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1

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

Microsoft Academic Search

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 increased to keep about the same ® T across the reactor core. Thermal hydraulic analyses of the current MHR design were performed with these updated

SM Mohsin Reza; Edwin A Harvego; Matt Richards; Arkal Shenoy; Kenneth Lee Peddicord

2

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

SciTech Connect

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 increased to keep about the same _T across the reactor core. Thermal hydraulic analyses of the current MHR design were performed with these updated temperatures to determine the impact of these highter temperatures on pressure drops, coolant flow rates and temperature profiles within the vessel and core regions. Due to these increased operating temperatures, the overall efficiency of hydrogen production processes increases but the steady state reactor vessel temperature is found to be well above the ASME code limits for current vessel materials. Using the RELAP5-3D/ATHENA computer code, an alternative configuration for the MHR coolant inlet flow path was evaluated in an attempt to reduce the reactor vessel temperatures. The coolant inlet flow was shifted from channel boxes located in the annular region between the reactor core barrel and the inner wall of the reactor vessel to a flow path through the outer permanent reflector. Considering the available thickness of graphite in the permanent outer reflector, the total flow area, the number of coolant holes and the coolant-hole diameter were varied to optimize the pressure drop, the coolant inlet velocity and the percentage of graphite removed from the core. The resulting thermal hydraulic analyses of the optimized design showed that peak vessel and fuel temperatures were within acceptable limits for both steady-state and transient operating conditions.

SM Mohsin Reza; E. A. Harvego; Matt Richards; Arkal Shenoy; Kenneth Lee Peddicord

2006-06-01

3

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

4

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

5

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

6

Cooled-turbine aerodynamic performance prediction from reduced primary to coolant total-temperature-ratio results  

NASA Technical Reports Server (NTRS)

The prediction of the cooled aerodynamic performance, for both stators and turbines, at actual primary to coolant inlet total temperature ratios from the results obtained at a reduced total temperature ratio is described. Theoretical and available experimental results were compared for convection film and transpiration cooled stator vanes and for a film cooled, single stage core turbine. For these tests the total temperature ratio varied from near 1.0 to about 2.7. The agreement between the theoretical and the experimental results was, in general, reasonable.

Goldman, L. J.

1976-01-01

7

Stagnation region gas film cooling: Effects of dimensionless coolant temperature  

NASA Technical Reports Server (NTRS)

An experimental investigation was conducted to mode the film cooling performance for a turbine vane leading edge using the stagnation region of a cylinder in cross flow. Experiments were conducted with a single row of spanwise angled (25 deg) coolant holes for a range of the coolant blowing ratio and dimensionless coolant temperature with free stream-to-wall temperature ratio approximately 1.7 and Re sub D = 90000. the cylindrical test surface was instrumented with miniature heat flux gages and wall thermocouples to determine the percentage reduction in the Stanton number as a function of the distance downstream from injection (x/d sub 0) and the location between adjacent holes (z/S). Data from local heat flux measurements are presented for injection from a single row located at 5 deg, 22.9 deg, 40.8 deg, from stagnation using a hole spacing ratio of S/d = 5. The film coolant was injected with T sub c T sub w with a dimensionless coolant temperature in the range 1.18 or equal to theta sub c or equal to 1.56. The data for local Stanton Number Reduction (SNR) showed a significant increase in SNR as theta sub c was increased above 1.0.

Bonnice, M. A.; Lecuyer, M. R.

1983-01-01

8

Effect of pressure ratio and inlet pressure on performance of experimental gas turbine at inlet temperature of 800 R  

NASA Technical Reports Server (NTRS)

An experimental gas turbine was operated over a range of blade-jet speed ratios, total pressure ratios, and inlet total pressures at a constant inlet temperature of 800 R. Peak over-all efficiencies were obtained at blade-jet speed ratios from 0.525 to 0.575 for all runs. The variation in peak efficiency with inlet pressure and pressure ratio was of small magnitude for the conditions investigated.

Kohl, Robert C; Larkin, Robert G

1948-01-01

9

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

10

Design modification for the modular helium reactor for higher temperature operation and reliability studies for nuclear hydrogen production processes  

E-print Network

Design options have been evaluated for the Modular Helium Reactor (MHR) for higher temperature operation. An alternative configuration for the MHR coolant inlet flow path is developed to reduce the peak vessel temperature (PVT). The coolant inlet...

Reza, S.M. Mohsin

2009-05-15

11

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

12

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

13

Comparison of Calculated and Experimental Temperatures and Coolant Pressure Losses for a Cascade of Small Air-Cooled Turbine Rotor Blades  

NASA Technical Reports Server (NTRS)

Average spanwise blade temperatures and cooling-air pressure losses through a small (1.4-in, span, 0.7-in, chord) air-cooled turbine blade were calculated and are compared with experimental nonrotating cascade data. Two methods of calculating the blade spanwise metal temperature distributions are presented. The method which considered the effect of the length-to-diameter ratio of the coolant passage on the blade-to-coolant heat-transfer coefficient and assumed constant coolant properties based on the coolant bulk temperature gave the best agreement with experimental data. The agreement obtained was within 3 percent at the midspan and tip regions of the blade. At the root region of the blade, the agreement was within 3 percent for coolant flows within the turbulent flow regime and within 10 percent for coolant flows in the laminar regime. The calculated and measured cooling-air pressure losses through the blade agreed within 5 percent. Calculated spanwise blade temperatures for assumed turboprop engine operating conditions of 2000 F turbine-inlet gas temperature and flight conditions of 300 knots at a 30,000-foot altitude agreed well with those obtained by the extrapolation of correlated experimental data of a static cascade investigation of these blades.

Stepka, Francis S

1958-01-01

14

Heat transfer experiments simulating a failure of the inlet piping to a BDF reactor process tube  

Microsoft Academic Search

Laboratory heat transfer experiments were conduced to investigate fuel element temperatures which could result from coolant flow loss following a failure of the inlet piping to a process tube at a B, D, F, DR, or H reactor. The results are reported herein. Failure of the inlet coolant piping between the front header and the process tube on a reactor

E. D. Waters; M. R. Kreiter

1961-01-01

15

Effects of temperature transients at fan inlet of a turbofan engine  

NASA Technical Reports Server (NTRS)

The effects of fan inlet temperature transients on the performance and stability of a turbofan engine were determined. The experiment was conducted at 90 and 74 percent of low-pressure-rotor military speed (9525 rpm) and with fan inlet temperature distortions having circumferential extents of 90 deg, 180 deg, 270 deg, and 360 deg. Temperature transients were controlled by varying the magnitude and rate of change of the inlet temperature rise. The engine response ranged from a momentary compressor pressure disturbance to low-pressure-compressor stall. The compressor distortion limits decreased with decreasing low-pressure-rotor speed and increased with increasing circumferential extent of distortion. Analysis of the data suggests strongly that the distortion limits of the compressor are a function of a critical magnitude of inlet temperature rise and are independent of the temperature rise rate.

Abdelwahab, M.

1977-01-01

16

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

NASA Technical Reports Server (NTRS)

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

Cochran, Reeves P.; Dengler, Robert P.

1961-01-01

17

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

18

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

19

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

20

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

DOEpatents

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, Wayne H. (Richland, WA); Christiansen, David W. (Kennewick, WA)

1987-01-01

21

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

NASA Technical Reports Server (NTRS)

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

Gary, Bruce L. (Inventor)

2001-01-01

22

Analysis of a water-coolant leak into a very high-temperature vitrification chamber.  

SciTech Connect

A coolant-leakage incident occurred during non-radioactive operation of the Plasma Hearth Process waste-vitrification development system at Argonne National Laboratory when a stray electric arc ruptured az water-cooling jacket. Rapid evaporation of the coolant that entered the very high-temperature chamber pressurized the normally sub-atmospheric system above ambient pressure for over 13 minutes. Any positive pressurization, and particularly a lengthy one, is a safety concern since this can cause leakage of contaminants from the system. A model of the thermal phenomena that describe coolant/hot-material interactions was developed to better understand the characteristics of this type of incident. The model is described and results for a variety of hypothetical coolant-leak incidents are presented. It is shown that coolant leak rates above a certain threshold will cause coolant to accumulate in the chamber, and evaporation from this pool can maintain positive pressure in the system long after the leak has been stopped. Application of the model resulted in reasonably good agreement with the duration of the pressure measured during the incident. A closed-form analytic solution is shown to be applicable to the initial leak period in which the peak pressures are generated, and is presented and discussed.

Felicione, F. S.

1998-06-11

23

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

24

Load following capability of CANDLE reactor by adjusting coolant operation condition  

SciTech Connect

The load following capability of CANDLE reactor is investigated in the condition that the control rods are unavailable. Both sodium cooled metallic fuel fast reactor (SFR) and {sup 208}Pb cooled metallic fuel fast reactor (LFR) are investigated for their performance in power rate changing by changing its coolant operation condition; either coolant flow rate or coolant inlet temperature. The change by coolant flow rate is difficult especially for SFR because the maximum temperature criteria on cladding material may be violated. The power rate can be changed for its full range easily by changing the coolant temperature at the core inlet. LFR can reduce the same amount of power rate by smaller change of temperature than SFR. However, the coolant output temperature is generally decreased for this method and the thermal efficiency becomes worse.

Sekimoto, Hiroshi; Nakayama, Sinsuke [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology 2-12-1-N1-17, Ookayama, Meguro-ku 152-8550 (Japan)

2012-06-06

25

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

26

Effect of Steady-State Temperature Distortion on Inlet Flow to a High-Bypass-Ratio Turbofan Engine  

NASA Technical Reports Server (NTRS)

The effects of circumferential inlet temperature distortion on the flow characteristics between a distortion generator and a high bypass ratio turbofan engine and through its compression system were evaluated to support the effort to generate analytical models. The flow characteristics are defined by the inlet duct, the flow angles, and the total temperature, total pressure, and static pressure profiles in the inlet duct and through the fan and compressor. The effects of Reynolds number, rotor speed, and distortion extent are also considered.

Soeder, R. H.; Mehalic, C. M.; Stancik, K.

1985-01-01

27

Effect of turbine inlet temperature on rotor blade tip leakage flow and heat transfer  

Microsoft Academic Search

Purpose – One of the most critical gas turbine engine components, the rotor blade tip and casing, is exposed to high thermal load. It becomes a significant design challenge to protect the turbine materials from this severe situation. The purpose of this paper is to study numerically the effect of turbine inlet temperature on the tip leakage flow structure and

Sung In Kim; Ibrahim Hassan

2012-01-01

28

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

SciTech Connect

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 (where applicable), and dc-link capacitors. The new coolant system under study would abandon the dedicated 65 C coolant loop, such as used in the Prius, and instead rely on the 105 C engine cooling loop. This assessment is important because automotive manufacturers are interested in utilizing the existing water/glycol engine cooling loop to cool the HEV subassemblies in order to eliminate an additional coolant loop with its associated reliability, space, and cost requirements. In addition, the cooling of power electronic devices, traction motors, and generators is critical in meeting the U.S. Department of Energy (DOE) FreedomCAR and Vehicle Technology (FCVT) goals for power rating, volume, weight, efficiency, reliability, and cost. All of these have been addressed in this study. Because there is high interest by the original equipment manufacturers (OEMs) in reducing manufacturing cost to enhance their competitive standing, the approach taken in this analysis was designed to be a positive 'can-do' approach that would be most successful in demonstrating the potential or opportunity of relying entirely on a high-temperature coolant system. Nevertheless, it proved to be clearly evident that a few formidable technical and cost barriers exist and no effective approach for mitigating the barriers was evident in the near term. Based on comprehensive thermal tests of the Prius reported by ORNL in 2005 [1], the continuous ratings at base speed (1200 rpm) with different coolant temperatures were projected from test data at 900 rpm. They are approximately 15 kW with 103 C coolant and 20 kW with 50 C coolant. To avoid this 25% drop1 in continuous power, design changes for improved heat dissipation and carefully managed changes in allowable thermal limits would be required in the hybrid subsystems. This study is designed to identify the technical barriers that potentially exist in moving to a high-temperature cooling loop prior to addressing the actual detailed design. For operation at a significantly higher coolant temperature, there were component-level issues that had to be addressed in this study. These issues generally pertained to the cost and reliability of existing or near term components that would be suitable for use with the 105 C coolant. The assessed components include power electronic devices/modules such as diodes and insulated-gate bipolar transistors (IGBTs), inverter-grade high-temperature capacitors, permanent magnets (PM), and motor-grade wire insulation. The need for potentially modifying/resizing subassemblies such as inverters, motors, and heat exchangers was also addressed in the study. In order to obtain pertinent information to assist ORNL researchers address the thermal issues at the component, module, subassembly, and system levels, pre-existing laboratory test data conducted at varying temperatures was analyzed in conjunction with information obtained from technical literature searches and industry sources.

Hsu, J.S.; Staunton, M.R.; Starke, M.R.

2006-09-30

29

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

SciTech Connect

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 (where applicable), and dc-link capacitors. The new coolant system under study would abandon the dedicated 65 C coolant loop, such as used in the Prius, and instead rely on the 105 C engine cooling loop. This assessment is important because automotive manufacturers are interested in utilizing the existing water/glycol engine cooling loop to cool the HEV subassemblies in order to eliminate an additional coolant loop with its associated reliability, space, and cost requirements. In addition, the cooling of power electronic devices, traction motors, and generators is critical in meeting the U.S. Department of Energy (DOE) FreedomCAR and Vehicle Technology (FCVT) goals for power rating, volume, weight, efficiency, reliability, and cost. All of these have been addressed in this study. Because there is high interest by the original equipment manufacturers (OEMs) in reducing manufacturing cost to enhance their competitive standing, the approach taken in this analysis was designed to be a positive 'can-do' approach that would be most successful in demonstrating the potential or opportunity of relying entirely on a high-temperature coolant system. Nevertheless, it proved to be clearly evident that a few formidable technical and cost barriers exist and no effective approach for mitigating the barriers was evident in the near term. Based on comprehensive thermal tests of the Prius reported by ORNL in 2005 [1], the continuous ratings at base speed (1200 rpm) with different coolant temperatures were projected from test data at 900 rpm. They are approximately 15 kW with 103 C coolant and 20 kW with 50 C coolant. To avoid this 25% drop1 in continuous power, design changes for improved heat dissipation and carefully managed changes in allowable thermal limits would be required in the hybrid subsystems. This study is designed to identify the technical barriers that potentially exist in moving to a high-temperature cooling loop prior to addressing the actual detailed design. For operation at a significantly higher coolant temperature, there were component-level issues that had to be addressed in this study. These issues generally pertained to the cost and reliability of existing or near-term components that would be suitable for use with the 105 C coolant. The assessed components include power electronic devices/modules such as diodes and insulated-gate bipolar transistors (IGBTs), inverter-grade high-temperature capacitors, permanent magnets (PM), and motor-grade wire insulation. The need for potentially modifying/resizing subassemblies such as inverters, motors, and heat exchangers was also addressed in the study. In order to obtain pertinent information to assist ORNL researchers address the thermal issues at the component, module, subassembly, and system levels, pre-existing laboratory test data conducted at varying temperatures was analyzed in conjunction with information obtained from technical literature searches and industry sources.

Staunton, Robert H [ORNL; Hsu, John S [ORNL; Starke, Michael R [ORNL

2006-09-01

30

Nuclear reactor coolant pump with internal self-cooling arrangement  

Microsoft Academic Search

This patent describes a nuclear reactor coolant pump for pumping reactor coolant fluid in a reactor coolant system. It comprises a casing having an end defining a central inlet nozzle for receiving a reactor coolant fluid, a peripheral outlet nozzle, for discharging the reactor coolant fluid, and an annular passage interconnecting the inlet nozzle and the outlet nozzle; a central

J. R. Raymond; C. I. Thompson

1992-01-01

31

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

32

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

33

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

34

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

2010-07-01

35

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

2010-07-01

36

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...How do I monitor the temperature of flue gases at the inlet of my particulate matter...How do I monitor the temperature of flue gases at the inlet of my particulate matter...continuously measure the temperature of the flue gas stream at the inlet of each...

2010-07-01

37

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

38

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

39

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

40

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

41

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

42

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

43

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

44

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

45

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

46

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

47

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

48

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

49

New experimental device for VHTR structural material testing and helium coolant chemistry investigation – High Temperature Helium Loop in NRI ?ež  

Microsoft Academic Search

The High Temperature Helium Loop (HTHL) is an experimental device for simulation of VHTR helium coolant conditions. The purpose of the HTHL is structural materials testing and helium coolant chemistry investigation. In the HTHL pure helium will be used as working medium and its main physical parameters are 7MPa, max. temperature in the test section 900°C and flow rate 37.8kg\\/h.

Jan Berka; Josef Mat?cha; Michal ?erný; Ivan Víden; Frantisek Sus; Petr Hájek

50

Corrosion of Ferritic Steels in High Temperature Molten Salt Coolants for Nuclear Applications  

SciTech Connect

Corrosion of ferritic steels in high temperature molten fluoride salts may limit the life of advanced reactors, including some hybrid systems that are now under consideration. In some cases, the steel may be protected through galvanic coupling with other less noble materials with special neutronic properties such a beryllium. This paper reports the development of a model for predicting corrosion rates for various ferritic steels, with and without oxide dispersion strengthening, in FLiBe (Li{sub 2}BeF{sub 4}) and FLiNaK (Li-Na-K-F) coolants at temperatures up to 800 C. Mixed potential theory is used to account for the protection of steel by beryllium, Tafel kinetics are used to predict rates of dissolution as a function of temperature and potential, and the thinning of the mass-transfer boundary layer with increasing Reynolds number is accounted for with dimensionless correlations. The model also accounts for the deceleration of corrosion as the coolants become saturated with dissolved chromium and iron. This paper also reports electrochemical impedance spectroscopy of steels at their corrosion potentials in high-temperature molten salt environments, with the complex impedance spectra interpreted in terms of the interfacial charge transfer resistance and capacitance, as well as the electrolyte conductivity. Such in situ measurement techniques provide valuable insight into the degradation of materials under realistic conditions.

Farmer, J; El-Dasher, B; de Caro, M S; Ferreira, J

2008-11-25

51

Effect of inlet temperature and pressure on emissions from a premixing gas turbine primary zone combustor  

NASA Technical Reports Server (NTRS)

Experiments were conducted to determine the performance of a premixing prevaporizing gas turbine primary zone combustor design over a range of combustor inlet temperatures from 700 to 1000 K and a range of inlet pressures from 40 to 240 N/sq cm. The 1 meter long combustor could be operated at pressures up to and including 120 N/sq cm without autoignition in the premixing duct or flashback from the stabilized combustion zone. Autoignition occurred in the mixer tube at the 240 N/sq cm pressure level with an entrance temperature of 830 K and a mixer residence time of 4 msec. Measured NOx level, combustion inefficiency, and hydrocarbon emission index correlated well with adiabatic flame temperature. The NOx levels varied from approximately 0.2 to 2.0 g NO2/kg fuel at combustion inefficiencies from 4 to 0.04 percent, depending upon adiabatic flame temperature and pressure. Measured NOx levels were sensitive to pressure. Tests were made at equivalence ratios ranging from 0.35 to 0.65. The overall total pressure drop for the configuration varied slightly with reference velocity and equivalence ratio, but never exceeded 3 percent.

Roffe, G.

1976-01-01

52

Current instability mechanisms in high-temperature superconductors cooled by liquid coolant  

Microsoft Academic Search

The instability of the steady current state in high-temperature superconductors (Bi2Sr2CaCu2O8, Bi2Sr2Ca2Cu3O8 and YBa2Cu3O7) cooled by a liquid refrigerant (helium, hydrogen and nitrogen) is studied. It is shown that the mechanism of the current instability depends on the type of coolant. Firstly, the destruction of stable current states may occur after transition of the cooling conditions on the surface of

V R Romanovskii

2010-01-01

53

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

54

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

55

Performance of a high-work low aspect ration turbine tested with a realistic inlet radial temperature profile  

NASA Technical Reports Server (NTRS)

Experimental results are presented for a 0.767 scale model of the first stage of a two-stage turbine designed for a high by-pass ratio engine. The turbine was tested with both uniform inlet conditions and with an inlet radial temperature profile simulating engine conditions. The inlet temperature profile was essentially mixed-out in the rotor. There was also substantial underturning of the exit flow at the mean diameter. Both of these effects were attributed to strong secondary flows in the rotor blading. There were no significant differences in the stage performance with either inlet condition when differences in tip clearance were considered. Performance was very close to design intent in both cases.

Stabe, R. G.; Whitney, W. J.; Moffitt, T. P.

1984-01-01

56

Assessment of Candidate Molten Salt Coolants for the Advanced High Temperature Reactor (AHTR)  

SciTech Connect

The Advanced High-Temperature Reactor (AHTR) is a novel reactor design that utilizes the graphite-matrix high-temperature fuel of helium-cooled reactors, but provides cooling with a high-temperature fluoride salt. For applications at temperatures greater than 900 C the AHTR is also referred to as a Liquid-Salt-Cooled Very High-Temperature Reactor (LS-VHTR). This report provides an assessment of candidate salts proposed as the primary coolant for the AHTR based upon a review of physical properties, nuclear properties, and chemical factors. The physical properties most relevant for coolant service were reviewed. Key chemical factors that influence material compatibility were also analyzed for the purpose of screening salt candidates. Some simple screening factors related to the nuclear properties of salts were also developed. The moderating ratio and neutron-absorption cross-section were compiled for each salt. The short-lived activation products, long-lived transmutation activity, and reactivity coefficients associated with various salt candidates were estimated using a computational model. Table A presents a summary of the properties of the candidate coolant salts. Certain factors in this table, such as melting point, vapor pressure, and nuclear properties, can be viewed as stand-alone parameters for screening candidates. Heat-transfer properties are considered as a group in Sect. 3 in order to evaluate the combined effects of various factors. In the course of this review, it became apparent that the state of the properties database was strong in some areas and weak in others. A qualitative map of the state of the database and predictive capabilities is given in Table B. It is apparent that the property of thermal conductivity has the greatest uncertainty and is the most difficult to measure. The database, with respect to heat capacity, can be improved with modern instruments and modest effort. In general, ''lighter'' (low-Z) salts tend to exhibit better heat transfer and nuclear performance metrics. Lighter salts also tend to have more favorable (larger) moderating ratios, and thus should have a more favorable coolant-voiding behavior in-core. Heavy (high-Z) salts tend to have lower heat capacities and thermal conductivities and more significant activation and transmutation products. However, all of the salts are relatively good heat-transfer agents. A detailed discussion of each property and the combination of properties that served as a heat-transfer metric is presented in the body of this report. In addition to neutronic metrics, such as moderating ratio and neutron absorption, the activation properties of the salts were investigated (Table C). Again, lighter salts tend to have more favorable activation properties compared to salts with high atomic-number constituents. A simple model for estimating the reactivity coefficients associated with a reduction of salt content in the core (voiding or thermal expansion) was also developed, and the primary parameters were investigated. It appears that reasonable design flexibility exists to select a safe combination of fuel-element design and salt coolant for most of the candidate salts. Materials compatibility is an overriding consideration for high-temperature reactors; therefore the question was posed whether any one of the candidate salts was inherently, or significantly, more corrosive than another. This is a very complex subject, and it was not possible to exclude any fluoride salts based on the corrosion database. The corrosion database clearly indicates superior container alloys, but the effect of salt identity is masked by many factors which are likely more important (impurities, redox condition) in the testing evidence than salt identity. Despite this uncertainty, some reasonable preferences can be recommended, and these are indicated in the conclusions. The reasoning to support these conclusions is established in the body of this report.

Williams, D.F.

2006-03-24

57

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

NASA Technical Reports Server (NTRS)

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

Gardiner, Arthur W; Schey, Oscar W

1928-01-01

58

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

59

The effect of feed solids concentration and inlet temperature on the flavor of spray dried whey protein concentrate.  

PubMed

Previous research has demonstrated that unit operations in whey protein manufacture promote off-flavor production in whey protein. The objective of this study was to determine the effects of feed solids concentration in liquid retentate and spray drier inlet temperature on the flavor of dried whey protein concentrate (WPC). Cheddar cheese whey was manufactured, fat-separated, pasteurized, bleached (250 ppm hydrogen peroxide), and ultrafiltered (UF) to obtain WPC80 retentate (25% solids, wt/wt). The liquid retentate was then diluted with deionized water to the following solids concentrations: 25%, 18%, and 10%. Each of the treatments was then spray dried at the following temperatures: 180 °C, 200 °C, and 220 °C. The experiment was replicated 3 times. Flavor of the WPC80 was evaluated by sensory and instrumental analyses. Particle size and surface free fat were also analyzed. Both main effects (solids concentration and inlet temperature) and interactions were investigated. WPC80 spray dried at 10% feed solids concentration had increased surface free fat, increased intensities of overall aroma, cabbage and cardboard flavors and increased concentrations of pentanal, hexanal, heptanal, decanal, (E)2-decenal, DMTS, DMDS, and 2,4-decadienal (P < 0.05) compared to WPC80 spray dried at 25% feed solids. Product spray dried at lower inlet temperature also had increased surface free fat and increased intensity of cardboard flavor and increased concentrations of pentanal, (Z)4-heptenal, nonanal, decanal, 2,4-nonadienal, 2,4-decadienal, and 2- and 3-methyl butanal (P < 0.05) compared to product spray dried at higher inlet temperature. Particle size was higher for powders from increased feed solids concentration and increased inlet temperature (P < 0.05). An increase in feed solids concentration in the liquid retentate and inlet temperature within the parameters evaluated decreased off-flavor intensity in the resulting WPC80. PMID:24329978

Park, Curtis W; Bastian, Eric; Farkas, Brian; Drake, MaryAnne

2014-01-01

60

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

61

Analytical and Experimental Study of Flow Through an Axial Turbine Stage with a Nonuniform Inlet Radial Temperature Profile  

NASA Technical Reports Server (NTRS)

Results are presented for a typical nonuniform inlet radial temperature profile through an advanced single-stage axial turbine and compared with the results obtained for a uniform profile. Gas temperature rises of 40 K to 95 K are predicted at the hub and tip corners at the trailing edges of the pressure surfaces in both the stator and rotor due to convection of hot fluid from the mean by the secondary flow. The inlet temperature profile is shown to be mixed out at the rotor exit survey plane (2.3 axial chords downstream of the rotor trailing edge) in both the analysis and the experiment. The experimental rotor exit angle profile for the nonuniform inlet temperature profile indicates underturning at the tip caused by increased clearance. Severe underturning also occurs at the mean, both with and without the nonuniform inlet temperature profile. The inviscid rotational flow code used in the analysis fails to predict the underturning at the mean, which may be caused by viscous effects.

