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1

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

2

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 atm and a 0.06 coolant flow ratio could permit a turbine blade inlet gas temperature of over 1900 K. This is more than 150 K greater than similar superalloy blades.

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

1978-01-01

3

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

4

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

Microsoft Academic Search

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

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

2008-01-01

5

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

6

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

7

Ultra-lean combustion at high inlet temperatures  

NASA Technical Reports Server (NTRS)

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

Anderson, D. N.

1981-01-01

8

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

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

Effects of fan inlet temperature disturbances on the stability of a turbofan engine  

NASA Technical Reports Server (NTRS)

The effects of steady-state and time-dependent fan inlet total temperature disturbances on the stability of a TF30-P-3 turbofan engine were determined. Disturbances were induced by a gaseous-hydrogen-fueled burner system installed upstream of the fan inlet. Data were obtained at a fan inlet Reynolds number index of 0.50 and at a low-pressure-rotor corrected speed of 90 percent of military speed. All tests were conducted with a 90 deg extent of the fan inlet circumference exposed to above-average temperatures.

Abdelwahab, M.

1981-01-01

11

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

12

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

13

Compatibility Issues for a High Temperature Dual Coolant Blanket  

SciTech Connect

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

Pint, Bruce A [ORNL

2007-01-01

14

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

NASA Astrophysics Data System (ADS)

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

Maqsood, Omar Shahzada

15

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

16

Predicted inlet gas temperatures for tungsten fiber reinforced superalloy turbine blades  

NASA Technical Reports Server (NTRS)

A procedure is presented for predicting the magnitude of the turbine inlet gas temperatures potentially achievable using first generation tungsten fiber reinforced superalloys (TFRS) turbine blades. Both uncoated blades and blades with thermal barrier coatings are considered. The thermal conductivities of two representative TFRS were measured over a range of temperatures. The results show that cooled TFRS blades may allow significantly higher gas temperatures than are possible with superalloy blades. For one design, the difference is about 150-200 K.

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

1978-01-01

17

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

NASA Astrophysics Data System (ADS)

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

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

2012-09-01

18

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

19

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

20

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

Microsoft Academic Search

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

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

2011-01-01

21

Effects of Coolant Temperature Changes on Reactivity for Various Coolants in a Liquid Salt Cooled Very High Temperature Reactor (LS-VHTR)  

SciTech Connect

The purpose of this study is to perform an investigation into the relative merit of various salts and salt compounds being considered for use as coolants in the liquid salt cooled very high temperature reactor platform (LS-VHTR). Most of the non-nuclear properties necessary to evaluate these salts are known, but the neutronic characteristics important to reactor core design are still in need of a more extensive examination. This report provides a two-fold approach to further this investigation. First, a list of qualifying salts is assembled based upon acceptable non-nuclear properties. Second, the effect on system reactivity for a secondary system transient or an off-normal or accident condition is examined for each of these salt choices. The specific incident to be investigated is an increase in primary coolant temperature beyond normal operating parameters. In order to perform the relative merit comparison of each candidate salt, the System Temperature Coefficient of Reactivity is calculated for each candidate salt at various state points throughout the core burn history. (author)

Casino, William A. Jr. [AREVA - Framatome ANP, 3315 Old Forest Road OF-15, P.O. Box 10935, Lynchburg, VA 24506-0935 (United States)

2006-07-01

22

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

23

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

24

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

25

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

26

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

27

On the dependence of the noise amplitude on the correlation length of inlet temperature fluctuations in PWRs  

E-print Network

On the dependence of the noise amplitude on the correlation length of inlet temperature University of Technology, Department of Nuclear Engineering, SE-412 96 Göteborg, Sweden b CEA, DEN, Cadarache effect Noise amplitude Moderator temperature fluctuation PWRs a b s t r a c t The dependence

Demazière, Christophe

28

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

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

29

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

30

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

31

The Effect of Inlet Pressure and Temperature on the Efficiency of a Single-stage Impulse Turbine Having an 11.0-inch Pitch-line Diameter Wheel  

NASA Technical Reports Server (NTRS)

Efficiency tests have been conducted on a single-stage impulse engine having an 11-inch pitch-line diameter wheel with inserted buckets and a fabricated nozzle diaphragm. The tests were made to determine the effect of inlet pressure, Inlet temperature, speed, and pressure ratio on the turbine efficiency. An analysis is presented that relates the effect of inlet pressure and temperature to the Reynolds number of the flow. The agreement between the analysis and the experimental data indicates that the changes in turbine efficiency with Inlet pressure and temperature may be principally a Reynolds number effect.

Gabriel, David S.; Carmen, Robert L.; Trautwein, Elmer E

1945-01-01

32

Convective heat transfer studies at high temperatures with pressure gradient for inlet flow Mach number of 0.45  

NASA Technical Reports Server (NTRS)

Heat transfer measurements were determined for a flat plate with and without pressure gradient for various free stream temperatures, wall temperature ratios, and Reynolds numbers for an inlet flow Mach number of 0.45, which is a representative inlet Mach number for gas turbine rotor blades. A shock tube generated the high temperature and pressure air flow, and a variable geometry test section was used to produce inlet flow Mach number of 0.45 and accelerate the flow over the plate to sonic velocity. Thin-film platinum heat gages recorded the local heat flux for laminar, transition, and turbulent boundary layers. The free stream temperatures varied from 611 R (339 K) to 3840 R (2133 K) for a T(w)/T(r,g) temperature ratio of 0.87 to 0.14. The Reynolds number over the heat gages varied from 3000 to 690,000. The experimental heat transfer data were correlated with laminar and turbulent boundary layer theories for the range of temperatures and Reynolds numbers and the transition phenomenon was examined.

Pedrosa, A. C. F.; Nagamatsu, H. T.; Hinckel, J. A.

1984-01-01

33

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

Microsoft Academic Search

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

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

2011-01-01

34

Effect of seasonal changes in use patterns and cold inlet water temperature on water-heating loads  

SciTech Connect

This paper presents long-term test data obtained in 20 commercial buildings and 16 residential sites. The information illustrates the effects of variations in hot water load determinants and the effect on energy use. It also is useful as a supplement to the load profiles presented in the ASHRAE Handbooks and other design references. The commercial facilities include supermarkets, fast-food restaurants, full-service restaurants, commercial kitchens, a motel, a nursing home, a hospital, a bakery, and laundry facilities. The residential sites ere selected to provide test sites with higher-than-average hot water use. They include 13 single-family detached residences, one 14-unit apartment building, and two apartment laundries. Test data are available at measurement intervals of 1 minute for the residential sites and 15 minutes for the commercial sites. Summary data in tabular and graphical form are presented for average daily volumetric hot water use and cold inlet water temperature. Measured cold inlet water temperature and volumetric hot water use figures are compared to values typically used for design and analysis. Conclusions are offered regarding the effect of cold water inlet temperature and variations in hot water use on water-heating load and energy use. Recommendations for the use of the information presented in water-heating system design, performance optimization, and performance analysis conclude the paper.

