet flap diffusion, for the achievement of high performance, low volume, thrust augmentation, has been investigated in a two-dimesnional experiment. The use of jet flap diffusion provides a mechanism for the achieveme...

M. Alperin

1972-01-01

219

AEROSOL SAMPLING INLETS AND INHALABLE PARTICLES  

EPA Science Inventory

The problem of sampling aerosols from the ambient atmosphere has been considered from a theoretical point of view. Following a review of the various samplers and inlets used in ambient sampling, the factors contributing to high sampling efficiency for large particles are discusse...

220

Automotive Air Filter Inlet Velocity Distributions  

Microsoft Academic Search

Laser sheet flow visualizations and laser Doppler anemometer velocity measurements have been performed to define the flow fields upstream of a clean rectangular automotive engine air filter mounted in laboratory test housings and model vehicular housings. The experiments have shown that the flow fields in the various housings present the filter with very different inlet flow distributions. Significant variations in

F. W. Chambers; S. H. Yao; R. A. Newman; R. Duran

1996-01-01

221

Evaluation of thermal energy storage options for precooling gas turbine inlet air.  

National Technical Information Service (NTIS)

Several approaches have been used to reduce the temperature of gas turbine inlet air. One of the most successful uses off-peak electric power to drive vapor-compression-cycle ice makers. The ice is stored until the next time high ambient temperature is en...

Z. I. Antoniak D. R. Brown M. K. Drost

1992-01-01

222

Inlet Housing for a Partial-Admission Turbine  

NASA Technical Reports Server (NTRS)

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.

Moye, Ralph; Myers, William; Baker, Kevin

2004-01-01

223

A model for fuel-coolant interactions  

Microsoft Academic Search

A model for fuel-coolant interactions is proposed. The interaction is divided into five stages: an initial perturbation which triggers the interaction and causes a vapour bubble to form at the fuel-coolant interface; bubble expansion and collapse with jetting; penetration of the fuel by the liquid jet; heat transfer from the fuel to the jet; the formation of a new bubble.

D J Buchanan

1974-01-01

224

Experimental study on simulated molten jet-coolant interactions  

Microsoft Academic Search

Molten fuel-coolant interactions in a jet contact mode was studied with respect to the safety of liquid-metal-cooled fast breeder reactors (LMFBRs). From a series of molten Wood's metal (melting point 79 °C) jet-water interaction experiments, several distinct modes of interaction behaviors were observed for various combinations of initial temperature conditions of the two fluids. A semi-empirical model for a minimum

Sa. Kondo; K. Konishi; M. Isozaki; S. Imahori; A. Furutani; D. J. Brear

1995-01-01

225

Analysis of coolant entrance boundary shape of porous region to control cooling along exit boundary  

NASA Technical Reports Server (NTRS)

A cooled porous region has a plane surface exposed to a specified spatially varying heat flux. The coolant leaves the region through this surface, and it is desired to control the flow distribution to maintain a specified uniform surface temperature. This is accomplished by having the coolant entrance surface shaped to provide in the region the necessary variation of path length and, hence, flow resistance. The surface shape at the coolant entrance is found by solving a Cauchy boundary value problem. An exact solution is obtained that will deal with a wide variety of heating distributions for both two- and three-dimensional shapes.

Siegel, R.; Snyder, A.

1983-01-01

226

Effect of corrugated characteristics on the liquid nitrogen temperature field of HTS cable  

NASA Astrophysics Data System (ADS)

In the high temperature superconducting (HTS) cable system, liquid nitrogen is usually chosen to be the coolant because of its low saturation temperature and large latent heat of vaporization. Thus, it is very important for superconducting cables that the liquid nitrogen temperature field keeps stable. However, the cryostat is usually made of flexible corrugated pipes and multi-layer insulation materials. The characteristics (e.g. wave pitch and wave depth) of corrugated pipes may have an effect on the heat exchange between cable and liquid nitrogen, even the whole temperature field of liquid nitrogen. In this paper, a two-dimensional model for 30 m long HTS cable has been modified to analyze the effect of corrugated characteristics on the temperature field of liquid nitrogen. The liquid nitrogen temperature difference between the outlet and the inlet of passage gradually increases as the wave pitch of the corrugated tube decreases and the wave depth increases.

Li, Z. M.; Li, Y. X.; Zhao, Y. Q.; Gao, C.; Qiu, M.; Chen, G. F.; Gong, M. Q.; Wu, J. F.

2014-01-01

227

Flow Control in a Compact Inlet  

NASA Astrophysics Data System (ADS)

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 secondary flow structures. Unlike the baseline, these secondary flow structures produced downwash along the centerline. The formation of such structures was caused by the core flow stagnating on the lower surface near the aerodynamic interface plane. Using the two-dimensional steady jet resulted in an increase in the spanwise flow within the inlet and a reduction in the energy content of the 350 Hz shedding frequency. Unsteady forcing did not show much improvement over steady forcing for this configuration. A spanwise varying control jet and a hybrid Coanda jet / vortex generator jets were tested to reduce the three-dimensionality of the flow field. It was found that anytime the flow control method suppressed separation along the centerline, counter-rotating vortices existed in the lower corners of the aerodynamic interface plane.

Vaccaro, John C.

228

Numerical study of innovative scramjet inlets coupled to combustors using hydrocarbon-air mixture  

NASA Astrophysics Data System (ADS)

The research objective is to use high-fidelity multi-physics Computational Fluid Dynamics (CFD) analysis to characterize 3-D scramjet flowfields in two novel streamline traced circular configurations without axisymmetric profiles. This work builds on a body of research conducted over the past several years. In addition, this research provides the modeling and simulation support, prior to ground (wind tunnel) and flight experiment programs. Two innovative inlets, Jaws and Scoop, are analyzed and compared to a Baseline inlet, a current state of the art rectangular inlet used as a baseline for on/off-design conditions. The flight trajectory conditions selected were Mach 6 and a dynamic pressure of 1,500 psf (71.82 kPa), corresponding to a static pressure of 43.7 psf (2.09 kPa) and temperature of 400.8 R° (222.67 C°). All inlets are designed for equal flight conditions, equal contraction ratios and exit cross-sectional areas, thus facilitating their comparison and integration to a common combustor design. Analysis of these hypersonic inlets was performed to investigate distortion effects downstream in common generic combustors. These combustors include a single cavity acting as flame holder and strategically positioned fuel injection ports. This research not only seeks to identify the most successful integrated scramjet inlet/combustor design, but also investigates the flow physics and quantifies the integrated performance impact of the two novel scramjet inlet designs. It contributes to the hypersonic air-breathing community by providing analysis and predictions on directly-coupled combustor numerical experiments for developing pioneering inlets or nozzles for scramjets. Several validations and verifications of General Propulsion Analysis Chemical-kinetic and Two-phase (GPACT), the CFD tool, were conducted throughout the research. In addition, this study uses 13 gaseous species and 20 reactions for an Ethylene/air finite-rate chemical model. The key conclusions of this research are: (1) Flow distortion in the innovative inlets is similar to some of the distortion in the Baseline inlet, despite design differences. In both innovative inlets, the resulting flowfield distortions were due to shock boundary layer interactions similar to those found in the Baseline. The Baseline and Jaws performance attributes are stronger than Scoop, but Jaws accomplishes this while eradicating the cowl lip interaction, and lessening the total drag and spillage penalties. (2) The innovative inlets work best on-design, whereas for off-design, the traditional inlet yields a higher performance. Although the innovative inlets' designs mitigated some of the issues encountered in traditional configurations, they underperform at off-design conditions. The strategy used in Jaws was less prone to interaction with the near wall flow, and yields lesser pressure losses and higher efficiency at on-design conditions compared to the others. In general, the overall values for Scoop seem lowest of all due to lesser entrainment. Its drag coefficient and thrust to mass capture ratios are higher than the Baseline configuration. (3) Early pressure losses and flow distortions actually aid downstream combustion in all cases. Although interactions captured by the viscous simulations for the on-design conditions increase losses in the inlets, they enhance turbulence in the isolator, favoring the mixing of air and fuel, and improving the overall factor of the system. Jaws inlet demonstrates the most valuable design with higher performance, but its factor later in the combustor drops relative to its rectangular counterpart. (4) A parametric study of the location and direction of injection is conducted to select the configuration for fuel penetration, mixing factor (factor) and other combustion qualities. Although the trends observed with and without chemical reactions are the same, the former yields roughly 10% higher mixing factor. Unlike at frozen conditions, when chemical reactions are considered, a high compression area was observed upstream of the cavity, not presen

Malo-Molina, Faure Joel

229

The 727 airplane side inlet low-speed performance confirmation model test for refanned JT8D engines  

NASA Technical Reports Server (NTRS)

The results of a low-speed wind tunnel test of a 0.3 scale model 727 airplane side inlet for JT8D-100 engines are presented. The objectives of the test were to develop lines for a full-scale flightworthy inlet, to evaluate inlet total pressure recovery and steady-state total pressure distortion, and to obtain model-scale distortion data which can be used in the assessment of the compatibility of the inlet with the JT8D-100 series engines. A secondary objective was to obtain internal/external cowl static pressures for the determination of nacelle loads. Two basic inlet models were tested at static, forward speed, angle-of-attack (inflow angle), and cross-wind conditions. One model was with and one without an acoustic ring. Two modifications to the models were also tested, one with the ring closer to the inlet throat and one with a larger lip. Test measurements consisted of inlet surface static pressure, engine face total pressure, inlet airflow, tunnel total pressure, tunnel total temperature and tunnel velocity. Total pressure traverses were taken directly behind the ring and strut. No dynamic measurements were taken.

Schuehle, A. L.

1974-01-01

230

Survey of Inlet Noise Reduction Concepts for Gas Turbine Engines.  

National Technical Information Service (NTIS)

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 d...

D. Chestnutt D. L. Lansing

1976-01-01

231

Physical Model Studies of Ponce DeLeon Inlet, Florida.  

National Technical Information Service (NTIS)

Work completed by the U.S. Army Engineer Waterways Experiment Station's (WES) Coastal and Hydraulics Laboratory represents several elements of the larger study of Ponce Deleon Inlet, Florida, aimed at improving navigation conditions within the inlet and p...

C. Dorrell G. S. Harkins P. Puckette

1997-01-01

232

46 CFR 45.155 - Inlets and discharge piping: Valves.  

Code of Federal Regulations, 2013 CFR

... false Inlets and discharge piping: Valves. 45.155 Section 45.155 Shipping...155 Inlets and discharge piping: Valves. (a) Except as provided in paragraphs...haveâ (1) An automatic nonreturn valve with a positive means for closing;...

2013-10-01

233

Integrated Analysis of Scramjet Flowpath with Innovative Inlets.  

National Technical Information Service (NTIS)

Significant progress has been achieved during the first year of this Challenge effort, in developing and simulating configurations which highlight the main scramjet inlet flow path alternatives. In particular, three different types of inward-turning inlet...

D. Risha D. V. Gaitonde F. Malo-Molina H. B. Ebrahimi

2007-01-01

234

Loss-of-coolant accident experiment at the AVR gas-cooled reactor  

Microsoft Academic Search

A landmark safety test has been conducted at the AVR-reactor, a high-temperature gas-cooled reactor (HTGR) in the Federal Republic of Germany owned by the Arbeitsgemeinschaft Versuchsreaktor, AVR in Juelich. The 46-MW(t), 15-MW(e) AVR reactor was subjected to a simulated loss-of-coolant accident (LOCA), a very severe occurrence in which the coolant escapes from the reactor core and no emergency system provides

K. Krueger; J. Cleveland

1990-01-01

235

6. View southwest, culvert inlet with canal bank completely removed. ...  

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

6. View southwest, culvert inlet with canal bank completely removed. Left to right: back of headwall; tops of high inlet barrels; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall along former edge of canal bank; dewatered canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

236

A Numerical Study of Hypersonic Forebody/Inlet Integration Problem  

NASA Technical Reports Server (NTRS)

A numerical study of hypersonic forebody/inlet integration problem is presented in the form of the view-graphs. The following topics are covered: physical/chemical modeling; solution procedure; flow conditions; mass flow rate at inlet face; heating and skin friction loads; 3-D forebogy/inlet integration model; and sensitivity studies.

Kumar, Ajay

1991-01-01

237

A summary of V/STOL inlet analysis methods  

NASA Technical Reports Server (NTRS)

Recent extensions and applications of the methods are emphasized. They include the specification of the Kutta condition for a slotted inlet, the calculation of suction and tangential blowing for boundary layer control, and the analysis of auxiliary inlet geometries at angles of attack. A comparison is made with experiment for the slotted inlet. An optimum diffuser velocity distribution was developed.

Hwang, D. P.

1981-01-01

238

Wind Tunnel Tests of a Shrouded Aircraft Inlet  

Microsoft Academic Search

We describe tests of a shrouded aerosol inlet for a high-altitude jet aircraft. Both the lip of the inlet and the shroud are NACA (National Committee for Aeronautics, now known as NASA, or National Aeronautics and Space Administration) airfoils. Wind tunnel tests show a smooth growth of the boundary layer in the inlet, with an undisturbed core more than 1

D. M. Murphy; M. E. Schein

1998-01-01

239

OPEN SEGMENT OF INLET CHANNEL, KACHESS RESERVOIR TO REAR, FROM ...  

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

OPEN SEGMENT OF INLET CHANNEL, KACHESS RESERVOIR TO REAR, FROM BERM OVER START OF BURIED CONDUIT SEGMENT OF INLET CHANNEL (6/96), LOOKING NORTHEAST - Kachess Dam, Inlet Channel, Kachess River, 1.5 miles north of Interstate 90 , Easton, Kittitas County, WA

240

Convective heat transfer on an inlet guide vane.  

PubMed

The flow and temperature fields around an inlet guide vane are determined numerically by a CFD method. Outer surface temperatures, heat transfer coefficient distributions, and static pressure distributions are presented. Three different thermal boundary conditions on the vane are analysed. The computed results are compared with experimental data. The governing equations are solved by a finite-volume method with the low Reynolds number version of the k-omega turbulence model by Wilcox implemented. It is found that the calculated results agree best with measurements if a conjugate heat transfer approach is applied and thus this wall condition is recommended for future investigations of film cooling of guide vanes and turbine blades. PMID:11460632

Holmer, M L; Eriksson, L E; Sunden, B

2001-05-01

241

Low speed performance of a supersonic axisymmetric mixed compression inlet with auxiliary inlets. [Lewis 9x15-ft anechoic wind tunnel tests  

NASA Technical Reports Server (NTRS)

The aerodynamic performance of a representative supersonic cruise inlet was investigated using a fan simulator coupled to the inlet to provide characteristic noise signatures and to pump the inlet flow. Data were obtained at Mach numbers from 0 to 0.2 for the inlet equipped with an auxiliary inlet system that provided 20 to 40 percent of the fan flow. Results show that inlet performance improved when the inlet bleed systems were sealed; when the freestream Mach number was increased; and when the auxiliary inlets were opened. The inlet flow could not be choked by either centerbody translation or by increasing the fan speed when the 40 percent auxiliary inlet was incorporated.

Wasserbauer, J. F.; Cubbison, R. W.; Trefny, C. J.

1983-01-01

242

High tip speed fan inlet noise reduction using treated inlet splitters and accelerating inlets (quiet engine program fan C scale model)  

NASA Technical Reports Server (NTRS)

A series of inlet suppression tests were run on a supersonic tip speed fan which employed an acoustically treated cowl wall, treated splitters and elevated average throat Mach numbers in various combinations. Results show appreciable fan noise reductions at high fan speeds; 15-18 PNdB. On the basis of inlet total pressure recovery loss per PNdb of noise reduction, an inlet with no splitters produced the most efficient design. However, greater reduction in noise was achieved with one splitter in the inlet. It was also noted that moderate increases in inlet Mach number increased noise in the acoustically treated inlets and that Mach numbers in excess of 0.65 were required before net noise reduction was realized.

Kazin, S. B.

1973-01-01

243

Petroleum geology of Cook Inlet basin - an exploration model  

USGS Publications Warehouse

Oil exploration commenced onshore adjacent to lower Cook Inlet on the Iniskin Peninsula in 1900, shifted with considerable success to upper Cook Inlet from 1957 through 1965, then returned to lower Cook Inlet in 1977 with the COST well and Federal OCS sale. Lower Cook Inlet COST No. 1 well, drilled to a total depth of 3,775.6 m, penetrated basinwide unconformities at the tops of Upper Cretaceous, Lower Cretaceous, and Upper Jurassic strata at 797.1, 1,540.8, and 2,112.3 m, respectively. Sandstone of potential reservoir quality is present in the Cretaceous and lower Tertiary rocks. All siltstones and shales analyzed are low (0 to 0.5 wt. %) in oil-prone organic matter, and only coals are high in humic organic matter. At total depth, vitrinite readings reached a maximum ave age reflectance of 0.65. Several indications of hydrocarbons were present. Oil analyses suggest that oils from the major fields of the Cook Inlet region, most of which produce from the Tertiary Hemlock Conglomerate, have a common source. More detailed work on stable carbon isotope ratios and the distribution of gasoline-range and heavy (C12+) hydrocarbons confirms this genetic relation among the major fields. In addition, oils from Jurassic rocks under the Iniskin Peninsula and from the Hemlock Conglomerate at the southwestern tip of the Kenai lowland are members of the same or a very similar oil family. The Middle Jurassic strata of the Iniskin Peninsula are moderately rich in organic carbon (0.5 to 1.5 wt. %) and yield shows of oil and of gas in wells and in surface seeps. Extractable hydrocarbons from this strata are similar in chemi al and isotopic composition to the Cook Inlet oils. Organic matter in Cretaceous and Tertiary rocks is thermally immature in all wells analyzed. Oil reservoirs in the major producing fields are of Tertiary age and unconformably overlie Jurassic rocks; the pre-Tertiary unconformity may be significant in exploration for new oil reserves. The unconformable relation between reservoir rocks and likely Middle Jurassic source rocks also implies a delay in the generation and expulsion of oil from Jurassic until late Tertiary when localized basin subsidence and thick sedimentary fill brought older, deeper rocks to the temperature required for petroleum generation. Reservoir porosities, crude oil properties, the type of oil field traps, and the tectonic framework of the oil fields on the west flank of the basin provide evidence used to reconstruct an oil migration route. The route is inferred to commence deep in the truncated Middle Jur ssic rocks and pass through the porous West Foreland Formation in the McArthur River field area to a stratigraphic trap in the Oligocene Hemlock Conglomerate and the Oligocene part of the Tyonek Formation at the end of Miocene time. Pliocene deformation shut off this route and created localized structural traps, into which the oil moved by secondary migration to form the Middle Ground Shoal, McArthur River, and Trading Bay oil fields. Oil generation continued into the Pliocene, but this higher API gravity oil migrated along a different route to the Granite Point field.

Magoon, L. B.; Claypool, G. E.

1981-01-01

244

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

245

Operating Instructions, Spandau Electrical Submersible Coolant Pumps.  

National Technical Information Service (NTIS)

Instructions are presented for the installation, electrical connection, cleaning and maintenance, replacement of bearings, and disassembly and reassembly of electrical submersible coolant pumps manufactured by Maschinenfabrik Spandau KG. (ERA citation 04:...

1979-01-01

246

Loss of Coolant Accident Testing Round Robin.  

National Technical Information Service (NTIS)

A loss of coolant accident (LOCA) round robin test program was conducted to evaluate experimental variations and experimental practices associated with the post quench ductility and breakaway oxidation testing techniques. A common set of high level parame...

B. Dunn D. Lutz D. J. Park E. Perez-Fero H. K. Yueh M. LeSaux R. J. Comstock Y. Yan Y. P. Lin

2013-01-01

247

Recovery Studies for Plutonium Machining Oil Coolant.  

National Technical Information Service (NTIS)

Lathe coolant oil, contaminated with plutonium and having a carbon tetrachloride diluent, is generated in plutonium machining areas at Rocky Flats. A research program was initiated to determine the nature of plutonium in this mixture of oil and carbon tet...

J. D. Navratil C. E. Baldwin

1977-01-01

248

Cryogenic-Coolant He-4-Superconductor Interaction.  

National Technical Information Service (NTIS)

The thermodynamic and thermal interaction between a type 2 composite alloy and cryo-coolant He4 was studied with emphasis on post quench phenomena of formvar coated conductors. The latter were investigated using a heater simulation technique. Overall heat...

S. Caspi J. Y. Lee Y. I. Kim R. J. Allen T. H. K. Frederking

1978-01-01

249

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2013 CFR

... ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels, Analytical...coolants that will be used in your engine in use. (b) For laboratory testing of liquid-cooled engines, you may use water with or without rust...

2013-07-01

250

Reactor-Coolant-Pump-Seal Improvement.  

National Technical Information Service (NTIS)

An investigation of PWR reactor coolant pump seal performance at seven operating nuclear power plants equipped with Combustion Engineering designed Nuclear Steam Supply Systems was performed between May and November of 1981. Also, a video tape training fi...

W. W. Albert

1982-01-01

251

Reactor Coolant Pump Seals: Improving Their Performance.  

National Technical Information Service (NTIS)

Large CANDU plants are benefitting from transient-resistant four-year reliable reactor coolant pump seal lifetimes, a direct result of AECL's 20-year comprehensive seal improvement program involving R and D staff, manufacturers, and plant designers and op...

N. E. Pothier R. Metcalfe

1986-01-01

252

Advanced Technology Inlet Design, NRA 8-21 Cycle II: DRACO Flowpath Hypersonic Inlet Design  

NASA Technical Reports Server (NTRS)

The report outlines work performed in support of the flowpath development for the DRACO engine program. The design process initiated to develop a hypersonic axisymmetric inlet for a Mach 6 rocket-based combined cycle (RBCC) engine is discussed. Various design parametrics were investigated, including design shock-on-lip Mach number, cone angle, throat Mach number, throat angle. length of distributed compression, and subsonic diffuser contours. Conceptual mechanical designs consistent with installation into the D-21 vehicle were developed. Additionally, program planning for an intensive inlet development program to support a Critical Design Review in three years was performed. This development program included both analytical and experimental elements and support for a flight-capable inlet mechanical design.