Schwab, J. R.; Stabe, R. G.; Whitney, W. J.

1983-01-01

62

Analytical and experimental study of flow through an axial turbine stage with a nonuniform inlet radial temperature profile  

NASA Technical Reports Server (NTRS)

Results are presented for a typical nonuniform inlet radial temperature profile through an advanced single-stage axial turbine and compared with the results obtained for a uniform profile. Gas temperature rises of 40 K to 95 K are predicted at the hub and tip corners at the trailing edges of the pressure surfaces in both the stator and rotor due to convection of hot fluid from the mean by the secondary flow. The inlet temperature profile is shown to be mixed out at the rotor exit survey plane (2.3 axial chords downstream of the rotor trailing edge) in both the analysis and the experiment. The experimental rotor exit angle profile for the nonuniform inlet temperature profile indicates underturning at the tip caused by increased clearance. Severe underturning also occurs at the mean, both with and without the nonuniform inlet temperature profile. The inviscid rotational flow code used in the analysis fails to predict the underturning at the mean, which may be caused by viscous effects. Previously announced in STAR as N83-27958

Schwab, J. R.; Stabe, R. G.; Whitney, W. J.

1983-01-01

63

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

64

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

65

Effect of temperature in cutting deep holes on the content of harmful components in oil-based coolants  

Microsoft Academic Search

It was found that in cutting deep holes, with an increase in the temperature from 20 to 80°C, the content of harmful components:\\u000a 9- and 2-methylanthracene, 3-methylphenanthrene, etc., in oil-based MR-3K coolant (CL) decreases by 15–25%, i.e., they enter\\u000a the air of the working zone. The necessity of additional treatment of CL to remove polycyclic aromatic hydrocarbons to minimize\\u000a the

N. V. Skoropistseva; Yu. V. Golubkov; M. E. Kushcheva

2010-01-01

66

Effect of an inlet temperature disturbance on the propagation of methane-air premixed flames in small tubes  

SciTech Connect

A flame stabilized in a tube is affected by the temperature disturbance and velocity profile at the inlet boundary. Thus, a multi-dimensional analysis is necessary near the flame. The deviation between one-dimensional and two-dimensional analyses near the flame was investigated quantitatively. The temperature profile in the radial direction was varied to investigate its effects on the propagation of methane-air premixed flames in small tubes. A numerical experiment with Navier-Stokes equations, an energy equation and species equations was conducted coupled with a single-step global-reaction model. Three different temperature profiles were examined for slip and no-slip wall boundary conditions. The effect of temperature profiles on the flame propagation velocity and flame shapes was not negligible depending on the magnitude of the temperature deviation and the tube diameter. This study evaluated a critical length scale of a computational domain or a thermal entrance length of a premixed flame over which the inlet temperature disturbance does not affect the flame characteristics. (author)

Kim, Nam Il [School of Mechanical Engineering, Chung-Ang University, 221, Heukseok, Dongjak, Seoul 156-756 (Korea)

2009-07-15

67

Transient simulation of coolant peak temperature due to prolonged fan and/or water pump operation after the vehicle is keyed-off  

NASA Astrophysics Data System (ADS)

Automotive designers should design a robust engine cooling system which works well in both normal and severe driving conditions. When vehicles are keyed-off suddenly after some distance of hill-climbing driving, the coolant temperature tends to increase drastically. This is because heat soak in the engine could not be transferred away in a timely manner, as both the water pump and cooling fan stop working after the vehicle is keyed-off. In this research, we aimed to visualize the coolant temperature trend over time before and after the vehicles were keyed-off. In order to prevent coolant temperature from exceeding its boiling point and jeopardizing engine life, a numerical model was further tested with prolonged fan and/or water pump operation after keying-off. One dimensional thermal-fluid simulation was exploited to model the vehicle's cooling system. The behaviour of engine heat, air flow, and coolant flow over time were varied to observe the corresponding transient coolant temperatures. The robustness of this model was proven by validation with industry field test data. The numerical results provided sensible insights into the proposed solution. In short, prolonging fan operation for 500 s and prolonging both fan and water pump operation for 300 s could reduce coolant peak temperature efficiently. The physical implementation plan and benefits yielded from implementation of the electrical fan and electrical water pump are discussed.

Pang, Suh Chyn; Masjuki, Haji Hassan; Kalam, Md. Abul; Hazrat, Md. Ali

2014-01-01

68

The Effect of Inlet Temperature and Pressure on the Efficiency of a 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

69

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

70

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

71

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

72

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

73

Computer program MCAP-TOSS calculates steady-state fluid dynamics of coolant in parallel channels and temperature distribution in surrounding heat-generating solid  

NASA Technical Reports Server (NTRS)

Computer program calculates the steady state fluid distribution, temperature rise, and pressure drop of a coolant, the material temperature distribution of a heat generating solid, and the heat flux distributions at the fluid-solid interfaces. It performs the necessary iterations automatically within the computer, in one machine run.

Lee, A. Y.

1967-01-01

74

Metal temperatures and coolant flow in a wire cloth transpiration cooled turbine vane  

NASA Technical Reports Server (NTRS)

An experimental heat transfer investigation was conducted on an air-cooled turbine vane made from wire-wound cloth material and supported by a central strut. Vane temperature data obtained are compared with temperature data from two full-coverage film-cooled vanes made of different laminated construction. Measured porous-airfoil temperatures are compared with predicted temperatures.

Gladden, H. J.

1975-01-01

75

Bypass valve and coolant flow controls for optimum temperatures in waste heat recovery systems  

DOEpatents

Implementing an optimized waste heat recovery system includes calculating a temperature and a rate of change in temperature of a heat exchanger of a waste heat recovery system, and predicting a temperature and a rate of change in temperature of a material flowing through a channel of the waste heat recovery system. Upon determining the rate of change in the temperature of the material is predicted to be higher than the rate of change in the temperature of the heat exchanger, the optimized waste heat recovery system calculates a valve position and timing for the channel that is configurable for achieving a rate of material flow that is determined to produce and maintain a defined threshold temperature of the heat exchanger, and actuates the valve according to the calculated valve position and calculated timing.

Meisner, Gregory P

2013-10-08

76

Sizing of focused solar collector fields with specified collector tube inlet temperature  

Microsoft Academic Search

An axial temperature differential analysis was used to size the collector field required to power a demonstration project in which 40 kW (electrical) output is required. The number of collectors required to furnish the desired energy and temperature rise in the collector fluid is determined by the requirements of several typical organic working fluid Rankine-cycle energy conversion systems. Calculations based

D. O. Lee; W. P. Schimmel Jr.; J. P. Abbin Jr.

1974-01-01

77

Attic inlet technology  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

78

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

79

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

NASA Astrophysics Data System (ADS)

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

Kumar, S.; Singh, O.

2012-10-01

80

Hepatic radiofrequency ablation with internally cooled probes: effect of coolant temperature on lesion size  

Microsoft Academic Search

Radiofrequency (RF) ablation is a minimally invasive method for treatment of primary and metastatic liver tumors. One of the currently commercially available devices employs an internally cooled 17-gauge needle probe. Within the probe, cool water is circulated during ablation, which cools tissue close to the probe resulting in larger lesions. We evaluated the effect of different cooling water temperatures on

Dieter Haemmerich; Louay Chachati; Andrew S. Wright; David M. Mahvi; J. G. Webster

2003-01-01

81

Muir Inlet  

USGS Multimedia Gallery

This ship-deck-based photograph of Muir Glacier and Muir Inlet, Glacier Bay National Park and Preserve, St. Elias Mountains, Alaska, is taken towards the north-northwest and shows the nearly 50-m-high retreating tidewater terminus of the glacier with part of its face capped by a few angular sé...

82

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

83

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

NASA Technical Reports Server (NTRS)

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

Tower, Leonard K; Gammon, Benson E

1953-01-01

84

Amplification of inlet temperature disturbances in a packed-bed reactor for CO oxidation over Pt\\/Al 2O 3  

Microsoft Academic Search

The commonly used packed-bed catalytic reactor can exhibit complex dynamic features such as wrong-way behavior, differential-flow instability, different kinds of traveling waves and bifurcation behavior. Understanding these phenomena is essential for developing reliable reactor control systems. Of primary interest to the present study is the differential flow instability, which may cause amplification of small amplitude inlet perturbations of concentration, temperature,

A. Jaree; R. R. Hudgins; H. Budman; P. L. Silveston; V. Yakhnin; M. Menzinger

2003-01-01

85

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

86

Turbomachine injection nozzle including a coolant delivery system  

SciTech Connect

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

87

Coolant pressure and airflow distribution in a strut-supported transpiration-cooled vane for a gas turbine engine  

NASA Technical Reports Server (NTRS)

An analysis to predict pressure and flow distribution in a strut-supported wire-cloth vane was developed. Results were compared with experimental data obtained from room-temperature airflow tests conducted over a range of vane inlet airflow rates from 10.7 to 40.4 g/sec (0.0235 to 0.0890 lb/sec). The analytical method yielded reasonably accurate predictions of vane coolant flow rate and pressure distribution.

Kaufman, A.; Poferl, D. J.; Richards, H. T.

1972-01-01

88

Study of coolant activation and dose rates with flow rate and power perturbations in pool-type research reactors  

SciTech Connect

This paper reports on a computer code using the multigroup diffusion theory based LEOPARD and ODMUG programs that has been developed to calculate the activity in the coolant leaving the core of a pool-type research reactor. Using this code, the dose rates at various locations along the coolant path with varying coolant flow rate and reactor power perturbations are determined. A flow rate decrease from 1000 to 145 m{sup 3}/h is considered. The results indicate that a flow rate decrease leads to an increase in the coolant outlet temperature, which affects the neutron group constants and hence the group fluxes. The activity in the coolant leaving the core increases with flow rate decrease. However, at the inlet of the holdup tank, the total dose rate first increases, then passes through a maximum at {approximately} 500 m{sup 3}/h, and finally decreases with flow rate decrease. The activity at the outlet of the holdup tank is mainly due to {sup 24}Na and {sup 56}Mn, and it increases by {approximately} 2% when the flow rate decreases from 1000 to 145 m{sup 3}/h. In an accidental power rise at constant flow rate, the activity in the coolant increases, and the dose rates at all the points along the coolant path show a slight nonlinear rise as the reactor power density increases.

Mirza, N.M.; Mirza, S.M.; Ahmad, N. (Centre for Nuclear Studies, Nilore, Islamabad (PK))

1991-12-01

89

Influence of HTR core inlet and outlet temperatures on hydrogen generation efficiency using the sulfur-iodine water-splitting cycle  

SciTech Connect

The performance of hydrogen production via thermochemical cycles is typically evaluated using thermal efficiency. In this study, the sulfur-iodine cycle with heat supplied by a high-temperature reactor (HTR) is analyzed. Two cases are examined: one flow sheet designed by General Atomics in the United States, the other by Commissariat a l'energie atomique et aux energies alternatives in France. In each case, HTR helium inlet and outlet temperatures are specified. Differences in these temperature specifications lead to process variations between the limy sheets and in how the hydrogen processes interface with the nuclear heat source. Two principal conclusions result from the analysis. First, the thermal efficiency tends to plateau above a certain outlet helium temperature. This is a characteristic effect of the method of Ozturk et al. for sulfuric acid decomposition. Second, it is clear that it is impractical to discuss efficiencies for the hydrogen process that are independent of defined operating parameters of the HTR. (authors)

Buckingham, Robert; Brown, Lloyd; Russ, Ben [Gen Atom Co, San Diego, CA 92121 (United States); Lovera, Patrick; Carles, Philippe; Borgard, Jean-Marc; Yvon, Pascal [CEA, DEN, F-91191 Gif Sur Yvette, (France)

2012-04-15

90

Effects of turbulence model on convective heat transfer of coolant flow in a prismatic very high temperature reactor core  

SciTech Connect

The existing study of Spall et al. shows that only {nu}{sup 2}-f turbulence model well matches with the experimental data of Shehata and McEligot which were obtained under strongly heated gas flows. Significant over-predictions in those literatures were observed in the convective heat transfer with the other famous turbulence models such as the k-{epsilon} and k-{omega} models. In spite of such good evidence about the performance of the{nu}{sup 2}-f model, the application of the {nu}{sup 2}-f model to the thermo-fluid analysis of a prismatic core is very rare. In this paper, therefore, the convective heat transfer of the coolant flow in a prismatic core has been investigated using the {nu}{sup 2}-f model. Computational fluid dynamics (CFD) calculations have been carried out for the typical unit cell geometry of a prismatic fuel column with typical operating conditions of prismatic designs. The tested Reynolds numbers of the coolant flow are 10,000, 20,000, 30,000 and 50,000. The predicted Nusselt numbers with the {nu}{sup 2}-f model are compared with the results by the other turbulence models (k-{epsilon} and SST) as well as the empirical correlations. (authors)

Lee, S. N.; Tak, N. I.; Kim, M. H.; Noh, J. M. [Korea Atomic Energy Research Inst., Daedeok-daero 989-11, Yuseong-gu, Daejeon (Korea, Republic of)

2012-07-01

91

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

2010-06-01

92

Measuring flow and pressure of lithium coolant under developmental testing of a high-temperature cooling system of a space nuclear power plant  

NASA Astrophysics Data System (ADS)

Sub-megawatt space NPP use lithium as a coolant and niobium alloy as a structural material. In order to refine the lithium-niobium technology of the material and design engineering, lithium-niobium loops were worked out in RSC Energia, and they were tested at a working temperature of lithium equal to 1070-1300 K. In order to measure the lithium flow and pressure, special gauges were developed, which made possible the calibration and checkout of the loops without their dismantling. The paper describes the architecture of the electromagnetic flowmeter and the electromagnetic vibrating-wire pressure transducer (gauge) for lithium coolant in the nuclear power plant cooling systems. The operating principles of these meters are presented. Flowmeters have been developed for channel diameters ranging from 10 to 100 mm, which are capable of measuring lithium flows in the range of 0.1 to 30 L/s with the error of 3% for design calibration and 1% for volume graduation. The temperature error of the pressure transducers does not exceed 0.4% per 100 K; the nonlinearity and hysteresis of the calibration curve do not exceed 0.3 and 0.4%, respectively. The transducer applications are illustrated by the examples of results obtained from tests on the NPP module mockup and heat pipes of a radiation cooler.

Sobolev, V. Ya.; Sinyavsky, V. V.

2014-12-01

93

Optimizations of packed sorbent and inlet temperature for large volume-direct aqueous injection-gas chromatography to determine high boiling volatile organic compounds in water.  

PubMed

For the expanded application area, fast trace analysis of certain high boiling point (i.e., 150-250 °C) volatile organic compounds (HVOCs) in water, a large volume-direct aqueous injection-gas chromatography (LV-DAI-GC) method was optimized for the following parameters: packed sorbent for sample on-line pretreatment, inlet temperature and detectors configuration. Using the composite packed sorbent self-prepared with lithium chloride and a type of diatomite, the method enabled safe injection of an approximately 50-100 ?L sample at an inlet temperature of 150 °C in the splitless mode and separated HVOCs from water matrix in 2 min. Coupled with a flame ionization detector (FID), an electron capture detector (ECD) and a flame photometric detector (FPD), the method could simultaneously quantify 27 HVOCs that belong to seven subclasses (i.e., halogenated aliphatic hydrocarbons, chlorobenzenes, nitrobenzenes, anilines, phenols, polycyclic aromatic hydrocarbons and organic sulfides) in 26 min. Injecting a 50 ?L sample without any enrichment step, such as cryotrap focusing, the limits of quantification (LOQs) for the 27 HVOCs was 0.01-3 ?g/L. Replicate analyses of the 27 HVOCs spiked source and river water samples exhibited good precision (relative standard deviations ? 11.3%) and accuracy (relative errors ? 17.6%). The optimized LV-DAI-GC was robust and applicable for fast determination and automated continuous monitoring of HVOCs in surface water. PMID:24997514

Yu, Bofan; Song, Yonghui; Han, Lu; Yu, Huibin; Liu, Yang; Liu, Hongliang

2014-08-22

94

Lead Coolant Test Facility Systems Design, Thermal Hydraulic Analysis and Cost Estimate  

SciTech Connect

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 coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimate. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

Soli Khericha; Edwin Harvego; John Svoboda; Ryan Dalling

2012-01-01

95

Directly connected heat exchanger tube section and coolant-cooled structure  

DOEpatents

A cooling apparatus for an electronics rack is provided which includes an air-to-liquid heat exchanger, one or more coolant-cooled structures and a tube. The heat exchanger, which is associated with the electronics rack and disposed to cool air passing through the rack, includes a plurality of distinct, coolant-carrying tube sections, each tube section having a coolant inlet and a coolant outlet, one of which is coupled in fluid communication with a coolant loop to facilitate flow of coolant through the tube section. The coolant-cooled structure(s) is in thermal contact with an electronic component(s) of the rack, and facilitates transfer of heat from the component(s) to the coolant. The tube connects in fluid communication one coolant-cooled structure and the other of the coolant inlet or outlet of the one tube section, and facilitates flow of coolant directly between that coolant-carrying tube section of the heat exchanger and the coolant-cooled structure.

Chainer, Timothy J; Coico, Patrick A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Steinke, Mark E

2014-04-01

96

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

97

Development of Wing Inlets  

NASA Technical Reports Server (NTRS)

Lift, drag, internal flow, and pressure distribution measurements were made on a low-drag airfoil incorporating various air inlet designs. Two leading-edge air inlets are developed which feature higher lift coefficients and critical Mach than the basic airfoil. Higher lift coefficients and critical speeds are obtained for leading half of these inlet sections but because of high suction pressures near exist, slightly lower critical speeds are obtained for the entire inlet section than the basic airfoil.

Racisz, Stanley F.

1946-01-01

98

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

99

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

100

Experimental Surveys for Submerged Inlet  

NASA Astrophysics Data System (ADS)

The objective of the study is to define the Pareto set of designs for a subsonic submerged inlet that minimizes flow distortion and swirl at the engine face. A series of experimental surveys are performed to validate the accompanying computations and to provide additional information regarding the Pareto set. A stainless steel model with a removable submerged inlet (built using an FDM system) has been fabricated and installed in the Rutgers University subsonic wind tunnel. Boundary layer measurements upstream of the inlet are obtained by a computer-controlled traversing pitot tube. The estimated boundary layer thickness agrees closely with the computed profile. Detailed experiments are focused on the measurement of total pressure three diameters downstream of the exit of the inlet. A rotating multi-element pitot rack is fabricated and installed in the model, which is attached to the suction side of a blower to yield the appropriate mass flow rate through the inlet. Motion control, pressure and temperature data acquisition as well as management of the wind tunnel operations for all experiments are controlled by a LabView program developed at Rutgers University.

Jovanovic, Vasilije; Taskinoglu, Ezgi; Elliott, Gregory; Knight, Doyle

2003-11-01

101

Lead Coolant Test Facility - Design Concept and Requirements  

SciTech Connect

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 of current world lead or lead-bismuth test facilities and research need listed in the Generation IV Roadmap, five broad areas of requirements are identified in this paper: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing Across these five broad areas are supported by twenty-one specific requirements. The purpose of this facility is to focus the lead fast reactor community domestically on the requirements for the next unique state of the art test facility. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

Soli Khericha, Ph. D.

2011-08-01

102

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

103

Effect of porosity and the inlet heat transfer fluid temperature variation on the performance of cool thermal energy storage system  

Microsoft Academic Search

This paper discusses the results of numerical and experimental study of an encapsulated cool thermal energy storage system.\\u000a The storage system is a cylindrical storage tank filled with phase change material encapsulated in spherical container, placed\\u000a in a refrigeration loop. A simulation program was developed to evaluate the temperature histories of the heat transfer fluid\\u000a and the phase change material

M. Cheralathan; R. Velraj; S. Renganarayanan

2007-01-01

104

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

105

Hydrodynamic, thermal, and thermophysical characteristics of some porous materials in high-temperature flows and coolant gas injection  

NASA Astrophysics Data System (ADS)

Knowledge of the accurate hydrodynamical and thermophysical constants of porous materials and their dependence on temperature, porosity, and other parameters is essential in theoretical studies concerned with the strength, filtration, and thermophysical characteristics of porous materials used for the thermal protection of structures. Here, some of these constants are determined on the basis of wind-tunnel test results. The principal parameters of several porous materials (including materials based on stainless steel, nichrome, metal ceramics, molybdenum, and tungsten) are presented.

Golovanov, A. N.

1992-06-01

106

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

107

PURIFICATION OF HELIUM COOLANT  

Microsoft Academic Search

The literature from 1955 to 1961 on the purification of helium coolant, ; especially on the separatiqn of fission gases, is reviewed. The principle of gas ; purification, the separation of radioactive and nonradioactive gases, and ; purification systems for helium coolant are covered. 184 references. (D.C.W.)

K. Oshima; K. Naito; K. Nishida

1963-01-01

108

Assessment of the Use of Nitrogen Trifluoride for Purifying Coolant and Heat Transfer Salts in the Fluoride Salt-Cooled High-Temperature Reactor  

SciTech Connect

This report provides an assessment of the use of nitrogen trifluoride for removing oxide and water-caused contaminants in the fluoride salts that will be used as coolants in a molten salt cooled reactor.

Scheele, Randall D.; Casella, Andrew M.

2010-09-28

109

Attic Inlet Technology Update  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

110

Stepped inlet optical panel  

DOEpatents

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

Veligdan, James T. (6 Stephanie La., Manorville, NY 11949)

2001-01-01

111

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

112

Lead Coolant Test Facility Technical and Functional Requirements, Conceptual Design, Cost and Construction Schedule  

SciTech Connect

This report presents 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 of current world lead or lead-bismuth test facilities and research need listed in the Generation IV Roadmap, five broad areas of requirements of basis are identified: Develop and Demonstrate Prototype Lead/Lead-Bismuth Liquid Metal Flow Loop Develop and Demonstrate Feasibility of Submerged Heat Exchanger Develop and Demonstrate Open-lattice Flow in Electrically Heated Core Develop and Demonstrate Chemistry Control Demonstrate Safe Operation and Provision for Future Testing. These five broad areas are divided into twenty-one (21) specific requirements ranging from coolant temperature to design lifetime. An overview of project engineering requirements, design requirements, QA and environmental requirements are also presented. The purpose of this T&FRs is to focus the lead fast reactor community domestically on the requirements for the next unique state of the art test facility. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 420oC. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M. It is also estimated that the facility will require two years to be constructed and ready for operation.

Soli T. Khericha

2006-09-01

113

MACHINE COOLANT WASTE REDUCTION BY OPTIMIZING COOLANT LIFE  

EPA Science Inventory

Machine shops use coolants to improve the life and function of machine tools. hese coolants become contaminated with oils with use, and this contamination can lead to growth of anaerobic bacteria and shortened coolant life. his project investigated methods to extend coolant life ...

114

Correlation of Forced-convection Heat-transfer Data for Air Flowing in Smooth Platinum Tube with Long-approach Entrance at High Surface and Inlet-air Temperatures  

NASA Technical Reports Server (NTRS)

A heat-transfer investigation was conducted with air in an electrically heated platinum tube with long-approach entrance, inside diameter of 0.525 inch, and effective heat-transfer length of 24 inches over ranges of Reynolds number up to 320,000, average inside-tube-wall temperature up to 3053 degrees R, and inlet-air temperature up to 1165 degrees R. Correlation of data by the conventional Nusselt relation resulted in separation of data with tube-wall temperature. Good correlation was obtained, however, by use of a modified Reynolds number.

Desmon, Leland G; Sams, Eldon W

1950-01-01

115

Flow boiling with enhancement devices for cold plate coolant channel design  

NASA Technical Reports Server (NTRS)

The use of flow boiling for thermal energy transport is intended to provide an alternative for accommodating higher heat fluxes in commercial space systems. The objectives are to: (1) examine the variations in both the mean and local (axial and circumferential) heat transfer coefficients for a circular coolant channel with either smooth walls, spiral fins, or both spiral fins and a twisted tape; (2) examine the effects of channel diameter and subcooling; and (3) develop an improved reduction analysis and/or suggest possible heat transfer correlation of the present data. Freon-11 is the working fluid. Two-dimensional (circumferential and axial) wall temperature distributions were measured for coolant channels with the above noted internal geometries. The flow regimes which are being studied are: (1) single phase; (2) subcooled flow boiling; and (3) stratified flow boiling. The inside diameter of all test sections is near 1.0 cm. Cicumferentially averaged heat transfer coefficients at several axial locations were obtained for selected coolant channels for a mass velocity of 210 kg/sq m s, an exit pressure of 0.19 MPa (absolute), and an inlet subcooling of 20.8 C. Overall (averaged over the entire channel) heat transfer coefficients were compared for the above channel geometries. This comparison showed that the channel with large pitch spiral fins had higher heat transfer coefficients at all power levels.

Boyd, Ronald D., Sr.; Smith, Alvin

1990-01-01

116

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

117

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

118

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

119

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

120

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

121

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

122

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

123

Fuel cell system with coolant flow reversal  

DOEpatents

Method and apparatus for cooling electrochemical fuel cell system components. Periodic reversal of the direction of flow of cooling fluid through a fuel cell stack provides greater uniformity and cell operational temperatures. Flow direction through a recirculating coolant fluid circuit is reversed through a two position valve, without requiring modulation of the pumping component.