Abrams, D.W.; Shedd, A.C. [D.W. Abrams, P.E. and Associates, Atlanta, GA (United States)

1996-11-01

35

Inlet technology  

NASA Technical Reports Server (NTRS)

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

Kutschenreuter, Paul

1992-01-01

36

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

37

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

38

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

39

Development of a coolant channel helium and nitrogen gas ratio sensor for a high temperature gas reactor  

SciTech Connect

To measure the changing gas composition of the coolant during a postulated High Temperature Gas Reactor (HTGR) accident, an instrument is needed. This instrument must be compact enough to measure the ratio of the coolant versus the break gas in an individual coolant channel. This instrument must minimally impact the fluid flow and provide for non-direct signal routing to allow minimal disturbance to adjacent channels. The instrument must have a flexible geometry to allow for the measurement of larger volumes such as in the upper or lower plenum of a HTGR. The instrument must be capable of accurately functioning through the full operating temperature and pressure of a HTGR. This instrument is not commercially available, but a literature survey has shown that building off of the present work on Capacitance Sensors and Cross-Capacitors will provide a basis for the development of the desired instrument. One difficulty in developing and instrument to operate at HTGR temperatures is acquiring an electrical conductor that will not melt at 1600 deg. C. This requirement limits the material selection to high temperature ceramics, graphite, and exotic metals. An additional concern for the instrument is properly accounting for the thermal expansion of both the sensing components and the gas being measured. This work covers the basic instrument overview with a thorough discussion of the associated uncertainty in making these measurements. (authors)

Cadell, S. R.; Woods, B. G. [Oregon State Univ., 116 Radiation Center, Corvallis, OR 97331 (United States)

2012-07-01

40

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

NASA Technical Reports Server (NTRS)

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

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

1947-01-01

41

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

42

Navier-Stokes analyses of the redistribution of inlet temperature distortions in a turbine  

NASA Technical Reports Server (NTRS)

The flow exiting the combustor and entering the turbine of a gas turbine engine is known to contain both spatial and temporal variations in total temperature. Although historically it has been presumed that the turbine rotor responded to the average temperature, recent experimental evidence has demonstrated that the rotor actually separated the hotter and cooler streams of fluid so that the hotter fluid migrated toward the pressure surface and the cooler fluid migrated toward the suction surface. In the present study a time-accurate, two-dimensional, thin-layer, Navier-Stokes analysis of a turbine stage was used to analyze this phenomenon. The rough qualitative agreement between the measured and the computed results indicated that the analysis had successfully captured many of the important features of the flow.

Rai, Man Mohan; Dring, Robert P.

1987-01-01

43

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

44

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

45

Spontaneous ignition in afterburner segment tests at an inlet temperature of 1240 K and a pressure of 1 atmosphere with ASTM jet-A fuel  

NASA Technical Reports Server (NTRS)

A brief testing program was undertaken to determine if spontaneous ignition and stable combustion could be obtained in a jet engine afterburning operating with an inlet temperature of 1240 K and a pressure of 1 atmosphere with ASTM Jet-A fuel. Spontaneous ignition with 100-percent combustion efficiency and stable burning was obtained using water-cooled fuel spraybars as flameholders.

Schultz, D. F.; Branstetter, J. R.

1973-01-01

46

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

NASA Technical Reports Server (NTRS)

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

Meitner, P. L.

1978-01-01

47

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

48

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

49

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

NASA Technical Reports Server (NTRS)

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

Povolny, John H.; Bogdan, Louis J.

1947-01-01

50

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

NASA Astrophysics Data System (ADS)

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

Takei, Toshitaka; Saito, Kiyoshi; Kawai, Sunao

51

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

SciTech Connect

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

52

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

53

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

54

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

55

TACT1- TRANSIENT THERMAL ANALYSIS OF A COOLED TURBINE BLADE OR VANE EQUIPPED WITH A COOLANT INSERT  

NASA Technical Reports Server (NTRS)

As turbine-engine core operating conditions become more severe, designers must develop more effective means of cooling blades and vanes. In order to design reliable, cooled turbine blades, advanced transient thermal calculation techniques are required. The TACT1 computer program was developed to perform transient and steady-state heat-transfer and coolant-flow analyses for cooled blades, given the outside hot-gas boundary condition, the coolant inlet conditions, the geometry of the blade shell, and the cooling configuration. TACT1 can analyze turbine blades, or vanes, equipped with a central coolant-plenum insert from which coolant-air impinges on the inner surface of the blade shell. Coolant-side heat-transfer coefficients are calculated with the heat transfer mode at each station being user specified as either impingement with crossflow, forced convection channel flow, or forced convection over pin fins. A limited capability to handle film cooling is also available in the program. The TACT1 program solves for the blade temperature distribution using a transient energy equation for each node. The nodal energy balances are linearized, one-dimensional, heat-conduction equations which are applied at the wall-outer-surface node, at the junction of the cladding and the metal node, and at the wall-inner-surface node. At the mid-metal node a linear, three-dimensional, heat-conduction equation is used. Similarly, the coolant pressure distribution is determined by solving the set of transfer momentum equations for the one-dimensional flow between adjacent fluid nodes. In the coolant channel, energy and momentum equations for one-dimensional compressible flow, including friction and heat transfer, are used for the elemental channel length between two coolant nodes. The TACT1 program first obtains a steady-state solution using iterative calculations to obtain convergence of stable temperatures, pressures, coolant-flow split, and overall coolant mass balance. Transient calculations are based on the steady-state solutions obtained. Input to the TACT1 program includes a geometrical description of the blade and insert, the nodal spacing to be used, and the boundary conditions describing the outside hot-gas and the coolant-inlet conditions. The program output includes the value of nodal temperatures and pressures at each iteration. The final solution output includes the temperature at each coolant node, and the coolant flow rates and Reynolds numbers. This program is written in FORTRAN IV for batch execution and has been implemented on an IBM 360 computer with a central memory requirement of approximately 480K of 8 bit bytes. The TACT1 program was developed in 1978.

Gaugler, R. E.

1994-01-01

56

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

57

COASTAL INLET BANK EROSION  

Microsoft Academic Search

Much focus is placed on beach erosion on the open coast. However, coastal processes often occur on sandy shorelines interior to inlets that can lead to severe erosion. These shorelines lie adjacent to coastal inlets and extend around the inlet from the ocean to bay. In particular, an examination of coastal inlets with jetties or terminal groins that are connected

William C. Seabergh

2001-01-01

58

Compressor inlet guide vanes  

SciTech Connect

Guide vanes are the object of renewed interest because they can reduce power consumption 4 to 9 percent, depending on ambient conditions. Guide vanes function to impart a varying degree of whirl to air entering the compressor inlet in response to signals from the compressor. This induced rotation of the air, in the same direction the impeller turns, reduces the amount of work required to produce the same air discharge conditions. The net result is a lowering of power requirements at the compressor inlet. Inlet guide vanes offer dual benefits - decreased power consumption or increased capacity (over throttling at the same power consumption) - allowing compressors to be operated more cheaply or more efficiently. At 50 F average temperature, a 1000 hp compressor running continually for 1 year to 100 percent design flow would save an average of 42 hp. At 4.5 cent/kWh, this saving amounts of $11,280 per year. The initial cost of the guide vane assembly for a unit of this size is $5000. Thus, the payback period for the initial investment is less than 6 months.