Sanders, Bobby W.; Weir, Lois J.

1999-01-01

253

Coolant passage heat transfer with rotation  

NASA Technical Reports Server (NTRS)

The objective is to develop a heat transfer and pressure drop data base, computational fluid dynamic techniques, and correlations for multi-pass rotating coolant passages with and without flow turbulators. The experimental effort is focused on the simulation of configurations and conditions expected in the blades of advanced aircraft high pressure turbines. With the use of this data base, the effects of Coriolis and buoyancy forces on the coolant side flow can be included in the design of turbine blades.

Hajek, T. J.; Higgins, A. W.

1985-01-01

254

Coolant passage heat transfer with rotation  

NASA Technical Reports Server (NTRS)

The objective is to develop a heat transfer and pressure drop data base, computational fluid dynamic techniques and heat transfer correlations for rotating multipass coolant passages, with and without flow tabulators. The experimental effort is focused on the simulation of configurations and conditions expected in the blades of advanced aircraft high pressure turbines. With the use of this data base, the effects of Coriolis and buoyancy forces on the coolant side flow can be included in the design of turbine blades.

Hajek, T. J.; Wagner, J. H.; Johnson, B. V.

1987-01-01

255

Biodegradation of waste coolant fluid. Final report  

SciTech Connect

Operation of a pilot aerobic digester for 2 years demonstrated that waste coolant used in metal-cutting operations could be biologically degraded. Chemical oxygen demand levels discharging from the digester were reduced to less than 2% of the feedstock. Waste coolant from three separate sources was used. The study indicated that application of a commercial digester to Bendix waste disposal methods could save thousands of dollars now spent for hauling waste offsite.

Young, D.A

1985-01-01

256

A new approach for the design of hypersonic scramjet inlets  

NASA Astrophysics Data System (ADS)

A new methodology has been developed for the design of hypersonic scramjet inlets using gas dynamic relations. The approach aims to find the optimal inlet geometry which has maximum total pressure recovery at a prescribed design free stream Mach number. The design criteria for inlet is chosen as shock-on-lip condition which ensures maximum capture area and minimum intake length. Designed inlet geometries are simulated using computational fluid dynamics analysis. The effects of 1D, 2D inviscid and viscous effects on performance of scramjet inlet are reported here. A correction factor in inviscid design is reported for viscous effects to obtain shock-on-lip condition. A parametric study is carried out for the effect of Mach number at the beginning of isolator for the design of scramjet inlets. Present results show that 2D and viscous effects are significant on performance of scramjet inlet. Present simulation results are matching very well with the experimental results available from the literature.

Raj, N. Om Prakash; Venkatasubbaiah, K.

2012-08-01

257

Unstart Coupling Mechanism Analysis of Multiple-Modules Hypersonic Inlet  

PubMed Central

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.

Wang, Lei; Cao, Shibin

2013-01-01

258

Gas chromatography-full scan mass spectrometry determination of traces of chemical warfare agents and their impurities in air samples by inlet based thermal desorption of sorbent tubes.  

PubMed

A sensitive gas chromatography-mass spectrometry (GC-MS) based analytical method was developed for detection of the chemical warfare agents (CWA) and related compounds in air/vapor samples. The method uses a Tenax TA packed GC liner as an air/vapor sampling tube and Programmable Temperature-Vaporization (PTV) GC inlet as the thermal desorber. This approach eliminates secondary focusing step and allows transfer of desorbed analytes as sharp bands directly to the head of GC column. Use of a Peltier element for rapid cooling eliminates need for an external coolant. Minimal logistic and hardware needs make the method relatively inexpensive and especially suitable for a mobile laboratory. The limits of detection (LODs) of 0.8-2.9ng on tube for selected nerve and blister agents were achieved in the full scan MS mode. Simple derivatization method applied for detection of Lewisites 1 and 2 did not affect simultaneous analysis of other agents. The method was extensively evaluated with authentic CWA during the field trainings of the inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW). The environmental area and personal samples were collected for a semi-quantitative determination of averaged airborne CWA concentration levels. PMID:22251886

Terzic, Oliver; Swahn, Irvine; Cretu, Gheorghita; Palit, Meehir; Mallard, Gary

2012-02-17

259

Effect of afterburner lights and inlet unstarts on a mixed compression inlet turbofan engine operating at Mach 2.5  

NASA Technical Reports Server (NTRS)

Data are presented to show the response of an uncontrolled inlet to afterburner lightoff disturbances when a mixed-compression inlet is coupled to a turbofan engine. The results show a significant upstream shock excursion when the afterburner lights which is a result of the direct communication between the afterburner region and the inlet by means of the fan duct and fan stages. In addition results of a waveform analysis on the inlet pressure response to the afterburner light is presented. Inlet unstarts and their effect on operation of the propulsion system is also discussed.

Baumbick, R. J.; Batterton, P. G.; Daniele, C. J.

1975-01-01

260

Denitrification and Oxygen Cycling in Saanich Inlet  

NASA Astrophysics Data System (ADS)

Saanich Inlet, British Columbia is a seasonally anoxic fjord and therefore an ideal location to study seasonal changes in productivity and respiration. We have collected monthly profiles of dissolved oxygen and oxygen/nitrogen/argon ratios in this estuary since April 2008. These measurements allow us to explain deviations of gas concentrations from equilibrium with the atmosphere by separating the effects of physical processes, which affect all three gases, from biological processes, which only affect oxygen and nitrogen. The bottom water in this fjord becomes anoxic due to a sill that restricts water inflow and high rates of primary productivity at the surface that result in aerobic decomposition at depth. This profile is reset on an irregular basis by flushing events that allow oxygenated water from outside Saanich Inlet to enter the basin. An increase in oxygen concentrations below 90 m between sampling in April and May 2008 suggested that a renewal occurred between these cruises. Data from the VENUS project, which has deployed a CTD at 96 m in Saanich Inlet, confirms this hypothesis. Although aerobic respiration resulted in a continuous depletion in oxygen at intermediate depths during the summer, the dissolved nitrogen/argon profile over the full depth of the inlet remained remarkably constant from May through August. A persistent maximum in the nitrogen/argon ratio of 5% above the expected ratio at equilibrium was observed in the deepest 25 m at our station. The stability of the profile over the summer implies that a steady state was quickly established following the renewal. The excess nitrogen gas was produced by denitrifying and/or anammox bacteria that decompose organic matter in suboxic environments. Denitrification involves the use of nitrate to oxidize organic carbon and anammox utilizes nitrite to oxidize ammonium. Despite denitrifying bacteria preferentially reducing 14N-NO3- to produce isotopically light N2, the maximum ?15N- N2 of 1.2‰ coincided with the maximum nitrogen gas excess. This observation suggests that when denitrification occurred, all available nitrate was converted to N2 and that the nitrate consumed was substantially enriched in 15N relative to natural isotopic abundances. We will explore our data set using a mass balance approach.

Manning, C. C.; Hamme, R. C.; Bourbonnais, A.

2008-12-01

261

RECLAMATION OF POLYPHENYL NUCLEAR REACTOR COOLANT BY SOLVENT TREATMENT  

Microsoft Academic Search

Laboratory studies were conducted to develop methods to reclaim ; degraded terphenyl nuclear reactor coolant. A solvent treatment process to ; reclaim high boiler or spent coolant is described. A preliminary evaluation of ; the reclamination process is presented. Technical evaluation of products as well ; as a theoretical analysis of the effects of reclaimed coolant on coolant ; decomposition

D. A. Scola; J. S. Adams

1963-01-01

262

50 CFR 226.220 - Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas).  

Code of Federal Regulations, 2012 CFR

...Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas). 226.220...Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas). Critical...Inlet, Alaska, for the Cook Inlet beluga whale as described in paragraphs...

2012-10-01

263

50 CFR 226.220 - Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas).  

Code of Federal Regulations, 2011 CFR

...Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas). 226.220...Critical habitat for the Cook Inlet beluga whale (Delphinapterus leucas). Critical...Inlet, Alaska, for the Cook Inlet beluga whale as described in paragraphs...

2011-10-01

264

Testing and evaluation of small cavitating venturis with water at low inlet subcooling  

NASA Astrophysics Data System (ADS)

Cavitating venturi (CV) has been widely used as a flow control device in many different industries. In 1990, cavitating venturi was selected as the baseline flow control device in the Space Station Freedom's (SSF's) two-phase active thermal control system (ATCS). However, the design and the operation of the CVs used in SSF's ATCS is quite different in many ways from that typically used in the industry, such as low mass flow rate, small size, low pressure difference between inlet and outlet, and low inlet subcooling. During the prototypic ATCS' testing at NASA/Johnson Space Center, a phenomenon called overflow associated with throat superheat was observed. Although data was obtained and analyzed, no useful correlation for the superheat at rechoking was acquired. The objective of this study is to conduct a performance test on small CVs under low inlet subcooling. Water is used as the working fluid. Data acquisition and analysis are carried out under normal choked flow, over flow and recovery conditions. The effects of CV's size, fluid temperature, flow condition and inlet subcooling on CV performance are evaluated. Analysis of the test results showed that the superheat necessary for the onset of nucleation in pool boiling can be applied for the estimation of superheat required at rechoking for the CVs. With this postulated superheat and the predetermined CV loss coefficient, a equation as a function of inlet subcooling is recommended for predicting the pressure ratio at the recovery for the choked flow control in a mechanically pumped system.

Liou, S. G.; Chen, I. Y.; Sheu, J. S.

1998-01-01

265

Physics analysis of the LS-VHTR: Salt coolant and fuel block design  

SciTech Connect

The Liquid-Salt-Cooled Very High Temperature Reactor (LS-VHTR), also known as the Advanced High Temperature Reactor (AHTR), is a new, large [>2400 MW(t)], passively safe, high-temperature reactor concept. It uses a graphite-matrix coated-particle fuel and a graphite moderator similar to the fuel used in modular high-temperature gas-cooled reactors, but with a clean liquid-fluoride salt coolant. The neutronics properties of various salt coolant options are considered with respect to their coefficients of reactivity for various reactor configurations. In addition, several variations on the basic graphite block design of the AHTR are considered that would simplify refueling. The results show that the coolant coefficients of reactivity are negative or very small relative to other reactivity feedbacks, such as the fuel Doppler feedback. This allows several salt-coolants, even some with a positive coolant density coefficient, to be considered for use in the AHTR. In addition, parametric studies of assembly-type clustered rod configurations show that there is minimal impact on the reactivity coefficients and multiplication factors with appropriate cluster design choices. (authors)

Clarno, K. T.; Gehin, J. C. [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37931 (United States)

2006-07-01

266

NASCRIN - NUMERICAL ANALYSIS OF SCRAMJET INLET  

NASA Technical Reports Server (NTRS)

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.

Kumar, A.

1994-01-01

267

Investigation of REST-Class Hypersonic Inlet Designs  

NASA Technical Reports Server (NTRS)

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.

Gollan, Rowan; Ferlemann, Paul G.

2011-01-01

268

Stability of tidal inlets—Pass Cavallo, Texas  

NASA Astrophysics Data System (ADS)

Many tidal inlets are scoured in loose granular material, and the morphological changes in these inlets are discussed. The changes are the result of the predominantly fortnightly variations in the tide, the seasonal variations in storm activity and the occurrence of extreme meteorological events. The adjustment of an inlet to changes in the hydraulic environment and sudden changes in its morphology associated with extreme meteorological events is primarily via a change in the cross-sectional area. For a single-inlet bay system, the response of the inlet cross-sectional area can be determined using the stability analysis presented by Escoffier (1940). Rather than one inlet, many bays are connected to the ocean by several inlets. In this study, Escoffier's analysis is expanded to include the interaction of these inlets. In the analysis, the sediment carrying capacity of the inlet currents is characterized by the bottom shear stress. The stability analysis is applied to Pass Cavallo, Texas. Assuming the absence of future influences of tropical storms and hurricanes, the analysis shows that as a result of the opening of a companion inlet, Pass Cavallo ultimately will close.

van de Kreeke, J.

1985-07-01

269

Vortex tube can increase liquid hydrocarbon recovery at plant inlet  

SciTech Connect

Use of a vortex-tube device yields improved inlet gas-liquid separation, when compared with a Joule-Thomson system, but is less costly and complex than a true isentropic system, such as a turboexpander. Because the vortex-tube unit provides separation as well as pressure reduction, the capital cost of a Joule-Thomson system with valve and separator will be similar to that of the vortex-tube system. Future applications of vortex-tube units will be concentrated where performance improvements over Joule-Thomson units, at low capital cost, are required. The operating characteristics of a vortex tube permit gas, in part, to be reduced in temperature to less than that normally achievable through isenthalpic expansion. The following three examples show how vortex technology can be applied to achieve these aims.

Hajdik, B. [CBS Engineering Inc., Houston, TX (United States); Lorey, M. [Filtan Anlagenbau GmbH, Langenselbold (Germany); Steinle, J. [BEB Erdoel and Erdgas GmbH, Hannover (Germany); Thomas, K. [Falk and Thomas Engineering GmbH, Wettenberg (Germany)

1997-09-08

270

Localization and imaging of gangliosides in mouse brain tissue sections by laserspray ionization inlet[S  

PubMed Central

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.

Richards, Alicia L.; Lietz, Christopher B.; Wager-Miller, James; Mackie, Ken; Trimpin, Sarah

2012-01-01

271

Characteristic parameters of superconductor-coolant interaction including high Tc current density limits  

NASA Technical Reports Server (NTRS)

In the area of basic mechanisms of helium heat transfer and related influence on super-conducting magnet stability, thermal boundary conditions are important constraints. Characteristic lengths are considered along with other parameters of the superconducting composite-coolant system. Based on helium temperature range developments, limiting critical current densities are assessed at low fields for high transition temperature superconductors.

Frederking, T. H. K.

1989-01-01

272

Viscosity of alumina nanoparticles dispersed in car engine coolant  

SciTech Connect

The present paper, describes our experimental results on the viscosity of the nanofluid prepared by dispersing alumina nanoparticles (<50 nm) in commercial car coolant. The nanofluid prepared with calculated amount of oleic acid (surfactant) was tested to be stable for more than 80 days. The viscosity of the nanofluids is measured both as a function of alumina volume fraction and temperature between 10 and 50 C. While the pure base fluid display Newtonian behavior over the measured temperature, it transforms to a non-Newtonian fluid with addition of a small amount of alumina nanoparticles. Our results show that viscosity of the nanofluid increases with increasing nanoparticle concentration and decreases with increase in temperature. Most of the frequently used classical models severely under predict the measured viscosity. Volume fraction dependence of the nanofluid viscosity, however, is predicted fairly well on the basis of a recently reported theoretical model for nanofluids that takes into account the effect of Brownian motion of nanoparticles in the nanofluid. The temperature dependence of the viscosity of engine coolant based alumina nanofluids obeys the empirical correlation of the type: log ({mu}{sub nf}) = A exp(BT), proposed earlier by Namburu et al. (author)

Kole, Madhusree; Dey, T.K. [Thermophysical Measurements Laboratory, Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur 721 302 (India)

2010-09-15

273

Leading edge film cooling enhancement for an inlet guide vane with fan-shaped holes  

NASA Astrophysics Data System (ADS)

This paper describes the improvement of leading edge film cooling effectiveness for a turbine inlet guide vane by using fan-shaped film cooling holes. The modification details are presented in comparison with the base-line configuration of cylindrical holes. Numerical simulations were carried out for the base-line and modified configurations by using CFX, in which the ?-? turbulence model and scalable wall function were chosen. Contours of adiabatic film cooling effectiveness on the blade surfaces and span-wise distributions of film cooling effectiveness downstream the rows of cooling holes interested for the different cooling configurations were compared and discussed. It is showed that with the use of fan-shaped cooling holes around the leading edge, the adiabatic film cooling effectiveness can be enhanced considerably. In comparison with the cylindrical film cooling holes, up to 40% coolant mass flow can be saved by using fan-shaped cooling holes to obtain the comparable film cooling effectiveness for the studied inlet guide vane.

Liu, Jian-Jun; An, Bai-Tao; Liu, Jie; Zhan, W.

2010-12-01

274

Effects of coolant volatility on simulated HCDA bubble expansions. Technical report No. 10  

SciTech Connect

The effects of coolant volatility on the expansion dynamics and cover loading of hypothetical core disruptive accidents (HCDA) were studied by performing experiments with a transparent 1/30-scale model of a typical demonstration size loop-type liquid metal fast breeder reactor (LMFBR). Freon 113 and Freon 11 were used as coolant simulants of increasing volatility. High-pressure nitrogen gas (1450 psia) or flashing water (1160 psia) were used to simulate the qualitative features of sodium vapor or molten fuel expansions. To validate the use of constant mass and constant geometry experiments as a means of evaluating the effects of coolant volatility, a set of baseline experiments was performed in these configurations with the room temperature nitrogen bubble source. In all the experiments, the expanding HCDA bubbles, the motion of the coolant simulant, and the vessel loads were monitored by pressure transducers, a thermocouple in the bubble, and high-speed photography. Results of the constant mass experiments with the flashing water source show that higher volatility results in higher pressure driving the coolant slug and therefore higher impact loads. The Freon experiments had about 50% higher pressure in the upper core and bubble, a 30% larger slug impact impulse, and 25% greater expansion work done on the coolant slug. The higher pressure in the Freon experiments is believed due to vaporization of some of the Freon that mixes with the hot flashing water in the upper core very early in the expansion. Entrainment of coolant within the bubble and the bubble shape were comparable in the Freon and water experiments. Entrainment at slug impact varied between 20 and 40% of the bubble volume. The presence of internal vessel structures attenuated the slug impact impulse by about 50%, whether the coolant was Freon 113 or water. 79 figures, 23 tables.

Tobin, R.J.

1980-09-01

275

Handpiece coolant flow rates and dental cutting.  

PubMed

High-speed handpieces incorporate water coolant sprays to remove cutting debris and minimize thermal insult to the pulp. Little data exists on optimal coolant flow rates during clinical procedures. This study compared the effect of different coolant flow rates on diamond stone cutting efficiency. Cutting studies were performed on Macor machinable ceramic using a previously developed test regimen--a KaVo high-speed handpiece at a cutting force of 91.5 g (0.9 N). Cutting was performed with round end tapered medium grit diamond stones under cooling water flow rates of 15, 20, 25, 30 and 44 ml/min, with cutting rates determined as the time to transect the 13 mm square cross-section of the Macor bar. Each bur was used for five cuts, with six burs used for each flow rate, for a total of 150 measurements. The data were analyzed by one-way ANOVA with a post hoc Scheffé test. The cutting studies indicated that diamond stone cutting rates increased with higher coolant flow rates over the range of 15-44 ml/min. The data suggest that higher coolant flow rates promote cutting efficiency. PMID:11203868

von Fraunhofer, J A; Siegel, S C; Feldman, S

2000-01-01

276

Effect of Blowing on Boundary Layer of Scarf Inlet  

NASA Technical Reports Server (NTRS)

When aircraft operate in stationary or low speed conditions, airflow into the engine accelerates around the inlet lip and pockets of turbulence that cause noise and vibration can be ingested. This problem has been encountered with engines equipped with the scarf inlet, both in full scale and in model tests, where the noise produced during the static test makes it difficult to assess the noise reduction performance of the scarf inlet. NASA Langley researchers have implemented boundary layer control in an attempt to reduce the influence of the flow nonuniformity in a 12-in. diameter model of a high bypass fan engine mounted in an anechoic chamber. Static pressures and boundary layer profiles were measured in the inlet and far field acoustic measurements were made to assess the effectiveness of the blowing treatment. The blowing system was found to lack the authority to overcome the inlet distortions. Methods to improve the implementation of boundary layer control to reduce inlet distortion are discussed.

Gerhold, Carl H.; Clark, Lorenzo R.

2004-01-01

277

Boundary-layer-ingesting inlet flow control system  

NASA Technical Reports Server (NTRS)

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.

Owens, Lewis R. (Inventor); Allan, Brian G. (Inventor)

2010-01-01

278

CFD numerical simulation of Archimedes spiral inlet hydrocyclone  

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

279

Superfluid plug as a control device for helium coolant  

NASA Technical Reports Server (NTRS)

New results are obtained on the characteristics of a superfluid plug as a nonmechanical control device for supplying cold helium vapor on demand from a superfluid-helium container. The data reported are for an Al2O3 ceramic plug having a nominal 5-micron pore size. A theoretical background and steady-state data are presented on mass flow rates and pressures as a function of liquid temperature. It is demonstrated that the superfluid plug can be employed as a flow control device in a control system designed to provide coolant on demand.

Karr, G. R.; Urban, E. W.

1980-01-01

280

Study of the convective heat transfer in rotating coolant channel  

NASA Astrophysics Data System (ADS)

An experimental and theoretical study of convective heat transfer in a coolant channel consisting of a rectangular-sectioned duct rotating around an orthogonal axis is presented, with application to cooled turbine rotor blades. Transient and steady-state techniques are used to measure the convective heat transfer coefficients. It is found that Coriolis acceleration has a beneficial influence on mean heat transfer. The results are analyzed using a three-dimensional Navier-Stokes model, and are explained by the influence of the Coriolis force which induces a secondary flow and distorts the velocity and temperature profiles.

Guidez, J.

1988-06-01

281

Survey of inlet noise reduction concepts for gas turbine engines  

NASA Technical Reports Server (NTRS)

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.

Lansing, D. L.; Chestnutt, D.

1976-01-01

282

Tidal inlet variability in Mississippi River delta plain  

SciTech Connect

Stratigraphic sequences of deltaic and shallow marine origin commonly contain sand bodies transgressively overlying lower delta-plain and delta-front deposits. Although generally ascribed to barriers formed during the destructive phase of the delta cycle, most of this sand is probably of tidal-inlet origin because of the high preservation potential for sediment deposited below the base of the retreating shoreface in deep migratory tidal channels and their associated tidal deltas. To facilitate the identification of such units, this paper reviews the temporal evolution of the inlet sand bodies found along the rapidly transgressive shoreline of the abandoned Holocene Mississippi River deltas. This study also reveals that tide dominance of a coastline is not simply a function of tide range and wave height; it depends largely on the tidal prism, an inlet parameter which, in Louisiana, changes rapidly over time. Three distinct stages can be identified in the evolutionary sequence for Louisiana tidal inlets: (1) wave-dominated inlets with flood-tidal deltas, (2) tide-dominated inlets with large ebb deltas, and (3) wide, transitional inlets with sand bodies confined to the throat section. As the inlets migrate during the transgression, they will leave behind on the continental shelf, tidal sand bodies with a landward succession of facies changing from those characteristic of wave dominance, into tide dominance, and back again to transitional or wave-dominated inlets.