Kothmann, Richard E. (Pittsburgh, PA)

1986-01-01

124

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

125

Secondary flow and heat transfer control in gas turbine inlet nozzle guide vanes  

Microsoft Academic Search

Endwall heat transfer is a very serious problem in the inlet nozzle guide vane region of gas turbine engines. To resolve heat transfer concerns and provide the desired thermal protection, modern cooling flows for the vane endwalls tend to be excessive leading to lossy and inefficient designs. Coolant introduction is further complicated by the flow patterns along vane endwall surfaces.

Steven Wayne Burd

1998-01-01

126

The design of an air-cooled metallic high temperature radial turbine  

NASA Technical Reports Server (NTRS)

Recent trends in small advanced gas turbine engines call for higher turbine inlet temperatures. Advances in radial turbine technology have opened the way for a cooled metallic radial turbine capable of withstanding turbine inlet temperatures of 2500 F while meeting the challenge of high efficiency in this small flow size range. In response to this need, a small air-cooled radial turbine has been designed utilizing internal blade coolant passages. The coolant flow passage design is uniquely tailored to simultaneously meet rotor cooling needs and rotor fabrication constraints. The rotor flow-path design seeks to realize improved aerodynamic blade loading characteristics and high efficiency while satisfying rotor life requirements. An up-scaled version of the final engine rotor is currently under fabrication and, after instrumentation, will be tested in the warm turbine test facility at the NASA Lewis Research Center.

Snyder, Philip H.; Roelke, Richard J.

1988-01-01

127

Optimization of flow uniformity at the CFFF superheater inlet  

NASA Astrophysics Data System (ADS)

Equations governing the turbulent, incompressible flow in a T-shaped duct which consists of an ash/seed hopper and an inlet transition section are solved by means of a 2D finite-difference numerical procedure. The effects of inlet velocity profile, bulk temperature, wall roughness, inlet mass flow rate, water level in the ash/seed hopper, and geometric configuration on the flow uniformity at the superheater inlet are examined. The nonuniformity of the flow is expected to reduce the efficiency of the superheater. The flow uniformity is indicated by an optimization index which varies increasingly with flow nonuniformity. The optimization index at the superheater inlet for the existing module is 62.53 percent. It is found that an optimization index with a value of 30.74 percent can be obtained by using the present numerical modeling.

Lee, J. J.

1992-01-01

128

Design of bioaerosol sampling inlets  

E-print Network

.22, and 6.67 m/s), and characterized for particle sizes between 5 and 20 �µm AD. The base-line ambient sampling inlet, which operates at 100 L/min, was developed to interface with a Circumferential Slot Virtual Impactor aerosol concentrator. The inlet...

Nene, Rohit Ravindra

2007-09-17

129

Experimental Surveys for Submerged Inlet  

Microsoft Academic Search

The objective of the study is to define the Pareto set of designs for a subsonic submerged inlet that minimizes flow distortion and swirl at the engine face. A series of experimental surveys are performed to validate the accompanying computations and to provide additional information regarding the Pareto set. A stainless steel model with a removable submerged inlet (built using

Vasilije Jovanovic; Ezgi Taskinoglu; Gregory Elliott; Doyle Knight

2003-01-01

130

Performance of supersonic scoop inlets  

NASA Technical Reports Server (NTRS)

A brief summary is made of the performance of a series of variable-geometry type scoop inlets investigated at the Lewis Laboratory on a model of the X-3 airplane fuselage. Data are presented for a range of inlet mass-flow ratios over a Mach number range from 0 to 2 and from 0 degrees to 12 degrees angle of attack. Rounded-lip inlets are found to give satisfactory performance to a Mach number of 1.5. Use of sharp rather than blunt lip configurations is shown to provide considerable gains in available thrust at Mach number 2.0 but penalize take-off performance to the extent that auxiliary air intakes may be required. No one inlet type was found to be superior over the entire range of operating variables. Thus, the choice of a specific inlet design will be influenced by structural and mechanical as well as aerodynamic considerations.

Weinstein, Maynard I

1952-01-01

131

Combustion Gas Turbine Power Enhancement by Refrigeration of Inlet Air  

E-print Network

COOLING Another method of cooling gas turbine inlet air is to bleed some of the air from the compressor discharge, expand this through an air turbine and mix the expander air with the inlet air to the compressor thus reducing the overall inlet... temperature. Expan sion cooling has been discussed in [7] [8]. A typical cycle for such a system is shown in Figure 9. The system includes an intercooler and a regene rator. A suction valve is provided to control the amount of bleed air. The results...

Meher-Homji, C. B.; Mani, G.

1983-01-01

132

Effect on cold starting performance of an exhaust gas to engine coolant heat exchanger in an automobile  

SciTech Connect

The effect of exhaust-to-coolant heat exchange on fuel economy and cab heater performance during cold start was studied using a 1981 Ford Granada automobile and a 1977 Buick V-6 engine on a test stand. The ambient soaking temperatures ranged from 35 to -15 degrees Fahrenheit. It was found that fuel used in a 7 minute warm up run of the test stand engine was less by 2.1 to 4.6% when the heat exchanger replaced the muffler in the system. Likewise for the Granada, fuel consumption was less by 2.8 to 3.8% over an in town test route and less by 1.5 to 1.8% on a highway test route, when the heat exchanger replaced the muffler. Similarly, the time required for the coolant at the inlet of the cab heater to reach a temperature of 180 Fahrenheit was 27.5 to 28.8% shorter for the test stand engine, 6.3 to 7.0% shorter for the Granada in town route and 16.6 to 16.9% shorter for the Granada highway route, when the heat exchanger replaced the muffler.

Goettler, H.J.; Vidger, L.J.

1983-05-01

133

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. This includes a description of the hardware and techniques employed, and a summary of the highlights of experimental investigations and analytical modeling. Distortion devices successfully simulated inlet distortion, and knowledge was gained about compression system response to different types of distortion. A list of NASA research references is included.

Biesiadny, T. J.; Braithwaite, W. M.; Soeder, R. H.; Abdelwahab, M.

1986-01-01

134

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

NASA Technical Reports Server (NTRS)

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

Lewis, James P.

1953-01-01

135

TBCC Inlet Experiments and Analysis  

NASA Technical Reports Server (NTRS)

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

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

2007-01-01

136

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

137

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

138

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

139

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

140

Method for Determining Optimum Injector Inlet Geometry  

NASA Technical Reports Server (NTRS)

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

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

2015-01-01

141

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

142

TiAl Scramjet Inlet Flap Subelement Designed and Fabricated  

NASA Technical Reports Server (NTRS)

Next-generation launch vehicles are being designed with turbine-based combined cycle (TBCC) propulsion systems having very aggressive thrust/weight targets and long lives. Achievement of these goals requires advanced materials in a wide spectrum of components. TiAl has been identified as a potential backstructure material for maintainable composite panel heat exchangers (HEX) in the inlet, combustor, and nozzle section of a TBCC propulsion system. Weight reduction is the primary objective of this technology. Design tradeoff studies have assessed that a TiAl structure, utilizing a high-strength, hightemperature TiAl alloy called Gamma MET PX,1 reduce weight by 41 to 48 percent in comparison to the baseline Inconel 718 configuration for the TBCC propulsion system inlet, combustor, and nozzle. A collaborative effort between the NASA Glenn Research Center, Pratt & Whitney, Engineering Evaluation & Design, PLANSEE AG (Austria), and the Austrian Space Agency was undertaken to design, manufacture, and validate a Gamma-MET PX TiAl structure for scramjet applications. The TiAl inlet flap was designed with segmented flaps to improve manufacturability, to better control thermal distortion and thermal stresses, and to allow for maintainable HEX segments. The design philosophy was to avoid excessively complicated shapes, to minimize the number of stress concentrations, to keep the part sizes reasonable to match processing capabilities, and to avoid risky processes such as welding. The conceptual design used a standard HEX approach with a double-pass coolant concept for centrally located manifolds. The flowpath side was actively cooled, and an insulation package was placed on the external side to save weight. The inlet flap was analyzed structurally, and local high-stress regions were addressed with local reinforcements.

Draper, Susan L.

2004-01-01

143

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

144

Radial coolant channels fabricated by simplified method  

NASA Technical Reports Server (NTRS)

Radial coolant channels for distributing a coolant over the inner wall of a circular section are fabricated by cold-rolling indentations on the inside circumference of the base section and covering the indentations with a rolled flange.

Freeman, A.

1966-01-01

145

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

146

A method for measuring cooling air flow in base coolant passages of rotating turbine blades  

NASA Technical Reports Server (NTRS)

Method accurately determines actual coolant mass flow rate in cooling passages of rotating turbine blades. Total and static pressures are measured in blade base coolant passages. Mass flow rates are calculated from these measurements of pressure, measured temperature and known area.

Liebert, C. H.; Pollack, F. G.

1975-01-01

147

Transpiration cooling using air as a coolant  

SciTech Connect

Transpiration cooling is one of the most effective techniques for protecting a surface exposed to a high-temperature gas stream. In the present paper, the transpiration cooling effectiveness was measured under steady state. Air as a coolant was transpired from the surface of a porous plate exposed to hot gas stream, and the transpiration rate was varied in the range of 0.001 [approximately] 0.006. The transpiration cooling effectiveness was evaluated by measuring the temperature of the upper surface of the plate. Also, a theoretical study was performed and it was clarified that the effectiveness increases with increasing transpiration rate and heat-transfer coefficient of the upper surface. Further, the effectiveness was expressed as a function of the blowing parameter only. The agreement between the experimental results and theoretical ones was satisfactory.

Kikkawa, Shinzo; Senda, Mamoru; Sakagushi, Katsuji; Shibutani, Hideki (Doshisha Univ., Kyoto (Japan))

1993-02-01

148

Meeting Review: Airborne Aerosol Inlet Workshop  

NASA Technical Reports Server (NTRS)

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

Baumgardner, Darrel; Huebert, Barry; Wilson, Chuck

1991-01-01

149

Flow behavior in inlet guide vanes of radial turbines  

NASA Technical Reports Server (NTRS)

Scroll flow is discussed. Streamline pattern and velocity distribution in the guide vanes are calculated. The blade surface temperature distribution is also determined. The effects of the blade shapes and the nozzle channel width on the velocity profiles at inlet to the guide vanes are investigated.

Sokhey, J.; Tabakoff, W.; Hosny, W. M.

1975-01-01

150

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

151

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 experimenal 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, Charles E., Jr.; Huebner, Lawrence D.

1991-01-01

152

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

NASA Technical Reports Server (NTRS)

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

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

1978-01-01

153

Thermal analysis of engine inlet anti-icing systems  

NASA Technical Reports Server (NTRS)

A hot air anti-icing system of a gas turbine engine inlet is analyzed numerically. A three-dimensional potential flow code, which accounts for compressibility effects, is used to determine the flowfield in and around the inlet. A particle trajectory code is developed using a local linearization technique. The trajectory code is used to calculate local water impingement rates. Energy balances are performed on both the surface runback water and the metallic skin to determine their temperature distributions. A variety of test cases are considered in order to validate the various numerical components of the process as well as to demonstrate the procedure.

Keith, Theo G., Jr.; De Witt, Kenneth J.; Nathman, James K.; Dietrich, Donald A.; Al-Khalil, Kamel M.

1989-01-01

154

Scramjet including integrated inlet and combustor  

SciTech Connect

This patent describes a scramjet engine. It comprises: a first surface including an aft facing step; a cowl including: a leading edge and a trailing edge; an upper surface and a lower surface extending between the leading edge and the trailing edge; the cowl upper surface being spaced from and generally parallel to the first surface to define an integrated inlet-combustor therebetween having an inlet for receiving and channeling into the inlet-combustor supersonic inlet airflow; means for injecting fuel into the inlet-combustor at the step for mixing with the supersonic inlet airflow for generating supersonic combustion gases; and further including a spaced pari of sidewalls extending between the first surface to the cowl upper surface and wherein the integrated inlet-combustor is generally rectangular and defined by the sidewall pair, the first surface and the cowl upper surface.

Kutschenreuter, P.H. Jr.; Blanton, J.C.

1992-02-04

155

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

156

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

157

Cleaning of aluminum after machining with coolants  

SciTech Connect

An x-ray photoemission spectroscopic study was undertaken to compare the cleaning of the Advanced Photon Source (APS) aluminum extrusion storage ring vacuum chambers after machining with and without water soluble coolants. While there was significant contamination left by the coolants, the cleaning process was capable of removing the residue. The variation of the surface and near surface composition of samples machined either dry or with coolants was negligible after cleaning. The use of such coolants in the machining process is therefore recommended.

Roop, B.

1995-07-01

158

Radial inlet guide vanes for a combustor  

DOEpatents

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

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

2013-02-12

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

Axisymmetric inlet minimum weight design method  

NASA Technical Reports Server (NTRS)

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

Nadell, Shari-Beth

1995-01-01

161

Computational study of fuel injection in a shcramjet inlet  

NASA Astrophysics Data System (ADS)

The primary objective of this investigation is to present the mixing of fuel with air in the inlet of a shock-induced combustion ramjet (shcramjet). The study is limited to non-reacting hydrogen-air mixing in an external-compression inlet at a flight Mach number of 11 and at a dynamic pressure of 1400 psf (67032 Pa), using an array of cantilevered ramp injectors. A numerical method based on the Yee-Roe scheme and block-implicit approximate factorization is developed to solve the FANS equations closed by the Wilcox ko turbulence model. A new acceleration technique for streamwise-separated hypersonic flow, dubbed the "marching window", is presented. The dilatational dissipation correction is seen to affect the mixing efficiency considerably for a cantilevered ramp injector flowfield even at a vanishing convective Mach number, due to the high turbulent Mach number generated by the high cross-stream shear induced by the ramp-generated axial vortices. Due to the fuel being injected at a very high speed, fuel injection in the inlet is found to increase considerably the thrust potential, with a gain exceeding the loss by 40--120%. Losses due to skin friction are seen to play a significant role in the inlet, as they are estimated to make up as much as 50--70% of the thrust potential losses. The use of a turbulence model that can predict accurately the wall shear stress is hence crucial in assessing the losses accurately in a shcramjet inlet. Substituting the second inlet shock by a Prandtl-Meyer compression fan is encouraged as it decreases the thrust potential losses, reduces the risk of premature ignition by reducing the static temperature, while decreasing the mixing efficiency by a mere 6%. One approach that is observed herein to be successful at increasing the mixing efficiency in the inlet is by alternating the injection angle along the injector array. The use of two injection angles of 9 and 16 degrees is seen to result in a 32% increase in the mixing efficiency at the expense of a 14% increase in the losses when compared to a single injection angle of 10 degrees. Using alternating injection angles, the mixing efficiency reaches as much as 0.47 at the inlet exit.

Parent, Bernard

162

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

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

Corrosion of structural materials by lead-based reactor coolants.  

SciTech Connect

Advanced nuclear reactor design has, in recent years, focused increasingly on the use of heavy-liquid-metal coolants, such as lead and lead-bismuth eutectic. Similarly, programs on accelerator-based transmutation systems have also considered the use of such coolants. Russian experience with heavy-metal coolants for nuclear reactors has lent credence to the validity of this approach. Of significant concern is the compatibility of structural materials with these coolants. We have used a thermal convection-based test method to allow exposure of candidate materials to molten lead and lead-bismuth flowing under a temperature gradient. The gradient was deemed essential in evaluating the behavior of the test materials in that should preferential dissolution of components of the test material occur we would expect dissolution in the hotter regions and deposition in the colder regions, thus promoting material transport. Results from the interactions of a Si-rich mild steel alloy, AISI S5, and a ferritic-martensitic stainless steel, HT-9, with the molten lead-bismuth are presented.

Abraham, D. P.; Leibowitz, L.; Maroni, V. A.; McDeavitt, S. M.; Raraz, A. G.

2000-11-16

165

An experimental investigation of the post-CHF enhancement factor for a prototypical ITER divertor plate with water coolant  

SciTech Connect

In an off-normal event, water-cooled copper divertor plates in the International Thermonuclear Experimental Reactor (ITER) may either experience heat loads beyond their design basis, or the normal heat loads may be accompanied by low coolant pressure and velocity. The purpose of this experiment was to illustrate that during one-sided heating, as in ITER, a copper divertor plate with the proper side wall thickness, at low system pressure and velocity can absorb without failing an incident heat flux, q{sub i}, that significantly exceed the value, q{sub i}{sup CHF}, which is associated with local CHF at the wall of the coolant channel. The experiment was performed using a 30 KW electron beam test system for heating of a square cross-section divertor heat sink with a smooth circular channel of 7.6 mm diameter. The heated width, length, and wall thickness were 16, 40, and 3 mm, respectively. Stable surface temperatures were observed at incident heat fluxes greater than the local CHF point, presumably due to circumferential conduction around the thick tube walls when q{sub i}{sup CHF} was exceeded. The Post-CHF enhancement factor, {eta}, is defined as the ratio of the incident burnout heat flux, q{sub i}{sup BO}, to q{sub i}{sup CHF}. For this experiment with water at inlet conditions of 70 C, 1 m/s, and 1 MPa, q{sub i}{sup CHF} and q{sub i}{sup BO} were 600 and 1,100 W/cm{sup 2}, respectively, which gave an {eta} of 1.8.

Marshall, T.D. [Rensselaer Polytechnic Inst., Troy, NY (United States); Watson, R.D.; McDonald, J.M.; Youchison, D.L. [Sandia National Labs., Albuquerque, NM (United States)

1995-12-31

166

An experimental investigation of the post-CHF enhancement factor for a prototypical ITER divertor plate with water coolant  

SciTech Connect

In an off-normal event, water-cooled copper divertor plates in the International Thermonuclear Experimental Reactor (ITER) may either experience heat loads beyond their design basis, or the normal heat loads may be accompanied by low coolant pressure and velocity. The purpose of this experiment was to illustrate that during one-sided heating, as in ITER, a copper divertor plate with the proper side wall thickness, at low system pressure and velocity can absorb without failing an incident heat flux, q{sub i}, that significantly exceed the value, q{sub i}{sup CHF}, which is associated with local CHF at the wall of the coolant channel. The experiment was performed using a 30 kW electron beam test system for heating of a square cross-section divertor heat sink with a smooth circular channel of 7.63 mm diameter. The heated width, length, and wall thickness were 16, 40, and 3 mm, respectively. Stable surface temperatures were observed at incident heat fluxes greater than the local CHF point, presumably due to circumferential conduction around the thick tube walls when q{sub i}{sup CHF} was exceeded. The Post-CHF enhancement factor, {eta}, is defined as the ratio of the incident burnout heat flux, q{sub i}{sup BO}, to q{sub i}{sup CHF}. For this experiment with water at inlet conditions of 70{degrees}C, 1 m/s, and 1 MPa, q{sub i}{sup CHF} and q{sub i}{sup BO} were 600 and 1100 W/cm{sup 2}, respectively, which gave an {eta} of 1.8.

Marshall, T.D. [Rensselaer Polytechnic Institute, Troy, NY (United States); Watson, R.D.; McDonald, J.M. [Sandia National Lab., Albuquerque, NM (United States)] [and others

1995-09-01

167

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

168

Experimental investigation of a submerged subsonic inlet  

NASA Astrophysics Data System (ADS)

The goal of combined computational and experimental study is the design optimization of a generic submerged inlet, which minimizes flow distortion at the engine face. A series of experimental surveys were performed to validate the accompanying computations and to provide additional information regarding the Pareto Set of optimal designs. The objectives of experimental investigation are to: (1) perform comparison between experimental and accompanying computed Distortion Coefficients (DC) for the baseline and one of the inlets from the Pareto Set of optimal designs for zero angle of attack and angle of sideslip, (2) assess the sensitivity of the measured DC's for both inlets for nonzero angle of attack and angle of sideslip and (3) examine the flowfield structure (mean velocity and turbulence levels within inlets). Detailed experiments using pressure differential technique (with the accuracy of +/-3%) were focused on the measurements of total pressure three diameters downstream of the exit of the inlet. A hot wire thermal anemometry system was employed to verify velocity profiles obtained using the pressure differential technique and to assess the sensitivity of the turbulence structure to the change in inlet geometry. The accuracy of those measurements was +/-5%. Experimental evaluation of the baseline and optimum inlet for zero angle of attack and yaw showed a consistent trend between experimental and computational results in reduction of the DC. Also, the DC improved for the optimum inlet compared to the baseline inlet for negative angles of attack and all yaw angles. The optimum inlet, which introduced fins within the inlet, decreased the turbulence levels for zero and negative and increased turbulence levels for positive angles of attack (consistent with the DC). In addition, the experimental evaluations for nonzero angles of attack and yaw were performed with minimum additional effort, much faster than it would take to perform the corresponding computational study.

Jovanovic, Vasilije J.

169

SAFEGUARDS ASPECTS OF PWR REACTOR COOLANT CHEMISTRY  

Microsoft Academic Search

In the Pressurized Water Reactor (PWR) light water serves as both ; moderator and as coolant. The water at the same time participates in a variety ; of chemical process of concern in the design and operation of the reactor. These ; include corrosion of the primary coolant system, mechanisms, and fuel elements; ; radiation chemical reactions involving dissociation and

1957-01-01

170

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

171

Lake Worth Inlet Palm Beach Harbor  

E-print Network

#12;1 Lake Worth Inlet Palm Beach Harbor Palm Beach County, Florida Integrated Feasibility Report, was engaged to conduct the IEPR of the Lake Worth Inlet, Palm Beach Harbor Integrated Feasibility Report and recent rates was added to Section 4.2.3. Clarification on the grouping of asphalt, fuel oil

US Army Corps of Engineers

172

Comparison of flow rates and pressure profiles for N-sequential inlets and three related seal configurations  

SciTech Connect

Experimental and analytical results are presented for choked flows of fluid nitrogen over a range of reduced inlet stagnation temperatures (from 0.67 to ambient) and reduced inlet stagnation pressures to 2. Flow rate and pressure profile comparisons are made between N aligned sequential orifice inlets, a 33-tooth labyrinth seal, a 3-step seal, a cylindrical seals and the classic venturi. Seal effectiveness appears strongly dependent on upstream losses and geometry configuration.

Hendricks, R.C.

1983-08-01

173

Electrically heated particulate matter filter with recessed inlet end plugs  

DOEpatents

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

Gonze, Eugene V. (Pinckney, MI); Ament, Frank (Troy, MI)

2012-02-21

174

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

175

14 CFR 25.941 - Inlet, engine, and exhaust compatibility.  

Code of Federal Regulations, 2014 CFR

... General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both— (a) The system comprised of the inlet, engine (including thrust augmentation systems, if...

2014-01-01

176

14 CFR 25.941 - Inlet, engine, and exhaust compatibility.  

Code of Federal Regulations, 2010 CFR

... General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both— (a) The system comprised of the inlet, engine (including thrust augmentation systems, if...

2010-01-01

177

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

178

Bi-coolant flat plate solar collector  

NASA Astrophysics Data System (ADS)

The feasibility study of a flat plate solar collector which heats air and water concurrently or separately was carried out. Air flows above the collector absorber plate, while water flows in tubes soldered or brazed beneath the plate. The collector efficiencies computed for the flow of both air and water are compared with those for the flow of a single coolant. The results show that the bi-coolant collector efficiency computed for the entire year in Buffalo, New York is higher than the single-coolant collector efficiency, although the efficiency of the water collector is higher during the warmer months.

Chon, W. Y.; Green, L. L.

179

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

180

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

181

Power Augmentation Study of a Combined Cycle Power Plant Using Inlet Fogging  

NASA Astrophysics Data System (ADS)

The power output of gas turbines decreases as a result of increased ambient temperature. One way to recover the output loss is to cool the inlet air. In Taiwan, most gas turbines operate with combined cycle for base load. Only a small portion operates with simple cycle for peak load. Therefore, the power augmentation strategies for combined cycle power plants need to be studied in advance in order to recover the power loss due to increased ambient temperature in hot summer days. The objective of this research is to study the effects caused by adding an inlet fogging system to an existing gas turbine-based combined cycle plant. Moreover, this paper also includes a parametric study of plant performance with different effectiveness of the inlet fogging system based on the average ambient conditions. Results from this study can be used as a guideline for combined cycle power augmentation using inlet fogging.

Chiang, Hsiao-Wei; Wang, Pai-Yi

182

Airflow control system for supersonic inlets  

NASA Technical Reports Server (NTRS)

In addition to fixed and variable bleed devices provided for controlling the position of a terminal shock wave in a supersonic inlet, a plurality of free piston valves are disposed around the periphery of a cowling of a supersonic engine inlet. The free piston valves are disposed in dump passageways, each of which begin at a bleed port in the cowling that is located in the throat region of the inlet, where the diameter of the centerbody is near maximum, and terminates at an opening in the cowling adjacent a free piston valve. Each valve is controlled by reference pressure.

Mitchell, G. A. (inventor); Sanders, B. W.

1974-01-01

183

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

NASA Technical Reports Server (NTRS)

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

Anderson, Bernhard H.; Weir, Lois

2014-01-01

184

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2010 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...

2010-07-01

185

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2011 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...

2011-07-01

186

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2012 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...

2012-07-01

187

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

188

40 CFR 1065.745 - Coolants.  

Code of Federal Regulations, 2014 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...

2014-07-01

189

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

190

THE KING SALMON OF COOK INLET, ALASKA  

E-print Network

, Alaska ABSTRACT Runs of king salmon (Oncorhynchus tshawytscha) in Cook Inlet, Alaska, are de- clining for spawning. INTRODUCTION Historically, the king salmon (Oncorhynchus tshawytscha) is one of the most

191

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

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

1976-01-01

192

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

193

Effect of inlet and outlet flow conditions on natural gas parameters in supersonic separation process.  