Ledder, H.

1981-12-10

59

Probability distributions of peak-clad temperature and cladding oxidation thickness in loss-of-coolant accidents for a typical boiling water reactor. [MOXY-EM calculations  

Microsoft Academic Search

The probability distributions of the peak-clad temperature (PCT) and of the maximum cladding oxidation thickness supposed to occur in the hypothetical loss-of-coolant accidents (LOCAs) for a typical boiling water reactor (BWR) are studied by a computer-simulated experiment, using the computer program MOXY-EM, one of the fuel heatup analysis codes for a BWR. To reduce the numbers of the computer runs,

T. Shimooke; K. Matsumoto

1977-01-01

60

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

61

Thermal stratification potential in rocket engine coolant channels  

NASA Technical Reports Server (NTRS)

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

Kacynski, Kenneth J.

1992-01-01

62

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

63

Turbomachine injection nozzle including a coolant delivery system  

DOEpatents

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

Zuo, Baifang (Simpsonville, SC)

2012-02-14

64

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

65

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

66

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

NASA Technical Reports Server (NTRS)

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

Tacina, R. R.

1983-01-01

67

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

68

Exploratory Investigation of Transpiration Cooling of a 40 deg Double Wedge using Nitrogen and Helium as Coolants at Stagnation Temperatures from 1,295 deg F to 2,910 deg F  

NASA Technical Reports Server (NTRS)

An investigation of transpiration cooling has been conducted in the preflight jet of the Langley Pilotless Aircraft Research Station at Wallops Island, Va. The model consisted of a double wedge of 40 deg included angle having a porous stainless-steel specimen inserted flush with the top surface of the wedge. The tests were conducted at a free-stream Mach number of 2.0 for stagnation temperatures ranging from 1,295 F to 2,910 F. Nitrogen and helium were used as coolants and tests were conducted for values ranging from approximately 0.03 to 0.30 percent of the local weight flow rate. The data for both the nitrogen and helium coolants indicated greater cooling effectiveness than that predicted by theory and were in good agreement with the results for an 8 deg cone tested at a stagnation temperature of 600 F. The results indicate that the helium coolant, for the same amount of heat-transfer reduction, requires only about one-fourth to one-fifth the coolant flow weight as the nitrogen coolant.

Rashis, Bernard

1961-01-01

69

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

70

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

71

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

72

Experimental investigation of coolant-flow characteristics of a sintered porous turbine blade  

NASA Technical Reports Server (NTRS)

Local cooling-air flow rates through the walls of a sintered porous-metal turbine blade were measured at room temperature for a range of pressure drops. In order to check the validity of the correlation procedure, this procedure was used to correlate air-flow rates thorough two porous disks at temperatures up to 600 degrees F.245:00:Experimental investigation of coolant Data indicate the method permits room-temperature flow data to be used for heat-transfer work at elevated temperatures with reasonable accurach. Cooling-air flow distribution around the periphery of the test blade is presented for two internal cooling air pressures with the blade in a 1000 degrees Fahrenheit gas stream at a cascade-inlet Mach number of 0.45.

Bartoo, Edward R; Schafer, Louis J , Jr; Richards, Hadley T

1952-01-01

73

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

74

Surface cooling of scramjet engine inlets using heat pipe, transpiration, and film cooling  

SciTech Connect

This article reports the results of applying a finite-difference-based computational technique to the problem of predicting the transient thermal behavior of a scramjet engine inlet exposed to a typical hypersonic flight aerodynamic surface heating environment, including type IV shock interference heating. The leading-edge cooling model utilized incorporates liquid metal heat pipe cooling with surface transpiration and film cooling. Results include transient structural temperature distributions, aerodynamic heat inputs, and surface coolant distributions. It seems that these cooling techniques may be used to hold maximum skin temperatures to near acceptable values during the severe aerodynamic and type IV shock interference heating effects expected on the leading edge of a hypersonic aerospace vehicle scramjet engine. 15 refs.

Modlin, J.M.; Colwell, G.T. (U.S. Army, Strategic Defense Command, Huntsville, AL (United States) Georgia Institute of Technology, Atlanta (United States))

1992-09-01

75

HANARO secondary coolant management.  

National Technical Information Service (NTIS)

In this report, the basic theory for management of water quality, environmental factors influencing to the coolant, chemicals and its usage for quality control of coolant are mentioned, and water balance including the loss rate by evaporation (34.3 m(sup ...

S. D. Kim

1998-01-01

76

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

77

Comparison of Aerosol Sampler Inlets  

Microsoft Academic Search

This field study compared aerosol collection by nominal 15 ?m inlets for low volume (1 m\\/hr) aerosol samplers. The inlets were designed at Texas A & M University (TAMU), Colorado State University (CSU), the University of Minnesota–Lawrence Berkeley Laboratory (UMLBL), and the Aerovironment Corporation (AERO). The TAMU inlet design is currently used on most commercial dichotomous samplers, and recent wind

R. W. Shaw Jr; R. K. Stevens; C. W. Lewis; James H. Chance

1982-01-01

78

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

79

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

80

Blade-to-coolant heat-transfer results and operating data from a natural-convection water-cooled single-stage turbine  

NASA Technical Reports Server (NTRS)

Blade-to-coolant heat-transfer data and operating data were obtained with a natural-convection water-cooled turbine over range of turbine speeds and inlet-gas temperatures. The convective coefficients were correlated by the general relation for natural-convection heat transfer. The turbine data were displaced from a theoretical equation for natural convection heat transfer in the turbulent region and from natural-convection data obtained with vertical cylinders and plates; possible disruption of natural convection circulation within the blade coolant passages was thus indicated. Comparison of non dimensional temperature-ratio parameters for the blade leading edge, midchord, and trailing edge indicated that the blade cooling effectiveness is greatest at the midchord and least at the trailing edge.

Diaguila, Anthony J; Freche, John C

1951-01-01

81

Analysis of the SSME HPOTP bearing inlet cavity  

NASA Technical Reports Server (NTRS)

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

Mcconnaughey, P. K.

1989-01-01

82

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

83

A Heated Tube Facility for Rocket Coolant Channel Research  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

84

A comparative study of the effect of inlet conditions on a free convection flow in a vertical channel  

SciTech Connect

This note discusses the influence of inlet conditions on the natural convection boundary layer flow within an asymmetrically heated vertical channel. Both uniform heat flux (UHF) and uniform surface temperature conditions (UST) are considered. Inlet conditions examined include a uniform velocity profile with/without inlet pressure defect and a parabolic velocity profile with/without inlet pressure defect. The inlet pressure defect is accounted by applying the Bernoulli equation at the inlet. Numerical results are compared with available experimental results to assess the sensitivity of the thermal performance parameters (local and overall average Nusselt numbers) to the change in inlet condition specifications.