Levin, D.; Nummedal, D.; Penland, S.

1983-09-01

283

CFD Models of a Serpentine Inlet, Fan, and Nozzle  

NASA Technical Reports Server (NTRS)

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

Chima, R. V.; Arend, D. J.; Castner, R. S.; Slater, J. W.; Truax, P. P.

2010-01-01

284

Lead Coolant Test Facility Development Workshop  

SciTech Connect

A workshop was held at the Idaho National Laboratory on May 25, 2005, to discuss the development of a next generation lead or lead-alloy coolant test facility. Attendees included representatives from the Generation IV lead-cooled fast reactor (LFR) program, Advanced Fuel Cycle Initiative, and several universities. Several participants gave presentations on coolant technology, existing experimental facilities for lead and lead-alloy research, the current LFR design concept, and a design by Argonne National Laboratory for an integral heavy liquid metal test facility. Discussions were focused on the critical research and development requirements for deployment of an LFR demonstration test reactor, the experimental scope of the proposed coolant test facility, a review of the Argonne National Laboratory test facility design, and a brief assessment of the necessary path forward and schedule for the initial stages of this development project. This report provides a summary of the presentations and roundtable discussions.

Paul A. Demkowicz

2005-06-01

285

Limits to fuel/coolant mixing  

SciTech Connect

The vapor explosion process involves the mixing of fuel with coolant prior to the explosion. A number of analysts have identified limits to the amount of fuel/coolant mixing that could occur within the reactor vessel following a core melt accident. Past models are reviewed and a sim plified approach is suggested to estimate the upper limit on the amount of fuel/coolant mixing pos sible. The approach uses concepts first advanced by Fauske in a different way. The results indicat that water depth is an important parameter as well as the mixing length scale D /SUB mix/ , and for large values of D /SUB mix/ the fuel mass mixed is limited to <7% of the core mass.

Corradini, M.L.; Moses, G.A.

1985-05-01

286

Geologic framework of lower Cook Inlet, Alaska  

USGS Publications Warehouse

Three seismic reflectors are present throughout the lower Cook Inlet basin and can be correlated with onshore geologic features. The reflections come from unconformities at the base of the Tertiary sequence, at the base of Upper Cretaceous rocks, and near the base of Upper Jurassic strata. A contour map of the deepest horizon shows that Mesozoic rocks are formed into a northeast-trending syncline. Along the southeast flank of the basin, the northwest-dipping Mesozoic rocks are truncated at the base of Tertiary rocks. The Augustine-Seldovia arch trends across the basin axis between Augustine Island and Seldovia. Tertiary rocks thin onto the arch from the north and south. Numerous anticlines, smaller in structural relief and breadth than the Augustine-Seldovia arch, trend northeast parallel with the basin, and intersect the arch at oblique angles. The stratigraphic record shows four cycles of sedimentation and tectonism that are bounded by three regional unconformities in lower Cook Inlet and by four thrust faults and the modern Benioff zone in flysch rocks of the Kenai Peninsula and the Gulf of Alaska. The four cycles of sedimentation are, from oldest to youngest, the early Mesozoic, late Mesozoic, early Cenozoic, and late Cenozoic. Data on organic geochemistry of the rocks from one well suggest that Middle Jurassic strata may be a source of hydrocarbons. Seismic data show that structural traps are formed by northeast-trending anticlines and by structures formed at the intersections of these anticlines with the transbasin arch. Stratigraphic traps may be formed beneath the unconformity at the base of Tertiary strata and beneath unconformities within Mesozoic strata.

Fisher, M. A.; Magoon, L. B.

1978-01-01

287

Emergency cooling analysis for the loss of coolant malfunction  

NASA Technical Reports Server (NTRS)

This report examines the dynamic response of a conceptual space power fast-spectrum lithium cooled reactor to the loss of coolant malfunction and several emergency cooling concepts. The results show that, following the loss of primary coolant, the peak temperatures of the center most 73 fuel elements can range from 2556 K to the region of the fuel melting point of 3122 K within 3600 seconds after the start of the accident. Two types of emergency aftercooling concepts were examined: (1) full core open loop cooling and (2) partial core closed loop cooling. The full core open loop concept is a one pass method of supplying lithium to the 247 fuel pins. This method can maintain fuel temperature below the 1611 K transient damage limit but requires a sizable 22,680-kilogram auxiliary lithium supply. The second concept utilizes a redundant internal closed loop to supply lithium to only the central area of each hexagonal fuel array. By using this method and supplying lithium to only the triflute region, fuel temperatures can be held well below the transient damage limit.

Peoples, J. A.

1972-01-01

288

On-Line Coolant Chemistry Analysis  

SciTech Connect

Impurities in the gas coolant of the space nuclear power plant (SNPP) can provide valuable indications of problems in the reactor and an overall view of system health. By monitoring the types and amounts of these impurities, much can be implied regarding the status of the reactor plant. However, a preliminary understanding of the expected impurities is important before evaluating prospective detection and monitoring systems. Currently, a spectroscopy system is judged to hold the greatest promise for monitoring the impurities of interest in the coolant because it minimizes the number of entry and exit points to the plant and provides the ability to detect impurities down to the 1 ppm level.

LM Bachman

2006-07-19

289

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

NASA Technical Reports Server (NTRS)

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.

Dustin, M. O. (inventor)

1975-01-01

290

Inlet-Compressor Analysis using Coupled CFD Codes  

NASA Technical Reports Server (NTRS)

Propulsion performance and operability are key factors in the development of a successful aircraft. For high-speed supersonic aircraft, mixed-compression inlets offer high performance but are susceptible to an instability referred to as unstart. An unstart occurs when a disturbance originating in the atmosphere or the engine causes the shock system to be expelled from the inlet. This event can have adverse effects on control of the aircraft, which is unacceptable for a passenger plane such as the high speed civil transport (HSCT). The ability to predict the transient response of such inlets to flow perturbations is, therefore, important to the proper design of the inlet and the control measures used to prevent unstart. Computational fluid dynamics (CFD) is having an increasing role in the analysis of individual propulsion components. Isolated inlet studies are relatively easy to perform, but a major uncertainty is the boundary condition used at the inlet exit to represent the engine - the so-called compressor face boundary condition. A one-dimensional (1-D) Euler inlet simulation showed that the predicted inlet unstart tolerance to free-stream pressure perturbations can vary by as much as a factor of about six, depending on the boundary condition used. Obviously a thorough understanding of dynamic interactions between inlets and compressors/fans is required to provide the proper boundary condition. To aid in this understanding and to help evaluate possible boundary conditions, an inlet-engine experiment was conducted at the University of Cincinnati. The interaction of acoustic pulses, generated in the inlet, with the engine were investigated. Because of the availability of experimental data for validation, it was decided to simulate the experiment using CFD. The philosophy here is that the inlet-engine system is best simulated by coupling (existing) specialized CFD component-codes. The objectives of this work were to aid in a better understanding of inlet-compressor interaction physics and the formulation of a more realistic compressor-face boundary condition for time-accurate CFD simulations of inlets. Previous simulations have used 1-D Euler engine simulations in conjunction with 1-D Euler and axisymmetric Euler inlet simulations. This effort is a first step toward CFD simulation of an entire engine by coupling multidimensional component codes.

Cole, Gary; Suresh, Ambady; Townsend, Scott

1999-01-01

291

Critical Propulsion Components. Volume 4; Inlet and Fan/Inlet Accoustics Team  

NASA Technical Reports Server (NTRS)

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.

2005-01-01

292

Element immersed in coolant of nuclear reactor  

Microsoft Academic Search

This paper describes the method of processing a coolant-displacement rod of a nuclear reactor, preparatory to the installation of the rod in the nuclear reactor, to preclude the formation undesirably of an unsupported permanent axial gap in the cladding of the rod over the anticipated time of use of the rod in the nuclear reactor by reason of neutron bombardment

1990-01-01

293

Welds chilled by liquid coolant manifold  

NASA Technical Reports Server (NTRS)

Liquid coolant chill tool provides uniform cooling to materials adjacent to weld areas on long or contoured butt welds. This tool incorporates a manifold that clamps to the weld joint by vacuum and circulates liquid in direct contact with adjacent material.

Odor, M. E.; Whiffen, E. E.

1966-01-01

294

Application of Coolant-Chip-Ejector Drilling.  

National Technical Information Service (NTIS)

A program was conducted to evaluate the Sandvik coolant-chip-ejector drilling system for manufacturing purposes at Rock Island Arsenal. The Sandvik 'Ejector Drill', which has an insert-type head with unique cutting geometries, produces small chips which a...

R. A. Kirschbaum

1977-01-01

295

Coolant quality for magnetic resonance imaging systems  

Microsoft Academic Search

As radiologists demand increased power, speed and duty cycle from their magnetic resonance imaging (MRI) systems, thermal management of the gradient sub-system becomes more challenging. A heat exchanger in the MRI system cools heat-generating components by pumping water through hollow copper tubing, which also carries high electrical currents. Water is used as a coolant because of its high specific heat

Julie Wong; Garron K Morris

2008-01-01

296

Simulated Loss of Coolant Accident test  

Microsoft Academic Search

In the event of a major pipe break in the heavy water coolant loop of one of the SRP reactors, the Emergency Cooling System (ECS) would be activated to inject light water into the reactor. For the hypothetical worst case assumed for safety analysis considerations, one of the three ECS addition valves would fail to open and one of the

Steimke

1984-01-01

297

Primary coolant pumps for pressurized water reactors  

Microsoft Academic Search

From international nuclear industries fair; Basel, Switzerland (16 Oct ; 1972). The circulating pumps developed and constructed by Maschinenfabrik ; ANDRITZ AG for nuclear power stations with light and heavy water reactors are ; described, with a detailed account of the main coolant pumps for pressurized ; water reactors. A short description is presented of the development, ; construction, trial

Moritz

1972-01-01

298

Two Stage Supersonic Inlet (TSSI):10-inch Model Calculations.  

National Technical Information Service (NTIS)

The bifurcated inlet examined in this study (which is one of several being considered in the High Speed Research (HSR) Program) was chosen based upon paper trade studies of axisymmetric, single sided, and bifurcated inlets. For a given compression ratio a...

D. Chapman C. F. Smith G. E. Smith

2005-01-01

299

Advanced Scour Monitoring at Indian River Inlet, Delaware  

Microsoft Academic Search

The scour holes threatening the bridge over Indian River Inlet, Delaware are unique in their size and location, and thus demand an innovative approach to their observation. Typical bridge scour occurs at the base of support structures. However, scour at Indian River Inlet has developed two large holes over 25m deep that flank the bridge. The deepest part of one

J. T. Hayden; J. A. Puleo; J. H. Macmahan

2008-01-01

300

Numerical analysis of water-jet inlet flow  

Microsoft Academic Search

Water-jet propulsion system is widely used to high speed marine vessels by virtue of high propulsive efficiency, good maneuverability, and less vibration. The flow through the waterjet inlet will be analysed in more detail. In order to validate the computational method the CFD results are compared with experimental data for a model scale water-jet inlet duct. During the validation process,

Shuxiang Guo; Yao Chen

2009-01-01

301

Validation of WIND for a Series of Inlet Flows  

NASA Technical Reports Server (NTRS)

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.

Slater, John W.; Abbott, John M.; Cavicchi, Richard H.

2002-01-01

302

Prediction of sound radiation from different practical jet engine inlets  

Microsoft Academic Search

Computer codes, capable of producing accurate results for nondimensional wave numbers (based on duct radius) of up to 20, were developed and used to generate results for various other inlet configurations. Both reflection coefficients and radiation patterns were calculated by the integral solution procedure for the following five inlet configurations: the NASA Langley Bellmouth, the NASA Lewis JT-15D-1 ground test

B. T. Zinn; W. L. Meyer

1981-01-01

303

Long-Term Coastal Inlet Channel Area Stability.  

National Technical Information Service (NTIS)

The equilibrium-area concept for tidal inlets has been a useful approach to understand the adjustment of an entrance channel's minimum cross-sectional area to the basic hydraulic and sedimentation characteristics of the inlet and bay it serves. This paper...

W. C. Seabergh

2003-01-01

304

Survey of inlet noise reduction concepts for gas turbine engines  

NASA Technical Reports Server (NTRS)

This paper presents an overview of advanced concepts for the suppression of noise in the inlets of gas turbine engines. Noise suppression concepts are described, the directions of current research are reviewed, and problem areas requiring further work are indicated. The discussion focuses on acoustic liners, high Mach number inlets, active acoustic absorption, water vapor injection, and blade row reflection.

Lansing, D. L.; Chestnutt, D.

1976-01-01

305

The performance of a centrifugal compressor with high inlet prewhirl  

Microsoft Academic Search

The performance requirements of centrifugal compressors usually include a broad operating range between surge and choke. This becomes increasingly difficult to achieve as increased pressure ratio is demanded. In order to suppress the tendency to surge and extend the operating range at low flow rates, inlet swirl is often considered through the application of inlet guide vanes. To generate high

A. Whitfield; A. H. Abdullah

1998-01-01

306

An evaluation of thermal energy storage options for precooling gas turbine inlet air  

NASA Astrophysics Data System (ADS)

Several approaches have been used to reduce the temperature of gas turbine inlet air. One of the most successful uses off-peak electric power to drive vapor-compression-cycle ice makers. The ice is stored until the next time high ambient temperature is encountered, when the ice is used in a heat exchanger to cool the gas turbine inlet air. An alternative concept would use seasonal thermal energy storage to store winter chill for inlet air cooling. The objective of this study was to compare the performance and economics of seasonal thermal energy storage in aquifers with diurnal ice thermal energy storage for gas turbine inlet air cooling. The investigation consisted of developing computer codes to model the performance of a gas turbine, energy storage system, heat exchangers, and ancillary equipment. The performance models were combined with cost models to calculate unit capital costs and levelized energy costs for each concept. The levelized energy cost was calculated for three technologies in two locations (Minneapolis, Minnesota and Birmingham, Alabama). Precooling gas turbine inlet air with cold water supplied by an aquifer thermal energy storage system provided lower cost electricity than simply increasing the size of the turbine for meteorological and geological conditions existing in the Minneapolis vicinity. A 15 to 20 percent cost reduction resulted for both 0.05 and 0.2 annual operating factors. In contrast, ice storage precooling was found to be between 5 and 20 percent more expensive than larger gas turbines for the Minneapolis location. In Birmingham, aquifer thermal energy storage precooling was preferred at the higher capacity factor and ice storage precooling was the best option at the lower capacity factor. In both cases, the levelized cost was reduced by approximately 5 percent when compared to larger gas turbines.

Antoniak, Z. I.; Brown, D. R.; Drost, M. K.

1992-12-01

307

Parametric Analysis of a Hypersonic Inlet using Computational Fluid Dynamics  

NASA Astrophysics Data System (ADS)

For CFD validation, hypersonic flow fields are simulated and compared with experimental data specifically designed to recreate conditions found by hypersonic vehicles. Simulated flow fields on a cone-ogive with flare at Mach 7.2 are compared with experimental data from NASA Ames Research Center 3.5" hypersonic wind tunnel. A parametric study of turbulence models is presented and concludes that the k-kl-omega transition and SST transition turbulence model have the best correlation. Downstream of the flare's shockwave, good correlation is found for all boundary layer profiles, with some slight discrepancies of the static temperature near the surface. Simulated flow fields on a blunt cone with flare above Mach 10 are compared with experimental data from CUBRC LENS hypervelocity shock tunnel. Lack of vibrational non-equilibrium calculations causes discrepancies in heat flux near the leading edge. Temperature profiles, where non-equilibrium effects are dominant, are compared with the dissociation of molecules to show the effects of dissociation on static temperature. Following the validation studies is a parametric analysis of a hypersonic inlet from Mach 6 to 20. Compressor performance is investigated for numerous cowl leading edge locations up to speeds of Mach 10. The variable cowl study showed positive trends in compressor performance parameters for a range of Mach numbers that arise from maximizing the intake of compressed flow. An interesting phenomenon due to the change in shock wave formation for different Mach numbers developed inside the cowl that had a negative influence on the total pressure recovery. Investigation of the hypersonic inlet at different altitudes is performed to study the effects of Reynolds number, and consequently, turbulent viscous effects on compressor performance. Turbulent boundary layer separation was noted as the cause for a change in compressor performance parameters due to a change in Reynolds number. This effect would not be noticeable if laminar flow was assumed. Mach numbers up to 20 are investigated to study the effects of vibrational and chemical non-equilibrium on compressor performance. A direct impact on the trends on the kinetic energy efficiency and compressor efficiency was found due to dissociation.

Oliden, Daniel

308

Effects of Inlet Turbulence and Rotor/Stator Interactions on the Aerodynamics and Heat Transfer of a Large-Scale Rotating Turbine Model. Part 4. Aerodynamic Data Tabulation.  

National Technical Information Service (NTIS)

A combined experimental and analytical program was conducted to examine the effects of inlet turbulence and airfoil heat transfer. The experimental portion of the study was conducted in a large-scale (approx. 5X engine), ambient temperature, rotating turb...

R. P. Dring H. D. Joslyn M. F. Blair

1987-01-01

309

Inlet flow field investigation. Part 1: Transonic flow field survey  

NASA Technical Reports Server (NTRS)

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.

Yetter, J. A.; Salemann, V.; Sussman, M. B.

1984-01-01

310

Catalytically-Promoted Analyte Derivatization Inside a Gas Chromatographic Inlet  

PubMed Central

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.

Fowler, William K.; Gamble, Kelly J.; Wright, Amber R.

2010-01-01

311

Computational Analysis of a Low-Boom Supersonic Inlet  

NASA Technical Reports Server (NTRS)

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.

Chima, Rodrick V.

2011-01-01

312

The effect of fuel thermal conductivity on the behavior of LWR cores during loss-of-coolant accidents  

NASA Astrophysics Data System (ADS)

The effect of variation in thermal conductivity of light water reactor fuel elements on core response during loss-of-coolant accident scenarios is examined. Initially, a simplified numerical analysis is utilized to determine the time scales associated with dissipation of stored energy from the fuel into the coolant once the fission reaction is stopped. The analysis is then followed by full reactor system thermal-hydraulics analysis of a typical boiling and pressurized water reactor subjected to a large break loss-of-coolant accident scenario using the TRACE code. Accordingly, sensitivity analyses to examine the effect of an increase in fuel thermal conductivity, up to 500%, on fuel temperature evolution during these transients are performed. Given the major differences in thermal-hydraulics design aspects of boiling and pressurized water reactors, different fuel and temperature responses during the simulated loss-of-coolant transients are observed.

Terrani, Kurt A.; Wang, Dean; Ott, Larry J.; Montgomery, Robert O.

2014-05-01

313

Coupled reactor physics and coolant dynamics of heavy liquid metal coolant systems.  

National Technical Information Service (NTIS)

Cooling of advanced nuclear designs with heavy liquid metals such as lead or lead-bismuth eutectic offers the potential for plant simplifications and higher operating efficiencies compared to previously considered liquid metal coolants such as sodium or N...

J. E. Cahalan F. E. Dunn T. A. Taiwo

1999-01-01

314

Investigation of a mixed compression axisymmetric inlet at Mach number 5.3  

NASA Technical Reports Server (NTRS)

The hypersonic diffuser portion of an uncooled high performance mixed compression, axisymmetric inlet suitable for subsonic burning engines was designed and tested. Performance of a model with a 25.4-cm capture diameter was measured in a wind tunnel and the results were compared with theoretical predictions calculated by a comprehensive computer program. All tests were conducted at a Mach number of 5.3 at a total temperature of 667 K and a total pressure of 11.57 atm. The angle of attack ranged from 0 to + or - 3 deg. Performance at angle of attack remained high. Reasonably high performance in the throat (maximum throat pitot-pressure recovery of 77 percent and an average value of 58 percent) was obtained at 0 deg angle of attack with relatively large amounts of boundary-layer bleed (11 to 22 percent of the capture mass flow). The computer program used in the design of this inlet is considered marginally adequate for predicting hypersonic inlet flow fields. Although the program as it now exists is very useful, an improved computer program that more accurately predicts the boundary layer and the shock-wave-boundary-layer interaction and accounts for boundary-layer bleed should be developed for reliability predicting hypersonic inlet flow fields.

Latham, E. A.; Sorenson, N. E.; Smeltzer, D. B.

1972-01-01

315

Design criteria for Waste Coolant Processing Facility and preliminary proposal 722 for Waste Coolant Processing Facility  

SciTech Connect

This document contains the design criteria to be used by the architect-engineer (A-E) in the performance of Titles 1 and 2 design for the construction of a facility to treat the biodegradable, water soluble, waste machine coolant generated at the Y-12 plant. The purpose of this facility is to reduce the organic loading of coolants prior to final treatment at the proposed West Tank Farm Treatment Facility.

Not Available

1991-09-27

316

Automotive Air Filter Inlet Velocity Distributions*  

NASA Astrophysics Data System (ADS)

Laser sheet flow visualizations and laser Doppler anemometer velocity measurements have been performed to define the flow fields upstream of a clean rectangular automotive engine air filter mounted in laboratory test housings and model vehicular housings. The experiments have shown that the flow fields in the various housings present the filter with very different inlet flow distributions. Significant variations in velocity magnitude occur across the plane of the flow entering the filter. One standard laboratory test housing is designed to accommodate a range of different size filters conveniently. This design results in flow field variations that may bias performance measurements. Housings used in vehicles often are designed with primary consideration given to underhood packaging. The measurements show that a typical model vehicle housing produces regions of separated and recirculating flow that extend to as much as forty percent of the projected area of the filter. Estimates of clean filter efficiency performed using the measured velocity distributions suggest that the non-uniform velocity distributions produce small but significant differences in the initial filter efficiency.