PubMed

A supersonic separator has been introduced to remove water vapour from natural gas. The mechanisms of the upstream and downstream influences are not well understood for various flow conditions from the wellhead and the back pipelines. We used a computational model to investigate the effect of the inlet and outlet flow conditions on the supersonic separation process. We found that the shock wave was sensitive to the inlet or back pressure compared to the inlet temperature. The shock position shifted forward with a higher inlet or back pressure. It indicated that an increasing inlet pressure declined the pressure recovery capacity. Furthermore, the shock wave moved out of the diffuser when the ratio of the back pressure to the inlet one was greater than 0.75, in which the state of the low pressure and temperature was destroyed, resulting in the re-evaporation of the condensed liquids. Natural gas would be the subsonic flows in the whole supersonic separator, if the mass flow rate was less than the design value, and it could not reach the low pressure and temperature for the condensation and separation of the water vapor. These results suggested a guidance mechanism for natural gas supersonic separation in various flow conditions. PMID:25338207

Yang, Yan; Wen, Chuang; Wang, Shuli; Feng, Yuqing

2014-01-01

194

Effect of Inlet and Outlet Flow Conditions on Natural Gas Parameters in Supersonic Separation Process  

PubMed Central

A supersonic separator has been introduced to remove water vapour from natural gas. The mechanisms of the upstream and downstream influences are not well understood for various flow conditions from the wellhead and the back pipelines. We used a computational model to investigate the effect of the inlet and outlet flow conditions on the supersonic separation process. We found that the shock wave was sensitive to the inlet or back pressure compared to the inlet temperature. The shock position shifted forward with a higher inlet or back pressure. It indicated that an increasing inlet pressure declined the pressure recovery capacity. Furthermore, the shock wave moved out of the diffuser when the ratio of the back pressure to the inlet one was greater than 0.75, in which the state of the low pressure and temperature was destroyed, resulting in the re-evaporation of the condensed liquids. Natural gas would be the subsonic flows in the whole supersonic separator, if the mass flow rate was less than the design value, and it could not reach the low pressure and temperature for the condensation and separation of the water vapor. These results suggested a guidance mechanism for natural gas supersonic separation in various flow conditions. PMID:25338207

Yang, Yan; Wen, Chuang; Wang, Shuli; Feng, Yuqing

2014-01-01

195

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

DOEpatents

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

Veligdan, James T. (Manorville, NY); Slobodin, David (28 Independence Ave., Lake Oswego, OR 97035)

2001-01-01

196

Optimal Design of a Subsonic Submerged Inlet  

Microsoft Academic Search

A multi-objective optimization study based on an epsilon-constraint method is conducted for the design optimization of a subsonic submerged air vehicle inlet. The multi-objective optimization problem is reformulated by minimizing one of the objectives and restricting the other objectives within user specified values. The figures of merits are the engine-face distortion and swirl that determines the inlet\\/engine compatibility. The distortion

Ezgi Taskinoglu; Vasilije Jovanovic; Gregory Elliott; Doyle Knight

2003-01-01

197

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

198

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

199

Inlet conditions for large eddy simulation: A review  

Microsoft Academic Search

The treatment of inlet conditions for LES is a complex problem, but of extreme importance as, in many cases, the fluid behaviour within the domain is determined in large part by the inlet behaviour. The reason why it is so difficult to formulate inlet conditions is because the inlet flow must include a stochastically-varying component: ideally this component should ‘look’

G. R. Tabor; M. H. Baba-Ahmadi

2010-01-01

200

Investigation of normal shock inlets for highly maneuverable aircraft  

NASA Technical Reports Server (NTRS)

Concepts are investigated for obtaining both low cowl drag and good inlet performance at high angles of attack. The effect of a canard on inlet performance for a kidney shaped inlet in each of two vertical locations is discussed along with a sharp lip two dimensional inlet on a canardless forebody.

Martin, A. W.

1977-01-01

201

Comparison of Inlet Geometry in Microfluidic Cell Affinity Chromatography  

PubMed Central

Cell separation based on microfluidic affinity chromatography is a widely used methodology in cell analysis research when rapid separations with high purity are needed. Several successful examples have been reported with high separation efficiency and purity; however, cell capture at the inlet area and inlet design has not been extensively described or studied. The most common inlets—used to connect the microfluidic chip to pumps, tubing, etc—are vertical (top-loading) inlets and parallel (in-line) inlets. In this work, we investigated the cell capture behavior near the affinity chip inlet area and compared the different performance of vertical inlet devices and parallel inlet devices. Vertical inlet devices showed significant cell capture capability near the inlet area, which led to the formation of cell blockages as the separation progressed. Cell density near the inlet area was much higher than the remaining channel, while for parallel inlet chips cell density at the inlet area was similar to the rest of the channel. In this paper, we discuss the effects of inlet type on chip fabrication, nonspecific binding, cell capture efficiency, and separation purity. We also discuss the possibility of using vertical inlets in negative selection separations. Our findings show that inlet design is critical and must be considered when fabricating cell affinity microfluidic devices. PMID:21207967

Li, Peng; Tian, Yu; Pappas, Dimitri

2011-01-01

202

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

203

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

204

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

NASA Astrophysics Data System (ADS)

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 supgrsonic 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.

1983-06-01

205

New England tidal inlets with special reference to riverine-associated inlet systems  

Microsoft Academic Search

Tidal inlets along the glaciated coast of New England exhibit a diverse morphology due to widely different physical and geological settings and sediment abundance. Except for the glacial sediment coasts of Cape Cod, Nantucket Island, and Martha's Vineyard, most regions of New England are rocky, and barrier and tidal inlet development is related to isolated glacial and riverine sediment supplies.

D. M FitzGerald; I. V Buynevich; R. A Davis; M. S Fenster

2002-01-01

206

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

207

Vegetable oils: Liquid coolants for solar heating and cooling applications  

NASA Astrophysics Data System (ADS)

Vegetable oils, renewable byproducts of agriculture processes, were investigated for possible use as liquid coolants. Several thermophysical properties of four vegetable oils were investigated. Vapor pressures, specific heat, viscosity, density, and thermal conductivity were determined over a range of temperatures for corn, soybeans, peanut, and cottonseed oil. ASTM standard methods were used for these determinations. In addition, chemical analyses were performed on samples of each oil. The samples were collected before and after each experiment so that any changes in composition could be noted. The tests included iodine number, fatty acid, and moisture content determination.

Ingley, H. A.

1980-02-01

208

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

209

Anatomoechocardiographic correlation double inlet left ventricle.  

PubMed

Double inlet left ventricle (LV) is a type of atrioventricular connection in which the morphologically LV receives more than 50% of the atrioventricular valves when they are separate, or more than 75% of a common atrioventricular valve. The aim of this study was to establish an anatomoechocardiographic correlation between the morphologic features of equivalent anatomic specimens and the echocardiographic images of patients to provide a means of interpreting the image correctly and a more precise diagnosis of the cardiac defect. Echocardiography was used to study 18 patients with LV double inlet who were seen in a congenital heart disease clinic. The morphology of 17 hearts with this malformation from the department of embryology was analyzed to compare the anatomic features with their echocardiographic images. Echocardiography proved to be a noninvasive diagnostic tool that allowed characterization of anatomic and functional aspects of double inlet LV. PMID:15746713

Muñoz-Castellaños, Luis; Espinola-Zavaleta, Nilda; Keirns, Candace

2005-03-01

210

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

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

Inlet-fan flow field computation  

NASA Technical Reports Server (NTRS)

The flow field of a tilt-nacelle inlet-fan combination used for V/STOL aircraft is studied. Under certain flight conditions the inlet is subjected to high angles of attack and/or yaw. This produces a non-uniform or distorted flow field at the fan-face that can lead to large blade stresses. This paper presents an analytical approach to the coupled inlet-fan problem. The nacelle is modelled by a distribution of source panels and the fan by a distribution of radial vortices. A modified actuator disc with losses and a quasi-steady rotor response is used to derive the boundary condition at the fan-face. An example of the calculation is shown.

Matwey, M. D.; Seidel, B. S.; Farrell, C. A., Jr.

1983-01-01

213

Interactive calculation procedures for mixed compression inlets  

NASA Technical Reports Server (NTRS)

The proper design of engine nacelle installations for supersonic aircraft depends on a sophisticated understanding of the interactions between the boundary layers and the bounding external flows. The successful operation of mixed external-internal compression inlets depends significantly on the ability to closely control the operation of the internal compression portion of the inlet. This portion of the inlet is one where compression is achieved by multiple reflection of oblique shock waves and weak compression waves in a converging internal flow passage. However weak these shocks and waves may seem gas-dynamically, they are of sufficient strength to separate a laminar boundary layer and generally even strong enough for separation or incipient separation of the turbulent boundary layers. An understanding was developed of the viscous-inviscid interactions and of the shock wave boundary layer interactions and reflections.

Reshotko, Eli

1983-01-01

214

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

215

Coolant monitoring apparatus for nuclear reactors  

DOEpatents

A system for monitoring coolant conditions within a pressurized vessel. A length of tubing extends outward from the vessel from an open end containing a first line restriction at the location to be monitored. The flowing fluid is cooled and condensed before passing through a second line restriction. Measurement of pressure drop at the second line restriction gives an indication of fluid condition at the first line restriction. Multiple lengths of tubing with open ends at incremental elevations can measure coolant level within the vessel.

Tokarz, Richard D. (West Richland, WA)

1983-01-01

216

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

217

Experimental comparison of carbon-dioxide and liquid nitrogen cryogenic coolants in turning of AISI 1045 steel  

NASA Astrophysics Data System (ADS)

This experimental work is carried out to investigate the performance and influence of cryogenic coolants such as CO2 (carbon dioxide) and LN2 (liquid nitrogen) on cutting temperature, cutting force, tool wear, surface finish and chip morphology in machining of AISI 1045 steel compared to wet machining. The results proved that the application of cryogenic coolants reduced the cutting temperature drastically which resulted in appreciable improvement in surface finish of the product and reduced tool wear. The use of cryogenic LN2 reduced the cutting temperature about 3-17% when compared to CO2 coolant. Application of CO2 reduced the cutting forces and improved the surface finish of the machined part to an extent about 2-12% and 2-14% respectively when compared to the use of cryogenic LN2 coolant. Tool wear was found to be less on the application of CO2 compared to the wet and LN2 machining conditions.

Dilip Jerold, B.; Pradeep Kumar, M.

2012-10-01

218

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

219

NGNP Reactor Coolant Chemistry Control Study  

SciTech Connect

The main focus of this paper is to identify the most desirable ranges of impurity levels in the primary coolant to optimize component life in the primary circuit of the Next Generation Nuclear Plant (NGNP), which will either be a prismatic block or pebble bed reactor.

Brian Castle

2010-11-01

220

The calculation of planar inlet flows  

Microsoft Academic Search

In the case of water jet propulsion units for high-speed vehicles, the inlet represents a system component which has a decisive effect on the quality of the design. The present investigation is concerned with the study of this component on the basis of the assumption of two-dimensional flow, giving attention to considerations of potential theory and the properties of real

C. Carstensen

1983-01-01

221

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...

222

Experimental investigation of a submerged subsonic inlet  

Microsoft Academic Search

The goal of combined computational and experimental study is the design optimization of a generic submerged inlet, which minimizes flow distortion at the engine face. A series of experimental surveys were performed to validate the accompanying computations and to provide additional information regarding the Pareto Set of optimal designs. The objectives of experimental investigation are to: (1) perform comparison between

Vasilije J. Jovanovic

2004-01-01

223

Design and operation considerations for attic inlets  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

224

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....

225

High ethane recovery without inlet COâ removal  

Microsoft Academic Search

The processes discussed in this work have been developed to achieve high levels of ethane recovery from inlet gas streams containing more COâ than can be tolerated by other current processes. These processes can reduce in size or eliminate entirely the COâ treating system required for the ethane recovery facility. The new processes also recover more ethane using less external

J. D. Wilkinson; H. M. Hudson

1982-01-01

226

Icing Characteristics and Anti-Icing Heat Requirements for Hollow and Ternally Modified Gas-Heated Inlet Guide Vanes  

NASA Technical Reports Server (NTRS)

A two-dimensional inlet-guide-vane cascade was investigated to determine the effects of ice formations on the pressure losses across the guide vanes and to evaluate the heated gas flow and temperature required to prevent Icing at various conditions. A gas flow of approximately 0.4 percent of the inlet-air flow was necessary for anti-icing a hollow guide-vane stage at an inlet-gas temperature of 500 F under the following icing conditions: air velocity, 280 miles per hour; water content, 0.9 gram per cubic meter; and Inlet-air static temperature, 00 F. Also presented are the anti-icing gas flows required with modifications of the hollow Internal gas passage, which show heatinput savings greater than 50 percent.

Gray, Vernon H.; Bowden, Dean T.

1950-01-01

227

Cloud-Droplet Ingestion in Engine Inlets with Inlet Velocity Ratios of 1.0 and 0.7  

NASA Technical Reports Server (NTRS)

The paths of cloud droplets into two engine inlets have been calculated for a wide range of meteorological and flight conditions. The amount of water in droplet form ingested by the inlets and the amount and distribution of water impinging on the inlet walls are obtained from these droplet-trajectory calculations. In both types of inlet, a prolate ellipsoid of revolution represents either part or all of the forebody at the center of an annular inlet to an engine. The configurations can also represent a fuselage of an airplane with side ram-scoop inlets. The studies were made at an angle of attack of 0 degree. The principal difference between the two inlets studied is that the inlet-air velocity of one is 0.7 that of the other. The studies of the two velocity ratios lead to some important general concepts of water ingestion in inlets.

Brun, Rinaldo J

1957-01-01

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

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

NASA Technical Reports Server (NTRS)

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

Acker, Loren W; Kleinknecht, Kenneth S

1950-01-01

230

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

231

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2013 CFR

...AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except that—...

2013-01-01

232

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2012 CFR

...AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except that—...

2012-01-01

233

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2011 CFR

...AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except that—...

2011-01-01

234

14 CFR 23.1063 - Coolant tank tests.  

Code of Federal Regulations, 2014 CFR

...AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Liquid Cooling § 23.1063 Coolant tank tests. Each coolant tank must be tested under § 23.965, except that—...

2014-01-01

235

Inlet-engine matching for SCAR including application of a bicone variable geometry inlet  

NASA Technical Reports Server (NTRS)

Airflow characteristics of variable cycle engines (VCE) designed for Mach 2.32 can have transonic airflow requirements as high as 1.6 times the cruise airflow. This is a formidable requirement for conventional, high performance, axisymmetric, translating centerbody mixed compression inlets. An alternate inlet is defined, where the second cone of a two cone center body collapses to the initial cone angle to provide a large off-design airflow capability, and incorporates modest centerbody translation to minimize spillage drag. Estimates of transonic spillage drag are competitive with those of conventional translating centerbody inlets. The inlet's cruise performance exhibits very low bleed requirements with good recovery and high angle of attack capability.

Wasserbauer, J. F.; Gerstenmaier, W. H.

1978-01-01

236

40 CFR 90.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2014 CFR

...exhaust emission compliance over the full range of air inlet filter systems and exhaust muffler systems. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the...

2014-07-01

237

40 CFR 90.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2011 CFR

...exhaust emission compliance over the full range of air inlet filter systems and exhaust muffler systems. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the...

2011-07-01

238

40 CFR 90.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2010 CFR

...exhaust emission compliance over the full range of air inlet filter systems and exhaust muffler systems. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the...

2010-07-01

239

40 CFR 90.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2012 CFR

...exhaust emission compliance over the full range of air inlet filter systems and exhaust muffler systems. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the...

2012-07-01

240

40 CFR 90.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2013 CFR

...exhaust emission compliance over the full range of air inlet filter systems and exhaust muffler systems. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the...

2013-07-01

241

33 CFR 334.1310 - Lutak Inlet, Alaska; restricted areas.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Lutak Inlet, Alaska; restricted areas. 334.1310 Section...REGULATIONS § 334.1310 Lutak Inlet, Alaska; restricted areas. (a) The areas...Army Engineer District, Anchorage, Alaska, and such agencies as he may...

2013-07-01

242

33 CFR 334.1310 - Lutak Inlet, Alaska; restricted areas.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Lutak Inlet, Alaska; restricted areas. 334.1310 Section...REGULATIONS § 334.1310 Lutak Inlet, Alaska; restricted areas. (a) The areas...Army Engineer District, Anchorage, Alaska, and such agencies as he may...

2014-07-01

243

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

244

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.

2011-12-01

245

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

246

Experiments and analysis, by the method of characteristics, on loss of coolant accidents  

Microsoft Academic Search

An outline of a technique for analysis of LOCAs by the method of ; characteristics and some comparisons with experiments are presented. Prediction ; of coolant density in the heated section, pressures, temperatures, and flow rates ; as functions of time following a pipe rupture are discussed. (GE) The Spanish ; Atomic Forum dedicated the 1972 lectures to the problem

S. Banerjee; R. B. Jeffries; H. Goulding; T. Jaganathan

1973-01-01

247

A comparative study of coolant flow optimization on a steel casting machine  

Microsoft Academic Search

In continuous casting of steel a number of parameters have to be set, such as the casting temperature, casting speed and coolant flows that critically affect the safety, quality and productivity of steel production. We have implemented an optimization tool consisting in an optimization algorithm and casting process simulator. The paper describes the process, the optimization task, and the proposed

Bogdan Filipic; T. Robic

2004-01-01

248

Flow in the coolant passages of an internal combustion engine cylinder head  

Microsoft Academic Search

Detailed measurements of the coolant flow field have been made in the water passages of the cylinder head of an internal combustion engine. They were obtained by casting a transparent acrylic model of the cylinder head and using a mixture of hydrocarbon fluids at a predetermined temperature and concentration which ensured that the refractive index of the fluid was identical

C. H. Liu; C. Vafidis; J. H. Whitelaw; R. Margary

1990-01-01

249

A Comparative Study of Coolant Flow Optimization on a Steel Casting Machine  

Microsoft Academic Search

In continuous casting of steel a number of param- eters have to be set, such as the casting temperature, casting speed and coolant flows, that critically affect the safety, quality and productivity of steel production. We have implemented an optimization tool consisting of an optimization algorithm and a casting process simulator. The paper describes the process, the optimization task, and

Bogdan Filipi; Tea Robic

250

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

251

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

252

Flow-Control Devices For Inlets Of Indraft Wind Tunnels  

NASA Technical Reports Server (NTRS)

Report presents theoretical and experimental study of effects of antiturbulence flow-control devices in inlet of indraft wind tunnel upon nonuniformity of flow in test section of tunnel. Flow-control devices in question include vanes, screens, and honeycombs, placed in inlet upstream of contracting section of tunnel leading from inlet to test section.

Ross, James C.

1992-01-01

253

Performance of Air Inlets at Transonic and Low Supersonic Speeds  

NASA Technical Reports Server (NTRS)

A general discussion of the air-inlet problem is presented. Recently obtained drag and pressure-recovery data for transonic-type nose, scoop, and wing-root inlets are summarized. Preliminary results concerning the performance of the sharp-edged supersonic-type inlets at transonic and subsonic speeds also are given.

Nichols, Mark R; Pendley, Robert E

1952-01-01

254

Case Study: Promoting the Stability of the bidos Lagoon Inlet  

E-print Network

Case Study: Promoting the Stability of the �bidos Lagoon Inlet André B. Fortunato1 and Anabela Oliveira2 Abstract: The stabilization of tidal inlets by jetties interrupts the littoral drift and has inlet the �bidos Lagoon, Portugal and minimize maintenance dredging, while avoiding the disadvantages

255

Influence of Inlet Duct Layouts on Cyclone Performance  

Microsoft Academic Search

It is common in a large capacity circulating fluidized bed (CFB) boiler to adopt several cyclones in parallel to the furnace. The lengths of the inlet ducts of the cyclones are very short due to CFB boilers design. Different inlet ducts layouts affect the cyclones performance. Based on cold experiments and numerical simulation, the effects of inlet duct layouts (inner-side

LI Zhan-guo; LIU Zhi-cheng; HE Jun; NA Yong-jie; LÜ Qing-gang

256

Optimal design of storm water inlets for highway drainage  

Microsoft Academic Search

A new methodology and computational model are developed for direct evaluation of an optimal storm water inlet design. The optimal design is defined as the least-cost combination of inlet types, sizes and locations that effectively drain a length of pavement. Costs associated with inlets are user-defined and can include those associated with materials, installation and maintenance, as well as other

John W. Nicklow; Anders P. Hellman

2004-01-01

257

CFD simulation and experimental validation of a GM type double inlet pulse tube refrigerator  

Microsoft Academic Search

Pulse tube refrigerator has the advantages of long life and low vibration over the conventional cryocoolers, such as GM and stirling coolers because of the absence of moving parts in low temperature. This paper performs a three-dimensional computational fluid dynamic (CFD) simulation of a GM type double inlet pulse tube refrigerator (DIPTR) vertically aligned, operating under a variety of thermal

Y. P. Banjare; R. K. Sahoo; S. K. Sarangi

2010-01-01

258

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

Microsoft Academic Search

Gas turbine air cooling systems serve to raise performance to peak power levels during the hot months when high atmospheric temperatures cause reductions in net power output. This work describes the technical and economic advantages of providing a compressor inlet air cooling system to increase the gas turbine's power rating and reduce its heat rate. The pros and cons of

M. Delucia; R. Bronconi; E. Carnevale

1994-01-01

259

The role of jet inlet geometry in impinging jet heat transfer, modeling and experiments  

Microsoft Academic Search

Effects of jet inlet geometry and aspect ratio on local and average heat transfer characteristics of totally nine confined impinging jets have been investigated experimentally using thermochromic liquid crystals and numerically by using a 3-D low Reynolds number k–? model. Experimental study by using liquid crystals for temperature measurement was conducted for three different jet exit geometries (circular, elliptic, rectangular).

M. F. Koseoglu; S. Baskaya

2010-01-01

260

Optimal Design of a Subsonic Submerged Inlet  

NASA Astrophysics Data System (ADS)

A multi-objective optimization study based on an epsilon-constraint method is conducted for the design optimization of a subsonic submerged air vehicle inlet. The multi-objective optimization problem is reformulated by minimizing one of the objectives and restricting the other objectives within user specified values. The figures of merits are the engine-face distortion and swirl that determines the inlet/engine compatibility. The distortion index is minimized while the feasible design space is determined by the swirl index. The design variables are the geometrical parameters defining the surface alteration. The design algorithm is driven by a gradient-based optimizer, and is constructed by integrating the optimizer with a solid modeller (Pro/Engineer), a mesh generator (Grid/Pro) and a flow solver (GASPex). The optimizer is CFSQP (C code for Feasible Sequential Quadratic Programming). Integration of the software packages is achieved by a Perl script. In order to verify the numerical results, an experimental setup for the same inlet geometry is prepared to run at the same flow conditions. The presentation will describe the numerical approach and summarize the results.

Taskinoglu, Ezgi; Jovanovic, Vasilije; Elliott, Gregory; Knight, Doyle

2003-11-01

261

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

262

Preliminary analysis of loss-of-coolant accident in Fukushima nuclear accident  

NASA Astrophysics Data System (ADS)

Loss-of-Coolant Accident (LOCA) in Boiling Water Reactor (BWR) especially on Fukushima Nuclear Accident will be discussed in this paper. The Tohoku earthquake triggered the shutdown of nuclear power reactors at Fukushima Nuclear Power station. Though shutdown process has been completely performed, cooling process, at much smaller level than in normal operation, is needed to remove decay heat from the reactor core until the reactor reach cold-shutdown condition. If LOCA happen at this condition, it will cause the increase of reactor fuel and other core temperatures and can lead to reactor core meltdown and exposure of radioactive material to the environment such as in the Fukushima Dai Ichi nuclear accident case. In this study numerical simulation has been performed to calculate pressure composition, water level and temperature distribution on reactor during this accident. There are two coolant regulating system that operational on reactor unit 1 at this accident, Isolation Condensers (IC) system and Safety Relief Valves (SRV) system. Average mass flow of steam to the IC system in this event is 10 kg/s and could keep reactor core from uncovered about 3,2 hours and fully uncovered in 4,7 hours later. There are two coolant regulating system at operational on reactor unit 2, Reactor Core Isolation Condenser (RCIC) System and Safety Relief Valves (SRV). Average mass flow of coolant that correspond this event is 20 kg/s and could keep reactor core from uncovered about 73 hours and fully uncovered in 75 hours later. There are three coolant regulating system at operational on reactor unit 3, Reactor Core Isolation Condenser (RCIC) system, High Pressure Coolant Injection (HPCI) system and Safety Relief Valves (SRV). Average mass flow of water that correspond this event is 15 kg/s and could keep reactor core from uncovered about 37 hours and fully uncovered in 40 hours later.

Su'ud, Zaki; Anshari, Rio

2012-06-01

263

Preliminary analysis of loss-of-coolant accident in Fukushima nuclear accident  

SciTech Connect

Loss-of-Coolant Accident (LOCA) in Boiling Water Reactor (BWR) especially on Fukushima Nuclear Accident will be discussed in this paper. The Tohoku earthquake triggered the shutdown of nuclear power reactors at Fukushima Nuclear Power station. Though shutdown process has been completely performed, cooling process, at much smaller level than in normal operation, is needed to remove decay heat from the reactor core until the reactor reach cold-shutdown condition. If LOCA happen at this condition, it will cause the increase of reactor fuel and other core temperatures and can lead to reactor core meltdown and exposure of radioactive material to the environment such as in the Fukushima Dai Ichi nuclear accident case. In this study numerical simulation has been performed to calculate pressure composition, water level and temperature distribution on reactor during this accident. There are two coolant regulating system that operational on reactor unit 1 at this accident, Isolation Condensers (IC) system and Safety Relief Valves (SRV) system. Average mass flow of steam to the IC system in this event is 10 kg/s and could keep reactor core from uncovered about 3,2 hours and fully uncovered in 4,7 hours later. There are two coolant regulating system at operational on reactor unit 2, Reactor Core Isolation Condenser (RCIC) System and Safety Relief Valves (SRV). Average mass flow of coolant that correspond this event is 20 kg/s and could keep reactor core from uncovered about 73 hours and fully uncovered in 75 hours later. There are three coolant regulating system at operational on reactor unit 3, Reactor Core Isolation Condenser (RCIC) system, High Pressure Coolant Injection (HPCI) system and Safety Relief Valves (SRV). Average mass flow of water that correspond this event is 15 kg/s and could keep reactor core from uncovered about 37 hours and fully uncovered in 40 hours later.