Chappidi, P.R.; Eno, B.E. (Univ. of Central Florida, Orlando (USA))

1990-11-01

85

Design of bioaerosol sampling inlets  

E-print Network

of isokinetic sampling can be used to determine if a representative sample of aerosol arrives at the inlet plane of a sampling nozzle. Sampling is isokinetic when the inlet axis of the sampler, e.g., a thin-walled tube or probe, is aligned parallel... to the gas streamlines and the gas velocity at the probe entrance plane equals the free stream velocity approaching the inlet. However, due to the possibility of internal wall losses in the nozzle, the condition of isokineticity is no assurance...

Nene, Rohit Ravindra

2007-09-17

86

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

87

Subcooled freon-11 flow boiling in top-heated finned coolant channels with and without a twisted tape  

NASA Technical Reports Server (NTRS)

An experimental study was conducted in top-heated finned horizontal tubes to study the effect of enhancement devices on flow boiling heat transfer in coolant channels. The objectives are to examine the variations in both the mean and local (axial and circumferential) heat transfer coefficients for circular coolant channels with spiral finned walls and/or spiral fins with a twisted tape, and improve the data reduction technique of a previous investigator. The working fluid is freon-11 with an inlet temperature of 22.2 C (approximately 21 C subcooling). The coolant channel's exit pressure and mass velocity are 0.19 M Pa (absolute) and 0.21 Mg/sq. ms, respectively. Two tube configurations were examined; i.e., tubes had either 6.52 (small pitch) or 4.0 (large pitch) fins/cm of the circumferential length (26 and 16 fins, respectively). The large pitch fins were also examined with a twisted tape insert. The inside nominal diameter of the copper channels at the root of the fins was 1.0 cm. The results show that by adding enhancement devices, boiling occurs almost simultaneously at all axial locations. The case of spiral fins with large pitch resulted in larger mean (circumferentially averaged) heat transfer coefficients, h sub m, at all axial locations. Finally, when twisted tape is added to the tube with large-pitched fins, the power required for the onset of boiling is reduced at all axial and circumferential locations.

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

1989-01-01

88

Neuroblastoma of the thoracic inlet.  

PubMed

The case of a 5-month-old girl with a large neuroblastoma of the thoracic inlet, an unusual location for this tumor, is presented. The patient had marked airway compromise due to tumor compression, with extension of the mass through the thoracic inlet into the base of the neck, also incorporating the right subclavian artery. The highly unusual location of this tumor is presented, and challenging technical aspects of its management are discussed. PMID:2352091

Pelton, J J; Ratner, I A

1990-05-01

89

Analysis of the Reactor Cavity Cooling System for Very High Temperature Gas-cooled Reactors Using Computational Fluid Dynamics Tools  

E-print Network

at the standpipes outlet; TRISO Tri-isotopic, ceramic-coated-particle fuel; Tse temperature of the annulus external wall; TsI temperature of the inner tube; U velocity; U0 reference water velocity at the standpipes inlet; u* reference velocity... elements. The fuel blocks are composed of hexagonal columns of graphite with circular holes that run the full length of the column. The fueled holes contain fuel compact that contains Tri- isotopic (TRISO) particles, while the coolant holes align axially...

Frisani, Angelo

2011-08-08

90

Assessment of effects of Fort St. Vrain HTGR primary coolant on Alloy 800. Final report  

Microsoft Academic Search

A comprehensive review was conducted of primary helium coolant chemistry data, based on current and past operating histories of helium-cooled, high-temperature reactors (HTGRs), including the Fort St. Vrain (FSV) HTGR. A reference observed FSV reactor coolant environment was identified. Further, a slightly drier expected FSV coolant chemistry was predicted for reactor operation at 100% of full power. The expected environment

P. W. Trester; W. R. Johnson; M. T. Simnad; R. D. Burnette; D. I. Roberts

1982-01-01

91

Method for removing cesium from a nuclear reactor coolant  

DOEpatents

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

Colburn, Richard P. (Pasco, WA)

1986-01-01

92

Safety and environmental aspects of organic coolants for fusion facilities  

Microsoft Academic Search

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%).

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

1993-01-01

93

Energetic fuel-coolant interactions considering chemical reactions  

SciTech Connect

A propagation/expansion model developed for large scale vapor explosions was enhanced to consider the possibility of a chemical reaction between metallic fuel and the water coolant during an energetic fuel-coolant interaction (FCI). This lumped volume model, based on a fragmentation concept involving film collapse, coolant jet impingement and entrapment, predicts the correct qualitative trends for recent Sandia NPR experiments involving molten aluminum dropped into water, as a function of fuel composition, coolant temperature, ambient pressure, coolant/fuel mass ratio, and initial constraints. Chemical reactions between the molten metal and the water vapor in the surrounding film are considered and predicts aluminum ignition at 1,225 K compared to the empirically observed chemical assisted vapor explosion at 1,150 K.

Uludogan, A.; Corradini, M.L. [Univ. of Wisconsin, Madison, WI (United States)

1995-12-31

94

Oscillating-Coolant Heat Exchanger  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

95

Effects of gas flow rate, inlet concentration and temperature on biofiltration of volatile organic compounds in a peat-packed biofilter.  

PubMed

The effects of incoming gas concentration, empty bed residence time (EBRT), and column temperature on the removal efficiency of volatile organic compounds (isoprene, dimethyl sulfide, chloroform, benzene, trichloroethylene, toluene, m-xylene, o-xylene and styrene) were studied for 101 d in a biofilter comprising two glass columns (I.D. 5.0 cm x height 62 cm) packed with peat. At an EBRT of 3 min the removal efficiency increased up to 90% 34 d after start up at both 25 degrees C and 45 degrees C when the incoming gas concentration was raised stepwise to 65 g.m(-3). When the incoming gas concentration increased to 83 g.m(-3), the removal efficiency was 93% at 25 degrees C, but dropped to 74% at 45 degrees C. At an incoming gas concentration of 92 g.m(-3) and an EBRT of 1.5 min, the removal efficiencies were 91% and 94% at 25 degrees C and 32 degrees C, respectively. However, at 1 min of EBRT, the removal efficiencies decreased to 68% and 81% at 25 degrees C and 32 degrees C, respectively. The removal rate per unit time and per unit volume of the biofilter was proportional to the incoming gas rate up to 3483 g VOC.m(-3).h(-1). Further increase of the incoming gas rate lowered the removal rate as compared to that predicted by the proportionality. The maximum removal rate was 3977 g.m(-3).h(-1) at 32 degrees C. At an EBRT of 1.5 min, the removal efficiency was highest for isoprene (93%), and lowest for chloroform (84%). Aromatic compounds (benzene, toluene, and xylene) were removed by 93-94%. The cell concentration increased 100-fold from the initial value, and reached 1.12 x 10(8) cells.(g of dry peat)(-1). At 32 degrees C, 67% of the incoming VOC was removed in the first quarter of the column. PMID:16233182

Yoon, In-Kil; Park, Chang-Ho

2002-01-01

96

Performance study for inlet installations  

NASA Technical Reports Server (NTRS)

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

Bingaman, Donald C.