Chambers, F. W.; Yao, S. H.; Newman, R. A.; Duran, R.

1996-11-01

317

Silicon Microleaks for Inlets of Mass Spectrometers  

NASA Technical Reports Server (NTRS)

Microleaks for inlets of mass spectrometers used to analyze atmospheric gases can be fabricated in silicon wafers by means of photolithography, etching, and other techniques that are commonly used in the manufacture of integrated circuits and microelectromechanical systems. The microleaks serve to limit the flows of the gases into the mass-spectrometer vacuums to specified very small flow rates consistent with the capacities of the spectrometer vacuum pumps. There is a need to be able to precisely tailor the dimensions of each microleak so as to tailor its conductance to a precise low value. (As used here, "conductance" signifies the ratio between the rate of flow in the leak and the pressure drop from the upstream to the downstream end of the leak.) To date, microleaks have been made, variously, of crimped metal tubes, pulled glass tubes, or frits. Crimped-metal and pulled-glass-tube microleaks cannot readily be fabricated repeatably to precise dimensions and are susceptible to clogging with droplets or particles. Frits tend to be differentially chemically reactive with various gas constituents and, hence, to distort the gas mixtures to be analyzed. The present approach involving microfabrication in silicon largely overcomes the disadvantages of the prior approaches.

Harpold, Dan; Hasso, Niemann; Jamieson, Brian G.; Lynch, Bernard A.

2009-01-01

318

Is Cervical Inlet Patch Important Clinical Problem?  

PubMed Central

AIM: In this study we aim to determine the frequency of Inlet Patch (IP) and its association to clinical symptoms and draw attention to be aware of this heterotopic gastric mucosa. METHODS: This study was a prospective case series that IP was detected in the upper gastrointestinal endoscopy. Patients with laringopharyngeal reflux symptoms underwent endoscopy between March 2009 and July 2012 in two different institutions. All the biopsies were obtained from if there is the IP lesion and antral or/and gastric mucosa. The data was prospectively evaluated. The prevalence was compared with those of patients that did not determine IP in the study period. RESULTS: 3907 upper gastrointestinal system endoscopy was performed while 123 patients consist of 51 male and 72 female was determined as IP. The prevalence of IP in patiens who underwent upper gastrointestinal endoscopy was 3.14% in our study. The majority of symptoms of those who had IP were laringopharyngeal reflux symptoms. Heterotopic gastric mucosa was fixed in 114 cases while 28 chronic inflammation, 9 esophagitis, 5 intestinal metaplasia, 4 glicogenic acanthosis were obtained as additional findings in pathological examinations. CONCLUSION: Heterotopic gastric mucosa in the proximal esophagus is a frequent finding if the endoscopist is aware of this entity. The importance of IP is the increasing number of cases of neoplastic transformation. Symptomatic patients should be treated and should be considered of the complications of heterotopic gastric mucosa.

SAHIN, Gurol; ADAS, Gokhan; KOC, Bora; AKCAKAYA, Adem; DOGAN, Yasar; Goksel, Suha; Yalcin, Ozben

2014-01-01

319

Review of cladding-coolant interactions during LWR accident transients  

SciTech Connect

Some of the coolant-cladding interactions that can take place during the design basis loss-of-coolant accident and the Three Mile Island loss-of-coolant accident are analyzed. The physical manifestations of the interactions are quite similar, but the time sequences involved can cause very different end results. These results are described and a listing is given of the main research programs that are involved in coolant-cladding interaction research.

Hobson, D.O.

1980-01-01

320

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2010 CFR

... 1 2009-01-01 2009-01-01 false Coolant tank tests. 23.1063 Section 23.1063 ...AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except...

2009-01-01

321

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2010 CFR

... 1 2010-01-01 2010-01-01 false Coolant tank tests. 23.1063 Section 23.1063 ...AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except...

2010-01-01

322

Heat Storage Capacity of Gelled Coolants in ice Vests  

Microsoft Academic Search

A number of ice vest manufacturers offer cooling garments containing gelled coolant rather than pure water. No data has been provided on the heat storage capacity of gelled coolants, however, or on product-specific guidelines for the use of these ice vests. An experiment was designed to compare the heat storage capacity of three commercial ice vests containing gelled coolant materials

SHELDON R. COLEMAN

1989-01-01

323

Lead Coolant Test Facility—Design concept and requirements  

Microsoft Academic Search

The Idaho National Laboratory prepared a preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a Lead Coolant Test Facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead–bismuth eutectic. Based on review

Soli Khericha; Eric Loewen

2011-01-01

324

EFFECTS OF COOLANT SUPPLY METHODS AND CUTTING CONDITIONS ON TOOL LIFE IN END MILLING TITANIUM ALLOY  

Microsoft Academic Search

Titanium machining poses a great challenge to cutting tools due to its severe negative influence on tool life primarily due to high temperature generated and strong adhesion in the cutting area. Thus, various coolant supply methods are widely used to improve the machining process. On account of this, tool life and cutting force are investigated based on dry cutting, flood

J. Sun; Y. S. Wong; M. Rahman; Z. G. Wang; K. S. Neo; C. H. Tan; H. Onozuka

2006-01-01

325

Effect of Microstructure on Failure Behavior of Light Water Reactor Coolant Piping under Severe Accident Conditions  

Microsoft Academic Search

In a severe accident of light water reactors, the reactor coolant system (RCS) piping might be subjected to thermal loads caused by the decay heat of the deposited fission products and the heat transfer from the hot gases, with an internal pressure in some accident sequences. Tests on the RCS piping failure were performed along with high temperature tensile and

Yuhei HARADA; Yu MARUYAMA; Akio MAEDA; Hiroaki SHIBAZAKI; Tamotsu KUDO; Akihide HIDAKA; Kazuichiro HASHIMOTO; Jun SUGIMOTO

1999-01-01

326

Development of Acoustic Leak Detection and Localization Methods for Inlet Piping of Fugen Nuclear Power Plant  

Microsoft Academic Search

The development work carried out on Fugen NPP is focused on detection of a small leakage on the reactor's inlet feeder pipes at an early stage by an acoustic leak detection method with usage of high-temperature resistant microphones. Specifically, the leak rate of 0.046 m\\/h has been chosen as a target detection capability for this system. A cross-correlation technique has

Sergey SHIMANSKIY; Takashi IIJIMA; Yosuke NAOI

2004-01-01

327

Summary of recent investigations of inlet flow distortion effect on engine stability  

NASA Technical Reports Server (NTRS)

A review is presented of recent experimental results, analytical procedures and test techniques employed to evaluate the effects of inlet flow distortion on the stability characteristics of representative afterburning turbofan and turbojet compression systems. Circumferential distortions of pressure and temperature, separately and in combination are considered. Resulting engine sensitivity measurements are compared with predictions based on simplified parallel compressor models and with several distortion descriptor parameters.

Graber, E. J., Jr.; Braithwaite, W. M.

1974-01-01

328

The performance of a centrifugal compressor with high inlet prewhirl  

SciTech Connect

The performance requirements of centrifugal compressors usually include a broad operating range between surge and choke. This becomes increasingly difficult to achieve as increased pressure ratio is demanded. In order to suppress the tendency to surge and extend the operating range at low flow rates, inlet swirl is often considered through the application of inlet guide vanes. To generate high inlet swirl angles efficiently, an inlet volute has been applied as the swirl generator, and a variable geometry design developed in order to provide zero swirl. The variable geometry approach can be applied to increase the swirl progressively or to switch rapidly from zero swirl to maximum swirl. The variable geometry volute and the swirl conditions generated are described. The performance of a small centrifugal compressor is presented for a wide range of inlet swirl angles. In addition to the basic performance characteristics of the compressor, the onsets of flow reversals at impeller inlet are presented, together with the development of pressure pulsations, in the inlet and discharge ducts, through to full surge. The flow rate at which surge occurred was shown, by the shift of the peak pressure condition and by the measurement of the pressure pulsations, to be reduced by over 40%.

Whitfield, A. [Univ. of Bath (United Kingdom). Dept. of Mechanical Engineering; Abdullah, A.H. [Univ. Technology Malaysia, Johore Baharu (Malaysia). Dept. of Mechanical Engineering

1998-07-01

329

New Configurations of Micro Plate-Fin Heat Sink to Reduce Coolant Pumping Power  

NASA Astrophysics Data System (ADS)

The thermal resistance of heat exchangers has a strong influence on the electric power produced by a thermoelectric generator (TEG). In this work, a real TEG device is applied to three configurations of micro plate-fin heat sink. The distance between certain microchannels is varied to find the optimum heat sink configuration. The particular focus of this study is to reduce the coolant mass flow rate by considering the thermal resistances of the heat sinks and, thereby, to reduce the coolant pumping power in the system. The three-dimensional governing equations for the fluid flow and the heat transfer are solved using the finite-volume method for a wide range of pressure drop laminar flows along the heat sink. The temperature and the mass flow rate distribution in the heat sink are discussed. The results, which are in good agreement with previous computational studies, show that using suggested heat sink configurations reduces the coolant pumping power in the system.

Rezania, A.; Rosendahl, L. A.

2012-06-01

330

Aerodynamic design of a supersonic three-dimensional inlet  

NASA Astrophysics Data System (ADS)

The results of designing and numerical gas-dynamic modeling a supersonic three-dimensional inlet of a new type are considered. A ramp of external compression of this inlet is the V-shaped body forming an initial plane oblique shock wave and a subsequent isentropic compression wave. The inlet incorporates an entrance section of internal compression, where also a plane oblique shock wave and a subsequent isentropic compression wave are formed by a cowl. The designed three-dimensional inlet has small inclination angles of compression surfaces, which ensures its low wave drag. According to the estimates of inlet efficiency in terms of the compression ratio and the total pressure recovery factor, it is close to the optimal two-dimensional shocked inlet of external compression considered by Oswatisch as well as Petrov and Ukhov. The flow in the inlet was computed with the use of the Euler and Navier — Stokes codes provided by the commercial package “FLUENT”. The flow in the inlet throat in the design regime computed under the inviscid flow approximation is uniform. The most substantial effect of the flow viscosity in this regime manifests itself in the interaction of the shock wave from the cowl with the boundary layer on the V-shaped compression body in the inlet internal duct. According to computed data, the boundary layer separation does not occur in this case; however, due to viscosity effects, reflected shock waves are formed here which results in significant deviations of flow structure as compared to the computed inviscid flow.

Goonko, Yu. P.; Alexandrov, E. A.

2010-03-01

331

Blade row dynamic digital compressor program. Volume 1: J85 clean inlet flow and parallel compressor models  

NASA Technical Reports Server (NTRS)

The results are presented of a one-dimensional dynamic digital blade row compressor model study of a J85-13 engine operating with uniform and with circumferentially distorted inlet flow. Details of the geometry and the derived blade row characteristics used to simulate the clean inlet performance are given. A stability criterion based upon the self developing unsteady internal flows near surge provided an accurate determination of the clean inlet surge line. The basic model was modified to include an arbitrary extent multi-sector parallel compressor configuration for investigating 180 deg 1/rev total pressure, total temperature, and combined total pressure and total temperature distortions. The combined distortions included opposed, coincident, and 90 deg overlapped patterns. The predicted losses in surge pressure ratio matched the measured data trends at all speeds and gave accurate predictions at high corrected speeds where the slope of the speed lines approached the vertical.

Tesch, W. A.; Steenken, W. G.

1976-01-01

332

Cooling Air Inlet and Exit Geometries on Aircraft Engine Installations  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

333

Estimation of additive forces and moments for supersonic inlets  

NASA Technical Reports Server (NTRS)

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.

Perkins, Stanley C., Jr.; Dillenius, Marnix F. E.

1991-01-01

334

Methods and apparatus for reducign inlet sleeve vibration  

SciTech Connect

This patent describes a steam turbine. It comprises: an outer cylinder and an inlet sleeve for receiving and transmitting steam; a restraining structure affixed to the outer cylinder having a radial dimension and an inner and an outer circumferential dimension; and one or more spline means for cooperating with the restraining structure affixed to the inlet sleeve and adapted to be disposed within the restraining structure within a tolerance, whereby the inlet sleeve is substantially restrained from radial oscillation in all directions by a relatively small tolerance between the inner circumferential dimension of the restraining structure and the spline and unrestrained from axial movement and thermal expansion.

Huang, K.P.

1992-10-06

335

Analysis of an advanced ducted propeller subsonic inlet  

NASA Technical Reports Server (NTRS)

It is shown that a time marching Navier-Stokes code called PARC can be utilized to provide a reasonable prediction of the flow field within an inlet for an advanced ducted propeller. The code validation was implemented for a nonseparated flow condition associated with the inlet functioning at angles-of-attack of zero and 25 deg. Comparison of the computational results with the test data shows that the PARC code with the propeller face fixed flow properties boundary conditions (BC) provided a better prediction of the inlet surface static pressures than the prediction when the mass flow BC was employed.

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

1992-01-01

336

Performance and boundary-layer evaluation of a sonic inlet  

NASA Technical Reports Server (NTRS)

Tests were conducted to determine the boundary layer characteristics and aerodynamic performance of a radial vane sonic inlet with a length/diameter ratio of 1 for several vane configurations. The sonic inlet was designed with a slight wavy wall type of diffuser geometry, which permits operation at high inlet Mach numbers (sufficiently high for good noise suppression) without boundary layer flow separation and with good total pressure recovery. A new method for evaluating the turbulent boundary layer was developed to separate the boundary layer from the inviscid core flow, which is characterized by a total pressure variation from hub to tip, and to determine the experimental boundary layer parameters.

Schmidt, J. F.; Ruggeri, R. S.

1976-01-01

337

Variable geometry inlet design for scram jet engine  

NASA Technical Reports Server (NTRS)

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.

Guinan, Daniel P. (Inventor); Drake, Alan (Inventor); Andreadis, Dean (Inventor); Beckel, Stephen A. (Inventor)

2005-01-01

338

Prediction of sound radiation from different practical jet engine inlets  

NASA Astrophysics Data System (ADS)

Computer codes, capable of producing accurate results for nondimensional wave numbers (based on duct radius) of up to 20, were developed and used to generate results for various other inlet configurations. Both reflection coefficients and radiation patterns were calculated by the integral solution procedure for the following five inlet configurations: the NASA Langley Bellmouth, the NASA Lewis JT-15D-1 ground test nacelle, and three hyperbolic inlets of 50, 70, and 90 degrees. Results obtained are compared with results from other experimental and theoretical studies.

Zinn, B. T.; Meyer, W. L.

339

Prediction of sound radiation from different practical jet engine inlets  

NASA Technical Reports Server (NTRS)

Computer codes, capable of producing accurate results for nondimensional wave numbers (based on duct radius) of up to 20, were developed and used to generate results for various other inlet configurations. Both reflection coefficients and radiation patterns were calculated by the integral solution procedure for the following five inlet configurations: the NASA Langley Bellmouth, the NASA Lewis JT-15D-1 ground test nacelle, and three hyperbolic inlets of 50, 70, and 90 degrees. Results obtained are compared with results from other experimental and theoretical studies.

Zinn, B. T.; Meyer, W. L.

1981-01-01

340

Heavy minerals in surficial sediments from lower Cook Inlet, Alaska  

USGS Publications Warehouse

Amphiboles, orthopyroxenes, and clinopyroxenes dominate the heavy mineral suite of surficial sediments in lower Cook Inlet, Alaska. Sources for these sediments include the igneous arc terrane of the northeast Alaska Range, reworked intrabasinal sediments, and local drainages in lower Cook Inlet. The distribution of these deposits is a reflection of both the tidal currents and the prevailing southerly net movement from the head of Cook Inlet. The heavy mineral studies concur with similar findings from gravel analyses, clay mineral investigations, and quartz microtexture observations. ?? 1984 Springer-Verlag New York Inc.

Wong, F. L.

1984-01-01

341

Investigating Liquid CO2 as a Coolant for a MTSA Heat Exchanger Design  

NASA Technical Reports Server (NTRS)

Metabolic heat regenerated Temperature Swing Adsorption (MTSA) technology is being developed for thermal and carbon dioxide (CO 2) control for a future Portable Life Support System (PLSS), as well as water recycling. CO 2 removal and rejection is accomplished by driving a sorbent through a temperature swing of approximately 210 K to 280 K . The sorbent is cooled to these sub-freezing temperatures by a Sublimating Heat Exchanger (SHX) with liquid coolant expanded to sublimation temperatures. Water is the baseline coolant available on the moon, and if used, provides a competitive solution to the current baseline PLSS schematic. Liquid CO2 (LCO2) is another non-cryogenic coolant readily available from Martian resources which can be produced and stored using relatively low power and minimal infrastructure. LCO 2 expands from high pressure liquid (5800 kPa) to Mars ambient (0.8 kPa) to produce a gas / solid mixture at temperatures as low as 156 K. Analysis and experimental work are presented to investigate factors that drive the design of a heat exchanger to effectively use this sink. Emphasis is given to enabling efficient use of the CO 2 cooling potential and mitigation of heat exchanger clogging due to solid formation. Minimizing mass and size as well as coolant delivery are also considered. The analysis and experimental work is specifically performed in an MTSA-like application to enable higher fidelity modeling for future optimization of a SHX design. In doing so, the work also demonstrates principles and concepts so that the design can be further optimized later in integrated applications (including Lunar application where water might be a choice of coolant).

Paul, Heather L.; Padilla, Sebastian; Powers, Aaron; Iacomini, Christie

2009-01-01

342

The EU advanced dual coolant blanket concept  

Microsoft Academic Search

The advanced dual coolant (A-DC) blanket is one of the EU advanced concepts to be investigated in the frame of the long-term power plant conceptual study (PPCS). Its basic concept—following the ARIES-ST concept—is based on the use of helium-cooled ferritic steel structure, the self-cooled Pb–17Li breeding zone, and SiC\\/SiC flow channel inserts. The latter serves as electrical and thermal insulators

Prachai Norajitra; Leo Bühler; Ulrich Fischer; Siegfried Malang; Gunter Reimann; Horst Schnauder

2002-01-01

343

76 FR 24513 - Public Land Order No. 7765; Partial Revocation Jupiter Inlet Lighthouse Withdrawal; Florida  

Federal Register 2010, 2011, 2012, 2013

...Land Order No. 7765; Partial Revocation Jupiter Inlet Lighthouse Withdrawal; Florida...continue to be managed as part of the Jupiter Inlet Lighthouse Outstanding Natural Area...U.S.C. 1787), which created the Jupiter Inlet Lighthouse Outstanding Natural...

2011-05-02

344

Improved core design of the high temperature supercritical-pressure light water reactor  

Microsoft Academic Search

A new coolant flow scheme has been devised to raise the average coolant core outlet temperature of the High Temperature Supercritical-Pressure Light Water Reactor (SCLWR-H). A new equilibrium core is designed with this flow scheme to show the feasibility of an SCLWR-H core with an average coolant core outlet temperature of 530°C.In previous studies, the average coolant core outlet temperature

A. Yamaji; K. Kamei; Y. Oka; S. Koshizuka

2005-01-01

345

Fiber optics for aircraft engine/inlet control  

NASA Technical Reports Server (NTRS)

NASA programs that focus on the use of fiber optics for aircraft engine/inlet control are reviewed. Fiber optics for aircraft control is attractive because of its inherent immunity to EMI and RFI noise. Optical signals can be safely transmitted through areas that contain flammable or explosive materials. The use of optics also makes remote sensing feasible by eliminating the need for electrical wires to be connected between sensors and computers. Using low-level optical signals to control actuators is also feasible when power is generated at the actuator. Each application of fiber optics for aircraft control has different requirements for both the optical cables and the optical connectors. Sensors that measure position and speed by using slotted plates can use lossy cables and bundle connectors if data transfer is in the parallel mode. If position and speed signals are multiplexed, cable and connector requirements change. Other sensors that depend on changes in transmission through materials require dependable characteristics of both the optical cables and the optical connectors. A variety of sensor types are reviewed, including rotary position encoders, tachometers, temperature sensors, and blade tip clearance sensors for compressors and turbines. Research on a gallium arsenide photoswitch for optically switched actuators that operate at 250 C is also described.

Baumbick, R. J.

1981-01-01

346

Inlet Efficiency Parameters for Supersonic Combustion Ramjet Engines.  

National Technical Information Service (NTIS)

In this report, the various definitions of inlet efficiency, which are currently in use for supersonic combustion ramjet engines, are surveyed. Derivations of each of these parameters and the relationships between them are presented. Charts for the conver...

E. T. Curran M. B. Bergsten

1964-01-01

347

Inlet total pressure loss due to acoustic wall treatment  

NASA Technical Reports Server (NTRS)

The effect of diffuser wall acoustic treatment on inlet total pressure loss was experimentally determined. Data were obtained by testing an inlet model with 10 different acoustically treated diffusers differing only in the design of the Helmholtz resonator acoustic treatment. Tests were conducted in a wind tunnel at forward velocities to 41 meters per second for inlet throat Mach numbers of .5 to .8 and angles of attack as high as 50 degrees. Results indicate a pressure loss penalty due to acoustic treatment that increases linearly with the porosity of the acoustic facing sheet. For a surface porosity of 14 percent the total pressure loss was 21 percent greater than that for an untreated inlet.

Miller, B. A.

1977-01-01

348

Particle Trajectory Computation on a 3-Dimensional Engine Inlet.  

National Technical Information Service (NTIS)

A 3-dimensional particle trajectory computer code was developed to compute the distribution of water droplet impingement efficiency on a 3-dimensional engine inlet. The computed results provide the essential droplet impingement data required for the engin...

J. J. Kim

1986-01-01

349

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

Code of Federal Regulations, 2013 CFR

...tank used for the transportation of liquefied materials to permit complete drainage. (2) Except for gauging devices, thermometer wells, pressure relief valves, manhole openings, product inlet openings, and product discharge openings, each...