Su'ud, Zaki; Anshari, Rio [Nuclear and Biophysics Research Group, Dept. of Physics, Bandung Institute of Technology, Jl.Ganesha 10, Bandung, 40132 (Indonesia)

2012-06-06

264

A comparative assessment of alternative combustion turbine inlet air cooling system  

SciTech Connect

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

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

1996-02-01

265

Inlet Turbulence and Length Scale Measurements in a Large Scale Transonic Turbine Cascade  

NASA Technical Reports Server (NTRS)

Constant temperature hotwire anemometry data were acquired to determine the inlet turbulence conditions of a transonic turbine blade linear cascade. Flow conditions and angles were investigated that corresponded to the take-off and cruise conditions of the Variable Speed Power Turbine (VSPT) project and to an Energy Efficient Engine (EEE) scaled rotor blade tip section. Mean and turbulent flowfield measurements including intensity, length scale, turbulence decay, and power spectra were determined for high and low turbulence intensity flows at various Reynolds numbers and spanwise locations. The experimental data will be useful for establishing the inlet boundary conditions needed to validate turbulence models in CFD codes.

Thurman, Douglas; Flegel, Ashlie; Giel, Paul

2014-01-01

266

Results of analyzing accidents with core meltdown in fast reactors with sodium as the coolant  

Microsoft Academic Search

cross section is completely blocked at the inlet. The sodium temperature reaches the saturation point first in the center of the core's height about 0.5 sec after the time of blocking and the zone of boiling extends upward and downward thereafter. Evaporation of the liquid sodium film in the center lasts 0.3 sec. Evaporation begins in the upper core portion

G. B. Usynin; G. N. Vlasichev; Yu. I. Anoshkin; M. A. Semenychev; S. V. Boldin

1992-01-01

267

Fortnightly tides and subtidal motions in a choked inlet  

NASA Astrophysics Data System (ADS)

Amplitudes of semi-diurnal tidal fluctuations measured at an ocean inlet system decay nearly linearly by 87% between the ocean edge of the offshore ebb-tidal delta and the backbay. A monochromatic, dynamical model for a tidally choked inlet separately reproduces the evolution of the amplitudes and phases of the semi-diurnal and diurnal tidal constituents observed between the ocean and inland locations. However, the monochromatic model over-predicts the amplitude and under-predicts the lag of the lower-frequency subtidal and fortnightly motions observed in the backbay. A dimensional model that considers all tidal constituents simultaneously, balances the along-channel pressure gradient with quadratic bottom friction, and that includes a time-varying channel water depth, is used to show that that these model-data differences are associated with nonlinear interactions between the tidal constituents that are not included in non-dimensional, monochromatic models. In particular, numerical simulations suggest that the nonlinear interactions induced by quadratic bottom friction modify the amplitude and phase of the subtidal and fortnightly backbay response. This nonlinear effect on the low-frequency (subtidal and fortnightly) motions increases with increasing high-frequency (semi-diurnal) amplitude. The subtidal and fortnightly motions influence water exchange processes, and thus backbay temperature and salinity.

MacMahan, Jamie; van de Kreeke, Jacobus; Reniers, Ad; Elgar, Steve; Raubenheimer, Britt; Thornton, Ed; Weltmer, Micah; Rynne, Patrick; Brown, Jenna

2014-10-01

268

Use of Internal Coolant as a Means of Permitting Increase in Engine Take-Off Power  

NASA Technical Reports Server (NTRS)

Engine tests, together with estimates made at Langley Memorial Aeronautical Laboratory, indicate that a 25-percent increase in take-off power can be obtained with present-day aircraft engines without increasing either the knock limit of the fuel or the external cooling requirements of the engine. This increase in power with present fuels and present external cooling is made possible through the use of an internal coolant inducted through the inlet manifold. Estimates on aircraft indicate that this 25-percent increase in power will permit an approximate usable increase of 8.5 percent in the take-off load of existing military airplanes. This increase in load is equivalent to an increase in the weight of gasoline normally carried of between 30 and 65 percent.

Rothrock, Addison M

1944-01-01

269

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

270

TACT 1: A computer program for the transient thermal analysis of a cooled turbine blade or vane equipped with a coolant insert. 2. Programmers manual  

NASA Technical Reports Server (NTRS)

A computer program to calculate transient and steady state temperatures, pressures, and coolant flows in a cooled axial flow turbine blade or vane with an impingement insert is described. Coolant-side heat transfer coefficients are calculated internally in the program, with the user specifying either impingement or convection heat transfer at each internal flow station. Spent impingement air flows in a chordwise direction and is discharged through the trailing edge and through film cooling holes. The ability of the program to handle film cooling is limited by the internal flow model. Input to the program includes a description of the blade geometry, coolant-supply conditions, outside thermal boundary conditions, and wheel speed. The blade wall can have two layers of different materials, such as a ceramic thermal barrier coating over a metallic substrate. Program output includes the temperature at each node, the coolant pressures and flow rates, and the coolant-side heat transfer coefficients.

Gaugler, R. E.

1979-01-01

271

Aerodynamic performance of 0.4066-scale model of JT8D refan stage with S-duct inlet  

NASA Technical Reports Server (NTRS)

A scale model of the JT8D refan stage was tested with a scale model of the S-duct inlet design for the refanned Boeing 727 center engine. Detailed survey data of pressures, temperatures, and flow angles were obtained over a range of flows at speeds from 70 to 97 percent of design speed. Two S-duct configurations were tested; one with a bellmouth inlet and the other with a flight lip inlet. The results indicated that the overall performance was essentially unaffected by the distortion generated by the S-duct inlet. The stall weight flow increased by less than 0.5 kg/sec (approximately 1.5% of design flow) with the S-duct inlet compared with that obtained with uniform flow. The detailed measurements indicated that the inlet guide vane (IGV) significantly reduced circumferential variations. For example, the flow angles ahead of the IGV were positive in the right half of the inlet and negative in the left half. Behind the IGV, the flow angles tended to be more uniform circumferentially.

Moore, R. D.; Kovich, G.; Lewis, G. W., Jr.

1977-01-01

272

Effect of steady-state pressure distortion on inlet flow to a high-bypass-ratio turbofan engine  

NASA Technical Reports Server (NTRS)

Static pressure and total pressure distributions were measured in the inlet duct upstream of the engine inlet and within the fan and compressor of a YTF34 turbofan engine. In addition, the free stream flow angle was measured between the distortion generator and the engine inlet. Distortions were generated using three screen configurations with extents of 90 deg or 180 deg. The screens were mounted on a rotatable screen assembly. Reynolds number index upstream of the distortion device was maintained at 0.5 or 0.2, and engine fan speed corrected to station 2 temperature was maintained at 80 or 90 percent of rated condition (7005 rpm). Flow angle was nearly constant near the distortion device and increased as flow approached the engine inlet. The largest flow angle occurred in the hub region of the engine inlet. Static pressure distortion along the inlet duct increased exponentially as the flow approached the engine. Both static pressure and total pressure distortions were attenuated between engine inlet and compressor exit.

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

1982-01-01

273

Morphological evolution of an ephemeral tidal inlet from opening to closure: The Albufeira inlet, Portugal  

NASA Astrophysics Data System (ADS)

Like other similar coastal systems, the Albufeira lagoon is artificially opened every year to promote water renewal and closes naturally within a few months. The evolution of the Albufeira Lagoon Inlet from its opening in April 2010 to its closure 8 months later is qualitatively and quantitatively analyzed through a combination of monthly field surveys and the application of a process-based morphodynamic model. Field data alone would not cover the whole space-time domain of the morphology of the inlet during its life time, whereas the morphodynamic model alone cannot reliably simulate the morphological development. Using a nudging technique introduced herein, this problem is overcome and a reliable and complete data set is generated for describing the morphological development of the tidal inlet. The new technique is shown to be a good alternative to extensive model calibration, as it can drastically improve the model performance. Results reveal that the lagoon imported sediments during its life span. However, the whole system (lagoon plus littoral barrier) actually lost sediments to the sea. This behavior is partly attributed to the modulation of tidal asymmetry by the spring-neap cycle, which reduces flood dominance on spring tides. Results also allowed the assessment of the relationship between the spring tidal prism and the cross-section of tidal inlets (the PA relationship). While this relationship is well established from empirical, theoretical and numerical evidences, its validity in inlets that are small or away from equilibrium was unclear. Results for the Albufeira lagoon reveal an excellent match between the new data and the empirical PA relationship derived for larger inlets and equilibrium conditions, supporting the validity of the relationship beyond its original scope.

Fortunato, André B.; Nahon, Alphonse; Dodet, Guillaume; Rita Pires, Ana; Conceição Freitas, Maria; Bruneau, Nicolas; Azevedo, Alberto; Bertin, Xavier; Benevides, Pedro; Andrade, César; Oliveira, Anabela

2014-02-01

274

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

275

Microstructural characterization of primary coolant pipe steel  

SciTech Connect

Atom probe field-ion microscopy, analytical electron microscopy, and optical microscopy have been used to investigate the changes that occur in the microstructure of cast CF 8 primary coolant pipe stainless steel after long term thermal aging. The cast duplex microstructure consisted of austenite with 15% delta-ferrite. Investigation of the aged material revealed that the ferrite spinodally decomposed into a fine scaled network of ..cap alpha.. and ..cap alpha..'. A fine G-phase precipitate was also observed in the ferrite. The observed degradation in mechanical properties is probably a consequence of the spinodal decomposition in the ferrite.

Miller, M.K.; Bentley, J.

1986-01-01

276

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

277

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

278

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

279

Study of Ram-air Heat Exchangers for Reducing Turbine Cooling-air Temperature of a Supersonic Aircraft Turbojet Engine  

NASA Technical Reports Server (NTRS)

The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude of 70,000 feet. A compressor-bleed-air weight flow of 2.7 pounds per second was assumed for the coolant; ram air was considered as the other fluid. Pressure drops and inlet states of both fluids were prescribed, and ranges of compressor-bleed-air temperature reductions and of the ratio of compressor-bleed to ram-air weight flows were considered.

Diaguila, Anthony J; Livingood, John N B; Eckert, Ernst R G

1956-01-01

280

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

281

Secondary flow and heat transfer control in gas turbine inlet nozzle guide vanes  

NASA Astrophysics Data System (ADS)

Endwall heat transfer is a very serious problem in the inlet nozzle guide vane region of gas turbine engines. To resolve heat transfer concerns and provide the desired thermal protection, modern cooling flows for the vane endwalls tend to be excessive leading to lossy and inefficient designs. Coolant introduction is further complicated by the flow patterns along vane endwall surfaces. They are three-dimensional and dominated by strong, complex secondary flows. To achieve performance goals for next-generation engines, more aerodynamically efficient and advanced cooling concepts, including combustor bleed cooling, must be investigated. To this end, the overall performance characteristics of several combustor bleed flow designs are assessed in this experimental study. In particular, their contributions toward secondary flow control and component cooling are documented. Testing is performed in a large-scale, guide vane simulator comprised of three airfoils encased between one contoured and one flat endwall. Core flow is supplied to this simulator at an inlet chord Reynolds number of 350,000 and turbulence intensity of 9.5%. Combustor bleed cooling flow is injected through the contoured endwall via inclined slots. The slots vary in cross-sectional area, have equivalent slot widths, and are positioned with their leeward edges 10% of the axial chord ahead of the airfoil leading edges. Measurements with hot-wire anemometry characterize the inlet and exit flow fields of the cascade. Total and static pressure measurements document aerodynamic performance. Thermocouple measurements detail thermal fields and permit evaluation of surface adiabatic effectiveness. To elucidate the effects of bleed injection, data are compared to an experiment taken without bleed. The influence of bleed mass flow rate and slot geometry on the aerodynamic losses and thermal protection arc given. This study suggests that such combustor bleed flow cooling offers significant thermal protection without imposing aerodynamic penalties. Such performance is contrary to the performance of present vane cooling schemes. The results of this investigation support designs which incorporate combustor coolant injection upstream of the airfoil leading edges. To complement, a short exploratory study regarding the effects of surface roughness was also performed. Results indicate modified cooling performance and significantly higher aerodynamic losses with rough surfaces.

Burd, Steven Wayne

1998-12-01

282

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. PMID:22262808

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

2012-01-01

283

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

284

Influence of Inlet Air Temperature on Gasoline HCCI Particulate Emissions  

Microsoft Academic Search

Particulate emissions from homogeneous charge compression ignition (HCCI) engines have been usually considered negligible, and the measurement of particulates (PM) with HCCI combustion systems has been extremely rare. A report from Ford and the authors' own recently published work suggest that PM emissions from gasoline HCCI engines should not be neglected. It has been shown that PM emissions for SI

Jacek Misztal; Hongming Xu; Athanasios Tsolakis; Miroslaw L. Wyszynski; George Constandinides; Philip Price; Jun Qiao

2009-01-01

285

Active Flow Control on an Aggressive Serpentine Duct Inlet  

NASA Astrophysics Data System (ADS)

For military applications, inlet designs are constrained by low observability requirements, which call for the use of a serpentine 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 utilizing active flow control to mitigate separation in a highly aggressive serpentine duct (L/D=1.5), at Mach numbers up to 0.45, were conducted. Specifically, steady and unsteady flow control techniques were compared by measuring the static pressures along the inlet walls, the pressure recovery and distortion at the AIP, and the velocity field inside the duct using Particle Image Velocimetry. Through these experiments a better understanding of the highly three dimensional flow interactions was formulated.

Vaccaro, John; Amitay, Michael

2008-11-01

286

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

287

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

288

Computational effects of inlet representation on powered hypersonic, airbreathing models  

NASA Technical Reports Server (NTRS)

Computational results are presented to illustrate the powered aftbody effects of representing the scramjet inlet on a generic hypersonic vehicle with a fairing, to divert the external flow, as compared to an operating flow-through scramjet inlet. This study is pertinent to the ground testing of hypersonic, airbreathing models employing scramjet exhaust flow simulation in typical small-scale hypersonic wind tunnels. The comparison of aftbody effects due to inlet representation is well-suited for computational study, since small model size typically precludes the ability to ingest flow into the inlet and perform exhaust simulation at the same time. Two-dimensional analysis indicates that, although flowfield differences exist for the two types of inlet representations, little, if any, difference in surface aftbody characteristics is caused by fairing over the inlet.

Huebner, Lawrence D.; Tatum, Kenneth E.

1993-01-01

289

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

290

Analysis of Loss-of-Coolant Accidents in the NBSR  

SciTech Connect

This report documents calculations of the fuel cladding temperature during loss-of-coolant accidents in the NBSR. The probability of a pipe failure is small and procedures exist to minimize the loss of water and assure emergency cooling water flows into the reactor core during such an event. Analysis in the past has shown that the emergency cooling water would provide adequate cooling if the water filled the flow channels within the fuel elements. The present analysis is to determine if there is adequate cooling if the water drains from the flow channels. Based on photographs of how the emergency water flows into the fuel elements from the distribution pan, it can be assumed that this water does not distribute uniformly across the flow channels but rather results in a liquid film flowing downward on the inside of one of the side plates in each fuel element and only wets the edges of the fuel plates. An analysis of guillotine breaks shows the cladding temperature remains below the blister temperature in fuel plates in the upper section of the fuel element. In the lower section, the fuel plates are also cooled by water outside the element that is present due to the hold-up pan and temperatures are lower than in the upper section. For small breaks, the simulation results show that the fuel elements are always cooled on the outside even in the upper section and the cladding temperature cannot be higher than the blister temperature. The above results are predicated on assumptions that are examined in the study to see their influence on fuel temperature.

Baek J. S.; Cheng L.; Diamond, D.

2014-05-23

291

8. View southwest at the northeastern end of culvert inlet, ...  

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

8. View southwest at the northeastern end of culvert inlet, with canal bank completely removed. Left to right: back of curved wingwall; tops of high inlet barrels; vertical transition wall between high inlet barrels and low interior barrels; tops of low, interior barrels; vertical heartening planks at former canal edge of canal bank. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

292

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

293

Kinematic wave method for determination of road drainage inlet spacing  

NASA Astrophysics Data System (ADS)

Based on the kinematic wave theory, which is shown to be generally applicable to road drainage situations, a method has been developed for the determination of road drainage inlet spacing under the continuous grade condition. The input data required are the allowable maximum flood width, the physical characteristics of the roadway, the empirical relationship between the maximum discharge and the intercepted flow, and the rainfall intensity—duration curve. Application of the method to the Singapore inlet condition shows that for a given maximum flood width, the inlet spacing varies with the cross and longitudinal slopes of the roadway. The spacing of inlets is wider for roads with steeper slopes.

Wong, Tommy S. W.

294

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

295

Parametric study on maximum transportable distance and cost for thermal energy transportation using various coolants  

SciTech Connect

The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors and thermal energy from advanced nuclear reactor can be used for various purposes such as district heating, desalination, hydrogen production and other process heat applications, etc. The process heat industry/facilities will be located outside the nuclear island due to safety measures. This thermal energy from the reactor has to be transported a fair distance. In this study, analytical analysis was conducted to identify the maximum distance that thermal energy could be transported using various coolants such as molten-salts, helium and water by varying the pipe diameter and mass flow rate. The cost required to transport each coolant was also analyzed. The coolants analyzed are molten salts (such as: KClMgCl2, LiF-NaF-KF (FLiNaK) and KF-ZrF4), helium and water. Fluoride salts are superior because of better heat transport characteristics but chloride salts are most economical for higher temperature transportation purposes. For lower temperature water is a possible alternative when compared with He, because low pressure He requires higher pumping power which makes the process very inefficient and economically not viable for both low and high temperature application.

Su-Jong Yoon; Piyush Sabharwall

2014-07-01

296

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

297

Acoustic Environment of Admiralty Inlet: Broadband Noise Measurements  

SciTech Connect

Admiralty Inlet has been selected as a potential tidal energy site. It is located near shipping lanes, is a highly variable acoustic environment, and is frequented by the highly endangered southern resident killer whale (SRKW). Resolving environmental impacts is the first step to receiving approval to deploy tidal turbines at Admiralty Inlet. Of particular concern is the potential for blade strike or other negative interactions between the SRKW and the tidal turbine. A variety of technologies including passive and active monitoring systems are being considered as potential tools to determine the presence of SRKW in the vicinity of the turbines. Broadband noise level measurements are critical for the determination of design and operation specifications of all marine and hydrokinetic energy capture technologies. Acoustic environment data at the proposed site was acquired at different depths using a cabled vertical line array (VLA) with four calibrated hydrophones. The sound pressure level (SPL) power spectrum density was estimated based on the fast Fourier transform. This study describes the first broadband SPL measurements for this site at different depths with frequency ranging from 10 kHz to 480 kHz in combination with other information. To understand the SPL caused by this bedload transport, three different pressure sensors with temperature and conductivity were also assembled on the VLA to measure the conditions at the hydrophone deployment depth. The broadband SPL levels at frequency ranges of 3 kHz to 7 kHz as a function of depth were estimated. Only the hydrophone at an average depth of 40 m showed the strong dependence of SPL with distance from the bottom, which was possibly caused by the cobbles shifting on the seabed. Automatic Identification System data were also studied to understand the SPL measurements.

Xu, Jinshan; Deng, Zhiqun; Martinez, Jayson J.; Carlson, Thomas J.; Myers, Joshua R.; Weiland, Mark A.; Jones, Mark E.

2011-09-30

298

Inlet distortion in engines on VSTOL aircraft  

NASA Technical Reports Server (NTRS)

This report presents the results of a research program on inlet distortion in engines on VSTOL aircraft carried out at the MIT Gas Turbine Laboratory during the period Oct. 1989 - Dec. 1993. The program focused on the development of three dimensional flow computational methodology for predicting the effects of nonuniform flow on the performance of aircraft engines in VSTOL aircraft, the development of a three dimensional instability analysis of flow in multistage axial compressors, and the preliminary applications of these newly developed methodologies for elucidating the effects of flow three dimensionality. The accomplishments of the program are brought out when the current status of predictive capabilities for three dimensional flow instabilities in compressors is assessed against that in 1989.

Tan, Choon S.; Greitzer, Edward M.

1994-01-01

299

Power module assemblies with staggered coolant channels  

DOEpatents

A manifold is provided for supporting a power module assembly with a plurality of power modules. The manifold includes a first manifold section. The first face of the first manifold section is configured to receive the first power module, and the second face of the first manifold section defines a first cavity with a first baseplate thermally coupled to the first power module. The first face of the second manifold section is configured to receive the second power module, and the second face of the second manifold section defines a second cavity with a second baseplate thermally coupled to the second power module. The second face of the first manifold section and the second face of the second manifold section are coupled together such that the first cavity and the second cavity form a coolant channel. The first cavity is at least partially staggered with respect to second cavity.

Herron, Nicholas Hayden; Mann, Brooks S; Korich, Mark D

2013-07-16

300

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

SciTech Connect

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% 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% 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% when compared to larger gas turbines.

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

1992-12-01

301

Prediction of film cooling with a liquid coolant  

Microsoft Academic Search

A numerical method of analyzing film cooling with a liquid coolant is presented. The model assumes a turbulent boundary-layer flow for the hot gas stream and a Couette flow in the liquid coolant film. A marching procedure is employed for solution of the equations of mass, momentum, enthalpy and species conservation. Numerical results for an air-water system are presented. The

T. R. Shembharkar; B. R. Pai

1986-01-01

302

CATALYTIC HYDROCRACKING OF HIGH BOILER IN NUCLEAR REACTOR COOLANT  

Microsoft Academic Search

Selective hydrocracking of total coolant was found to be an efficient ; and economic method for reconstitution of high boiler in the coolant to usable ; product. Such a process could eliminate the expense of vacuum distillation and ; disposal of high boilers produced in a nuclear reactor power plant. The ; selective conversion was possible since polyphenyls were found

1963-01-01

303

The IRIS Spool-Type Reactor Coolant Pump  

Microsoft Academic Search

IRIS (International Reactor Innovative and Secure) is a light water cooled, 335 MWe power reactor which is being designed by an international consortium as part of the US DOE NERI Program. IRIS features an integral reactor vessel that contains all the major reactor coolant system components including the reactor core, the coolant pumps, the steam generators and the pressurizer. This

J. M. Kujawski; D. M. Kitch; L. E. Conway

2002-01-01

304

Development and performance of a large-scale, transonic turbine blade cascade facility for aerodynamic studies of merging coolant-mainstream flows  

NASA Astrophysics Data System (ADS)

A new, large scale, linear cascade facility of turbine blades has been developed for the experimental exploration of the aerodynamic aspects of film cooling technology. Primary interest is in the mixing of the ejected coolant with the mainstream, at both subsonic and supersonic mainstream Mach numbers at the cascade exit. In order to achieve a spatial resolution adequate for the exploration of details on the scale of the coolant ejection holes, the cascade dimensions were maximized, within the limitations of the air supply system. The cascade contains four blades (three passages) with 14.05 cm axial chord, 17.56 cm span and a design total turning angle of 130.6 degrees. Exit Mach numbers range from 0.6 to 1.5 and Reynolds numbers from 0.5 to 1.5 million. The air supply system capacity allows run times up to five minutes at maximum flow rates. A coolant supply system has been built to deliver mixtures of SFsb6 and air to simulate coolant/mainstream density ratios up to 2. The cascade contains several novel features. A full-perimeter bleed slot upstream of the blades is used to remove the approach boundary layer from all four walls, to improve the degree of two-dimensionality. The exit flow is bounded by two adjustable tailboards that are hinged at the trailing edges and actuated to set the exit flow direction according to the imposed pressure ratio. The boards are perforated and subjected to mass removal near the blades, to minimize the undesirable reflection of shocks and expansion waves. A probe actuator is incorporated that allows continuous positioning of probes in the exhaust stream, in both the streamwise and pitchwise directions. Diagnostic methods include extensive surface pressure taps on the approach and exhaust ducts and on the blade surfaces. The large size permitted as many as 19 taps on the trailing edge itself. Shadowgraph and schlieren are available. A three-prong wake probe has been constructed to simultaneously measure total and static pressures, flow direction, total temperature and heavy gas concentration. Initial data are presented to demonstrate the range of the attainable operating parameters. The facility contains a number of adjustable components: the effects of these adjustments has been explored on pressure (Mach number) distributions in the approach duct, the exhaust duct and on the blades themselves. Boundary layer profiles have been determined in the approach duct for different inlet Mach numbers. The approach flow was affected by adjustments of the bleed system configuration. Shadowgraphs (still photos and video tapes) were taken that show clean, well-defined blade trailing edge shock patterns conforming to expectations. Good periodicity was demonstrated at subsonic speeds. At supersonic speeds the suction surface Mach number distributions, near the trailing edges, were found to be very sensitive to the angular setting and porosity of the nearby tailboard. The porous tailboards were effective in attenuating reflections of shocks incident on them. Solid tailboards (obtained by covering the perforated surface with tape) produced bifurcated Mach reflections. (Abstract shortened by UMI.)