1992-01-01

97

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

98

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

99

Experimental transient turbine blade temperatures in a research engine for gas stream temperatures cycling between 1067 and 1567 k  

NASA Technical Reports Server (NTRS)

Experimental transient turbine blade temperatures were obtained from tests conducted on air-cooled blades in a research turbojet engine, cycling between cruise and idle conditions. Transient data were recorded by a high speed data acquisition system. Temperatures at the same phase of each transient cycle were repeatable between cycles to within 3.9 K (7 F). Turbine inlet pressures were repeatable between cycles to within 0.32 N/sq cm (0.47 psia). The tests were conducted at a gas stream temperature of 1567 K (2360 F) at cruise, and 1067 K (1460 F) at idle conditions. The corresponding gas stream pressures were about 26.2 and 22.4 N/sq cm (38 and 32.5 psia) respectively. The nominal coolant inlet temperature was about 811 K (1000 F).

Gauntner, D. J.; Yeh, F. C.

1975-01-01

100

Evaluation of the Long-Term Thermal Capability of a High-Temperature Insulation System Using Silicone Liquid as a Dielectric Coolant  

Microsoft Academic Search

The functional thermal evaluation of test transformers insulated with silicon fluid is described. Studies have shown that polydimethylsiloxane fluids maintain good electrical properties at elevated temperatures, but system evaluation is required to determine their capability in a transformer. A transformer test facility meeting the requirements of IEEE Standard 262 is described and was used for the accelerated thermal testing of

Louis N. Gifford; Tor Orbeck

1984-01-01

101

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

102

Coolant mixing in a PWR - de-boration transients, steam line breaks and emergency core cooling injection - experiments and analyses  

SciTech Connect

The reactor transient caused by a perturbation of boron concentration or coolant temperature at the inlet of a Pressurized Water Reactor (PWR) depends on the mixing inside the reactor pressure vessel. Initial steep gradients are partially lessened by turbulent mixing with coolant from the unaffected loops and with the water inventory of the reactor pressure vessel. Nevertheless the assumption of an ideal mixing in the downcomer and the lower plenum of the reactor leads to un-realistically small reactivity inserts. The uncertainties between ideal mixing and total absence of mixing are too large to be acceptable for safety analyses. In reality, a partial mixing takes place. For realistic predictions it is necessary to study the mixing within the three-dimensional flow field in the complicated geometry of a PWR. For this purpose a 1:5 scaled model (the ROCOM facility) of the German PWR KONVOI was built. Compared to other experiments, the emphasis was put on extensive measuring instrumentation and a maximum of flexibility of the facility to cover as much as possible different test scenarios. The use of special electrode-mesh sensors together with a salt tracer technique provided distributions of the disturbance within downcomer and core entrance with a high resolution in space and time. Especially the instrumentation of the downcomer gained valuable information about the mixing phenomena in detail. The obtained data was used to support code development and validation. Scenarios investigated are: (1) Steady-state flow in multiple coolant loops with a temperature or boron concentration perturbation in one of the running loops. (2) Transient flow situations with flow rates changing with time in one or more loops, such as pump start-up scenarios with deborated plugs in one of the loops or onset of natural circulation after boiling-condenser-mode operation. (3) Gravity driven flow caused by large density gradients, e.g. mixing of cold emergency core cooling water entering the RPV through the ECC injection into the cold leg. The experimental results show an incomplete mixing with typical concentration and temperature distributions at the core inlet. which strongly depend on the boundary conditions. CFD calculations were found to be in good agreement with the experiments. (authors)

Prasser, H.M.; Grunwald, G.; Hoehne, Th.; Kliem, S.; Rohde, U.; Weiss, F.P. [Forschungszentrum Rossendorf, Institute of Safety Research, P.O.B. 510119 D-01314 Dresden (Germany)

2002-07-01

103

Advantages of air conditioning and supercharging an LM6000 gas turbine inlet  

SciTech Connect

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

Kolp, D.A. [Kolp Engineering, Avon, CT (United States); Flye, W.M. [Stewart and Stevenson, Houston, TX (United States); Guidotti, H.A. [Energy Services, Inc., Framington, CT (United States)

1995-07-01

104

Coherent lidar solution for the HSCT supersonic engine inlet unstart problem  

Microsoft Academic Search

Atmospheric turbulence environments can adversely affect the operation of both commercial and military supersonic aircraft. Future aircraft designs, such as the High Speed Civil Transport will aim to alleviate the effects of supersonic engine inlet unstart. Fluctuations in air temperature, longitudinal and transverse velocity all can trigger inlet unstarts. With fore- knowledge of the turbulence, a feed-forward control system can

Rodney K. Bogue; Harold R. Bagley; David C. Soreide; David A. Bowdle

1995-01-01

105

Treatment of mixed waste coolant  

SciTech Connect

The primary processes used at Lawrence Livermore National Laboratory (LLNL) for treatment of radioactively contaminated machine coolants are industrial waste treatment and in situ carbon adsorption. These two processes simplify approaches to meetings the sanitary sewer discharge limits and subsequent Land Disposal REstriction criteria for hazardous and mixed wastes (40 CFR 268). Several relatively simple technologies are used in industrial water treatment. These technologies are considered {open_quotes}Best Demonstrated Available Technologies,{close_quotes} or BDAT, by the Environmental Protection Agency. The machine coolants are primarily aqueous and contain water soluble oil consisting of ethanol amine emulsifiers derived from fatty acids, both synthetic and natural. This emulsion carries away metal turnings from a part being machined on a lathe or other machining tool. When the coolant becomes spent, it contains chlorosolvents carried over from other cutting operations as well as a fair amount of tramp oil from machine bearings. This results in a mutiphasic aqueous waste that requires treatment of metal and organic contaminants. During treatment, any dissolved metals are oxidized with hydrogen peroxide. Once oxidized, these metals are flocculated with ferric sulfate and precipitated with sodium hydroxide, and then the precipitate is filtered through diatomaceous earth. The emulsion is broken up by acidifying the coolant. Solvents and oils are adsorbed using powdered carbon. This carbon is easily separated from the remaining coolant by vacuum filtration.