2013-10-01

350

45. VIEW UPSTREAM AT FOREBAY, INLET GATES, PIT GATES AND ...  

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

45. VIEW UPSTREAM AT FOREBAY, INLET GATES, PIT GATES AND TRASH RACKS. Taken by Jet Lowe, HAER staff photographer, September 1980 - Dam No. 5 Hydroelectric Plant, On Potomac River, Hedgesville, Berkeley County, WV

351

INTERIOR RADIO BEACON ROOM, LOOKING NORTHEAST. Oregon Inlet Coast ...  

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

INTERIOR RADIO BEACON 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

352

PIE Nacelle Flow Analysis and TCA Inlet Flow Quality Assessment  

NASA Technical Reports Server (NTRS)

This presentation includes three topics: (1) Analysis of isolated boattail drag; (2) Computation of Technology Concept Airplane (TCA)-installed nacelle effects on aerodynamic performance; and (3) Assessment of TCA inlet flow quality.

Shieh, C. F.; Arslan, Alan; Sundaran, P.; Kim, Suk; Won, Mark J.

1999-01-01

353

VIEW OF MORTARED ROCK AND CONCRETE INLET TO COUCH LATERAL ...  

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

VIEW OF MORTARED ROCK AND CONCRETE INLET TO COUCH LATERAL CANAL, UPSTREAM OF COLLINS ROAD. LOOKING NORTH/NORTHEAST - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

354

CFD Results for an Axisymmetric Isentropic Relaxed Compression Inlet  

NASA Technical Reports Server (NTRS)

The OVERFLOW code was used to calculate the flow field for a family of five relaxed compression inlets, which were part of a screening study to determine a configuration most suited to the application of microscale flow control technology as a replacement for bleed. Comparisons are made to experimental data collected for each of the inlets in the 1- by 1-Foot Supersonic Wind Tunnel at the NASA Glenn Research Center (GRC) to help determine the suitability of computational fluid dynamics (CFD) as a tool for future studies of these inlets with flow control devices. Effects on the wind tunnel results of the struts present in a high subsonic flow region accounted for most of the inconsistency between the results. Based on the level of agreement in the present study, it is expected that CFD can be used as a tool to aid in the design of a study of this class of inlets with flow control.

Hirt, Stefanie M.; Tacina, Kathleen M.; Conners, Timothy R.; Merret, Jason M.; Howe, Donald C.

2008-01-01

355

Aerodynamic and acoustic performance of high Mach number inlets  

NASA Technical Reports Server (NTRS)

Experimental results were obtained for two types of high Mach number inlets, one with a translating centerbody and one with a fixed geometry (collapsing cowl) without centerbody. The aerodynamic and acoustic performance of these inlets was examined. The effects of several parameters such as area ratio and length-diameter ratio were investigated. The translating centerbody inlet was found to be superior to the collapsing cowl inlet 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 parameter to be more significant. Also, greater high frequency noise attenuation was achieved by increasing Mach number from low to high subsonic values.

Lumsdaine, E.; Clark, L. R.; Cherng, J. C.; Tag, I.

1977-01-01

356

Wave-driven fluxes through New River Inlet, NC  

NASA Astrophysics Data System (ADS)

The importance of wave forcing to inlet circulation is examined using observations of waves, water levels, and currents collected in and near New River Inlet, NC during April and May, 2012. A boat-mounted system was used to measure current profiles along transects across the inlet mouth during three 14-hr periods, providing information on cross-inlet current structure, as well as discharge. Additionally, an array of 13 colocated pressure gages and profilers were deployed along 2 km of the inlet channel (5 to 10 m water depths) and ebb shoal channel (2 to 3 m water depths) and 19 colocated pressure gages and acoustic Doppler velocimeters were deployed across and offshore of the ebb shoal (1 to 5 m water depths) (Figure 1). The inlet is well mixed and tidal currents ranged from +/- 1.5 m/s, maximum discharge rates at peak ebb and flood were about 700 to 900 m3/s, offshore significant wave heights Hsig were 0.5 to 2.5 m, and wind speeds ranged from 0 to 14 m/s. Time-integrated residual discharge over semi-diurnal tidal cycles with similar ranges was ebb dominant during calm conditions (May 11, net out-of-inlet discharge ~ 55 m3, Hsig ~ 0.5 m, NW winds ~ 3 m/s) and flood dominant during stormier conditions (May 14, net into-inlet discharge ~ 15 m3, Hsig ~ 1.2 m, S winds ~ 6.5 m/s). Low-pass filtered in situ profiler data suggest wave-forcing affects the fluxes into and out of the inlet. The observations will be used to examine the momentum balance governing the temporal and cross-inlet (channel vs. shoal) variation of these fluxes, as well as the effect of waves on ebb and flood flow dominance. Funding provided by the Office of Naval Research and a National Security Science and Engineering Faculty Fellowship.; Figure 1: Google Earth image of New River Inlet, NC. Colors are depth contours (scale on the right, units are m relative to mean sea level) and symbols are locations of colocated current meters and pressure gages.

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

2012-12-01

357

A multidisciplinary optimization method for designing boundary layer ingesting inlets  

Microsoft Academic Search

The Blended-Wing-Body is a conceptual aircraft design with rear-mounted, over-wing engines. Two types of engine installations have been considered for this aircraft. One installation is quite conventional with podded engines mounted on pylons. The other installation has partially buried engines with boundary layer ingesting inlets. Although ingesting the low-momentum flow in a boundary layer can improve propulsive efficiency, poor inlet

David Leonard Rodriguez

2001-01-01

358

Experimental Investigation of Actuators for Flow Control in Inlet Ducts  

NASA Astrophysics Data System (ADS)

Attractive to aircraft designers are compact inlets, which implement curved flow paths to the compressor face. These curved flow paths could be employed for multiple reasons. One of which is to connect the air intake to the engine embedded in the aircraft body. A compromise must be made between the compactness of the inlet and its aerodynamic performance. The aerodynamic purpose of inlets is to decelerate the oncoming flow before reaching the engine while minimizing total pressure loss, unsteadiness and distortion. Low length-to-diameter ratio inlets have a high degree of curvature, which inevitably causes flow separation and secondary flows. Currently, the length of the propulsion system is constraining the overall size of Unmanned Air Vehicles (UAVs), thus, smaller more efficient aircrafts could be realized if the propulsion system could be shortened. Therefore, active flow control is studied in a compact (L/D=1.5) inlet to improve performance metrics. Actuation from a spanwise varying coanda type ejector actuator and a hybrid coanda type ejector / vortex generator jet actuator is investigated. Special attention will be given to the pressure recovery at the AIP along with unsteady pressure signatures along the inlet surface and at the AIP.

Vaccaro, John; Elimelech, Yossef; Amitay, Michael

2010-11-01

359

Experimental Investigation of Actuators for Flow Control in Inlet Ducts  

NASA Astrophysics Data System (ADS)

For military applications, inlet designs are constrained by low observability requirements, which call for the use of an S-duct inlet. The inlets purpose is to limit the line-of-sight to the compressor and decelerate the incoming flow while minimizing total pressure loss, distortion, and unsteadiness. In addition, in unmanned aerial vehicles, the inlet length can determine the overall size of the aircraft. For this reason, aggressive inlets can have a large impact on overall system efficiency. Experiments have been conducted which evaluate the effectiveness of different actuation systems for active flow control in an aggressive S-duct inlet, L/D = 1.5 (at flow conditions representative of flight conditions). Comparisons will be made between: steady and unsteady blowing from a single 2-D tangential slit, spanwise varying injection from a tangential slit, and spanwise varying injection of a hybrid actuator that has both a coanda type injector along with vortex generator jets to eliminate vorticity developed by secondary flow inherent to S-ducts. Evaluations criteria will include total pressure recovery, AIP distortion levels, and unsteady pressure fluctuations.

Vaccaro, John; Amitay, Michael

2009-11-01

360

Sediment distribution and coastal processes in Cook Inlet, Alaska  

NASA Technical Reports Server (NTRS)

Regional hydrologic and oceanographic relationships in Cook Inlet, Alaska have been recognized from sequential ERTS-1 MSS imagery. Current patterns are visible in the inlet because of differential concentrations of suspended sediment. The circulation patterns within Cook Inlet are controlled primarily by the interaction between the semi-diurnal tides and the counter clockwise Alaska current. In general, heavily sediment laden water is seen to be confined to portions of the inlet north of the Forelands and west of Kalgin Island. Tongues of clear oceanic water are observed to enter the inlet through Kennedy Channel along the east shoreline in the vicinity of Cape Elizabeth. A recurring counterclockwise circulation pattern observed around Kalgin Island seems to result from the interplay of the northerly moving water along the east shore and the southerly moving, sediment laden, water along the west side of the inlet. Prominent, fresh water plumes, heavily laden with sediment are visible at the mouths of all major rivers. Relect plumes from as many as three tidal stages have been recognized.

Anderson, D. M.; Gatto, L. W.; Mckim, H. L.; Petrone, A.

1973-01-01

361

Inlet Flow Control and Prediction Technologies for Embedded Propulsion Systems  

NASA Technical Reports Server (NTRS)

Fail-safe, hybrid, flow control (HFC) is a promising technology for meeting high-speed cruise efficiency, low-noise signature, and reduced fuel-burn goals for future, Hybrid-Wing-Body (HWB) aircraft with embedded engines. This report details the development of HFC technology that enables improved inlet performance in HWB vehicles with highly integrated inlets and embedded engines without adversely affecting vehicle performance. In addition, new test techniques for evaluating Boundary-Layer-Ingesting (BLI)-inlet flow-control technologies developed and demonstrated through this program are documented, including the ability to generate a BLI-like inlet-entrance flow in a direct-connect, wind-tunnel facility, as well as, the use of D-optimal, statistically designed experiments to optimize test efficiency and enable interpretation of results. Validated improvements in numerical analysis tools and methods accomplished through this program are also documented, including Reynolds-Averaged Navier-Stokes CFD simulations of steady-state flow physics for baseline, BLI-inlet diffuser flow, as well as, that created by flow-control devices. Finally, numerical methods were employed in a ground-breaking attempt to directly simulate dynamic distortion. The advances in inlet technologies and prediction tools will help to meet and exceed "N+2" project goals for future HWB aircraft.

McMillan, Michelle L.; Mackie, Scott A.; Gissen, Abe; Vukasinovic, Bojan; Lakebrink, Matthew T.; Glezer, Ari; Mani, Mori; Mace, James L.

2011-01-01

362

Large-Scale Low-Boom Inlet Test Overview  

NASA Technical Reports Server (NTRS)

This presentation provides a high level overview of the Large-Scale Low-Boom Inlet Test and was presented at the Fundamental Aeronautics 2011 Technical Conference. In October 2010 a low-boom supersonic inlet concept with flow control was tested in the 8'x6' supersonic wind tunnel at NASA Glenn Research Center (GRC). The primary objectives of the test were to evaluate the inlet stability and operability of a large-scale low-boom supersonic inlet concept by acquiring performance and flowfield validation data, as well as evaluate simple, passive, bleedless inlet boundary layer control options. During this effort two models were tested: a dual stream inlet intended to model potential flight hardware and a single stream design to study a zero-degree external cowl angle and to permit surface flow visualization of the vortex generator flow control on the internal centerbody surface. The tests were conducted by a team of researchers from NASA GRC, Gulfstream Aerospace Corporation, University of Illinois at Urbana-Champaign, and the University of Virginia

Hirt, Stefanie

2011-01-01

363

Computational study of inlet injection for a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine  

NASA Technical Reports Server (NTRS)

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.

Gonzalez, D. E.

1995-01-01

364

Preparation, conduct, and experimental results of the AVR loss-of-coolant accident simulation test  

Microsoft Academic Search

A loss-of-coolant accident (LOCA) is one of the most severe accidents for a nuclear power plant. To demonstrate inherent safety characteristics incorporated into small high-temperature gas-cooled reactor (HTGR) design, LOCA simulation tests have been conducted at the Arbeitsgemeinschaft Versuchsreaktor (AVR), the German pebble-bed-high-temperature reactor plant. The AVR is the only nuclear power plant ever to have been intentionally subjected to

K. Kruger; A. Bergerfurth; S. Burger; P. Pohl; M. Wimmers; J. C. Cleveland

1991-01-01

365

Electro-impulse de-icing of a turbofan engine inlet  

NASA Technical Reports Server (NTRS)

The application of electromagnetic impulse deicing (EIDI) systems to turbofan engine inlets on business aircraft has been investigated experimentally. The tests were performed in the Icing Research Tunnel at NASA's Lewis Research Center. The deicing system testbed was a Falcon Fanjet 20 engine nacelle. The effectiveness of various deicing coil configurations and mount designs were compared, and design parameters were developed specifically for EIDI systems in turbofan engines. Flight tests were also carried out at altitudes in the range 3000-6000 ft corresponding to a temperature range of -3 to -8 C. It is shown that the ice particles removed from the engine inlet by the deicing system were small enough for the engine to ingest. Tentative design specifications are given with respect to the optimum coil configuration, and operating power of a EIDI production candidate.

Zumwalt, G. W.

1985-01-01

366

Control of reactor coolant flow path during reactor decay heat removal  

DOEpatents

An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

Hunsbedt, Anstein N. (Los Gatos, CA)

1988-01-01

367

Application of rotor mounted pressure transducers to analysis of inlet turbulence. [flow distortion in turbofan engine inlet  

NASA Technical Reports Server (NTRS)

Miniature pressure transducers installed near the leading edge of a fan blade were used to diagnose the non-uniform flow entering a subsonic tip speed turbofan on a static test stand. The pressure response of the blade to the inlet flow variations was plotted in a form which shows the space-time history of disturbances ingested by the rotor. Also, periodically sampled data values were auto- and cross-correlated as if they had been acquired from fixed hot wire anemometers at 150 equally spaced angles around the inlet. With a clean inlet and low wind, evidence of long, narrow turbulence eddies was easily found both in the boundary layer of the fan duct and outside the boundary layer. The role of the boundary layer was to follow and amplify disturbances in the outer flow. These eddies frequently moved around the inlet with a corkscrew motion as they passed through.

Hanson, D. B.

1976-01-01

368

Analysis of an advanced ducted propeller subsonic inlet  

NASA Technical Reports Server (NTRS)

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; however, with the fixed flow properties BC, a good comparison with the test data was obtained.

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

1992-01-01

369

Optimum power boosting of gas turbine cycles with compressor inlet air refrigeration  

SciTech Connect

A conceptual gas turbine cycle with refrigerated air supplied to the compressor inlet is proposed to increase the cycle specific net power significantly and render it practically insensitive to seasonal temperature fluctuations. It is optimized for maximum power per m{sup 3}/s and maximum power per kg/s of induced air. These cycle performances are evaluated in a numerical example for two refrigeration cycle efficiencies, based on state-of-the-art isentropic efficiency coefficients of the compressor and turbine. The specific heats of air and products of combustion are treated as temperature-dependent parameters to be determined as integrated mean averages.

Ait-Ali, M.A. [Ecole Nationale Polytechnique, Alger (Algeria)]|[Ecole Centrale-Paris, Chatenay-Malabry (France)

1997-01-01

370

Cryogenic-coolant He-4-superconductor interaction  

NASA Technical Reports Server (NTRS)

The thermodynamic and thermal interaction between a type 2 composite alloy and cryo-coolant He4 was studied with emphasis on post quench phenomena of formvar coated conductors. The latter were investigated using a heater simulation technique. Overall heat transfer coefficients were evaluated for the quench onset point. Heat flux densities were determined for phenomena of thermal switching between a peak and a recovery value. The study covered near saturated liquid, pressurized He4, both above and below the lambda transition, and above and below the thermodynamic critical pressure. In addition, friction coefficients for relative motion between formvar insulated conductors were determined.

Caspi, S.; Lee, J. Y.; Kim, Y. I.; Allen, R. J.; Frederking, T. H. K.

1978-01-01

371

Nuclear fuel assembly with coolant conducting tube  

SciTech Connect

In a nuclear fuel assembly having a coolant conducting or water tube which also retains the spacers in axial position, the fuel rods experience greater axial growth with exposure than the water tube creating a risk that the water tube might become disengaged from the supporting tie plates. An arrangement for preventing such disengagement is described including lengthened end plug shanks for the water tube, a protective boss surrounding the lower end plug shank to protect it from flow induced vibration, a conical seat for the lower end plug and an arrangement for limiting upward movement of the water tube.

Dunlap, T. G.; Cearley, J. E.; Jameson, W. G. Jr.; Mefford, C. R.; Nelson, H. L.

1983-12-13

372

Tidal Wave Characteristics and Water Quality Response at New River Inlet, NC  

NASA Astrophysics Data System (ADS)

In the spring 2012, a multi-institutional collaborative field experiment (RIVET) was performed at New River Inlet (NRI), NC. A wide range of instrumentation was used to measure winds, tides, mean sea-surface levels, waves, currents, salinity, temperature, ocean color, water quality, and the bathymetry from offshore of the ebb shoal to the mouth of the inlet to along the inlet channel and into the estuary. A brief overview of the collaborative effort will be presented, followed by a discussion of tidal propagation from the ocean to the back-bay estuary and the Intra Coastal Waterway (ICW), and the corresponding effect on water quality and optical properties. NRI is a shallow-water, frictional estuary that connects the ocean via a 5 km long, narrow channel to the back bay. NRI is considered a "choked" inlet due to the small cross-sectional area, long channel, and large storage of the back bay. In contrast to many inlets on the east coast of the US, owing to the morphologic choking the ebb and flood dominance at the entrance is primarily controlled by the modulation (MSF, K1, O1) of the M2 oceanic forcing. However, farther upstream the system becomes flood-dominated owing to the bathymetric configuration. The transition zone, located at the upper extent of the tidal excursion, is near the channel exit within the back bay and features tidal intrusion fronts. The ICW intersection with the inlet channel influences the mixing and exchange of the NRI system and neighboring inlets. The flow measured in the ICW at 1 km south of the ICW intersection is in phase with the flow in the primary NRI channel and is independent of the inlet 36 km to the south. In contrast, the flow 1 km north of the ICW intersection primarily is controlled by the inlet 12 km to the north, resulting in a phase lag with the flow in the primary NRI channel. Ocean-derived water is prevalent in the northern ICW, whereas higher levels of colored dissolved organic matter and salinities are found in the southern ICW associated with the marshes, shallow bays, and small channels. Owing to the confluence of the ICW, frontal patterns are observed in the center of the channel. During the ebb flows, these fronts oscillate across the channel as they propagate downstream. The tidal modulation of water quality and optical properties will be discussed in relation to the flow behavior. The detailed in situ field observations of NRI allow for extensive evaluation of numerical models for tidal propagation and three-dimensional tidal mixing, tidal exchange, and residence times, as well as for material transport and water quality. In addition, the in situ observations provide a rich data set for ground truth for the simultaneous remote sensing studies (DARLA), as well as data to initialize, to assimilate into, and to test models that invert for the underlying bathymetry. Funding was provided by the Office of Naval Research.

MacMahan, J. H.; Reniers, A. J.; Weltmer, M.; Rynne, P. F.; Van De Kreeke, J.; Thornton, E. B.; Brown, J.; Raubenheimer, B.; Elgar, S.; Feddersen, F.; Guza, R. T.; Milligan, T.

2012-12-01

373

Analysis of coolant flow and heat transfer in the SSME HPOTP Number 4 bearing assembly  

NASA Technical Reports Server (NTRS)

The PHOENICS code has been applied to simulate the flow of liquid oxygen through the number 4 ball bearing assembly of the Space Shuttle Main Engine High-Pressure Oxidizer Turbopump. The Body-Fitted Coordinate system capability of PHOENICS was utilized to create a geometrically accurate model. Effects accounted for by the model include the rotation rate of the calculation domain, viscous heating in the liquid oxygen and two-phase effects due to LOX boiling. A separation program was used to account for conduction within a ball bearing element which was coupled with the PHOENICS flow and heat transfer analysis. Solutions have been obtained for the velocity and temperature fields within the LOX coolant and the temperature within the ball element. The predicted ball temperatures indicate that the coolant is boiling in the region near the ball surface.

Owens, S. F.; Costes, N. C.

1990-01-01

374

Control of Inflow Distortion in a Scarf Inlet  

NASA Technical Reports Server (NTRS)

The scarf inlet has the potential to reduce aircraft inlet noise radiation to the ground by reflecting it into the space above the engine. Without forward motion of the engine, the non-symmetry of the inlet causes inflow distortion which generates noise that is greater than the noise reduction of the scarf. However, acoustic evaluations of aircraft engines are often done on static test stands. A method to reduce inflow distortion by boundary layer suction is proposed and evaluated using a model of a high bypass ratio engine located in an anechoic chamber. The design goal of the flow control system is to make the inflow to the inlet circumferentially uniform and to eliminate reversed flow. This minimizes the inflow distortion and allows for acoustic evaluation of the scarf inlet on a static test stand. The inlet boundary layer suction effectiveness is evaluated both by aerodynamic and by acoustic measurements. Although the design goal is not met, the control system is found to have a beneficial effect on the engine operation, reducing blade stall and speed variation. This is quantified by two acoustic benefits, reduction both of the variability of tone noise and of the low frequency wideband noise due to the inflow distortion. It is felt that a compromise in the manufacture of the control hardware contributes to the inability of the control system to perform as expected from the analysis. The control system with sufficient authority is felt to have the potential to permit reliable acoustic testing in a static configuration of engines with non-symmetric inlets. Because the control system can improve operation of the engine, it may also have the potential to reduce noise and vibration and enhance engine longevity during low speed ground operations in the terminal area.

Gerhold, Carl H.; Clark, Lorenzo R.; Biedron, Robert T.

2002-01-01

375

Active Flow Control on a Boundary-Layer-Ingesting Inlet  

NASA Technical Reports Server (NTRS)

Boundary layer ingestion (BLI) is explored as means to improve overall system performance for Blended Wing Body configuration. The benefits of BLI for vehicle system performance benefit are assessed with a process derived from first principles suitable for highly-integrated propulsion systems. This performance evaluation process provides framework within which to assess the benefits of an integrated BLI inlet and lays the groundwork for higher-fidelity systems studies. The results of the system study show that BLI provides a significant improvement in vehicle performance if the inlet distortion can be controlled, thus encouraging the pursuit of active flow control (AFC) as a BLI enabling technology. The effectiveness of active flow control in reducing engine inlet distortion was assessed using a 6% scale model of a 30% BLI offset, diffusing inlet. The experiment was conducted in the NASA Langley Basic Aerodynamics Research Tunnel with a model inlet designed specifically for this type of testing. High mass flow pulsing actuators provided the active flow control. 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 was determined by 120 total pressure measurements located at the aerodynamic interface plane. The test matrix was limited to a maximum freestream Mach number of 0.15 with scaled mass flows through the inlet for that condition. The data show that the pulsed actuation can reduce distortion from 29% to 4.6% as measured by the circumferential distortion descriptor DC60 using less than 1% of inlet mass flow. Closed loop control of the actuation was also demonstrated using a sidewall surface static pressure as the response sensor.