Al-Sayeh, Amjad Isaaf

1998-11-01

305

Realistic Small and Intermediate-Break Loss-of-Coolant Accident Analysis Using WCOBRA\\/TRAC  

Microsoft Academic Search

Since the 1988 Appendix K Rulemaking change, there has been significant interest in the development of codes and methodologies for 'best-estimate' analysis of loss-of-coolant accidents (LOCAs). Most development has been directed toward large-break (LB) LOCAs (LBLOCAs), since for most pressurized water reactors (PWRs), the LBLOCA generates the limiting peak cladding temperature (PCT). As plants age, are uprated, and continue to

Stephen M. Bajorek; Nikolay Petkov; Katsuhiro Ohkawa; Robert M. Kemper; Arthur P. Ginsberg

2001-01-01

306

A thermoelectric generation waste heat recovery system using engine coolant for light-duty ICE vehicles  

Microsoft Academic Search

We have proposed and developed a low temperature thermoelectric generator using engine water coolant of light-duty vehicles. Experimental results from test vehicle, of which engine size is about 2.0 liters, show that fabricated prototype Thermoelectric Generator generates more than 75W for driving condition of 80 km\\/hour, and output power is about 28Watt during idle condition. The proposed TEG can replace

Jungho Yoo; Shiho Kim

2010-01-01

307

Methods for incorporating the effects of LWR coolant environments in pressure vessel and piping fatigue evaluations  

Microsoft Academic Search

This paper summarizes the work performed at Argonne National Laboratory on the fatigue of piping and pressure vessel steels in the coolant environments of light water reactors. The existing fatigue strain vs. life ({var_epsilon}-N) data were evaluated to establish the effects of various material and loading variables, such as steel type, strain range, strain rate, temperature, and dissolved-oxygen level in

O. K. Chopra; W. J. Shack

2002-01-01

308

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

309

LAKE WORTH INLET (PALM BEACH HARBOR) NAVIGATION IMPROVEMENT PROJECT  

E-print Network

LAKE WORTH INLET (PALM BEACH HARBOR) NAVIGATION IMPROVEMENT PROJECT PALM BEACH COUNTY, FLORIDA 24 January 2014 ABSTRACT: Lake Worth Inlet connects Palm Beach Harbor to the Atlantic Ocean. The port is located in Riviera Beach, Palm Beach County, Florida. The Port of Palm Beach is the fourth busiest

US Army Corps of Engineers

310

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.  

Code of Federal Regulations, 2014 CFR

...48? North, longitude 122°37?23? West on the north shore of Sinclair Inlet; and latitude 47°32?52? North...122°39?07? West (Point G); thence west to the north shore of Sinclair Inlet at latitude 47°33?04.11?...

2014-07-01

311

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.  

Code of Federal Regulations, 2011 CFR

...48? North, longitude 122°37?23? West on the north shore of Sinclair Inlet; and latitude 47°32?52? North...122°39?07? West (Point G); thence west to the north shore of Sinclair Inlet at latitude 47°33?04.11?...

2011-07-01

312

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.  

Code of Federal Regulations, 2012 CFR

...48? North, longitude 122°37?23? West on the north shore of Sinclair Inlet; and latitude 47°32?52? North...122°39?07? West (Point G); thence west to the north shore of Sinclair Inlet at latitude 47°33?04.11?...

2012-07-01

313

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.  

Code of Federal Regulations, 2010 CFR

...48? North, longitude 122°37?23? West on the north shore of Sinclair Inlet; and latitude 47°32?52? North...122°39?07? West (Point G); thence west to the north shore of Sinclair Inlet at latitude 47°33?04.11?...

2010-07-01

314

33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.  

Code of Federal Regulations, 2013 CFR

...48? North, longitude 122°37?23? West on the north shore of Sinclair Inlet; and latitude 47°32?52? North...122°39?07? West (Point G); thence west to the north shore of Sinclair Inlet at latitude 47°33?04.11?...

2013-07-01

315

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

316

Boundary layer ingesting inlet design for a silent aircraft  

E-print Network

(cont.) common nacelle, L/D ratios between 2.5 and 3.0, fan face to throat area ratios above 1.06, and offsets lower than 11%. Curvature ahead of the inlet should be avoided as well as bifurcations inside the duct. Inlet ...

Freuler, Patrick N., 1980-

2005-01-01

317

Isolated testing of highly maneuverable inlet con cepts  

NASA Technical Reports Server (NTRS)

Ten percent scale models of a Mach 2.2 two dimensional inlet and a Mach 2.0 axisymmetric inlet were tested in the NASA Lewis Research Center 8'x6' Supersonic Wind Tunnel as part of a cooperative effort with the McDonnell Aircraft Company. The objective of this effort was to test methods designed to increase the maneuvering performance of fighter aircraft inlets. Maneuvering improvement concepts were tested up to 40-deg angle of attack for Mach numbers of 0.6 and 0.9, and up to 25 deg for Mach numbers 1.2 and 1.4. Maneuvering improvement concepts included a rotating cowl lip, auxiliary inlets aft of the inlet throat, and a retracting centerbody for the axisymmetric inlet. Test results show that the rotating cowl design was effective in improving subsonic maneuvering performance for both inlets. Auxiliary inlets did not produce significant performance increases for either model. The retracted centerbody resulted in some performance benefits at high angles of attack. None of the maneuvering improvement concepts were effective at Mach 1.2 and 1.4.

Norby, W. P.; Haeffele, B. A.; Burley, R. R.

1986-01-01

318

Perforations in jet engine supersonic inlet increase shock stability  

NASA Technical Reports Server (NTRS)

Modification of a conventional jet engine internal compression supersonic inlet results in increased shock stability and thus, engine instantaneous response to changes in inlet air properties. This technique provides a large amount of bleed near the maximum pressure recovery at the expense of minor bleed flow during critical operation.

Keppler, C. R.

1966-01-01

319

FIELD COMPARISON OF PM10 INLETS AT FOUR LOCATIONS  

EPA Science Inventory

A comprehensive field study was conducted comparing the performance of PM(sub 10) inlets under a variety of field conditions. Inlets for low flow, medium flow, and high flow samplers were evaluated at four sampling locations providing a range of concentrations and particle sizes....

320

76 FR 14803 - Drawbridge Operation Regulation; Townsend Inlet, Avalon, NJ  

Federal Register 2010, 2011, 2012, 2013, 2014

...caused by the temporary deviation. Vessels have two alternate routes by transiting either eight miles to the south through Hereford Inlet or eight miles to the north through Corson Inlet. The drawbridge will be able to open in the event of an...

2011-03-18

321

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

322

Physical controls on the dynamics of inlet sandbar systems  

Microsoft Academic Search

Knowledge of the physical processes acting at inlet systems and their interaction with sediments and sediment bodies is important to the understanding of such environments. The objectives of this study are to identify and assess the relative importance of the controlling processes across the complex sandbar system at the Teign inlet (Teignmouth, UK) through the combined application of a numerical

E. Siegle; D. A. Huntley; M. A. Davidson

2004-01-01

323

A multiobjective shape optimization study for a subsonic submerged inlet  

Microsoft Academic Search

The purpose of the present work is to summarize the findings of a multiobjective shape optimization study conducted for a subsonic submerged air vehicle inlet. The objective functions of the optimization problem are distortion and swirl indices defined by the distribution of flow parameters over the exit cross-section of the inlet. The geometry alteration is performed by placing a protrusion

Ezgi S. Taskinoglu

2004-01-01

324

A Morphing Composite Air Inlet with Multiple Stable Shapes  

Microsoft Academic Search

The morphing air inlet is a structure with shape-changing capability. Shapes include that which is flush with an aerodynamic surface and also a submerged divergent channel suitable for use in an aircraft cooling system. The air inlet structure is multistable in order that it can ‘snap’ open and closed and not require any external holding force to maintain its geometry.

S. Daynes; P. M. Weaver; J. A. Trevarthen

2011-01-01

325

A new system for preventing icing of gas turbine inlets  

Microsoft Academic Search

A new system for preventing condensate and precipitate icing of gas turbine inlet systems has been developed. This system uses a combination heat exchanger\\/moisture separator called an Anti-Ice Moisture Separator (AIMS) to provide icing protection without the need to heat the inlet air to 0 C or above. Turbine exhaust gas heats the AIMS surfaces and thereby prevents ice from

G. R. Gillingham

1976-01-01

326

NISTIR 6458 Characterization of the Inlet Combustion Air in  

E-print Network

NISTIR 6458 Characterization of the Inlet Combustion Air in NIST's Reference Spray Combustion January 2000 #12;ii Contents page Introduction 1 Reference Spray Combustion Facility 3 Numerical;1 Characterization of the Inlet Combustion Air in NIST's Reference Spray Combustion Facility: Effect of Vane Angle

Magee, Joseph W.

327

Computational Study of the Aerodynamic Performance of Subsonic Scarf Inlets  

Microsoft Academic Search

A computational study has been conducted to assess the aerodynamic performance of subsonic scarf inlets. The computations were performed using the WIND 3D Navier-Stokes CFD code. The objective of the study was to investigate the aerodynamic performance of scarf inlets wherein the circumferential extent, ?, over which the transition from the extended lower lip to the non-extended lip was the

John M. Abbott

2004-01-01

328

Liquid air as a coolant for thermal management of long-length HTS cable systems  

NASA Astrophysics Data System (ADS)

Direct current (dc), high temperature superconducting (HTS) cable systems have been suggested as an effective method of transmitting very large amounts of electric power (up to 10 GW) over very long distances (thousands of kilometers). This is made possible mainly by the high-current-carrying capability of the HTS materials when operated below their critical temperatures and by their near zero resistance to constant current. Most HTS cable concepts rely on liquid nitrogen or gaseous helium as the coolant. As an alternative, liquid air offers certain benefits and is discussed here as a cable system coolant. Air has a lower freezing temperature than nitrogen, it can be produced locally, and a liquid air leak will not displace the oxygen in a closed compartment. The dc cable design concept proposed by the Electric Power Research Institute (EPRI) in which the coolant flows in a cryogenic enclosure that includes the cable and a separate return tube, and refrigeration stations positioned every 10 to 20 km is assumed for this analysis. Both go and return lines are contained in a single vacuum envelope. The thermal management of this superconducting cable concept with liquid air in long-distance HTS power cables is developed in this paper. The results are compared to the use of liquid nitrogen, gaseous helium and gaseous hydrogen.

Demko, Jonathan; Hassenzahl, William

2012-06-01

329

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

330

Minimum weight design of a generic axisymmetric inlet  

NASA Technical Reports Server (NTRS)

A new minimum weight design method for high-speed axisymmetric inlets was demonstrated on a generic inlet. The method uses Classical Beam Theory and shell buckling to determine the minimum required equivalent isotropic thickness for a stiffened shell based on prescribed structural design requirements and load conditions. The optimum spacing and equivalent isotropic thickness of ring frame supports are computed to prevent buckling. The method thus develops a preliminary structural design for the inlet and computes the structural weight. Finite element analyses were performed on the resulting inlet design to evaluate the analytical results. Comparisons between the analytical and finite element stresses and deflections identified areas needing improvement in the analytical method. The addition of the deflection due to shear and a torsional buckling failure mode to the new method brought its results in line with those from the finite element analyses. Final validation of the new method will be made using data from actual inlets.

Nadell, Shari-Beth

1996-01-01

331

Inlet and outlet devices for rotary blood pumps.  

PubMed

The purposes of inlet and outlet devices for rotary blood pumps, including inducers and diffusers for axial pumps, inlet and exit volutes for centrifugal pumps, and inlet and outlet cannulas, are to guide the blood into the impeller, where the blood is accelerated, and to convert the high kinetic energy into pressure after the impeller discharge, respectively. The designs of the inlet and outlet devices have an important bearing on the pump performance. Their designs are highly dependent on computational fluid dynamics (CFD) analysis, guided by intuition and experience. For inlet devices, the design objectives are to eliminate separated flow, to minimize recirculation, and to equalize the radial components of velocity. For outlet devices, the design goals are to reduce speed, to minimize energy loss, and to avoid flow separation and whirl. CFD analyses indicate the velocity field and pressure distribution. Geometrical optimization of these components has been implemented in order to improve the flow pattern. PMID:15384997

Song, Xinwei; Wood, Houston G; Allaire, Paul E; Antaki, James F; Olsen, Don B

2004-10-01

332

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

333

Enhancement of performance of gas turbine engines by inlet air cooling and cogeneration system  

Microsoft Academic Search

It is known that the efficiency of the gas turbine engine is relatively low at design point and it deteriorates further at part load and at off-design high ambient temperatures.Therefore, this work comprises the study of adding an inlet air precooler connected to the evaporator of an aqua ammonia absorption chiller which is driven by the tail-end heat recovered from

Yousef S. H. Najjar

1996-01-01

334

Study of inlet materials for sampling atmospheric nitric acid  

SciTech Connect

The adsorption of nitric acid (HNO{sub 3}) from a flowing gas stream is studied for a variety of wall materials to determine their suitability for use in atmospheric sampling instruments. Parts per billion level mixtures of HNO{sub 3} in synthetic air flow through tubes of different materials such that >80% of the molecules interact with the walls. A chemical ionization mass spectrometer with a fast time response and high sensitivity detects HNO{sub 3} that is not adsorbed on the tube walls. Less than 5% of available HNO{sub 3} is adsorbed on Teflon fluoropolymer tubing after 1 min of HNO{sub 3} exposure, whereas >70% is lost on walls made of stainless steel, glass, fused silica, aluminum, nylon, silica-steel, and silane-coated glass. Glass tubes exposed to HNO{sub 3} on the order of hours passivate with HNO{sub 3} adsorption dropping to zero. The adsorption of HNO{sub 3} on PFA Teflon tubing (PFA) is nearly temperature-independent from 10 to 80 C, but below {minus}10 C nearly all HNO{sub 3} that interacts with PFA is reversibly adsorbed. In ambient and synthetic air, humidity increases HNO{sub 3} adsorption. The results suggest that Teflon at temperatures above 10 C is an optimal choice for inlet surfaces used for in situ measurements of HNO{sub 3} in the ambient atmosphere.

Neuman, J.A.; Huey, L.G.; Ryerson, T.B.; Fahey, D.W. [NOAA, Boulder, CO (United States)] [NOAA, Boulder, CO (United States); [Univ. of Colorado/NOAA, Boulder, CO (United States). Cooperative Inst. for Research in Environmental Sciences

1999-04-01

335

Journal of Coastal Research SI 59 98-110 West Palm Beach, Florida 2011 New Ebb-Tidal Delta at an Old Inlet, Shark River Inlet, New Jersey  

E-print Network

at an Old Inlet, Shark River Inlet, New Jersey Tanya M. Beck and Nicholas C. Kraus ABSTRACT BECK, T.M. and KRAUS, N.C., 2011. New Ebb-Tidal Delta at an Old Inlet, Shark River Inlet, New Jersey. In: Roberts, T of Coastal Research, Special Issue, No. 59, pp. 98-110. West Palm Beach (Florida), ISSN 0749-0208. Shark

US Army Corps of Engineers

336

A probabilistic method for determining effluent temperature limits for flow instability for SRS reactors  

SciTech Connect

This manual describes the uncertainty analysis used to determine the effluent temperature limits for a Mark 22 charge in the Savannah River Site production reactors. The postulated accident scenario is a DEGB/LOCA resulting from a coolant pipe break at the plenum inlet accompanied by the safety rod failure described in the previous chapter. The analysis described in this manual is used to calculate the limits for the flow instability phase of the accident. For this phase of the accident, the limits criterion is that the Stanton number does not exceed 0.00455 [1]. The limits are determined for a specified 84% probability that the Stanton number will not exceed 0.00455 in any assembly in the core.

Hardy, B.J.; White, A.M.

1990-06-01

337

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

338

The BLOW-3A: A theoretical model to describe transient two phase flow conditions in Liquid Metal Fast Breeder Reactor (LMFBR) coolant channels  

NASA Astrophysics Data System (ADS)

The theoretical background of the BLOW-3A program is reported, including the basic equations used to determine temperature fields in the fuel, clad, coolant and structure material as well as the coolant dynamics in single and two-phase flow conditions. The two-phase flow model assumes an annular flow regime. Special aspects to calculate two-phase pressure drops for these conditions are discussed. Examples of the experimental validation of the program are given.

Bottoni, M.; Struwe, D.

339

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

340

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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

341

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

Code of Federal Regulations, 2010 CFR

...false Cook Inlet Intrastate Air Quality Control Region. 81.54 Section...PURPOSES Designation of Air Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet...

2010-07-01

342

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. PMID:24348146

Wang, Lei; Cao, Shibin

2013-01-01

343

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

344

Flow Simulation of Supersonic Inlet with Bypass Annular Duct  

NASA Technical Reports Server (NTRS)

A relaxed isentropic compression supersonic inlet is a new concept that produces smaller cowl drag than a conventional inlet, but incurs lower total pressure recovery and increased flow distortion in the (radially) outer flowpath. A supersonic inlet comprising a bypass annulus to the relaxed isentropic compression inlet dumps out airflow of low quality through the bypass duct. A reliable computational fluid dynamics solution can provide considerable useful information to ascertain quantitatively relative merits of the concept, and further provide a basis for optimizing the design. For a fast and reliable performance evaluation of the inlet performance, an equivalent axisymmetric model whose area changes accounts for geometric and physical (blockage) effects resulting from the original complex three-dimensional configuration is proposed. In addition, full three-dimensional calculations are conducted for studying flow phenomena and verifying the validity of the equivalent model. The inlet-engine coupling is carried out by embedding numerical propulsion system simulation engine data into the flow solver for interactive boundary conditions at the engine fan face and exhaust plane. It was found that the blockage resulting from complex three-dimensional geometries in the bypass duct causes significant degradation of inlet performance by pushing the terminal normal shock upstream.

Kim, HyoungJin; Kumano, Takayasu; Liou, Meng-Sing; Povinelli, Louis A.; Conners, Timothy R.

2011-01-01

345

Effects of coolant volatility on simulated HCDA bubble expansions. [LMFBR  

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). In past experiments, water was used to simulate the sodium coolant in the prototype. In these experiments, 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.

Tobin, R.J.

1980-09-01

346

Observations of Currents in Two Tidally Modulated Inlets  

NASA Astrophysics Data System (ADS)

Observations of currents obtained in two tidally modulated inlets are used to examine the spatial evolution of the vertical structure in hourly averaged mean flow and at tidal frequencies. Field experiments of 30 day duration were conducted at Hampton/Seabrook Harbor, NH, in the Fall of 2011 and again at New River Inlet, NC, in the spring of 2012. The temporal variation and vertical structure of the currents were observed with 600 khz and 1200 khz RDI Acoustic Doppler Current Profilers (ADCP) deployed on low-profile bottom tripods just outside and within the inlet mouth, and with a Nortek Aquadopp Profiler mounted on a jetted pipe on the flank of the inlet channel. Across-inlet current profiles were obtained at each site at various tidal stages with a 1200 khz RDI vessel-mounted ADCP onboard the personal watercraft (the Coastal Bathymetry Survey System, or CBASS) that transited the inlet multiple times at various spatial locations. Flows within the inlet were dominated by semi-diurnal tides, ranging from 2.5 to 4 m in elevation at Hampton/Seabrook Harbor with velocities exceeding 3 m/s, and tides ranging from 1 to 1.5 m in elevation at New River Inlet with velocities exceeding 2 m/s. Flows sampled with the CBASS will be used to examine the horizontal and vertical variation in mean currents (averaged over about 20 - 40 min) at various tidal stages. Currents sampled with the fixed instruments will be used to examine the temporal variation in amplitude and direction of mean currents (averaged over 30 - 60 min) as a function of depth, as well as the amplitude, phase, and rotational structure at tidal frequencies. Observations from the two field sites will be compared and discussed in terms of the spatial and temporal evolution from outside the river mouth to the inner inlet channels over the fortnightly sampling period.

Lippmann, T. C.; Irish, J. D.; Hunt, J.

2012-12-01

347

Modulation of the neutron field in the multiplying condensed matter and coolant  

SciTech Connect

The spatial damping of acoustic, neutron and thermal branches of oscillations are found in neutron multiplying medium with coolant. All three branches give additive contribution to the neutron density oscillations. However, their wave numbers and coefficients of spatial damping (at the same frequency) differ greatly from the sound with its high phase velocity and small attenuation to the neutron wave with the damping length, which is comparable with its wavelength. A spatial growth of neutron density oscillations is found in the case of large frequency of neutron capture and weak coupling of neutron density and temperature branches of oscillations. This fact is of importance for the noise diagnostics of the multiplying medium with coolant. The results can be applied to the development of the methods of noise diagnostics of the in core reactor equipment.

Vodyanitskii, A. A.; Slyusarenko, Yu. V. [Akhiezer Institute for Theoretical Physics, NSC KIPT, 1 Akademicheskaya Str., 61108 Kharkiv (Ukraine)

2009-12-14

348

Flow boiling with enhancement devices for cold plate coolant channel design  

NASA Technical Reports Server (NTRS)

Future space exploration and commercialization will require more efficient heat rejection systems. For the required heat transfer rates, such systems must use advanced heat transfer techniques. Forced two phase flow boiling heat transfer with enhancements falls in this category. However, moderate to high quality two phase systems tend to require higher pressure losses. This report is divided into two major parts: (1) Multidimensional wall temperature measurement and heat transfer enhancement for top heated horizontal channels with flow boiling; and (2) Improved analytical heat transfer data reduction for a single side heated coolant channel. Part 1 summarizes over forty experiments which involve both single phase convection and flow boiling in a horizontal channel heated externally from the top side. Part 2 contains parametric dimensionless curves with parameters such as the coolant channel radius ratio, the Biot number, and the circumferential coordinate.

Boyd, Ronald D.

1991-01-01

349

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

350

Feasibility study of inlet shock stability system of YF-12  

NASA Technical Reports Server (NTRS)

The feasibility of self actuating bleed valves as a shock stabilization system in the inlet of the YF-12 is considered for vortex valves, slide valves, and poppet valves. Analytical estimation of valve performance indicates that only the slide and poppet valves located in the inlet cowl can meet the desired steady state stabilizing flows, and of the two the poppet valve is substantially faster in response to dynamic disturbances. The poppet valve is, therefore, selected as the best shock stability system for the YF-12 inlet.

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

1972-01-01

351

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

352

An experimental investigation of flow control for supersonic inlets  

E-print Network

the inlet geometry (not changing your position on the y-axis), the only way to get the inlet started from here is to increase M1 to M17 (vii) and then reduce it back toM14. This is known as over-speeding the inlet. In general, it is unlikely that you... ), Delery and Marvin (1986), or Babinsky and Harvey (2011). Alongside these reviews, some of the best data obtained with the simplest normal SWBLI configuration (the normal SWBLI in a constant area channel) is that reported by East (1976) and Sawyer and Long...

Titchener, Neil

2013-07-09

353

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

354

High-speed inlet research program and supporting analysis  

NASA Technical Reports Server (NTRS)

The technology challenges faced by the high speed inlet designer are discussed by describing the considerations that went into the design of the Mach 5 research inlet. It is shown that the emerging three dimensional viscous computational fluid dynamics (CFD) flow codes, together with small scale experiments, can be used to guide larger scale full inlet systems research. Then, in turn, the results of the large scale research, if properly instrumented, can be used to validate or at least to calibrate the CFD codes.

Coltrin, Robert E.

1990-01-01

355

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

356

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

357

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

358

A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems  

NASA Technical Reports Server (NTRS)

This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H20 for the HRS pumped loop coolant working fluid. A detailed Microsoft Excel (Microsoft Corporation, Redmond, WA) analytical model, HRS_Opt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

Mason, Lee S.; Siamidis, John

2006-01-01

359

A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems  

NASA Astrophysics Data System (ADS)

This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H2O for the HRS pumped loop coolant working fluid. A detailed excel analytical model, HRS_Opt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

Siamidis, John; Mason, Lee

2006-01-01

360

Tables of thermodynamic properties of helium magnet coolant  

SciTech Connect

The most complete treatment of the thermodynamic properties of helium at the present time is the monograph by McCarty: Thermodynamic Properties of Helium 4 from 2 to 1500 K at Pressures to 10{sup 8} Pa'', Robert D. McCarty, Journal of Physical and Chemical Reference Data, Vol. 2, page 923--1040 (1973). In this work the complete range of data on helium is examined and the P-V-T surface is described by an equation of state consisting of three functions P(r,T) covering different regions together with rules for making the transition from one region to another. From this thermodynamic compilation together with correlations of the transport properties of helium was published the well-known NBS Technical Note: Thermophysical Properties of Helium 4 from 2 to 1500 K with pressures to 1000 Atmospheres'', Robert D. McCarty, US Department of Commerce, National Bureau of Standards Technical Note 631 (1972). This is the standard reference for helium cryogenics. The NBS 631 tables cover a wide range of temperature and pressure, and as a consequence, the number of points tabulated in the region of the single phase coolant for the SSC magnets are relatively few. The present work sets out to cover the range of interest in more detail in a way that is consistent with NBS 631. This new table is essentially identical to the older one and can be used as an auxiliary to it.

McAshan, M.

1992-07-01

361

Tables of thermodynamic properties of helium magnet coolant. Revision A  

SciTech Connect

The most complete treatment of the thermodynamic properties of helium at the present time is the monograph by McCarty: ``Thermodynamic Properties of Helium 4 from 2 to 1500 K at Pressures to 10{sup 8} Pa``, Robert D. McCarty, Journal of Physical and Chemical Reference Data, Vol. 2, page 923--1040 (1973). In this work the complete range of data on helium is examined and the P-V-T surface is described by an equation of state consisting of three functions P(r,T) covering different regions together with rules for making the transition from one region to another. From this thermodynamic compilation together with correlations of the transport properties of helium was published the well-known NBS Technical Note: ``Thermophysical Properties of Helium 4 from 2 to 1500 K with pressures to 1000 Atmospheres``, Robert D. McCarty, US Department of Commerce, National Bureau of Standards Technical Note 631 (1972). This is the standard reference for helium cryogenics. The NBS 631 tables cover a wide range of temperature and pressure, and as a consequence, the number of points tabulated in the region of the single phase coolant for the SSC magnets are relatively few. The present work sets out to cover the range of interest in more detail in a way that is consistent with NBS 631. This new table is essentially identical to the older one and can be used as an auxiliary to it.

McAshan, M.