Kidd, S.; Bowers, J.S. [Lawrence Livermore National Lab., CA (United States)

1995-09-01

106

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

107

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

NASA Technical Reports Server (NTRS)

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

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

1986-01-01

108

Sensitivity studies of loss-of-coolant accidents in the Savannah River production reactors  

SciTech Connect

Loss-of-coolant accident (LOCA) analyses were completed using the Transient Reactor Analysis Code (TRAC) to support the U.S. Department of Energy efforts to restart the production reactors located at the Savannah River Site. The break location and pump operation after the LOCA were the parameters varied for these sensitivity studies. Three location of double-ended guillotine break were studied: plenum inlet, pump suction, and pump discharge. Three pump operation scenarios were also studied: continued operation of both ac and dc pumps, tripping of the ac motor at 2 s after the LOCA, and tripping of the ac motor at 200 s after the LOCA. The production reactors use low pressure and temperature heavy water as the process fluid. The reactor has a moderator tank that contains the fuel channels. Above the moderator tank is an upper plenum that distributes the heavy water to each fuel assembly. The heavy water flows down through the fuel channels and into the moderator tank. From the tank, the water is pumped back to the upper plenum through six loops. Each loop contains a pump and two heat exchangers. Four of the loops have an emergency core coolant system (ECCS) connection. This TRAC model has been benchmarked extensively against data taken in the actual reactors or in prototypical models of the components of the reactors. The calculations were completed using a version of TRAC-PF1/MOD 2 that was updated to include heavy water properties and other changes that are specific to the production reactors.

Edwards, J.N.; Motley, F.E.; Morgan, M.M.; Knight, T.D.; Fischer, S.R. (Los Alamos National Lab., NM (USA))

1990-01-01

109

Centrifugal pump inlet pressure site affects measurement.  

PubMed

During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length. PMID:20630918

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

2010-09-01

110

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

111

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

112

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

113

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

114

Interactions between an organic coolant and drops of molten lithium  

SciTech Connect

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

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

1994-11-01

115

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

SciTech Connect

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

116

Effect of combustor-inlet conditions on performance of an annular turbojet combustor  

NASA Technical Reports Server (NTRS)

The combustion performance, and particularly the phenomenon of altitude operational limits, was studied by operating the annular combustor of a turbojet engine over a range of conditions of air flow, inlet pressure, inlet temperature, and fuel flow. Information was obtained on the combustion efficiencies, the effect on combustion of inlet variables, the altitude operational limits with two different fuels, the pressure losses in the combustor, the temperature and velocity profiles at the combustor outlet, the extent of afterburning, the fuel-injection characteristics, and the condition of the combustor basket.

Childs, J Howard; Mccafferty, Richard J; Surine, Oakley W

1947-01-01

117

Multiple-Inlet/Single-Outlet Orifice Plate  

NASA Technical Reports Server (NTRS)

Orifice plate for control of flow has multiple slanted inlets leading to single outlet. Multiple-inlet/single-outlet orifice less susceptible to blockage than single hole drilled through plate perpendicular to its surface. Easily calibrated for various flow rates and fits in place of simple orifice plate with no other modifications.

Godown, Robert L.

1990-01-01

118

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

119

Computational modeling and validation for hypersonic inlets  

NASA Technical Reports Server (NTRS)

Hypersonic inlet research activity at NASA is reviewed. The basis is the experimental tests performed with three inlets: the NASA-Lewis Mach 5, the McDonnell Douglas Mach 12, and the NASA-Langley Mach 18. Both 3-D parabolized Navier-Stokes and Navier-Stokes codes were used to compute the flow within the three inlets. Modeling assumptions in the codes involve the turbulence model, the nature of the boundary layer, shock wave boundary layer interaction, and the flow spilled to the outside of the inlet. Use of the codes in conjunction with the experimental data are helping to develop a clearer knowledge of the inlet flow physics and to focus on the modeling improvements required in order to arrive at validated codes.

Povinelli, Louis A.

1990-01-01

120

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

121

Aerodynamic analysis of VTOL inlets and definition of a short, blowing-lip inlet  

NASA Technical Reports Server (NTRS)

The results indicated that, without boundary layer control, either a very long inlet or an inlet with a very high contraction ratio lip will be required to meet the stringent design requirements. It is shown that active boundary layer control is an effective means of preventing separation and that a significant reduction in inlet size can be achieved by removing only a small amount of bleed in the throat region of the inlet. A short, blowing-lip model was designed and fabricated. This model features an adjustable, blowing slot located near the hilite on the windward side of the inlet.

Syberg, J.; Jones, A. L.

1982-01-01

122

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

123

Fast acting inlet guide vanes  

SciTech Connect

A fast acting inlet guide vane (IGV) system was developed for the model Siemens V94.2 gas turbine (GT). This system enables the GT to perform larger and faster load changes in the case of electrical grid disturbances. Disturbances in electrical grids are caused by an unbalance between actual power generation and power consumption resulting in grid frequency deviations. In order to reduce such deviations, it is desirable for a GT (connected to the grid), to increase/reduce load as fast as required. This task is achieved by the fast responding IGV system: Basically, the occurring grid frequency deviation is monitored by the IGV system. Depending on this deviation, the compressor air mass flow is adapted to the changing fuel mass flow (which is set approximately proportional to the frequency deviation by the GT controller). The fast IGV actuator plays a main role in this dynamic response, allowing the vanes to open/close very fast. Tests performed on Poolbeg site (Ireland) proved safe and rapid load changes with a typical load ramp of 50 MW within 3 sec.

Minne, M.; Kull, R.

1998-07-01

124

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

125

Hydrodynamics and equilibrium of a multiple-inlet system  

Microsoft Academic Search

Although it is generally acknowledged that most multiple inlets are unstable and cannot coexist, there is evidence to suggest that such inlets can indeed be stable over decadal time scales. Multiple-inlet systems servicing a single embayment, in contrast to single-inlet systems, confer particular hydrodynamic characteristics such as the potential existence of residual discharges and currents between the inlets. This paper

A. Pacheco; Ó. Ferreira; J. J. Williams; E. Garel; A. Vila-Concejo; J. A. Dias

2010-01-01

126

NUMERICAL SIMULATIONS OF INVISCID AIRFLOWS IN RAMJET INLETS  

Microsoft Academic Search

The performances of three different ramjet inlets and an entire ramjet are numerically studied in this paper. The fluid is assumed to be inviscid. Inlet 1 is a SCRAMJET inlet and is chosen from the literature. Inlets 2 and 3 are instead designed based on the Oswatitsch principle. Inlets 2 and 3 produce a series of oblique shocks merging at

M. Akbarzadeh; M. J. Kermani

2009-01-01

127

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

NASA Astrophysics Data System (ADS)

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

128

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

NASA Astrophysics Data System (ADS)

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 seal and the classic venturi. Seal effectiveness appears strongly dependent on upstream losses and geometry configuration.

Hendricks, R. C.