Gorton, Susan Althoff; Owens, Lewis R.; Jenkins, Luther N.; Allan, Brian G.; Schuster, Ernest P.

2004-01-01

376

Organics Verification Study for Sinclair and Dyes Inlets, Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. Because significant cleanup and source control activities have been conducted in the inlets since the data supporting the 1998 303(d) listings were collected, two verification studies were performed to address the 303(d) segments that were listed for metal and organic contaminants in marine sediment. The Metals Verification Study (MVS) was conducted in 2003; the final report, Metals Verification Study for Sinclair and Dyes Inlets, Washington, was published in March 2004 (Kohn et al. 2004). This report describes the Organics Verification Study that was conducted in 2005. The study approach was similar to the MVS in that many surface sediment samples were screened for the major classes of organic contaminants, and then the screening results and other available data were used to select a subset of samples for quantitative chemical analysis. Because the MVS was designed to obtain representative data on concentrations of contaminants in surface sediment throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, aliquots of the 160 MVS sediment samples were used in the analysis for the Organics Verification Study. However, unlike metals screening methods, organics screening methods are not specific to individual organic compounds, and are not available for some target organics. Therefore, only the quantitative analytical results were used in the organics verification evaluation. The results of the Organics Verification Study showed that sediment quality outside of Sinclair Inlet is unlikely to be impaired because of organic contaminants. Similar to the results for metals, in Sinclair Inlet, the distribution of residual organic contaminants is generally limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard and Intermediate Maintenance Facility Superfund Site, where further source-control actions and monitoring are under way.

Kohn, Nancy P.; Brandenberger, Jill M.; Niewolny, Laurie A.; Johnston, Robert K.

2006-09-28

377

Coolant mixing and distribution in a transparent reactor model  

Microsoft Academic Search

Following a small break loss-of-coolant accident in a pressurized water reactor, coolant water may be injected at high pressure to help cool the core. This paper reports the results of tests which determined the mixing and distribution of the coolant in a 1\\/5-scale transparent model of the reactor. The model components included the reactor vessel, cold leg pipe, pump, and

M. W. Fanning; G. Haury; L. Pflug; P. H. Rothe

1983-01-01

378

Porous coolant tube holder for fuel cell stack  

DOEpatents

A coolant tube holder for a stack of fuel cells is a gas porous sheet of fibrous material adapted to be sandwiched between a cell electrode and a nonporous, gas impervious flat plate which separates adjacent cells. The porous holder has channels in one surface with coolant tubes disposed therein for carrying coolant through the stack. The gas impervious plate is preferably bonded to the opposite surface of the holder, and the channel depth is the full thickness of the holder.

Guthrie, Robin J. (East Hartford, CT)

1981-01-01

379

Effect of the inlet configuration on the inner airflow distribution uniformity of the bag filter  

Microsoft Academic Search

The gas flow fields of the bag filter with different inlet configurations (one perpendicular inlet, double perpendicular inlets and double inclined inlets) were simulated by means of computational fluid dynamics (CFD) technology in this study, and the velocity field?» the flow rate distribution coefficient across each bag in the bag filter of three simulation cases were calculated. The results indicate

Fuping Qian; Yuqi Ye

2011-01-01

380

Inlet performance of the integrated Langley scramjet module  

NASA Technical Reports Server (NTRS)

The inlet concept for the Langley Scramjet Module has been developed and proven in Langley wind tunnels over a Mach number range from 2.3 to 6.0 (flight simulation of Mach 2.6 to 7.6). This modular engine concept is designed to integrate with the airframe, which results in precompression of the engine airflow by the vehicle bow shock and additional expansion of the nozzle exhaust gas by the afterbody of the vehicle. With these integration advantages, the inlet can be designed with modest contraction ratios and fixed geometry. Also, the module nozzle exit area can be equal to the capture area, which permits the cowl to be alined with the local flow producing minimum external drag. The inlet leading edges and planar compression surfaces are swept at 48 deg, which provides spillage at low Mach numbers for starting and which reduces the pressure gradient on the top surface to permit ingestion of the vehicle forebody boundary layer into the inlet without separating. Three fuel injection struts provide for the use of a short combustor having low internal cooling requirements. Schedules for mass capture ratio, contraction ratio, and total pressure recovery are well within the acceptable range for a good scramjet propulsion device. The fixed geometry, minimum external drag design has proven to be a practical, high-performance inlet concept.

Trexler, C. A.

1975-01-01

381

Detailed investigation of flowfields within large scale hypersonic inlet models  

NASA Technical Reports Server (NTRS)

Analytical and experimental investigations were conducted to determine the characteristics of the internal flows in model passages representative of hypersonic inlets and also sufficiently large for meaningful data to be obtained. Three large-scale inlet models, each having a different compression ratio, were designed to provide high performance and approximately uniform static-pressure distributions at the throat stations. A wedge forebody was used to simulate the flowfield conditions at the entrance of the internal passages, thus removing the actual vehicle forebody from consideration in the design of the wind-tunnel models. Tests were conducted in a 3.5 foot hypersonic wind tunnel at a nominal test Mach number of 7.4 and freestream unit Reynolds number of 2,700,000 per foot. From flowfield survey data the inlet entrance, the entering inviscid and viscous flow conditions were determined prior to the analysis of the data obtained in the internal passages. Detailed flowfield survey data were obtained near the centerlines of the internal passages to define the boundary-layer development on the internal surfaces and the internal shock-wave configuration. Finally, flowfield data were measured across the throats of the inlet models to evaluate the internal performance of the internal passages. These data and additional results from surface instrumentation and flow visualization studies were utilized to determine the internal flowfield patterns and the inlet performance.

Seebaugh, W. R.; Doran, R. W.; Decarlo, J. P.

1971-01-01

382

Advanced Scour Monitoring at Indian River Inlet, Delaware  

NASA Astrophysics Data System (ADS)

The scour holes threatening the bridge over Indian River Inlet, Delaware are unique in their size and location, and thus demand an innovative approach to their observation. Typical bridge scour occurs at the base of support structures. However, scour at Indian River Inlet has developed two large holes over 25m deep that flank the bridge. The deepest part of one hole sits just 45m away from the bridge foundation, and has been migrating toward the bridge at a rate that has alarmed Delaware Department of Transportation (DelDOT) engineers. Recently a real-time bridge and bathymetric monitoring system was installed, giving engineers the ability to make operational decisions regarding the safety of the bridge, and providing scientists a unique opportunity to investigate the coupled inlet morphologic evolution and hydrodynamics over multiple time scales. The monitoring system consists of two identical sets of instruments permanently mounted to subaqueous bridge piers, with one three dimensional imaging sonar and one horizontal ADCP comprising each pair. This new system represents significant progress in scour monitoring at Indian River Inlet. Previous efforts only provided snapshots of the storied evolution of the bathymetry or tidal forcing - and thus offered diminished potential for understanding the complicated inlet dynamics. Data from the instruments are automatically uploaded to University of Delaware servers and processed twice per day. Preliminary analysis of observed diurnal evolution in bathymetry along with associated forcing will be presented.

Hayden, J. T.; Puleo, J. A.; Macmahan, J. H.

2008-12-01

383

Development of the Planar Inlet Design and Analysis Process (PINDAP)  

NASA Technical Reports Server (NTRS)

The aerodynamic development of an engine inlet requires a comprehensive program of both wind tunnel testing and Computational Fluid Dynamics (CFD) simulations. To save time and resources, much "testing" is done using CFD before any design ever enters a wind tunnel. The focus of my project this summer is on CFD analysis tool development. In particular, I am working to further develop the capabilities of the Planar Inlet Design and Analysis Process (PINDAP). "PINDAP" is a collection of computational tools that allow for efficient and accurate design and analysis of the aerodynamics about and through inlets that can make use of a planar (two-dimensional or axisymmetric) geometric and flow assumption. PINDAP utilizes the WIND CFD flow solver, which is capable of simulating the turbulent, compressible flow field. My project this summer is a continuation of work that I performed for two previous summers. Two years ago, I used basic features of the PINDAP to design a Mach 5 hypersonic scramjet engine inlet and to demonstrate the feasibility of the PINDAP. The following summer, I worked to develop its geometry and grid generation capabilities to include subsonic and supersonic inlets, complete bodies and cowls, conic leading and trailing edges, as well as airfoils. These additions allowed for much more design flexibility when using the program.

Gruber, Christopher R.

2004-01-01

384

Improved Inlet Noise Attenuation by Alteration of Boundary Layer Profiles  

NASA Technical Reports Server (NTRS)

Acoustic liners are an essential component of technology used to reduce aircraft engine noise. Flow affects attenuation due to the liner in several ways, one of which is that boundary layers adjacent to the liner refract the sound. In the case of inlet noise, the boundary layer causes sound to be refracted away from the liner, thus degrading attenuation. A concept to improve attenuation by the liner by alteration of inlet boundary layer profiles is presented. The alteration of profiles is achieved by inlet blowing. Computational fluid dynamics and duct mode propagation theory for ducts carrying a parallel sheared flow have been used to design experiments to explore such a possibility in the NASA Langley Research Center Grazing Incidence Tube using an inlet blowing scheme developed at General Electric Global Research. The effects of inlet blowing on two liner configurations were evaluated. Calculated results will be shown for blowing ratios (injected flow/duct flow) of approximately 12% and frequencies up to 3 kHz. These results emphasize changes of attenuation achieved by blowing for the two liners. Experimental results of measured flow profiles (with and without blowing) in the Grazing Incidence Tube, and of corresponding changes in attenuation by the liner due to blowing will be presented.

Mani, Ramani; Luedke, Jon; Jones, Michael G.; Nark, Douglas M.

2004-01-01

385

Numerical Analysis of the Trailblazer Inlet Flowfield for Hypersonic Mach Numbers  

NASA Technical Reports Server (NTRS)

A study of the Trailblazer vehicle inlet was conducted using the Global Air Sampling Program (GASP) code for flight Mach numbers ranging from 4-12. Both perfect gas and finite rate chemical analysis were performed with the intention of making detailed comparisons between the two results. Inlet performance was assessed using total pressure recovery and kinetic energy efficiency. These assessments were based upon a one-dimensional stream-thrust-average of the axisymmetric flowfield. Flow visualization utilized to examine the detailed shock structures internal to this mixed-compression inlet. Kinetic energy efficiency appeared to be the least sensitive to differences between the perfect gas and finite rate chemistry results. Total pressure recovery appeared to be the most sensitive discriminator between the perfect gas and finite rate chemistry results for flight Mach numbers above Mach 6. Adiabatic wall temperature was consistently overpredicted by the perfect gas model for flight Mach numbers above Mach 4. The predicted shock structures were noticeably different for Mach numbers from 6-12. At Mach 4, the perfect gas and finite rate chemistry models collapse to the same result.

Steffen, C. J., Jr.; DeBonis, J. R.

1999-01-01

386

Three-dimensional turbulent-mixing-length modeling for discrete-hole coolant injection into a crossflow  

NASA Technical Reports Server (NTRS)

Three dimensional mixing length models of a flow field immediately downstream of coolant injection through a discrete circular hole at a 30 deg angle into a crossflow were derived from the measurements of turbulence intensity. To verify their effectiveness, the models were used to estimate the anisotropic turbulent effects in a simplified theoretical and numerical analysis to compute the velocity and temperature fields. With small coolant injection mass flow rate and constant surface temperature, numerical results of the local crossflow streamwise velocity component and surface heat transfer rate are consistent with the velocity measurement and the surface film cooling effectiveness distributions reported in previous studies.

Wang, C. R.; Papell, S. S.

1983-01-01

387

Corrugated and Composite Nozzle-Inlets for Thrust and Noise Benefits  

NASA Technical Reports Server (NTRS)

The following research results are based on development of an approach previously proposed and investigated in for optimum nozzle design to obtain maximum thrust. The design was denoted a Telescope nozzle. A Telescope nozzle contains one or several internal designs, which are inserted at certain locations into a divergent conical or planar main nozzle near its exit. Such a design provides additional thrust augmentation over 20% by comparison with the optimum single nozzle of equivalent lateral area, What is more, experimental acoustic tests have discovered an essential noise reduction due to application of Telescope nozzles. In this paper, some additional theoretical results are presented for Telescope nozzles and a similar approach is applied for aero-performance improvement of a supersonic inlet. Numerical simulations were conducted for supersonic flow into the divergent portion of a 2D or axisymmetric nozzle with several plane or conical designs as well as into a 2D or axisymmetric supersonic inlet with a forebody. The Kryko-Godunov marching numerical scheme for inviscid supersonic flows was used. Several cases were tested using the NASA CFL3d and IM/MSU Russian codes based on the full Navier-Stokes equations. Numerical simulations were conducted for non reacting flows (both codes) as well as for real high temperature gas flows with non-equilibrium chemical reactions (the latter code). In general, these simulations have confirmed essential benefits of Telescope design applications in propulsion system. Some preliminary numerical simulations of several typical inlet designs were conducted with the goal of inlet design optimization for maneuvering flight conditions.

Gilinsky, M.; Blankson, I. M.; Gromov, V. G.; Sakharov, V. I.

2004-01-01

388

Desensitization of over tip leakage in an axial turbine rotor by tip surface coolant injection  

NASA Astrophysics Data System (ADS)

Mechanical energy extraction in axial flow turbine rotors occurs through a change in angular momentum of the working fluid. The gap between the turbine rotor and the stationary casing is referred to as the tip gap. High pressure turbine blades are typically un-shrouded and pressure driven flow through the tip gap is termed as over tip leakage. Over tip leakage reduces efficiency of the turbine stage and also causes thermal distress to blade tip surfaces. The gap height typically increases over the operational life of a turbine, leading to increased efficiency drop. The thermal load on the tip surface also increases with increasing gap height and is exacerbated by the radial transport of high temperature fluid found in the core of the combustor exit flow. Thus over tip leakage not only decreases stage efficiency, but also constrains it by limiting the maximum cycle temperature. Reducing the sensitivity of turbine performance to the effects of the tip gap is termed Tip Desensitization. An experimental investigation of tip desensitization through coolant injection from a tip surface trench was conducted in a large scale, low speed, rotating research turbine facility. Five out of twenty nine rotor blades, referred to as cooled blades, are provided with coolant injection at four locations, at 61%, 71%, 81%, and 91% blade tip axial chord length. At each of the first three locations the coolant jets are directed towards the blade pressure-side, while coolant is exhausted radially at the last location. The sensitivity of total pressure defect, due to over tip leakage, to tip gap height is reduced by both coolant injection and roughening of the casing surface. The total pressure defect due to the large gap height of 1.40% blade height is reduced to levels comparable to the defect due to a gap height of 0.72% blade height. The strong total pressure gradient that characterizes the leakage vortex due to the gap height of 1.40% blade height is considerably diminished by both coolant injection and roughening of the casing surface. Coolant injection from 81% chord location is most effective in reducing both the total pressure defect and the total pressure gradient. Casing surface roughness significantly shifts the leakage vortex towards blade suction surface reducing its interaction with the upper passage vortex. The benefit of casing surface roughness is greater at larger gap heights. (Abstract shortened by UMI.)

Rao, Nikhil Molahally

389

Experimental investigation on the moving characteristics of molten metal droplets impacting coolant  

SciTech Connect

This paper reports the results of an experimental investigation on the moving characteristics of molten metal droplets impacting coolant free surface. A visualization experimental facility of molten fuel coolant interactions (MFCI) is designed and set up in the present study. The lead-bismuth (Pb-Bi) alloys are employed as the metal materials. An automatic control circuit is designed and applied to control the release of the molten droplets. High-speed camera is employed to record the movement of the molten metal droplets falling down and into a coolant pool. Based on the analysis of the experimental data, a so-called ''J-region'' of the droplet's velocity-time curves was found and the melt droplet enters the ''J-region'' when it impacts the free water surface. In the ''J-region'', the velocity of the melt droplet decreases rapidly and suddenly at first, and then increases again. The droplet gradually reaches a comparatively steady velocity when it leaves the ''J-region''. The present study provides essential information for further study on the fragmentation behavior of high-temperature molten droplets in coolant. (author)

Li, Liangxing; Li, Huixiong; Chen, Tingkuan [State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xian, Shaanxi 710049 (China)

2008-02-15

390

Thermal conductivity and viscosity of Al2O3 nanofluid based on car engine coolant  

NASA Astrophysics Data System (ADS)

Various suspensions containing Al2O3 nanoparticles (<50 nm) in a car engine coolant have been prepared using oleic acid as the surfactant and are tested to be stable for more than 80 days. Thermal conductivity and viscosity of the nanofluids have been investigated both as a function of concentration of Al2O3 nanoparticles as well as temperature between 10 and 80 °C. The prepared nanofluid, containing only 0.035 volume fraction of Al2O3 nanoparticles, displays a fairly higher thermal conductivity than the base fluid and a maximum enhancement (knf/kbf) of ~10.41% is observed at room temperature. The thermal conductivity enhancement of the Al2O3 nanofluid based on engine coolant is proportional to the volume fraction of Al2O3. The volume fraction and temperature dependence of the thermal conductivity of the studied nanofluids present excellent correspondence with the model proposed by Prasher et al (2005 Phys. Rev. Lett. 94 025901), which takes into account the role of translational Brownian motion, interparticle potential and convection in fluid arising from Brownian movement of nanoparticles for thermal energy transfer in nanofluids. Viscosity data demonstrate transition from Newtonian characteristics for the base fluid to non-Newtonian behaviour with increasing content of Al2O3 in the base fluid (coolant). The data also show that the viscosity increases with an increase in concentration and decreases with an increase in temperature. An empirical correlation of the type log(?nf) = A exp(-BT) explains the observed temperature dependence of the measured viscosity of Al2O3 nanofluid based on car engine coolant. We further confirm that Al2O3 nanoparticle concentration dependence of the viscosity of nanofluids is very well predicted on the basis of a recently reported theoretical model (Masoumi et al 2009 J. Phys. D: Appl. Phys. 42 055501), which considers Brownian motion of nanoparticles in the nanofluid.

Kole, Madhusree; Dey, T. K.

2010-08-01

391

Prediction of sound radiation from different practical jet engine inlets  

NASA Astrophysics Data System (ADS)

The computer codes necessary for this study were developed and checked against exact solutions generated by the point source method using the NASA Lewis QCSEE inlet geometry. These computer codes were used to predict the acoustic properties of the following five inlet configurations: the NASA Langley Bellmouth, the NASA Lewis JT15D-1 Ground Test Nacelle, and three finite hyperbolic inlets of 50, 70 and 90 degrees. Thirty-five computer runs were done for the NASA Langley Bellmouth. For each of these computer runs, the reflection coefficient at the duct exit plane was calculated as was the far field radiation pattern. These results are presented in both graphical and tabular form with many of the results cross plotted so that trends in the results verses cut-off ratio (wave number) and tangential mode number may be easily identified.

Zinn, B. T.; Meyer, W. L.

1982-07-01

392

Numerical and Test Investigation on an Aircraft Inlet Distortion  

NASA Astrophysics Data System (ADS)

Subscale wind tunnel test of an aircraft vehicle is performed at different Mach number, mass-flow and angle of attack. CFD model, corrected by test results, is also presented to predict inlet performance and total pressure distortion. The result shows total pressure recovery decreases and distortion level rises when Mach number increases from subsonic to supersonic speed, AOA is negative and mass-flow value is too large or too small. Compared linear interpolation based on test result of discrete probes, numerical simulation has advantages in showing inlet flow field predicting actual surface distortion level in AIP plane. Swirl distortion is induced by vortex near the fuselage and adjustable ramp and can strengthen total pressure distortion in AIP at negative AOA. And appropriate suction mass-flow coefficient (1.7% to 3%) is beneficial for inlet performance and total pressure distortion control.

Zhang, Zhang; Hou, Anping; Chen, Yinxiu; Tuo, Wei; Xia, Aiguo

2013-09-01

393

Numerical analysis of flow through scramjet engine inlets  

NASA Technical Reports Server (NTRS)

A set of computer programs was developed to analyze flow through supersonic combustion ramjet (scramjet) inlets. These programs solve either the two or three dimensional Euler/Navier-Stokes equations in full conservation form by MacCormack's explicit or explicit-implicit method. An algebraic two-layer eddy viscosity model is used for turbulent flow calculations. The programs are operational in Control Data CYBER-200 series vector-processing computer system and were optimized to take maximum advantage of the vector processing capability of the system. Since their development, the programs were extensively verified and used to analyze a number of very complex inlet configurations. Results are presented from two-dimensional, quasi-three-dimensional, and three-dimensional analyses of the inlet flow field to illustrate the use of the program.