1992-07-01

362

Tables of thermodynamic properties of helium magnet coolant, revision A  

NASA Astrophysics Data System (ADS)

The most complete treatment of the thermodynamic properties of helium at the present time is the monograph by McCarty: 'Thermodynamic Properties of Helium 4 from 2 to 1500 K at Pressures to 10(exp 8) Pa', Robert D. McCarty, Journal of Physical and Chemical Reference Data, Vol. 2, page 923-1040 (1973). In this work the complete range of data on helium is examined and the P-V-T surface is described by an equation of state consisting of three functions P(r,T) covering different regions together with rules for making the transition from one region to another. From this thermodynamic compilation together with correlations of the transport properties of helium was published the well-known NBS Technical Note: 'Thermophysical Properties of Helium 4 from 2 to 1500 K with pressures to 1000 Atmospheres', Robert D. McCarty, US Department of Commerce, National Bureau of Standards Technical Note 631 (1972). This is the standard reference for helium cryogenics. The NBS 631 tables cover a wide range of temperature and pressure, and as a consequence, the number of points tabulated in the region of the single phase coolant for the SSC magnets are relatively few. The present work sets out to cover the range of interest in more detail in a way that is consistent with NBS 631. This new table is essentially identical to the older one and can be used as an auxiliary to it.

McAshan, M.

1992-07-01

363

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

364

Some flow phenomena in a constant area duct with a Borda type inlet including the critical region  

NASA Technical Reports Server (NTRS)

Mass limiting flow characteristics for a 55 L/D tube with a Borda type inlet were assessed over large ranges of temperature and pressure, using fluid nitrogen. Under certain conditions, separation and pressure drop at the inlet was sufficiently strong to permit partial vaporization and the remaining fluid flowed through the tube as if it were a free jet. An empirical relation was determined which defines conditions under which this type of flow can occur. A flow coefficient is presented which enables estimations of flow rates over the experimental range. A flow rate stagnation pressure map for selected stagnation isotherms and pressure profiles document these flow phenomena.

Hendricks, R. C.; Simoneau, R. J.

1978-01-01

365

Shuttle Centaur engine cooldown evaluation and effects of expanded inlets on start transient  

NASA Technical Reports Server (NTRS)

As part of the integration of the RL10 engine into the Shuttle Centaur vehicle, a satisfactory method of conditioning the engine to operating temperatures had to be established. This procedure, known as cooldown, is different from the existing Atlas Centaur due to vehicle configuration and mission profile differenced. The program is described, and the results of a Shuttle Centaur cooldown program are reported. Mission peculiarities cause substantial variation in propellant inlet conditions between the substantiated Atlas Centaur and Shuttle Centaur with the Shuttle Centaur having much larger variation in conditions. A test program was conducted to demonstrate operation of the RL10 engine over the expanded inlet conditions. As a result of this program, the Shuttle Centaur requirements were proven satisfactory. Minor configuration changes incorporated as a result of this program provide substantial reduction in cooldown propellant consumption.

1987-01-01

366

INVESTIGATION OF CLEANER TECHNOLOGIES TO MINIMIZE AUTOMOTIVE COOLANT WASTES  

EPA Science Inventory

The US Environmental Protection Agency in cooperation with the State of New Jersey evaluated chemical filtration and distillation technologies designed to recycle automotive and heavy-duty engine coolants. These evaluations addressed the product quality, waste reduction and econo...

367

EVALUATION OF FILTRATION AND DISTILLATION METHODS FOR RECYCLING AUTOMOTIVE COOLANT  

EPA Science Inventory

This evaluation addresses the product quality, waste reduction, and economic issues involved in recycling automotive engine coolants at a New Jersey Department of Transportation garage. he specific recycling units evaluated are based on the technologies of filtration and distilla...

368

Unsteady Analysis of Inlet-Compressor Acoustic Interactions Using Coupled 3-D and 1-D CFD Codes  

NASA Technical Reports Server (NTRS)

It is well known that the dynamic response of a mixed compression supersonic inlet is very sensitive to the boundary condition imposed at the subsonic exit (engine face) of the inlet. In previous work, a 3-D computational fluid dynamics (CFD) inlet code (NPARC) was coupled at the engine face to a 3-D turbomachinery code (ADPAC) simulating an isolated rotor and the coupled simulation used to study the unsteady response of the inlet. The main problem with this approach is that the high fidelity turbomachinery simulation becomes prohibitively expensive as more stages are included in the simulation. In this paper, an alternative approach is explored, wherein the inlet code is coupled to a lesser fidelity 1-D transient compressor code (DYNTECC) which simulates the whole compressor. The specific application chosen for this evaluation is the collapsing bump experiment performed at the University of Cincinnati, wherein reflections of a large-amplitude acoustic pulse from a compressor were measured. The metrics for comparison are the pulse strength (time integral of the pulse amplitude) and wave form (shape). When the compressor is modeled by stage characteristics the computed strength is about ten percent greater than that for the experiment, but the wave shapes are in poor agreement. An alternate approach that uses a fixed rise in duct total pressure and temperature (so-called 'lossy' duct) to simulate a compressor gives good pulse shapes but the strength is about 30 percent low.

Suresh, A.; Cole, G. L.

2000-01-01

369

40 CFR 91.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2013 CFR

...restrictions that are specified by the manufacturer for that particular engine. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the highest emission...

2013-07-01

370

40 CFR 91.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2011 CFR

...restrictions that are specified by the manufacturer for that particular engine. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the highest emission...

2011-07-01

371

40 CFR 91.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2010 CFR

...restrictions that are specified by the manufacturer for that particular engine. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the highest emission...

2010-07-01

372

40 CFR 91.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2012 CFR

...restrictions that are specified by the manufacturer for that particular engine. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the highest emission...

2012-07-01

373

40 CFR 91.407 - Engine inlet and exhaust systems.  

Code of Federal Regulations, 2014 CFR

...restrictions that are specified by the manufacturer for that particular engine. (b) The air inlet filter system and exhaust muffler system combination used on the test engine must be the systems expected to yield the highest emission...

2014-07-01

374

Status of the variable diameter centerbody inlet program  

NASA Technical Reports Server (NTRS)

The Variable Diameter Centerbody (VDC) inlet is an ongoing research program at LeRC. The VDC inlet is a mixed compression, axisymmetric inlet that has potential application on the next generation supersonic transport. This inlet was identified as one of the most promising axisymmetric concepts for supersonic cruise aircraft during the SCAR program in the late 1970's. Some of its features include high recovery, low bleed, good angle-of-attack tolerance, and excellent engine airflow matching. These features were demonstrated at LeRC in the past by the design and testing of fixed hardware models. A current test program in the LeRC 10' x 10' Supersonic Wind Tunnel (SWT) will attempt to duplicate these features on model hardware that actually incorporates a flight-like variable diameter centerbody mechanism.

Saunders, John D.; Linne, A. A.

1992-01-01

375

Hydrodynamics and sediment transport in a southeast Florida tidal inlet  

PubMed Central

A three-dimensional ocean circulation model is used to investigate the hydrodynamics of a tidal inlet and deltas system in Southeast Florida, and to understand the consequences for suspended and bedload sediment transport patterns. The model reproduces observed tidal currents and provides insight about residual currents caused by spatial asymmetries in the inlet throat and tidal deltas during ebb and flood flows. A particle-tracking approach for suspended and bedload sediment transport is used to simulate deposition patterns for different particle sizes. The simulation results qualitatively correlate with the distribution of sediment characteristics within the tidal inlet and deltas system and demonstrate sensitivity to the choice of advection velocities (e.g., near-bottom versus depth-averaged) and regions of sediment origin. Furthermore, the distinction between suspended and bedload transport as a function of particle size indicates significant differences in deposition patterns and their potential connection to geomorphologic features of the tidal inlet and deltas system. PMID:19838314

Fiechter, Jerome; Steffen, Kelley L.; Mooers, Christopher N.K.; Haus, Brian K.

2009-01-01

376

Flow analysis and control in a subsonic inlet  

E-print Network

S-duct inlets are commonly used on subsonic cruise missiles, as they offer a good compromise between compactness, low observability and aerodynamic performance. Though currently used S-ducts exhibit good performance in ...

Tournier, Serge (Serge E.)

2005-01-01

377

Theoretical Investigation of Submerged Inlets at Low Speeds  

NASA Technical Reports Server (NTRS)

The general characteristics of the flow field in a submerged air inlet are investigated by theoretical, wind-tunnel, and visual-flow studies. Equations are developed for calculating the laminar and turbulent boundary-layer growth along the ramp floor for parallel, divergent, and convergent ramp walls, and a general equation is derived relating the boundary-layer pressure losses to the boundary-layer thickness. It is demonstrated that the growth of the boundary layer on the floor of the divergent-ramp inlet is retarded and that a vortex pair is generated in such an inlet. Functional relationships are established between the pressure losses in the vortices and the geometry of the inlet. A general discussion of the boundary layer and vortex formations is included, in which variations of the various losses and of the incremental external drag with mass-flow ratio are considered. Effects of compressibility are also discussed.

Sacks, Alvin H.; Spreiter, John R.

1951-01-01

378

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

379

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

Code of Federal Regulations, 2012 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...

2012-10-01

380

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

Code of Federal Regulations, 2011 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...

2011-10-01

381

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

Code of Federal Regulations, 2010 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...

2010-10-01

382

Three dimensional viscous analysis of a hypersonic inlet  

NASA Technical Reports Server (NTRS)

The flow fields in supersonic/hypersonic inlets are currently being studied at NASA Lewis Research Center using 2- and 3-D full Navier-Stokes and Parabolized Navier-Stokes solvers. These tools have been used to analyze the flow through the McDonnell Douglas Option 2 inlet which has been tested at Calspan in support of the National Aerospace Plane Program. Comparisons between the computational and experimental results are presented. These comparisons lead to better overall understanding of the complex flows present in this class of inlets. The aspects of the flow field emphasized in this work are the 3-D effects, the transition from laminar to turbulent flow, and the strong nonuniformities generated within the inlet.

Reddy, D. R.; Smith, G. E.; Liou, M.-F.; Benson, Thomas J.

1989-01-01

383

INTERIOR TOWER ENTRANCE, LOOKING NORTH. Oregon Inlet Coast Guard ...  

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

INTERIOR TOWER ENTRANCE, LOOKING NORTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

384

INTERIOR INNKEEPER FAMILY ROOM, LOOKING NORTH. Oregon Inlet Coast ...  

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

INTERIOR INNKEEPER FAMILY ROOM, LOOKING NORTH. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

385

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

386

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

387

Study of extended life coolant with suspended carbon nanotubes  

NASA Astrophysics Data System (ADS)

Utilizing an experimental facility which was prepared to conduct performance tests on heat exchangers; experiments were completed in an attempt to see verifiable improvements in overall heat transfer coefficient in engine coolant with nanoparticles suspended at different weight percentages. The different fluids tested were: base ELC (Extended Life Coolant), ELC with 0.002 wt% CNT (Carbon Nanotubes), ELC with 0.02 wt% CNT, ELC with 0.02 wt% MWNT's (Multiwalled Nanotubes) and water. The volume percents range from 0.00164 volume% to 0.0164 volume% which seemed quite small, but according to Caterpillar representatives, were the best concentration. These fluids were tested at standard flowrates which this type of heat exchanger would be used in as well as a higher air flowrate and lower coolant flowrates in an attempt to gather more verifiable data. Results were obtained regarding the change in heat transfer ability of engine coolant with suspended nanoparticles. For this system under these specific conditions, there was verifiably no increase in UA as nanoparticles were added to the coolant. The benefits of adding nanoparticles to engine coolant have potential to be great, but the cost of nanoparticles and difficulty keeping them suspended may outweigh any benefits obtainable in this type of set up.

Overturf, Logan

388

Utilizing numerical techniques in turbofan inlet acoustic suppressor design  

NASA Technical Reports Server (NTRS)

Numerical theories in conjunction with previously published analytical results are used to augment current analytical theories in the acoustic design of a turbofan inlet nacelle. In particular, a finite element-integral theory is used to study the effect of the inlet lip radius on the far field radiation pattern and to determine the optimum impedance in an actual engine environment. For some single mode JT15D data, the numerical theory and experiment are found to be in a good agreement.

Baumeister, K. J.

1982-01-01

389

Properties and stability of a Texas barrier beach inlet  

E-print Network

. . . . . , . . . . . . . . . . . . . . , . . . 52 25 26 Tidal Differential, 20 February to 15 March, 1971 . 55 Tidal Differential, 16 March to 6 April, 1971 27 Non-Astronomical Sea Level and Corresponding Wind Regimes, Inlet Tide Station . . . . . . . . . . . . 58 28 Inlet Tide Gage Record..., 20 March, 1971 61 Computed Tidal Current Velocity, 20 February Through 3 April, 1971 . . . . . . . . . . . . . . . . . . . 65 30 Observed Current Velocity Vs. Tidal Differential . 67 31 32 33 34 35 Location of Beach Profiles East Spit Beach...

Mason, Curtis

1971-01-01

390

A multiobjective shape optimization study for a subsonic submerged inlet  

NASA Astrophysics Data System (ADS)

The purpose of the present work is to summarize the findings of a multiobjective shape optimization study conducted for a subsonic submerged air vehicle inlet. The objective functions of the optimization problem are distortion and swirl indices defined by the distribution of flow parameters over the exit cross-section of the inlet. The geometry alteration is performed by placing a protrusion in the shape of a fin on the baseline inlet surface. Thus, the design variables of the optimization problem are chosen to be the geometrical parameters defining the fin protrusion; namely fin height, length and incidence angle. The Trade Off (also known as epsilon-constraint) method is employed for finding the Pareto optimal set formed by the nondominated solutions of the feasible design space. Since the flow domain solution is required for every step along the line search, an automated optimization loop is constructed by integrating the optimizer with a surface modeler, a mesh generator and a flow solver through which the flow parameters over the compressor face are computed. In addition, the trade study for fin protrusion, the analyses and the comparison of the baseline and Pareto optimal solutions are presented and observations concerning grid resolution and convergence behaviour are discussed. The results display an irregular and discontinuous Pareto optimal set. Optimum inlet designs are scattered in two regions from which one representative inlet design is chosen and analyzed. As a result, it is concluded that an inlet designer has two options within the framework of this optimization study: an inlet design with high swirl but low distortion or an inlet design with low swirl but higher distortion.

Taskinoglu, Ezgi S.

391

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

392

Numerical 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. Numerical simulations have been carried out which evaluate the effectiveness of steady and unsteady actuation for active flow control in an aggressive S-duct inlet, L/D = 1.5 (at flow conditions representative of flight conditions). These simulations were performed in close co-ordination with the experiments to be able to validate CFD predictions and further provide a complementary and detailed view of the flow field. Comparisons will be made between: steady and unsteady blowing from a single 2-D tangential slit. Evaluations criteria will include total pressure recovery, AIP distortion levels, and unsteady pressure fluctuations. It is noteworthy to mention that the agreement between the CFD predictions and the experimental measurements were found to be very good.

Jansen, Kenneth; Sahni, Onkar; Amitay, Michael

2009-11-01

393

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

394

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

395

Mach 4 Test Results of a Dual-Flowpath, Turbine Based Combined Cycle Inlet  

NASA Technical Reports Server (NTRS)

An experimental study was conducted to evaluate the performance of a turbine based combined cycle (TBCC) inlet concept, consisting of a low speed turbojet inlet and high speed dual-mode scramjet inlet. The main objectives of the study were (1) to identify any interactions between the low and the high speed inlets during the mode transition phase in which both inlets are operating simultaneously and (2) to determine the effect of the low speed inlet operation on the performance of the high speed inlet. Tests were conducted at a nominal freestream Mach number of 4 using an 8 percent scale model representing a single module of a TBCC inlet. A flat plate was installed upstream of the model to produce a turbulent boundary layer which simulated the full-scale vehicle forebody boundary layer. A flowmeter/back pressure device, with remote actuation, was attached aft of the high speed inlet isolator to simulate the back pressure resulting from dual-mode scramjet combustion. Results indicate that the inlets did not interact with each other sufficiently to affect inlet operability. Flow spillage resulting from a high speed inlet unstart did not propagate far enough upstream to affect the low speed inlet. Also, a low speed inlet unstart did not cause the high speed inlet to unstart. The low speed inlet improved the performance of the high speed inlet at certain conditions by diverting a portion of the boundary layer generated on the forebody plate.

Albertson, Cindy w.; Emami, Saied; Trexler, Carl A.

2006-01-01

396

Investigation of Power Requirements for Ice Prevention and Cyclical De-Icing of Inlet Guide Vanes with Internal Electric Heaters  

NASA Technical Reports Server (NTRS)

An investigation was conducted to determine the electric power requirements necessary for ice protection of inlet guide vanes by continuous heating and by cyclical de-icing. Data are presented to show the effect of ambient-air temperature, liquid-water content, air velocity, heat-on period, and cycle times on the power requirements for these two methods of ice protection. The results showed that for a hypothetical engine using 28 inlet guide vanes under similar icing conditions, cyclical de-icing can provide a total power saving as high as 79 percent over that required for continuous heating. Heat-on periods in the order of 10 seconds with a cycle ratio of about 1:7 resulted in the best over-all performance with respect to total power requirements and aerodynamic losses during the heat-off period. Power requirements reported herein may be reduced by as much as 25 percent by achieving a more uniform surface-temperature distribution. A parameter in terms of engine mass flow, vane size, vane surface temperature, and the icing conditions ahead of the inlet guide vanes.was developed by which an extension of the experimental data to icing conditions and inlet guide vanes, other than those investigated was possible.

VonGlahn, Uwe; Blatz, Robert E.

1950-01-01

397

Effect of variable inlet guide vanes on the operating characteristics of a tilt nacelle inlet/powered fan model  

NASA Technical Reports Server (NTRS)

The effects of a variable inlet guide vane (VIGV) assembly on the operating characteristics of a V/STOL inlet and on the performance of a 20-in. (0.508-m) diameter fan engine were investigated. The data indicate that the VIGVs are effective thrust modulators over a wide range of free-stream velocities, nacelle angles of attack, and fan speeds. The thrust modulation ranges, including choking limits, fan stall limits, and inlet separation boundaries are presented. The presence of the VIGV assembly causes significant losses in inlet angle-of-attack capability and generally increases the blade stress levels at all limit conditions except at high angle of attack and high free-stream velocity. Reducing the fan nozzle exit area limited the positive VIGV actuation range and consequently decreased the range of thrust modulation at all limit conditions except at both high free-stream velocity and high angle of attack conditions.

Woollett, R. R.; Pontonides, H. C.

1987-01-01

398

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

NASA Technical Reports Server (NTRS)

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

Hall, Charles F; Barclay, F Dorn

1948-01-01

399

Calculated effects of dissolved gases on the thermodynamic properties of Hanford N Reactor primary coolant  

SciTech Connect

It has been noted that for present and anticipated modes of operation the Hanford N-Reactor primary coolant may bear thermohydraulically significant amounts of dissolved hydrogen, nitrogen, and ammonia. To investigate this possibility, calculations were made of the specific volume and specific enthalpy of aqueous primary coolant from available data and reasonable approximations over the necessary ranges of temperature and pressure. A computer program which produces a steam table of these properties, as well as compositions, has been coded to provide tables of the bubble line, dew line, superheated-vapor - compressed liquid, and two phase-to-20% void regimes from 32/sup 0/F to 630/sup 0/F and from 14 psia to 2100 psia. This program will provide the tables for any inputted coolant composition of water with 0.01 to 200 ppM NH/sub 3/, 0.01 to 50 ppM H/sub 2/, and 0.01 to 150 ppM N/sub 2/, or so long as the mole fraction of water remains above 0.999. Alteration for other water chemistries is not difficult.

Bechtold, D.B.

1982-06-23

400

Nuclear-radiation-actuated valve. [Patent application; for increasing coolant flow to blanket  

DOEpatents

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 through operation of the breeder reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

Christiansen, D.W.; Schively, D.P.

1982-01-19

401

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

402

Influence of coolant pH on corrosion of 6061 aluminum under reactor heat transfer conditions  

SciTech Connect

To support the design of the Advanced Neutron Source (ANS), an experimental program was conducted wherein aluminum alloy specimens were exposed at high heat fluxes to high-velocity aqueous coolants in a corrosion test loop. The aluminum alloys selected for exposure were candidate fuel cladding materials, and the loop system was constructed to emulate the primary coolant system for the proposed ANS reactor. One major result of this program has been the generation of an experimental database defining oxide film growth on 6061 aluminum alloy cladding. Additionally, a data correlation was developed from the database to permit the prediction of film growth for any reasonable thermal-hydraulic excursion. This capability was utilized effectively during the conceptual design stages of the reactor. During the course of this research, it became clear that the kinetics of film growth on the aluminum alloy specimens were sensitively dependent on the chemistry of the aqueous coolant and that relatively small deviations from the intended pH 5 operational level resulted in unexpectedly large changes in the corrosion behavior. Examination of the kinetic influences and the details of the film morphology suggested that a mechanism involving mass transport from other parts of the test loop was involved. Such a mechanism would also be expected to be active in the operating reactor. This report emphasizes the results of experiments that best illustrate the influence of the nonthermal-hydraulic parameters on film growth and presents data to show that comparatively small variations in pH near 5.0 invoke a sensitive response. Simply, for operation in the temperature and heat flux range appropriate for the ANS studies, coolant pH levels from 4.5 to 4.9 produced significantly less film growth than those from pH 5.1 to 6. A mechanism for this behavior based on the concept of treating the entire loop as an active corrosion system is presented.

Pawel, S.J.; Felde, D.K.; Pawel, R.E.

1995-10-01

403

Numerical Simulation of Non-Rotating and Rotating Coolant Channel Flow Fields. Part 1  

NASA Technical Reports Server (NTRS)

Future generations of ultra high bypass-ratio jet engines will require far higher pressure ratios and operating temperatures than those of current engines. For the foreseeable future, engine materials will not be able to withstand the high temperatures without some form of cooling. In particular the turbine blades, which are under high thermal as well as mechanical loads, must be cooled. Cooling of turbine blades is achieved by bleeding air from the compressor stage of the engine through complicated internal passages in the turbine blades (internal cooling, including jet-impingement cooling) and by bleeding small amounts of air into the boundary layer of the external flow through small discrete holes on the surface of the blade (film cooling and transpiration cooling). The cooling must be done using a minimum amount of air or any increases in efficiency gained through higher operating temperature will be lost due to added load on the compressor stage. Turbine cooling schemes have traditionally been based on extensive empirical data bases, quasi-one-dimensional computational fluid dynamics (CFD) analysis, and trial and error. With improved capabilities of CFD, these traditional methods can be augmented by full three-dimensional simulations of the coolant flow to predict in detail the heat transfer and metal temperatures. Several aspects of turbine coolant flows make such application of CFD difficult, thus a highly effective CFD methodology must be used. First, high resolution of the flow field is required to attain the needed accuracy for heat transfer predictions, making highly efficient flow solvers essential for such computations. Second, the geometries of the flow passages are complicated but must be modeled accurately in order to capture all important details of the flow. This makes grid generation and grid quality important issues. Finally, since coolant flows are turbulent and separated the effects of turbulence must be modeled with a low Reynolds number turbulence model to accurately predict details of heat transfer.

Rigby, David L.

2000-01-01

404

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

405

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

406

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

407

77 FR 6065 - Proposed Information Collection; Comment Request; Cook Inlet Beluga Whale Economic Survey  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request; Cook Inlet Beluga Whale Economic Survey AGENCY: National Oceanic...Abstract The population of Cook Inlet beluga whales found in the Cook Inlet of Alaska is one...protection actions on the Cook Inlet beluga whale, such as population increases, are...

2012-02-07

408

Distribution and Abundance of Larval Fishes at Two North Carolina Inlets  

NASA Astrophysics Data System (ADS)

Two major barrier island inlets that connect Pamlico Sound with the Atlantic Ocean were quantitatively sampled for larvae at new moon monthly intervals during 1988-89. Simultaneous tows of bottom and surface 1 m, 500 micron mesh nets were made day and night at single stations inside of Oregon Inlet and Ocracoke Inlet. Oregon Inlet, located in a more temperate marine province, was expected to have a different taxonomic community than Ocracoke Inlet, but, of 77 taxa collected from both inlets, 54 occurred at both inlets. Clupeoids and sciaenids were the dominant taxa in both inlets. At Oregon Inlet the lowest abundance of larvae occurred in February and the highest occurred in late August, whereas at Ocracoke Inlet, November and June were the lowest and highest months of larval abundance. At Oregon Inlet, 63% of the total number of larvae were caught near the bottom, but at Ocracoke Inlet, only 38% were caught near the bottom. Atlantic menhaden, Brevoortia tyrannus, were 40 times more abundant at the surface than at the bottom at Ocracoke Inlet. Most larvae were caught at night at both inlets. The times of occurrence and peak abundance for most species did not appear linked between inlets. Twenty-one species were significantly different in mean length between the two inlets.

Hettler, W. F.; Barker, D. L.

1993-08-01

409

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

410

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

411

Nuclear criticality safety assessment of the proposed CFC replacement coolants  

SciTech Connect

The neutron multiplication characteristics of refrigerant-114 (R-114) and proposed replacement coolants perfluorobutane (C{sub 4}F{sub 10}) and cycloperfluorobutane C{sub 4}F{sub 8}) have been compared by evaluating the infinite media multiplication factors of UF{sub 6}/H/coolant systems and by replacement calculations considering a 10-MW freezer/sublimer. The results of these comparisons demonstrate that R-114 is a neutron absorber, due to its chlorine content, and that the alternative fluorocarbon coolants are neutron moderators. Estimates of critical spherical geometries considering mixtures of UF{sub 6}/HF/C{sub 4}F{sub 10} indicate that the flourocarbon-moderated systems are large compared with water-moderated systems. The freezer/sublimer calculations indicate that the alternative coolants are more reactive than R-114, but that the reactivity remains significantly below the condition of water in the tubes, which was a limiting condition. Based on these results, the alternative coolants appear to be acceptable; however, several follow-up tasks have been recommended, and additional evaluation will be required on an individual equipment basis.

Jordan, W.C.; Dyer, H.R.