129

Analysis of automobile radiator performance with ethylene glycol/water and propylene glycol/water coolants  

SciTech Connect

The heat transfer and hydraulic performance of the following coolants was examined in five automobile radiators in a wind tunnel: 100% water; 100% propylene glycol; 70/30 propylene glycol/water (volume); 50/50 propylene glycol/water (volume); 70/30 ethylene glycol/water (volume); 50/50 ethylene glycol water (volume). The results of these studies are presented to demonstrate the relative performance of these coolant mixtures in terms of heat transfer, coolant pressure drop and radiator effectiveness for a range of coolant and air flowrates. It is concluded that the most effective of the coolants in transferring heat in the test radiators was water, followed by 50/50 ethylene glycol/water, 50/50 propylene glycol/water, 70/30 ethylene glycol/water, 70/30 propylene glycol and, finally, 100% propylene glycol. There will be a negligible differences between the performance of a radiator using a 50/50 propylene glycol/water coolant and a 50/50 ethylene glycol/water coolant. It is estimated that, with 50/50 propylene glycol coolant replacing 50/50 ethylene glycol/water, the temperature of the coolant throughout the cooling loop will increase by approximately 5%. The effect that the flow regime (fully turbulent/transition/laminar) has upon the performance of a given radiator/coolant combination was found to be significant. The design of the coolant passages in radiators can affect the onset of fully turbulent flow in the coolant passages in a radiator.

Gollin, M. [ARCO Chemical Co., Newtown Square, NJ (United States); Bjork, D.

1996-12-31

130

Fuel-Coolant Interactions: Visualization and Mixing Measurements  

SciTech Connect

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

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

2002-08-01

131

Fuel-Coolant Interactions: Visualization and Mixing Measurements  

SciTech Connect

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

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

2002-08-15

132

Turbine Inlet Analysis of Injected Water Droplet Behavior  

NASA Astrophysics Data System (ADS)

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

Hargrave, Kevin

133

Computational analysis of ramjet engine inlet interaction  

NASA Technical Reports Server (NTRS)

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

Duncan, Beverly; Thomas, Scott

1992-01-01

134

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

135

New PM10 Inlet Design and Evaluation  

Microsoft Academic Search

A new PM10 inlet for a beta-gauge sampler was designed based on the particle cup impactor concept. The performance of the inlet was evaluated at near-zero wind velocity in the test chamber and at the wind velocities of 2 and 8 km\\/hr in the wind tunnel. The performance indicated that particles with aerodynamic diameters of 10 ?m or larger were

H. T. Kim; Y. J. Kim; K. W. Lee

1998-01-01

136

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

137

A Helical Coolant Channel Design for the Solid Wall Blanket  

SciTech Connect

A helical coolant channel scheme is proposed for the APEX solid wall blanket module. The self-coolant breeder in this system is FLIBE (LiF)2(BeF2). The structural material is the nanocomposited alloy 12YWT. The neutron multiplier used in the current design is either stationary or slow moving liquid lead. The purpose of this study is to design a blanket that can handle a high wall loading (5 MW/m{sup 2}). In the mean time the design provides means to attain the maximum possible blanket outlet temperature and meet all engineering limits on temperature of structural material and liquids. An important issue for such a design is to optimize the system for minimum pressure loss. For advanced ferritic steel (12YWT) an upper temperature limit of 800 deg. C is expected, and a limit of 700 deg. C at the steel/FLIBE interface is recommended.The blanket module is composed of two main continuous routes. The first route is three helical rectangular channels side-by-side that surround a central box. The helical channels are fed from the bottom and exit at the top to feed the central channels in the central box. The coolant helical channels have a cross sectional area with a length of about 10 cm and a width that changes according to the position around the central box. For instance: the width of the coolant channels facing the plasma is the narrowest while it is the widest in the back (farthest from the plasma).In this design the coolant runs around the central box for only 5 turns to cover the total height of the first wall (6.8 m). The design is optimized with the FW channel width as a parameter with the heat transfer requirements at the first wall as the constraints.

Mogahed, E.A. [University of Wisconsin-Madison (United States)

2003-07-15

138

Assessment of Effects of Fort St. Vrain HTGR Primary Coolant on Alloy 800. Final Report.  

National Technical Information Service (NTIS)

A comprehensive review was conducted of primary helium coolant chemistry data, based on current and past operating histories of helium-cooled, high-temperature reactors (HTGRs), including the Fort St. Vrain (FSV) HTGR. A reference observed FSV reactor coo...

D. I. Roberts, M. T. Simnad, P. W. Trester, R. D. Burnette, W. R. Johnson

1982-01-01

139

Organic coolant for ARIES-III  

Microsoft Academic Search

ARIES-III is a D-Heâ reactor design study. It is found that the organic coolant is well suited for the D-Heâ reactor. This paper discusses the unique features of the D-Heâ reactor, and the reason that the organic coolant is compatible with those features. The problems associated with the organic coolant are also discussed. 8 refs., 2 figs., 6 tabs.

D. K. Sze; I. Sviatoslavsky; M. Sawan; P. Gierszewski; R. Hollies; S. Sharafat; S. Herring

1991-01-01

140

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

141

A computational study of icing effects on the performance of an S-duct inlet  

NASA Astrophysics Data System (ADS)

The performance of a diffusing S-duct inlet (M2129) is computationally studied for the effects of inlet icing. Different ice accretion shapes, predicted by numerical analysis in the literature reviewed, are simulated on the inlet lip. Two commercial codes, FLUENT and STAR-CCM+ are used for the steady- and unsteady-state computations. The shear-stress transport (SST) kappa-o turbulence model and large eddy simulation (LES) turbulence model are applied in the computations. The glaze ice shape, which is characterized by intrusive horns, degrades inlet performance, while the effect of the streamlined rime ice shape is negligible. At the free-stream Mach number of Minfinity =0.23, the glaze ice causes a 3.2 percent decrease in the total pressure recovery and a 26 percent reduction in the inlet mass flow rate. This result comes from the massive flow separation and flow blockage from the glaze ice horns. The total pressure recovery is further decreased by 22.8 percent, as the free-stream Mach number increases to Minfinity=0.85, due to the increased internal blockage and formation of internal shocks in the S-duct inlet. Also, the glaze iced inlet induces 6.6 percent increase in the engine thrust loss and the specific fuel consumption at Minfinity=0.25. The level of the ice-induced flow blockage by the ice accretion is also important for the inlet performance. The symmetrical glaze ice that covers the entire inlet lip portion causes a nearly 11.8 percent decrease in the total pressure recovery at Minfinity=0.475, whereas the top- or bottom-asymmetrical glaze ice that accretes on a portion of the inlet lip leads to just a 2.5 percent decrease. Also, the dynamic inlet distortion level, which is represented by the total pressure fluctuation at the engine face, is almost doubled with the symmetrical glaze ice when compared to the asymmetrical glaze ice. Therefore, the dynamic inlet distortion is proportional to the total pressure recovery that corresponds to the steady-state inlet distortion. Furthermore, the application of local angles of attack and local sideslip angles for the iced S-duct inlet contributes to the further degradation of the inlet performance, regardless of the ice shapes. However, the angles that provide the most distortion for each ice shape all differ due to the combined effects of the angle of attack or sideslip angle, icing location, and downward duct curvature. In addition, both the steady-state inlet distortion and dynamic inlet distortion become most severe at the highest angles tested: symmetrical (alpha=+20°), top-asymmetrical (alpha=-20°), bottom-asymmetrical (alpha=+20°), and side-asymmetrical glaze (beta=-20°). Finally, a strongly coupled temperature-total pressure distortion is created at the engine face under the icing condition. This coupling, as measured by the total pressure distortion parameter, increases the engine face distortion by 6.97 percent in the glaze iced inlet at Minfinity=0.85 when the inlet wall is heated to 350 K.