Kumar, Ajay

1987-01-01

394

Assessment of Thermal and Hydrodynamic Fragmentation in Molten Fuel Coolant Interaction With Simulant System  

SciTech Connect

In the Safety analysis of Fast Breeder Reactor, assessment of Molten Fuel Coolant Interaction (MFCI) assumes importance for two aspects, namely the characterization of the debris and severity of pressure pulses generation. An attempt has been made to investigate the debris generation characteristics with molten Woods Metal (Alloy of Bi 50% Pb 25% Sn 12.5% and Cd 12.5% and melting point of 346 K) - Water simulant system. Liquid Woods metal and liquid Uranium dioxide physical properties (Density, Surface tension and Kinematic viscosity) are similar. Experimental studies were conducted for various melt temperatures covering non - boiling, convective boiling and film boiling regimes of water, to assess the debris generation resulting from both hydrodynamic and thermal interaction. Woods metal was heated to the desired temperature and poured through a hot funnel having a nozzle of 8 mm release diameter into a water column of height up to 140 cm. Experiments were repeated for different coolant temperature and melt inventory up to 5 kg. The melt entry velocity was determined from video recordings. The debris is analyzed on the basis of interface temperature, Rayleigh-Taylor and Kelvin - Helmholtz instabilities. It is observed that Kelvin-Helmholtz instability is the dominant fragmentation phenomena. Contribution due to coolant boiling resulted in more debris generation in the size less than 4 mm. (authors)

Narayanan, K.S.; Das, S.K.; Jasmin Sudha, A.; Rao, E.H.V.M.; Lydia, G.; Murthy, S.S.; Kumareshan, M.; Harvey, J.; Kasinathan, N.; Rajan, M. [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

2006-07-01

395

Surface Water Quality Survey of Northern Indian River Lagoon from Sebastian Inlet to Mosquito Lagoon  

NASA Astrophysics Data System (ADS)

Following news of an emerging brown tide algal bloom in the northern Indian River Lagoon (IRL), researchers sought to gain insight into the surface water quality in the IRL, as well as the extent of the algae coverage. A Portable SeaKeeper from YSI, mounted to a personal watercraft-based coastal profiling system, autonomously collected and analyzed the surface water. The system operates by recording sample data every 12 seconds while continuously underway at speeds up to and greater than 50 km/hr. The researchers covered a transect that started at Sebastian Inlet and followed a zig-zag path extending up through the Haulover Canal and into the Mosquito Lagoon. The survey path covered 166.7 km, and collected 2248 samples. Along the way stops were made at water quality stations used by the Saint John's River Water Management District, so that the data collected can be incorporated into ongoing monitoring efforts. The system analyzed the surface water for dissolved oxygen, pH, chlorophyll-a, salinity, temperature, turbidity, refined fuels, and CDOM. In the two days following the lagoon survey, the inlets at Port Canaveral and Sebastian were also surveyed for tidal currents and hydrography. The IRL transect survey data recorded evidence of the southern extent of the algae bloom in both chlorophyll-a and pH levels. Visual evidence of the bloom was striking as the water in the northern IRL turned a milk chocolaty brown color. Chlorophyll-a levels in the two inlets suggested bloom activity at these locations; however this bloom was different. This oceanic bloom was a result of a persistent upwelling event along the East Florida shelf, and the color was a paler green-yellow. The near-synoptic nature of the comprehensive lagoon survey, conducted in just over 7 hours, allows researchers to obtain a better understanding of water quality in coastal lagoons. Elevated levels of salinity, temperature, and refined fuels in the northern IRL indicate a low exchange rate and absence of flushing. Coordinated studies of circulation through the Haulover Canal, Ponce Inlet and Sebastian Inlet would aid in understanding the genesis of future bloom events.;

Weaver, R. J.; Webb, B. M.

2012-12-01

396

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)

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.

Wilcox, E Clinton; Trout, Arthur M

1951-01-01

397

High pressure coolant effect on PVD coated inserts during end milling of Ti-6AL-4V  

NASA Astrophysics Data System (ADS)

Titanium alloys are being employed extensively in engineering and aerospace applications for their high strength to weight ratio, mechanical strength and ability to withstand high temperatures. Out of the different alloys of titanium available, the most commonly used alloy is Ti-6Al-4V. It is also called `Grade-5 titanium alloy' or '?+? titanium alloy'. High speed machining of titanium alloys generates high temperatures in the cutting zone, promoting accelerated tool wear and reducing the efficiency in metal cutting. Consequently, the ability of the coolant to remove heat from the cutting zone plays an increasingly important role in the economics of the process as well as on the life of tool inserts. With the introduction of thru-tool coolant delivery, the coolant can now be delivered directly at the point of machining without having to flood the area of machining. This research tries to address the effects that high pressure and thru-tool coolant has on insert wear while end milling Ti-6Al-4V. The parameters used in this study are speed, feed, axial depth of cut, radial depth of cut and coolant pressure. A structured design of experiments along with a central composite design approach is used to determine the main effects of coolant pressure and its interactions with the remaining parameters. The results show that, within the parameters of this experiment, coolant pressure was not a significant main effect. However, pressure seems to react positively with feed rate. Contributions from this research can be used to recommend settings of the cutting factors in order to obtain the minimal tool wear.

Sridharan, Arvind

398

Computer programs for calculating potential flow in propulsion system inlets  

NASA Technical Reports Server (NTRS)

In the course of designing inlets, particularly for VTOL and STOL propulsion systems, a calculational procedure utilizing three computer programs evolved. The chief program is the Douglas axisymmetric potential flow program called EOD which calculates the incompressible potential flow about arbitrary axisymmetric bodies. The other two programs, original with Lewis, are called SCIRCL AND COMBYN. Program SCIRCL generates input for EOD from various specified analytic shapes for the inlet components. Program COMBYN takes basic solutions output by EOD and combines them into solutions of interest, and applies a compressibility correction.

Stockman, N. O.; Button, S. L.

1973-01-01

399

Development of a three-dimensional supersonic inlet flow analysis  

NASA Technical Reports Server (NTRS)

A method for computing three dimensional flow in supersonic inlets is described. An approximate set of governing equations is given for viscous flows which have a primary flow direction. The governing equations are written in general orthogonal coordinates. These equations are modified in the subsonic region of the flow to prevent the phenomenon of branching. Results are presented for the two sample cases: a Mach number equals 2.5 flow in a square duct, and a Mach number equals 3.0 flow in a research jet engine inlet. In the latter case the computed results are compared with the experimental data. A users' manual is included.

Buggeln, R. C.; Mcdonald, H.; Levy, R.; Kreskovsky, J. P.

1980-01-01

400

Turbidity-current channels in Queen Inlet, Glacier Bay, Alaska  

USGS Publications Warehouse

Queen Inlet is unique among Glacier Bay fjords because it alone has a branching channel system incised in the Holocene sediment fill of the fjord floor. Queen Inlet and other known channel-containing fjords are marine-outwash fjords; the tidewater glacial fjords do not have steep delta fronts on which slides are generated and may not have a sufficient reservoir of potentially unstable coarse sediment to generate channel-cutting turbidity currents. Presence or absence of channels, as revealed in the ancient rock record, may be one criterion for interpreting types of fjords. -Authors

Carlson, P. R.; Powell, R. D.; Rearic, D. M.

1989-01-01

401

Large perturbation flow field analysis and simulation for supersonic inlets  

NASA Technical Reports Server (NTRS)

An analysis technique for simulation of supersonic mixed compression inlets with large flow field perturbations is presented. The approach is based upon a quasi-one-dimensional inviscid unsteady formulation which includes engineering models of unstart/restart, bleed, bypass, and geometry effects. Numerical solution of the governing time dependent equations of motion is accomplished through a shock capturing finite difference algorithm, of which five separate approaches are evaluated. Comparison with experimental supersonic wind tunnel data is presented to verify the present approach for a wide range of transient inlet flow conditions.

Varner, M. O.; Martindale, W. R.; Phares, W. J.; Kneile, K. R.; Adams, J. C., Jr.

1984-01-01

402

Impact of tidal inlet and its geomorphological changes on lagoon environment: A numerical model study  

NASA Astrophysics Data System (ADS)

Geomorphological changes of a tidal inlet are governed by complex interactions of tidal currents, waves and sediments. Tidal inlet(s) of the Chilika lagoon (19° 28'-19° 54' N; 85° 06'-85° 35' E) on the east coast of India and its geomorphological changes is linked to the contemporary phase of lagoon transformation such as sedimentation (from riverine discharge, land drainage and decay of macrophytes), choking of the outer channel, northward shifting, closing and opening of inlet(s). These transformations are responsible for decrease in salinity, depth and weak lagoon-sea interaction, which in turn are responsible for decline in water area, increase in vegetated area (macrophyte growth) and decrease in fish productivity. The present study investigates the past and present geomorphological changes of Chilika inlet(s) using historical data, satellite data, field observations and numerical modelling techniques. A numerical model was used to simulate the hydrodynamic conditions and salinity distribution in the lagoon for one inlet and multiple inlets and the results are calibrated with observations. The study suggests that tidal inlet(s) and its geomorphological changes have significant impacts on ebb and flood currents at the inlet(s), salinity distribution in the lagoon, sediment and water exchange between the lagoon and sea. Possible impacts of inlet(s) on ecological conditions of the lagoon environment are discussed.

Panda, U. S.; Mohanty, P. K.; Samal, R. N.

2013-01-01

403

A comparison of predicted and measured inlet distortion flows in a subsonic axial inlet flow compressor rotor  

NASA Technical Reports Server (NTRS)

Detailed flow measurements were taken inside an isolated axial compressor rotor operating subsonically near peak efficiency. These Laser Anemometer measurements were made with two inlet velocity profiles. One profile consisted of an unmodified baseline flow, and the second profile was distorted by placing axisymmetric screens on the hub and shroud well upstream of the rotor. A detailed comparison in the rotor relative reference frame between a Navier-Stokes solver and the measured experimental results showed good agreement between the predicted and measured flows. A primary flow is defined in the rotor and deviations and the computed predictions is made to assess the development of a passage vortex due to the distortion of the inlet flow. Computer predictions indicate that a distorted inlet profile has a minimal effect on the development of the flow in the rotor passage and the resulting passage vortex.

Owen, Albert K.

1992-01-01

404

Sloshing of coolant in a seismically isolated reactor  

Microsoft Academic Search

During a seismic event, the liquid coolant inside the reactor vessel will have sloshing motion which is a low-frequency phenomenon. In a reactor system incorporated with seismic isolation, the isolation frequency usually is also very low. There is concern on the potential amplification of sloshing motion of the liquid coolant. This study investigates the effects of seismic isolation on the

Ting-shu Wu; J. Gvildys; R. W. Seidensticker

1988-01-01

405

Method of vacuum degassing and refilling a reactor coolant system  

Microsoft Academic Search

A method is described for vacuum degassing a pressurized water reactor coolant system (RCS) having reactor coolant containing radiogas and nonradiogas and a reactor pressure vessel connected to at least one steam generator by a hot leg, comprising: draining down the RCS to approximately the midpoint of the hot leg; maintaining the RCS in an unvented condition during the step

J. Battaglia; R. W. Fleming

1987-01-01

406

Coolant voiding analysis following SGTR for an HLMC reactor  

Microsoft Academic Search

Concepts are under development at Argonne National Laboratory for a small, modular, proliferation-resistant nuclear power steam supply system. Of primary interest here is the simplified system design, featuring steam generators that are directly immersed in the lead-bismuth eutectic (LBE) coolant of the primary system. To support the safety case for this design approach, model development and analysis of transient coolant

M. T. Farmer; B. W. Spencer; J. J. Sienicki

2000-01-01

407

Recent research and development for the dual-coolant blanket concept in the US  

Microsoft Academic Search

The dual-coolant lead-lithium, or DCLL, blanket concept is of strong interest in the US fusion technology program. In the DCLL blanket, the flow channel insert (FCI) is a critical component. FCIs must have low electrical and thermal conductivity and be compatible with lead–lithium eutectic alloy (Pb–17Li) at elevated temperatures. FCIs must retain structural integrity and desirable properties even under irradiation

Neil B. Morley; Yutai Katoh; Siegfried Malang; Bruce A. Pint; A. R. Raffray; Shahran Sharafat; Sergey Smolentsev; Gerald E. Youngblood

2008-01-01

408

Low cycle fatigue behaviour of TZM molybdenum alloy in divertor water coolant  

Microsoft Academic Search

Load controlled low cycle fatigue (LCF) tests on TZM Mo-alloy have been conducted up to specimen rupture, using two triangular load waveforms of 17 and 20 kN amplitudes, and in high temperature water (250°C), either deaerated or containing separate additions of oxygen (10?5 M\\/l), hydrogen (10?3 M\\/l) and hydrogen peroxide (10?4-10?5 M\\/l), in order to simulate the coolant chemistry inside

Marie-Françoise Maday

1996-01-01

409

Inlet turbulence and fan noise measured in an anechoic wind tunnel and statically with an inlet flow control device  

NASA Technical Reports Server (NTRS)

Turbulence and acoustic measurements were taken in the NASA-Lewis anechoic wind tunnel - a facility which has demonstrated the blade passage tone cutoff phenomena with forward velocity. Turbulence data were taken in a subsonic inlet at various fan speeds under static and forward velocity conditions. A honeycomb/screen flow control device was placed over the inlet during static tests to modify the inflow in an attempt to simulate flight conditions. Acoustic levels of the blade passage tone along with transverse turbulence intensities were reduced with forward velocity. The flow control device reduced the blade passage tone to an intermediate level between those levels associated with static and forward velocity operation.

Shaw, L. M.; Woodward, R. P.; Glaser, F. W.; Dastoli, B. J.

1977-01-01

410

Internal geometry and coolant choices for solid high power neutron spallation targets  

NASA Astrophysics Data System (ADS)

The next generation of neutron spallation sources envisages high power proton beam interaction with a heavy metal target. Solid targets have potentially higher spallation efficiency due to the possibility to use metals with higher density than used in liquid metal targets, but to realize this potential the solid fraction must be high enough. As the power released in the form of heat can reach several MW in the target volume of typically 10 l, target cooling can be a serious challenge. Heat evacuation efficiency for different solid fraction geometries at high power is analyzed for different coolant options (helium, water and gallium) using empirical correlations for friction factors and Nusselt numbers. For estimation of the heat transfer efficiency a parameter ? is introduced characterizing how many watts can be transferred per temperature- and pressure-difference unit. It is demonstrated that water is preferable as a coolant in high convection cases whereas gallium - in medium Peclet number cases when heat conduction in the coolant is important. Strictly focusing on cooling, the results indicate that for a stationary target liquid metals are advantageous in particular conditions. Three options are compared featuring geometries with large internal surfaces and avoiding high pressures. The transition from a stationary target to a rotating one in the case of gallium as coolant improves the heat transfer conditions to a higher degree than for ordinary liquids or gases. An advantage of gallium can be derived from the fact that gallium also acts as a neutron generating medium allowing the target solid fraction to be reduced and a part of the deposited heat is localized in coolant directly.

Buligins, L.; Thomsen, K.; Lielausis, O.; Platacis, E.; Poznaks, A.

2014-10-01

411

Analysis of the SSME HPOTP Bearing Inlet Cavity.  

National Technical Information Service (NTIS)

Analysis of the flow in the Space Shuttle Main Engine (SSME) high pressure oxygen turbopump (HPOTP) bearing no. 1 inlet cavity was completed in support of return-to-flight. With the incorporation of several design changes in the Phase 2 turbopump, rotordy...

P. K. Mcconnaughey

1989-01-01

412

63. Historic detail drawing of inlet duct cone on exhaust ...  

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

63. Historic detail drawing of inlet duct cone on exhaust scrubber at building 202, June 18, 1955. NASA GRC drawing no. CD-101266. (On file at NASA Glenn Research Center). - Rocket Engine Testing Facility, GRC Building No. 202, NASA Glenn Research Center, Cleveland, Cuyahoga County, OH

413

Modular sampling and inlet systems for mobile environmental mass spectrometry  

Microsoft Academic Search

Sampling systems and gas Chromatographic separators based on a modular concept have been developed for a mobile\\/portable quadrupole mass spectrometer. A special quick connector, designed to easily mount and remove the gas Chromatograph from the mass spectrometer, allows the operator to switch between different GC modules within minutes. A polysiloxane inlet membrane seals the vacuum chamber and prevents it from

Gökhan Baykut

1995-01-01

414

46 CFR 42.15-60 - Scuppers, inlets, and discharges.  

Code of Federal Regulations, 2013 CFR

...15-60 Scuppers, inlets, and discharges. (a) Discharges led through the shell either from spaces below the freeboard...doors complying with the requirements of § 42.15-10 shall be led overboard. (e) All valves and shell fittings...

2013-10-01

415

Feasibility Study of Inlet Shock Stability System of YF-12.  

National Technical Information Service (NTIS)

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 ...

G. C. Blausey D. M. Coleman D. S. Harp

1972-01-01

416

Cook Inlet maintaining oil flow in spite of budget reductions  

SciTech Connect

Operators in Alaska's Cook Inlet area are shifting focus from exploration to maintaining production in the face of budget cuts. That follows last year's flurry of exploration that came on the heels of what at first appeared to be a world class discovery, sunfish, in an area that is the cradle of alaska's commercial oil industry. Disappointing follow-up results dampened Cook Inlet exploration excitement, matching industry's recent experience on the North Slope. In Cook Inlet, overall production in the first quarter largely held its own. Seven fields--McArthur River, Middle Ground Shoal, Granite Point, Swanson River, Trading Bay, West McArthur River, and Beaver Creek--produced an average 39,640 b/d, down only 0.2% from last year's 39,700 b/d. That compares with a high of about 72,000 b/d in 1983 but is down only slightly from 41,575 b/d in 1992. Although slowed by budget cuts, Unocal Corp. continues as the major player in the inlet with its Chakachatna project. The project involves development of what Unocal has described as significant bypassed reserves from Platforms Bruce and Anna in the northern portion of Granite Point field and Platforms Baker and Dillon in Middle Ground Shoal field. Trends are discussed.

Not Available

1994-06-20

417

Experimental evaluation of a Mach 3.5 axisymmetric inlet  

NASA Technical Reports Server (NTRS)

Wind tunnel test results for a large scale inlet model designed for Mach 3.5 are presented and compared with analytical predictions. The inlet is an axisymmetric mixed-compression type with a lip diameter of 49.723 cm. The inlet design was developed using analytical procedures. Data are shown for freestream Mach numbers from 0.6 to 3.5. The test results indicate that boundary layer bleed requirements can be accurately predicted. Good agreement was obtained with analytical predictions of the flowfield structure and boundary layer development in the supersonic diffuser yielding high performance at the design Mach number. The highest engine face total pressure recovery at Mach 3.5 was 85.8%; this was obtained at 0.05 Mach tolerance with only 2.8% total pressure distortion and 13.4% bleed. In the started Mach number range from 1.6 to 3.5, the total pressure recovery in the throat, downstream of the terminal normal shock, ranged between 91% and 95%. Total pressure losses in the subsonic diffuser varied from 3% to 13%. The higher losses occuring between Mach 2.5 and 3.2 were believed to be caused by the rapid rate of increase in the area of the diffuser just downstream of the throat, possibly coupled with inadequate centerbody throat bleed. In the unstarted mode at transonic speeds, the maximum inlet flow was over 99% of the theoretical maximum capture mass-flow.

Syberg, J.; Koncsek, J. L.

1975-01-01

418

Inlet and Propulsion Integration of Scram Propelled Vehicles  

NASA Technical Reports Server (NTRS)

The material to be presented in these two lectures begins with cycle considerations of the turbojet engine combined with a ramjet engine to provide thrust over the range of Mach 0 to 5. We will then examine in some detail the aerodynamic behavior that occurs in the inlet operating near the peak speed. Following that, we shall view a numerical simulation through a baseline scramjet engine, starting at the entrance to the inlet, proceeding into the combustor and through the nozzle. In the next segment, we examine a combined rocket and ramjet propulsion system. Analysis and test results will be examined with a view toward evaluation of the concept as a practical device. Two other inlets will then be reviewed: a Mach 12 inlet and a Mach 18 configuration. Finally, we close our lectures with a discussion of the Detonation Wave engine, and inspect the physical and chemical behavior obtained from numerical simulation. A few final remarks will be made regarding the application of CFD for hypersonic propulsion components.

Povinelli, Louis A.

1996-01-01

419

Hypersonic Magneto-Fluid-Dynamic Compression in Cylindrical Inlet  

NASA Technical Reports Server (NTRS)

Hypersonic magneto-fluid-dynamic interaction has been successfully performed as a virtual leading-edge strake and a virtual cowl of a cylindrical inlet. In a side-by-side experimental and computational study, the magnitude of the induced compression was found to be depended on configuration and electrode placement. To better understand the interacting phenomenon the present investigation is focused on a direct current discharge at the leading edge of a cylindrical inlet for which validating experimental data is available. The present computational result is obtained by solving the magneto-fluid-dynamics equations at the low magnetic Reynolds number limit and using a nonequilibrium weakly ionized gas model based on the drift-diffusion theory. The numerical simulation provides a detailed description of the intriguing physics. After validation with experimental measurements, the computed results further quantify the effectiveness of a magnet-fluid-dynamic compression for a hypersonic cylindrical inlet. At a minuscule power input to a direct current surface discharge of 8.14 watts per square centimeter of electrode area produces an additional compression of 6.7 percent for a constant cross-section cylindrical inlet.

Shang, Joseph S.; Chang, Chau-Lyan

2007-01-01

420

RECENT DEVELOPMENTS IN THE GEOMORPHIC INVESTIGATION OF ENGINEERED TIDAL INLETS  

Microsoft Academic Search

In recent years, numerous technological advances have made field studies and laboratory analyses of tidal inlets more time efficient while also substantially improved data qual- ity. Mapping channel bathymetry was once a labor-intensive task that was accomplished by measuring water depths along a detailed network of channel profiles. Now aircraft- operated Light Detection and Ranging (LIDAR) can accurately map the

DUNCAN M. FITZGERALD; GARY A. ZARILLO

421

Low inlet gas velocity high throughput biomass gasifier  

DOEpatents

The present invention discloses a novel method of operating a gasifier for production of fuel gas from carbonaceous fuels. The process disclosed enables operating in an entrained mode using inlet gas velocities of less than 7 feet per second, feedstock throughputs exceeding 4000 lbs/ft.sup.2 -hr, and pressures below 100 psia.

Feldmann, Herman F. (Worthington, OH); Paisley, Mark A. (Upper Arlington, OH)

1989-01-01

422

Baseline data on the oceanography of Cook Inlet, Alaska  

NASA Technical Reports Server (NTRS)

Regional relationships between river hydrology, sediment transport, circulation and coastal processes were analyzed utilizing aircraft, ERTS-1 and N.O.A.A. -2 and -3 imagery and corroborative ground truth data. The use of satellite and aircraft imagery provides a means of acquiring synoptic information for analyzing the dynamic processes of Cook Inlet in a fashion not previously possible.