1993-12-01

412

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

413

Characterization of a storm surge exposed arctic inlet: Shaktoolik, Alaska  

NASA Astrophysics Data System (ADS)

The Inupiaq community of Shaktoolik, in northwestern Alaska is constructed on a low-lying barrier spit located on Norton Sound. The inhabited portion of the spit is ~200m across and vulnerable to flooding from both the open water and lagoon sides during storm events. Previously modeled storm events estimate elevated sea surfaces reaching a maximum storm surge of 6.4m (21 feet) in the Norton Sound region. Historical storm events have been documented every few years in the region, usually occurring during the fall, but storm surge heights in Shaktoolik have never been recorded. An inlet is located at the northern terminus of the barrier spit, adjacent to the community, and provides access for fishing boats to and from the sheltered lagoon. This research focuses on the responses of Shaktoolik's inlet to storm surge and subsequent flooding of the spit. Fieldwork conducted in July 2011 focused on mapping the on land and nearshore coastal morphology of the barrier system. Prior to this, limited baseline data about the Shaktoolik coastal zone was available. The research goals for this project are to understand the morphodynamics of the inlet and surrounding coastal area and to analyze impacts on the inlet by storm surge events. This study is in support of a larger geohazard mapping project with the Alaska Department of Geological and Geophysical Surveys. Onshore, beach profiles and wrackline positions were surveyed, and grain size samples were collected north and south of the inlet. These data provide insight into the longshore sediment transport patterns, past flood levels, and the extent of possible flooding and inundation in the future. In the nearshore, bathymetric data, current velocity measurements, and suspended and bedload sediment samples were obtained seaward of the spit, in the inlet, and within the lagoon. Nearshore measurements characterize the inlet channel depths and composition, and locate areas of sediment deposition. In addition, three months of fall seasonal water levels were collected hourly on the lagoon side of the inlet in order to capture tide ranges and storm surge heights. Further analysis will include historical storm surge flooding estimates for Shaktoolik, water height ranges for storm events, and inlet current velocities and discharge rates.

Ohman, K. A.; Erikson, L. H.; Kinsman, N.

2011-12-01

414

Total-Pressure Distortion and Recovery of Supersonic Nose Inlet with Conical Centerbody in Subsonic Icing Conditions  

NASA Technical Reports Server (NTRS)

Ice was formed on a full-scale unheated supersonic nose inlet in the NACA Lewis icing tunnel to determine its effect on compressor-face total-pressure distortion and recovery.Inlet angle of attack was varied from 0degrees to 12 degrees, free-stream Mach number from 0.17 to 0.28, and compressor-face Mach number from 0.10 to 0.47. Icing-cloud liquid-water content was varied from 0.65 to 1.8 grams per cubic meter at free-stream static air temperatures of 15 degrees and 0 degrees F. The addition of ice to the inlet components increased total-pressure-distortion levels and decreased recovery values compared withclear0air results, the losses increasing with time in ice. The combination of glaze ice, high corrected weight flow, and high angle of attack yielded the highest levels of distortion and lowest values of recovery. The general character of compressor-face distortion with an iced inlet was the same as that for the clean inlet, the total-pressure gradients being predominantly radial, with circumferential gradients occurring at angle of attack. At zero angle of attack, free-stream Mach number of 0.27, and a constant corrected weight flow of 150 pounds per second (compressor-face Mach number of 0.43), compressor-face total-pressure-distortion level increased from about 6 percent in clear air to 12 percent after 21 minutes of heavy glaze icing; concurrently, total-pressure recovery decreased from about 0.98 to 0.945. For the same operating conditions but with the inlet at 12 deg angle of attack, a change in distortion level occurred from about 9 percent in clear air to 14 percent after 2-1/4 minutes of icing, with a decrease in recovery from about 0.97 to 0.94.

Gelder, Thomas F

1957-01-01

415

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

416

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

417

Design and Analysis Tool for External-Compression Supersonic Inlets  

NASA Technical Reports Server (NTRS)

A computational tool named SUPIN has been developed to design and analyze external-compression supersonic inlets for aircraft at cruise speeds from Mach 1.6 to 2.0. The inlet types available include the axisymmetric outward-turning, two-dimensional single-duct, two-dimensional bifurcated-duct, and streamline-traced Busemann inlets. The aerodynamic performance is characterized by the flow rates, total pressure recovery, and drag. The inlet flowfield is divided into parts to provide a framework for the geometry and aerodynamic modeling and the parts are defined in terms of geometric factors. The low-fidelity aerodynamic analysis and design methods are based on analytic, empirical, and numerical methods which provide for quick analysis. SUPIN provides inlet geometry in the form of coordinates and surface grids useable by grid generation methods for higher-fidelity computational fluid dynamics (CFD) analysis. SUPIN is demonstrated through a series of design studies and CFD analyses were performed to verify some of the analysis results.

Slater, John W.

2012-01-01

418

Passive acoustic monitoring of Cook Inlet beluga whales (Delphinapterus leucas).  

PubMed

The endangered beluga whale (Delphinapterus leucas) population in Cook Inlet, AK faces threats from a variety of anthropogenic factors, including coastal development, oil and gas exploration, vessel traffic, and military activities. To address existing gaps in understanding about the occurrence of belugas in Cook Inlet, a project was developed to use passive acoustic monitoring to document the year-round distribution of belugas, as well as killer whales (Orcinus orca), which prey on belugas. Beginning in June 2009, ten moorings were deployed throughout the Inlet and refurbished every two to eight months. Despite challenging conditions consisting of strong tidal currents carrying debris and seasonal ice cover, 83% of mooring deployments were successfully recovered. Noise from water flow, vessel traffic, and/or industrial activities was present at several sites, potentially masking some signals. However, belugas were successfully detected at multiple locations. Detections were relatively common in the upper inlet and less common or absent at middle and lower inlet locations. Killer whale signals were also recorded. Some seasonal variability in the occurrence of both belugas and killer whales was evident. PMID:23968047

Lammers, Marc O; Castellote, Manuel; Small, Robert J; Atkinson, Shannon; Jenniges, Justin; Rosinski, Anne; Oswald, Julie N; Garner, Chris

2013-09-01

419

Development and Transient Analysis of a Helical-coil Steam Generator for High Temperature Reactors  

SciTech Connect

A high temperature gas-cooled reactor (HTGR) is under development by the Next Generation Nuclear Plant (NGNP) Project at the Idaho National Laboratory (INL). Its design emphasizes electrical power production which may potentially be coupled with process heat for hydrogen production and other industrial applications. NGNP is considering a helical-coil steam generator for the primary heat transport loop heat exchanger based on its increased heat transfer and compactness when compared to other steam generators. The safety and reliability of the helical-coil steam generator is currently under evaluation as part of the development of NGNP. Transients, such as loss of coolant accidents (LOCA), are of interest in evaluating the safety of steam generators. In this study, a complete steam generator inlet pipe break (double ended pipe break) LOCA was simulated by an exponential loss of primary side pressure. For this analysis, a model of the helical-coil steam generator was developed using RELAP5-3D, an INL inhouse systems analysis code. The steam generator model behaved normally during the transient simulating the complete steam generator inlet pipe break LOCA. Further analysis is required to comprehensively evaluate the safety and reliability of the helical-coil steam generator design in the NGNP setting.

Nathan V. Hoffer; Nolan A. Anderson; Piyush Sabharwall

2011-08-01

420

Precise Measurement of Process Temperature Differences  

Microsoft Academic Search

Measurement of power in a nuclear reactor system is comparable to measurement of yield in a chemical plant or to measurement of throughput in a paper mill process. In most reactor systems power is determined by measurement of heat transferred to the coolant. In this study reactor coolant heat-rise was determined by the differential-temperature measuring circuitry of a power calculator

Kitchen

2003-01-01

421

Temperature  

NSDL National Science Digital Library

This topic in depth begins with the About Temperature (1) Web site, written by Beverly T. Lynds of Unidata, which is a program that works to enable university researchers and educators to acquire and use atmospheric and related data. The one-page site explains what temperature is, the development of thermometers, heat and thermodynamics, and other related topics. The second site is maintained by the University of Execter's Centre for Innovation in Mathematics Teaching. Actually an online tool called Conversion Calculator for Units of Temperature (2), the site allows users to type in any value, choose a significant figure, press "convert it," and get that value in Kelvin, Celsius, Fahrenheit, r'aumur, and rankine units. The next site is a lesson plan from AskEric.com entitled Temperature: Is it Hot or Cold? (3). Written for 2nd graders, the lesson demonstrates to how to read thermometers, determine their rise or fall, record temperatures, and take temperatures of various items. The fourth site, Surface Temperature Analysis (4), is presented by NASA's Goddard Institute for Space Studies. Here, visitors can view graphs, maps, animations, and station data of global surface temperatures. For example, the animation covers 12-month means from 1971 to 1999. The History Behind the Thermometer (5) Web site, from About.com, explores what a thermometer is, how it works, and how it came into being. The sixth site, entitled Science Shack (6) and offered by the BBC, answers the question, Why do we have two different temperature scales, Celsius and Fahrenheit? The site explains how to create your own thermometer like Galileo's, tells how it works, and why we use other types today. The next site is provided by National Oceanic and Atmospheric Administration (NOAA) and presents US State temperature extremes and drought information (7). Visitors can see all-time temperature maximums and minimums by state, monthly temperatures by state, and more. The last site is an all-inclusive temperature site called Temperature World (8). Everything from news, science, organizations, general interest, games, and more -- all related to temperature -- can be found here.

Brieske, Joel A.

422

Fracture mechanics evaluation for at typical PWR primary coolant pipe  

SciTech Connect

For the primary coolant piping of PWRs in Japan, cast duplex stainless steel which is excellent in terms of strength, corrosion resistance, and weldability has conventionally been used. The cast duplex stainless steel contains the ferrite phase in the austenite matrix and thermal aging after long term service is known to change its material characteristics. It is considered appropriate to apply the methodology of elastic plastic fracture mechanics for an evaluation of the integrity of the primary coolant piping after thermal aging. Therefore we evaluated the integrity of the primary coolant piping for an initial PWR plant in Japan by means of elastic plastic fracture mechanics. The evaluation results show that the crack will not grow into an unstable fracture and the integrity of the piping will be secured, even when such through wall crack length is assumed to equal the fatigue crack growth length for a service period of up to 60 years.

Tanaka, T. [Kansai Electric Power Company, Osaka (Japan); Shimizu, S.; Ogata, Y. [Mitsubishi Heavy Industries, Ltd., Kobe (Japan)

1997-04-01

423

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

424

Columbia's uninsulated water coolant lines in the payload bay  

NASA Technical Reports Server (NTRS)

Yesterday, NASA decided to postpone for 24-hours the launch of Columbia on mission STS-83 due to a requirement to add additional thermal insulation to water coolant lines in the orbiter's payload bay. The water coolant lines are seen here winding their way around the window on the left. Managers determined that the lines, which cool various electronics on the orbiter, were not properly insulated and could possibly freeze during Columbia's 16-days in space. Columbia's launch is now set for 2:00 p.m. EST on Friday, April 4, 1997.

1997-01-01

425

Isolated rotor noise due to inlet distortion or turbulence  

NASA Technical Reports Server (NTRS)

Theoretical formulation, analysis, and results are presented that are necessary to analyze quadrupole noise generated from a loaded, subsonic rotor because of its interaction with an inflow distortion or inlet turbulence. The ratio of quadrupole to dipole noise is largely a function of the axial Mach number, wheel tip Mach number, rotor solidity, and total pressure ratio across the rotor. It is relatively independent of the specific form of the inflow distortion or inlet turbulence. Comparisons with experimental data only succeed in predicting gross levels at a given speed and fail to predict the variation of noise at fixed speed with flow and pressure ratio. Likely sources of this discrepancy are discussed.

Mani, R.

1974-01-01

426

Advanced two-stage compressor program design of inlet stage  

NASA Technical Reports Server (NTRS)

The aerodynamic design of an inlet stage for a two-stage, 10/1 pressure ratio, 2 lb/sec flow rate compressor is discussed. Initially a performance comparison was conducted for an axial, mixed flow and centrifugal second stage. A modified mixed flow configuration with tandem rotors and tandem stators was selected for the inlet stage. The term conical flow compressor was coined to describe a particular type of mixed flow compressor configuration which utilizes axial flow type blading and an increase in radius to increase the work input potential. Design details of the conical flow compressor are described.

Bryce, C. A.; Paine, C. J.; Mccutcheon, A. R. S.; Tu, R. K.; Perrone, G. L.

1973-01-01

427

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

428

Operating method for gas turbine with variable inlet vanes  

SciTech Connect

A method is described of operating a gas turbine engine having a centrifugal compressor which is driven by a high-pressure turbine, and wherein the centrifugal compressor is the only compressor of the engine, comprising the steps of: positioning a variable inlet guide vane at an inlet air passage of the centrifugal compressor for adjusting the air flow rate through the engine; and changing the orientation of the guide vane while keeping the speed of rotation of the engine at a high level near its rated value to control the output of the engine by controlling the air flow rate through the engine.

Morishita, Susumu; Miyake, Yoshiyaki; Uchida, Seishi.

1993-07-06

429

High ethane recovery without inlet CO/sub 2/ removal  

SciTech Connect

The processes discussed in this work have been developed to achieve high levels of ethane recovery from inlet gas streams containing more CO/sub 2/ than can be tolerated by other current processes. These processes can reduce in size or eliminate entirely the CO/sub 2/ treating system required for the ethane recovery facility. The new processes also recover more ethane using less external compression horsepower, making them attractive even for inlet streams with little or no CO/sub 2/. Application of these designs results in less initial investment and lower operating expense.

Wilkinson, J.D.; Hudson, H.M.

1982-01-01

430

Water as a coolant of the city  

NASA Astrophysics Data System (ADS)

Rapid urbanization during the last century showed the necessity for understanding urban climate. Since already half of the world population lives in cities - and this number is predicted to increase in coming years and decades - making big urban areas comfortable places gains interest of the general public and policy makers, as well as scientists. It is well known fact that urban climate differs significantly from the climate of rural areas. This is caused by several factors such as lack of evaporation, anthropogenic heat, specific geometry of street canyons, etc. Magnitude of the effect of each of these factors is a widely discussed topic throughout the literature. One of the most important factors is a lack of evaporation and consequent change in the energy balance compared to rural areas. This research aims to reveal the effect of water in the city on the temperature and comfort of inhabitants. We hypothesize that water works as a cooling liquid of cities and the lack of it is the main reason for formation of so called urban heat island. We focus on two major ways water can be stored in cities; in a form of open water areas, and in plants and green areas in general. Open water buffers the temperature extremes in its surroundings, but also has a warming effect at night due to its higher heat capacity compared to buildings and pavements. Trees are then providing shading and transpirate significant amount of water. On the other hand, shading effect alone, as provided by for example mash, can increase the temperature in the area simply because it prevents ventilation. Human comfort is however not determined only by temperature; for example higher air humidity is known to lower comfort of inhabitants and therefore mitigate the cooling effect of evaporation. Understanding properly the different effects of urban climate, and the particular aspects that can influence it, is important for optimal urban design that provides pleasant living environment.

Solcerova, Anna; van de Ven, Frans; van de Giesen, Nick

2014-05-01

431

Temperature  

NSDL National Science Digital Library

This article discusses the relationship between temperature and heat and kinetic energy and it shows how to convert from degrees Fahrenheit to Centigrade. It also includes links to other resources, data, maps, and classroom activities.

2008-04-08

432

A passively-safe fusion reactor blanket with helium coolant and steel structure  

SciTech Connect

Helium is attractive for use as a fusion blanket coolant for a number of reasons. It is neutronically and chemically inert, nonmagnetic, and will not change phase during any off-normal or accident condition. A significant disadvantage of helium, however, is its low density and volumetric heat capacity. This disadvantage manifests itself most clearly during undercooling accident conditions such as a loss of coolant accident (LOCA) or a loss of flow accident (LOFA). This thesis describes a new helium-cooled tritium breeding blanket concept which performs significantly better during such accidents than current designs. The proposed blanket uses reduced-activation ferritic steel as a structural material and is designed for neutron wall loads exceeding 4 MW/m{sup 2}. The proposed geometry is based on the nested-shell concept developed by Wong, but some novel features are used to reduce the severity of the first wall temperature excursion. These features include the following: (1) A ``beryllium-joint`` concept is introduced, which allows solid beryllium slabs to be used as a thermal conduction path from the first wall to the cooler portions of the blanket. The joint concept allows for significant swelling of the beryllium (10 percent or more) without developing large stresses in the blanket structure. (2) Natural circulation of the coolant in the water-cooled shield is used to maintain shield temperatures below 100 degrees C, thus maintaining a heat sink close to the blanket during the accident. This ensures the long-term passive safety of the blanket.

Crosswait, K.M.

1994-04-01

433

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

434

Experimental investigation of water injection in subsonic diffuser of a conical inlet operation at free-stream Mach number of 2.5  

NASA Technical Reports Server (NTRS)

A spike-type nose inlet with sharp-lip cowl was investigated at a free-stream Mach number of 2.5 with water injection in its 16-inch diameter, 11-foot-long subsonic diffuser section. Inlet total temperature of exit with liquid-air ratios of about 0.04 with no apparent change in the critical pressure recovery. The observed temperature drops were less than the theoretically predicted values, and the amount of water evaporated was 35 to 50 percent less than that theoretically possible.

Beke, Andrew

1957-01-01

435

33 CFR 159.119 - Operability test; temperature range.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Operability test; temperature range. 159.119 Section 159...Testing § 159.119 Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating...

2014-07-01

436

33 CFR 159.119 - Operability test; temperature range.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Operability test; temperature range. 159.119 Section 159...Testing § 159.119 Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating...

2010-07-01

437

33 CFR 159.119 - Operability test; temperature range.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Operability test; temperature range. 159.119 Section 159...Testing § 159.119 Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating...

2013-07-01

438

33 CFR 159.119 - Operability test; temperature range.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Operability test; temperature range. 159.119 Section 159...Testing § 159.119 Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating...

2012-07-01

439

33 CFR 159.119 - Operability test; temperature range.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Operability test; temperature range. 159.119 Section 159...Testing § 159.119 Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating...

2011-07-01

440

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

441

Dynamics of a supersonic inlet-engine combination subjected to disturbances in fuel flow and inlet overboard bypass airflow  

NASA Technical Reports Server (NTRS)

An axisymmetric mixed-compression supersonic inlet and a single-spool turbojet engine were dynamically tested at Mach 2.5. The propulsion system was subjected to sweep-frequency sinusoidal disturbances of either inlet overboard bypass airflow. The disturbances were at a logarithmic sweep rate of 1 decade per minute. Dynamic responses were taken of signals throughout the propulsion system. Selected signals were reduced relative to the prime propulsion system parameters. The experimental data are presented in Bode plots. Most of the plots are for a frequency range of 1.0 to 50 hertz.

Wallhagen, R. E.; Paulovich, F. J.; Geyser, L. C.

1972-01-01

442

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

443

AUTOMOTIVE AND HEAVY-DUTY ENGINE COOLANT RECYCLING BY FILTRATION  

EPA Science Inventory

This evaluation addresses the product quality, waste reduction and economic issues involved in recycling automotive and heavy-duty engine coolants. he specific recycling units evaluated are a fleet-size unit and a portable unit, both based on the technology of chemical filtration...

444

AUTOMOTIVE AND HEAVY-DUTY ENGINE COOLANT RECYCLING BY DISTILLATION  

EPA Science Inventory

This evaluation addresses the product quality, waste reduction, and economic issues involved in recycling automotive and heavy-duty engine coolants for a facility such as the New Jersey Department of Transportation garage in Ewing, New Jersey. he specific recycling evaluated is b...

445

Glycol coolants improve heat transfer and corrosion control  

Microsoft Academic Search

Various liquids from plain water to exotic fluids have been used as coolants in large stationary diesel engines that drive compressors on natural gas pipeline distribution systems. Although water is an efficient heat transfer medium, its drawbacks of freezing at -32 F and boiling at 212 F seriously limit its usefulness. Special glycol-based heat transfer fluids are available and refined

Holfield

1995-01-01

446

Indian Point 2 Reactor Coolant Pump Seal evaluations  

Microsoft Academic Search

This report summarizes the findings on Westinghouse Reactor Coolant Pump Seal Performance at the Indian Point 2 Nuclear Power Station. The study was conducted under the joint sponsorship of Consolidated Edison of New York and the US Nuclear Regulatory Commission Office of Research. The conclusions and recommendations herein are based on the review of the plant operational and maintenance data

M. Subudhi; J. H. Taylor; J. H. Clinton; C. J. Czajkowski

1987-01-01

447

Technical note Coolant void worth in fast breeder reactors  

E-print Network

and minor-actinide burners K. Tucek *, J. Wallenius, W. Gudowski Department of Nuclear and Reactor Physics.elsevier.com/locate/anucene Annals of Nuclear Energy 31 (2004) 1783­1801 annals of NUCLEAR ENERGY #12;systems are usually conceived accidents. In this parametric study, we investigate coolant void worth for series of fast breeder

448

EVALUATION OF FILTRATION AND DISTILLATION METHODS FOR RECYCLING AUTOMOTIVE COOLANT.  

EPA Science Inventory

This evaluation addresses the product quality, waste reduction, and economic issues involved in recycling automotive and heavy-duty engine coolants at a New Jersey Department of Transportation garage. The specific recycling units evaluated are based on the technologies of filtrat...

449

INVESTIGATION OF CLEANER TECHNOLOGIES TO MINIMIZE AUTOMOTIVE COOLANT WASTES  

EPA Science Inventory

The U.S. Environmental Protection Agency in cooperation with the State of New Jersey evaluated chemical filtration and distillation technologies designed to recycle automotive and heavy-duty engine coolants. hese evaluations addressed the product quality, waste reduction, and eco...

450

April 7, 1998 Studies of Coolant Compatibility with Beryllium  

E-print Network

and to have thermal and flow properties similar to water. Attractive properties already known include that PF to have coolant and flow properties not much different from those of water and a radiation length longer physical properties between water and PF200. Property H 2 O PF200 Radiation Length (cm) 36:1 52 [1

Cinabro, David

451

Fuels, Lubricants, and Coolants. FOS: Fundamentals of Service.  

ERIC Educational Resources Information Center

This manual on fuels, lubricants, and coolants is one of a series of power mechanics tests and visual aids on automotive and off-the-road agricultural and construction equipment. Materials present basic information with illustrations for use by vocational students and teachers as well as shop servicemen and laymen. Focusing on fuels, the first of…

John Deere Co., Moline, IL.

452

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

453

DESIGN AND PERFORMANCE OF A LOW FLOW RATE INLET  

EPA Science Inventory

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

454

ERDC/CHLTR-09-19 Coastal Inlets Research Program  

E-print Network

ERDC/CHLTR-09-19 Coastal Inlets Research Program Evaluation of Proposed Channel on Circulation 2009 Evaluation of Proposed Channel on Circulation and Morphology Change at Kawaihae Harbor (non-storm) and a 6-month (winter storms) simulation with the CMS. The modeling analysis involved

US Army Corps of Engineers

455

HINCOF-1: a Code for Hail Ingestion in Engine Inlets  

NASA Technical Reports Server (NTRS)

One of the major concerns during hail ingestion into an engine is the resulting amount and space- and time-wise distribution of hail at the engine face for a given geometry of inlet and set of atmospheric and flight conditions. The appearance of hail in the capture streamtube is invariably random in space and time, with respect to size and momentum. During the motion of a hailstone through an inlet, a hailstone undergoes several processes, namely impact with other hailstones and material surfaces of the inlet and spinner, rolling and rebound following impact; heat and mass transfer; phase change; and shattering, the latter three due to friction and impact. Taking all of these factors into account, a numerical code, designated HINCOF-I, has been developed for determining the motion hailstones from the atmosphere, through an inlet, and up to the engine face. The numerical procedure is based on the Monte-Carlo method. The report presents a description of the code, along with several illustrative cases. The code can be utilized to relate the spinner geometry - conical or, more effective, elliptical - to the possible diversion of hail at the engine face into the bypass stream. The code is also useful for assessing the influence of various hail characteristics on the ingestion and distribution of hailstones over the engine face.

Gopalaswamy, N.; Murthy, S. N. B.

1995-01-01

456

Preliminary Investigation of a New Type of Supersonic Inlet  

NASA Technical Reports Server (NTRS)

A supersonic inlet with supersonic deceleration of the flow entirely outside of the inlet is considered. A particular arrangement with fixed geometry having a central body with a circular annular intake is analyzed, and it is shown theoretically that this arrangement gives high pressure recovery for a large range of Mach number and mass flow and therefore is practical for use on supersonic airplanes and missiles. For some Mach numbers the drag coefficient for this type of inlet is larger than the drag coefficient for the type of inlet with supersonic compression entirely inside, but the pressure recovery is larger for all flight conditions. The differences in drag can be eliminated for the design Mach number. Experimental results confirm the results of the theoretical analysis and show that pressure recoveries of 95 percent for Mach numbers of 1.33 and 1.52, 92 percent for a Mach number of 1.72, and 86 percent for a Mach number oof 2.10 are possible with the configurations considered. If the mass flow decreases, the total drag coefficient increases gradually and the pressure recovery does not change appreciably.

Ferri, Antonio; Nucci, Louis M

1946-01-01

457

STUDIES OF CIRCULATION AND PRIMARY PRODUCTION IN DEEP INLET ENVIRONMENTS  

EPA Science Inventory

This report summarizes the results of a three-year grant from the U.S. Environmental Protection Agency to investigate various aspects of circulation dynamics and primary production in a deep inlet environment. Throughout the course of the research, special attention has been give...

458

Muir and Riggs Glaciers, Muir Inlet, Alaska - 1950  

USGS Multimedia Gallery

This, the first of two repeat photographs, documents significant changes that have occurred during the nine years between photographs A and B. Although Muir Glacier has retreated more than 3 kilometers and thinned more than 100 meters, exposing Muir Inlet, it remains connected with tributary Riggs G...

459

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

460

The deglaciation of Clyde Inlet, northeastern Baffin Island, Arctic Canada  

E-print Network

; Laurentide; Ice Sheet; Baffin Island; cosmogenic exposure dating; radiocarbon dating. Introduction (LIS) in arctic fiord landscapes can now be