Gatto, L. W.

1975-01-01

423

Inlet free-stream turbulence effects on diffuser performance  

NASA Technical Reports Server (NTRS)

The performance of a subsonic two dimensional diffuser was experimentally evaluated as a function of inlet free-stream turbulence parameters. Anisotropic inlet free-stream turbulence with the eddy axis perpendicular to the flow and parallel to the diverging walls of the diffuser appears to be more effective at transmitting energy to the diverging walls of the diffuser, thereby improving diffuser performance, as compared to isotropic turbulence or anisotropic turbulence with the eddy axis perpendicular to the diverging walls of the diffuser. The pressure recovery of the diffuser was found to be strongly dependent upon the inlet free-stream total turbulence intensity, was independent of eddy size for large eddy dimensions, and was dependent upon eddy size for small eddy dimensions. The improvement in the diffuser's static pressure recovery coefficient at a total included divergence angle of 20 deg, compared to the low inlet turbulence case, was found to be as much as 21 times larger than the pressure loss across the turbulence generators.

Hoffman, J. A.; Gonzales, G.

1983-01-01

424

Investigation of Inlet Concepts for Maneuver Improvement at Transonic Speeds  

NASA Technical Reports Server (NTRS)

A 15 percent scale lightweight fighter type inlet forebody was tested in the Ames 14 foot transonic wind tunnel at Mach numbers of 0.7, 0.9, and 1.04. The inlet was a two dimensional horizontal ramp system designed for a Mach number of 2.2. Four inlet devices designed to prevent or delay cowl-lip boundary layer separation or to improve the inlet internal flow characteristics at high angles of attack were investigated. The devices used to control cowl-lip separation consisted of cowl leading edge flaps, slotted flaps, and tangential blowing. To improve the internal flow characteristics, discrete jet nozzle flows were directed downstream and parallel to the duct surface in the subsonic diffuser to energize the wall boundary layer. The discrete jets used in the subsonic diffuser were also tested in combination with each of the cowl leading edge devices. Test measurements included engine-face total pressure recovery, steady state distortion, dynamic distortion, duct boundary layer profiles, and duct-surface static pressures.

Latham, E.; Gawienowski, J.; Meriwether, F.

1977-01-01

425

Micro-Ramps for External Compression Low-Boom Inlets  

NASA Technical Reports Server (NTRS)

The application of vortex generators for flow control in an external compression, axisymmetric, low-boom concept inlet was investigated using RANS simulations with three-dimensional (3-D), structured, chimera (overset) grids and the WIND-US code. The low-boom inlet design is based on previous scale model 1- by 1-ft wind tunnel tests and features a zero-angle cowl and relaxed isentropic compression centerbody spike, resulting in defocused oblique shocks and a weak terminating normal shock. Validation of the methodology was first performed for micro-ramps in supersonic flow on a flat plate with and without oblique shocks. For the inlet configuration, simulations with several types of vortex generators were conducted for positions both upstream and downstream of the terminating normal shock. The performance parameters included incompressible axisymmetric shape factor, separation area, inlet pressure recovery, and massflow ratio. The design of experiments (DOE) methodology was used to select device size and location, analyze the resulting data, and determine the optimal choice of device geometry. The optimum upstream configuration was found to substantially reduce the post-shock separation area but did not significantly impact recovery at the aerodynamic interface plane (AIP). Downstream device placement allowed for fuller boundary layer velocity profiles and reduced distortion. This resulted in an improved pressure recovery and massflow ratio at the AIP compared to the baseline solid-wall configuration.

Rybalko, Michael; Loth, Eric; Chima, Rodrick V.; Hirt, Stefanie M.; DeBonis, James R.

2010-01-01

426

Cross contamination in dual inlet isotope ratio mass spectrometers  

Microsoft Academic Search

Since the early days of geochemical isotope ratio mass spectrometry there has always been the problem of cross contamination, i.e. the contamination of the sample gas with traces of reference gas (and vice versa) in a dual inlet system and the analyzer itself. This was attributable to valve leakages and could be corrected for. In modern leak-free machines this problem

H. A. J. Meijer; R. E. M. Neubert; G. H. Visser

2000-01-01

427

Reactor Coolant Pump seal issues and their applicability to new reactor designs.  

National Technical Information Service (NTIS)

Reactor Coolant Pumps (RCPs) of various types are used to circulate the primary coolant through the reactor in most reactor designs. RCPs generally contain mechanical seals to limit the leakage of pressurized reactor coolant along the pump drive shaft int...

C. J. Ruger J. C. Higgins

1993-01-01

428

Long term net exchange of sand through Venice inlets  

NASA Astrophysics Data System (ADS)

Venice lagoon has undergone through the centuries significant morphological changes due to several natural events as well as antropic actions: the diversions of rivers discharging into the lagoon, the construction of long jetties bounding the inlets, sea level rise and subsidence. As a result, the lagoon has progressively deepened and it is claimed nowadays that a loss of roughly one million cubic meters of sediments is experienced by the lagoon each year! Relatively sophisticated models of the inlet hydrodynamics and morphodynamics may be used in order to estimate the net exchange of sediments between lagoon and sea, however they are still computationally demanding to allow for "long term" predictions. In the present work, we formulate a simple model of the inlet hydrodynamics which allows us to estimate the net exchange of sediments associated with the sequence of tidal events recorded for several years. The exercise proves instructive. Firstly, it turns out that the present configuration of each of the inlets is far from the static-equilibrium limit, defined as the condition such that the maximum speed is equal to the critical speed for sediment motion. Secondly, we obtain an estimate of an upper bound for the loss of sediments experienced by each inlet through the years assuming that the amount of sediments carried by both flood and ebb currents is determined by their transport capacity: results suggest that the yearly loss of sand experienced by Venice Lagoon is an order of magnitude smaller than usually claimed. Thirdly, we formulate a simple framework to account for the effect of the sediment overload induced by resuspension due to breaking waves during storm events in the far field: assuming the flood current to be modelled as plane and irrotational, we are able to determine the flow pattern driven by the tidal oscillations and littoral currents in a neighbourhood of the lagoon inlets. Having determined the flow field, the convection-diffusion equation for sediment concentration has been solved numerically and allows us to explain the tendency to inlet siltation associated with sediment resuspension during storm events. Finally, the implications of the above results for the interpretation of the recent morphodynamic evolution of Venice lagoon are discussed.

Tambroni, N.; Seminara, G.

2004-12-01

429

Aerodynamic characteristics of a series of twin-inlet air-breathing missile configurations. 3: Axisymmetric and two-dimensional inlets at subsonic-transonic speeds  

NASA Technical Reports Server (NTRS)

A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configurated 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 fairing or on the inlet fairing 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 twin axisymmetric two dimensional inlet types without internal flow are covered, and the boost configuration of an air-breathing missile is simulated.

Hayes, C.

1983-01-01

430

Coarse mode aerosol measurement using a Low Turbulence Inlet  

NASA Astrophysics Data System (ADS)

The Sahara desert is a major natural source of global mineral dust emissions (Forster et al., 2007) through the mobilisation and lifting of dust particles into the atmosphere from dust storms. A significant fraction of this dust is in the aerosol coarse mode (Weinzierl et al., 2009). It is highlighted of the difficulty in making accurate and reliable measurements from an aircraft platform, particularly that of coarse mode aerosol (Wendisch et al., 2004). To achieve the measurement of a representative aerosol sample an aerosol inlet, on an aircraft, is required for the delivery of the sample to the instruments making the measurements. Inlet design can modify aerosol size distribution through either underestimating due to aerosol losses or overestimation due to enhancements. The Low Turbulence Inlet (LTI) was designed to improve inlet efficiency. This is achieved by reducing turbulence flow within the tip of the inlet, reducing impaction of particles to the walls of the inlet (Wilson et al., 2004). The LTI further maintains isokinetic sampling flow (free stream velocity, U0 and sampling velocity, U are equal to 1). Dust aerosol over the Sahara desert provides an excellent environment to test and quantify the capabilities of the LTI on the FAAM BAe 146, whilst enabling in-situ dust measurement. The LTI was operated during the Fennec field campaign in June 2011 with 11 flights during the campaign over Mauritania and Mali. We are using the LTI to provide critical information on the sampling characteristics of the inlet used by nearly all aerosol instruments inside the aircraft (AMS, Nephelometer, PSAP, and CCN). Inlet experiments were performed with identical Optical Particle Counters (OPC) connected to the rosemount and LTI with size distribution for each inlet measured and Rosemount enhancements determined. Rosemount inlet enhancements were determined to be 2 to 4 times for particles up to 2.5 µm. A key parameter in aerosol measurement is size distribution, in which the LTI is a critical method of sampling quantifiably coarse mode aerosol up to 12 µm into the FAAM BAe 146 aircraft. Size distributions for the Fennec field campaign will be presented. Size distributions from the LTI are found to compare well with that of the externally mounted aircraft probes. A Compact Cascade Impactor (CCI) was incorporated along the sample line and used to collect size segregated particle samples on polyurethane foam (PUF) substrates. X-Ray Diffraction (XRD) analysis is to be used to determine mineralogy of the dust samples. From known dust mineralogy it will be possible to infer the particles optical properties, specifically refractive index. This work was supported by the Natural Environment Research Council and the Met Office. Acknowledgements include Dr J. Wilson, University of Denver, Fennec, FAAM, DLR and Avalon. Forster et al., 2007; Intergovernmental Panel on Climate Change, Cambridge University Press. Weinzierl et al. 2006; Tellus B 61, 96-117. Wendisch et al. 2004; Bulletin of the American Meteorological Society 85, 89-91. Wilson et al. 2004; Aerosol Science and Technology 38, 790-802.

Brooke, J.; Bart, M.; Trembath, J.; McQuaid, J. B.; Brooks, B. J.; Osborne, S.

2012-04-01

431

Quasi 1D Modeling of Mixed Compression Supersonic Inlets  

NASA Technical Reports Server (NTRS)

The AeroServoElasticity task under the NASA Supersonics Project is developing dynamic models of the propulsion system and the vehicle in order to conduct research for integrated vehicle dynamic performance. As part of this effort, a nonlinear quasi 1-dimensional model of the 2-dimensional bifurcated mixed compression supersonic inlet is being developed. The model utilizes computational fluid dynamics for both the supersonic and subsonic diffusers. The oblique shocks are modeled utilizing compressible flow equations. This model also implements variable geometry required to control the normal shock position. The model is flexible and can also be utilized to simulate other mixed compression supersonic inlet designs. The model was validated both in time and in the frequency domain against the legacy LArge Perturbation INlet code, which has been previously verified using test data. This legacy code written in FORTRAN is quite extensive and complex in terms of the amount of software and number of subroutines. Further, the legacy code is not suitable for closed loop feedback controls design, and the simulation environment is not amenable to systems integration. Therefore, a solution is to develop an innovative, more simplified, mixed compression inlet model with the same steady state and dynamic performance as the legacy code that also can be used for controls design. The new nonlinear dynamic model is implemented in MATLAB Simulink. This environment allows easier development of linear models for controls design for shock positioning. The new model is also well suited for integration with a propulsion system model to study inlet/propulsion system performance, and integration with an aero-servo-elastic system model to study integrated vehicle ride quality, vehicle stability, and efficiency.

Kopasakis, George; Connolly, Joseph W.; Paxson, Daniel E.; Woolwine, Kyle J.

2012-01-01

432

Correlations between the electrochemical behaviour and surface film composition of TZM alloy exposed to divertor water coolant environments  

Microsoft Academic Search

X-ray photoelectron spectroscopy (XPS) has been carried out on TZM alloy surfaces after short and long immersion tests in high temperature (250°C) aqueous environments simulating possible fusion reactor coolant conditions during operation. Phase identification by XPS was used in connection with the open circuit potential trends to suggest plausible hypotheses about TZM corrosion behaviour in the various chemical environments considered

Marie-Françoise Maday; Rossella Giorgi; Theodoros Dikonimos-Makris

1997-01-01

433

Temperature  

NSDL National Science Digital Library

Thermometers record the temperature in a given location. Temperature is a non-living thing because it doesn't physically move or eat, for example. However, temperature is a very important factor that effects where animals live and how long they stay in that particular spot.

Luis Miguel Orta Rial (None;)

2008-03-24

434

Augustine Volcano, Cook Inlet, Alaska (January 31, 2006)  

NASA Technical Reports Server (NTRS)

Since last spring, the U.S. Geological Survey's Alaska Volcano Observatory (AVO) has detected increasing volcanic unrest at Augustine Volcano in Cook Inlet, Alaska near Anchorage. Based on all available monitoring data, AVO regards that an eruption similar to 1976 and 1986 is the most probable outcome. During January, activity has been episodic, and characterized by emission of steam and ash plumes, rising to altitudes in excess of 9,000 m (30,000 ft), and posing hazards to aircraft in the vicinity. In the last week, volcanic flows have been seen on the volcano's flanks. An ASTER thermal image was acquired at night at 22:50 AST on January 31, 2006, during an eruptive phase of Augustine. The image shows three volcanic flows down the north flank of Augustine as white (hot) areas. The eruption plume spreads out to the east in a cone shape: it appears dark blue over the summit because it is cold and water ice dominates the composition; further downwind a change to orange color indicates that the plume is thinning and the signal is dominated by the presence of ash.

ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Size: 54 by 51.9 km (33.5 by 32.1 miles) Location: 59.3 deg. North latitude, 153.4 deg. West longitude Orientation: north to top Resolution: 90 m ASTER Date Acquired: January 31, 2006

2006-01-01

435

ISS Internal Active Thermal Control System (IATCS) Coolant Remediation Project  

NASA Technical Reports Server (NTRS)

The IATCS coolant has experienced a number of anomalies in the time since the US Lab was first activated on Flight 5A in February 2001. These have included: 1) a decrease in coolant pH, 2) increases in inorganic carbon, 3) a reduction in phosphate buffer concentration, 4) an increase in dissolved nickel and precipitation of nickel salts, and 5) increases in microbial concentration. These anomalies represent some risk to the system, have been implicated in some hardware failures and are suspect in others. The ISS program has conducted extensive investigations of the causes and effects of these anomalies and has developed a comprehensive program to remediate the coolant chemistry of the on-orbit system as well as provide a robust and compatible coolant solution for the hardware yet to be delivered. The remediation steps include changes in the coolant chemistry specification, development of a suite of new antimicrobial additives, and development of devices for the removal of nickel and phosphate ions from the coolant. This paper presents an overview of the anomalies, their known and suspected system effects, their causes, and the actions being taken to remediate the coolant.

Morrison, Russell H.; Holt, Mike

2005-01-01

436

Experimental Investigation On The Thermal Conductivity And Viscosity Of Engine Coolant Based Alumina Nanofluids  

NASA Astrophysics Data System (ADS)

In the present study, the alumina (Al2O3) nanoparticles (0.1-1.5 v%) with nominal diameter <50 nm are stably dispersed in the HP ``Kool Gard'' car engine Coolant. Thermal conductivity (knf) and viscosity (?nf) of the nanofluids are studied between 5 and 50C. Thermal conductivity of the nanofluid containing 1.5 vol. % Al2O3 shows an enhancement of ~4.2% at 30C, which increases to ~4.5% at 50C. The observed enhancement of knf is in excellent agreement with the model proposed by Prasher et al. Viscosity data reveals that the base fluid (coolant) is a Newtonian fluid at all temperatures, but displays non-Newtonian behavior with increase in particle volume fraction. All classical models under estimate the observed ?nf of the nanofluids. However, the model proposed recently by Masoumi et al., which is derived considering the Brownian motion of the nanoparticles, predicts the measured viscosity very well. An empirical correlation of the type log(?nf) = A exp(BT) explains the temperature dependence of the viscosity of engine coolant based Al2O3 nanofluid.

Kole, Madhusree; Dey, T. K.

2010-06-01

437

Design of the coolant system for the Large Coil Test Facility pulse coils  

SciTech Connect

The pulse coils will be a part of the Large Coil Test Facility in Oak Ridge, Tennessee, which is designed to test six large tokamak-type superconducting coils. The pulse coil set consists of two resistive coaxial solenoid coils, mounted so that their magnetic axis is perpendicular to the toroidal field lines of the test coil. The pulse coils provide transient vertical fields at test coil locations to simulate the pulsed vertical fields present in tokamak devices. The pulse coils are designed to be pulsed for 30 s every 150 s, which results in a Joule heating of 116 kW per coil. In order to provide this capability, the pulse coil coolant system is required to deliver 6.3 L/s (100 gpm) of subcooled liquid nitrogen at 10-atm absolute pressure. The coolant system can also cool down each pulse coil from room temperature to liquid nitrogen temperature. This paper provides details of the pumping and heat exchange equipment designed for the coolant system and of the associated instrumentation and controls.

Bridgman, C.; Ryan, T.L.

1983-01-01

438

High-temperature turbine technology program hot-gas path development test. Part II. Testing  

SciTech Connect

This topical report of the US Department of Energy High-Temperature Turbine Technology (DOE-HTTT) Phase II program presents the results of testing full-scale water-cooled first-stage and second-stage turbine nozzles at design temperature and pressure to verify that the designs are adequate for operation in a full-scale turbine environment. Low-cycle fatigue life of the nozzles was demonstrated by subjecting cascade assemblies to several hundred simulated startup/shutdown turbine cycles. This testing was accomplished in the Hot-Gas Path Development Test Stand (HGPDTS), which is capable of evaluating full-scale combustion and turbine nozzle components. A three-throat cascade of the first-stage turbine nozzle was successfully tested at a nozzle inlet gas temperature of 2630/sup 0/F and a nozzle inlet pressure of 11.3 atmospheres. In addition to steady-state operation at the design firing temperature, the nozzle cascade was exposed to a simulated startup/shutdown turbine cycle by varying the firing temperature. A total of 42 h at the design point and 617 thermal cycles were accumulated during the test periods. First-stage nozzle test results show that measured metal and coolant temperatures correspond well to the predicted design values. This nozzle design has been shown to be fully satisfactory for the application (2600/sup 0/F), with growth capability to 3000/sup 0/F firing temperature. A post-test metallurgical examination of sectioned portions of the tested nozzles shows a totally bonded structure, confirming the test results and attesting to the successful performance of water-cooled composite nozzle hardware.

Horner, M.W.

1982-03-01

439

Circulation on the Ebb Shoal at New River Inlet, NC  

NASA Astrophysics Data System (ADS)

The effects of waves, winds, and tides on the spatially variable circulation (Fig. 1) on an ebb shoal offshore of New River Inlet, NC will be examined with observations collected in April and May 2012. Measurements of currents, waves, tides, and sea levels were obtained at 32 locations in the inlet and ebb shoal channels (2- to 10-m water depths) and across and offshore of the ebb shoal (1- to 5-m water depths). Maximum tidal flows in the inlet channel (onshore of the mouth) were +/- 1.5 m/s. In contrast, tidal flows 500 m offshore of the inlet mouth at the end of a channel recently dredged across the ebb shoal were stronger during ebbs (-1.5 m/s) than during floods (+0.5 m/s). Significant wave heights in 9-m water depth ranged from 0.5 to 2.5 m and wind speeds observed near the inlet mouth ranged from 0 to 14 m/s. Preliminary results suggest wave- and wind-forcing had a significant affect on the flows on the ebb shoal, especially during slack tides. The importance of setup gradients, wave-driven radiation stresses, and wind stresses to the circulation will be discussed. Funding was provided by ONR and NSSEFF. We thank David Clark, Danik Forsman, Levi Gorrell, Jeff Hansen, Sean Kilgallin, Christen Rivera, Jenna Walker, Regina Yopak, and Seth Zippel for helping obtain the data, personnel from the Army Corps of Engineers Field Research Facility for providing bathymetric surveys and excellent logistical support, and Jim Thomson for providing wind measurements.Figure 1: One-hour averaged ebb flow vectors (red arrows, scale on bottom right) at a low tide (pressure record shown at the bottom of the figure with a red dot indicating the time period) on May 6, 2012, at 03:00 EDT superposed on a Google Earth image of New River Inlet, NC. Offshore significant wave heights were about 0.5 m and winds were about 2 m/s from the north.

Raubenheimer, B.; Elgar, S.

2012-12-01

440

Corrosion problems with aqueous coolants, final report  

SciTech Connect

The results of a one year program to characterize corrosion of solar collector alloys in aqueous heat-transfer media are summarized. The program involved a literature review and a laboratory investigation of corrosion in uninhibited solutions. It consisted of three separate tasks, as follows: review of the state-of-the-art of solar collector corrosion processes; study of corrosion in multimetallic systems; and determination of interaction between different waters and chemical antifreeze additives. Task 1 involved a comprehensive review of published literature concerning corrosion under solar collector operating conditions. The reivew also incorporated data from related technologies, specifically, from research performed on automotive cooling systems, cooling towers, and heat exchangers. Task 2 consisted of determining the corrosion behavior of candidate alloys of construction for solar collectors in different types of aqueous coolants containing various concentrations of corrosive ionic species. Task 3 involved measuring the degradation rates of glycol-based heat-transfer media, and also evaluating the effects of degradation on the corrosion behavior of metallic collector materials.

Diegle, R B; Beavers, J A; Clifford, J E

1980-04-11

441

On-line measurement of propofol using membrane inlet ion mobility spectrometer.  

PubMed

The concentration of propofol in patient's exhaled air is an indicator of the anesthetic depth. In the present study, a membrane inlet ion mobility spectrometer (MI-IMS) was built for the on-line measurement of propofol. Compared with the direct sample introduction, the membrane inlet could eliminate the interference of moisture and improve the selectivity of propofol. Effects of membrane temperature and carrier gas flow rate on the sensitivity and response time have been investigated experimentally and theoretically. Under the optimized experimental conditions of membrane temperature 100 °C and carrier gas flow rate 200 mL min(-1), the calculated limit of detection (LOD) for propofol was 1 ppbv, and the calibration curve was linear in the range of 10-83 ppbv with a correlation coefficient (R(2)) of 0.993. Finally, the propofol concentration in an anaesthetized mouse exhaled air was monitored continuously to demonstrate the capability of MI-IMS in the on-line measurement of propofol in real samples. PMID:22939154

Zho