Jin, Wonjin

142

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

143

Experimentally determined aeroacoustic performance and control of several sonic inlets  

Microsoft Academic Search

Low speed wind tunnel tests were conducted to determine the aeroacoustic performance of several model sonic inlets. The results were analyzed to indicate how inlet aeroacoustic characteristics were affected by inlet design and operating conditions. A system for regulating sonic inlet noise reduction was developed and tested. Results indicate that pressure losses at forward velocity may be substantially less than

B. A. Miller

1975-01-01

144

Coastal Inlets Research Program ERDC Coastal and Hydraulics Laboratory1/48 Coastal Inlets Research Program  

E-print Network

Laboratory2/48 Prediction of Long-term Morphology Change at Coastal Inlets After a decade of R&D, CIRP procedures and guidance defining the state of the art. CIRP Mission #12;Coastal Inlets Research Program ERDC of R&D Coverage MICRO sec-min MESO hour-week MACRO month-year MEGA decade- century ULTRA century

US Army Corps of Engineers

145

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

146

Two-dimensional symmetrical inlets with external compression  

NASA Technical Reports Server (NTRS)

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

Ruden, P

1950-01-01

147

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

148

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

149

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

150

Inlet flow distortion in turbomachinery  

NASA Technical Reports Server (NTRS)

A single stage axial compressor with distorted inflow is studied. The inflow distortion occurs far upstream and may be a distortion in stagnation temperature, stagnation pressure or both. The blade rows are modeled as semi-actuator disks. Losses, quasi-steady deviation angles, and reference incidence correlations are included in the analysis. Both subsonic and transonic relative Mach numbers are considered. A parameter study is made to determine the influence of such variables as Mach number and swirl angle on the attenuation of the distortion.

Seidel, B. S.; Matwey, M. D.; Adamczyk, J. J.

1980-01-01

151

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

152

Transport phenomena in radial flow MOCVD reactor with three concentric vertical inlets  

NASA Astrophysics Data System (ADS)

Transport phenomena in radial flow metalorganic chemical vapor deposition (MOCVD) reactor with three concentric vertical inlets are studied by two-dimensional numerical modeling. By varying the parameters such as gas pressure, flow rates combination of multi-inlets, geometric shapes and sizes of reactor and flow distributor, temperatures of susceptor and ceiling, and susceptor rotation, the corresponding velocity, temperature, and concentration fields inside the reactor are obtained; the onset and change of flow recirculation cells under influences of those parameters are determined. It is found that recirculation cells, originated from flow separation near the bend of reactor inlets, are affected mainly by the reactor height and shape, the operating pressure, the flow rates combination of multi-inlets, and the mean temperature between susceptor and ceiling. By increasing the flow rate of mid-inlet and the mean temperature, decreasing the pressure, maintaining the reactor height below certain criteria, and trimming the bends of reactor wall and flow distributor to streamlined shape, the recirculation cells can be minimized so that smooth and rectilinear flow prevails in the susceptor region, which corresponds to smooth and rectilinear isotherms and larger reactant concentration near the susceptor. For the optimized reactor shape, the reactor size can be enlarged to diameter D=40 cm and height H=2 cm without flow recirculation. The susceptor rotation over a few hundred rpm around the reactor central axis will induce the recirculation cell near the exit and deflect the streamlines near the susceptor, which is not the case for vertical reactors.

Zuo, Ran; Zhang, Hong; Liu, Xiang-lin

2006-08-01

153

Experimentally determined aeroacoustic performance and control of several sonic inlets  

NASA Technical Reports Server (NTRS)

Low speed wind tunnel tests were conducted to determine the aeroacoustic performance of several model sonic inlets. The results were analyzed to indicate how inlet aeroacoustic characteristics were affected by inlet design and operating conditions. A system for regulating sonic inlet noise reduction was developed and tested. Results indicate that pressure losses at forward velocity may be substantially less than those at static conditions. This is particularly true for translating centerbody inlets with the centerbody extended in the approach and landing position. Operation to simulated take-off incidence angles of 50 deg was demonstrated with good inlet performance. Results suggest that at takeoff, with 0 deg incidence angle, sonic inlet total pressure losses need not exceed those generated by skin friction for sound pressure level reductions to at least 15 dB. Inlet sound pressure level reduction was regulated to within approximately plus or minus 1 dB by controlling inlet surface static pressure measured at the diffuser exit.

Miller, B. A.

1975-01-01

154

Cook Inlet operators face question of abandonment  

Microsoft Academic Search

Because of the decline of the Cook Inlet Basin's oil and gas fields, operators are being forced to make difficult decisions on the economic feasibility of sustaining certain production against numerous odds. Oil operators are studying the prospects of a dual oil and gas operation to extend the life of the platforms.

1983-01-01

155

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....

156

33 CFR 117.289 - Hillsboro Inlet.  

Code of Federal Regulations, 2010 CFR

... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.289 Hillsboro Inlet. The drawspans of the SR A-1-A Drawbridge, mile 0.3 at Hillsboro Beach, must open on signal; except that, from 7 a.m. to 6 p.m.,...

2010-07-01

157

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...

158

Biases in ion transmission through an electrospray ionization - mass spectrometry capillary inlet  

PubMed Central

A heated capillary inlet for an electrospray ionization mass spectrometry (ESI-MS) interface was compared with shorter versions of the inlet to determine the effects on transmission and ionization efficiencies for low-flow (nano) electrosprays. Five different inlet lengths were studied, ranging from 6.4 to 1.3 cm. As expected, the electrospray current transmission efficiency increased with decreasing capillary length due to reduced losses to the inside walls of the capillary. This increase in transmission efficiency with shorter inlets was coupled with reduced desolvation of electrosprayed droplets. Surprisingly, as the inlet length was decreased, some analytes showed little or no increase in sensitivity, while others showed as much as a15 – fold gain. The variation was shown to beat least partially correlated with analyte mobilities, with the largest gains observed for higher mobility species, but also affected by solution conductivity, flow rate, and inlet temperature. Strategies for maximizing sensitivity while minimizing biases in ion transmission through the heated capillary interface are proposed. PMID:19815425

Page, Jason S.; Marginean, Ioan; Baker, Erin S.; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

2010-01-01

159

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

160

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.

161

Copper-triazole interaction and coolant inhibitor depletion  

SciTech Connect

To a large extent, the depletion of tolyltriazole (TTZ) observed in several field tests may be attributed to the formation of a protective copper-triazole layer. Laboratory aging studies, shown to correlate with field experience, reveal that copper-TTZ layer formation depletes coolant TTZ levels in a fashion analogous to changes observed in the field. XPS and TPD-MS characterization of the complex formed indicates a strong chemical bond between copper and the adsorbed TTZ which can be desorbed thermally only at elevated temperatures. Electrochemical polarization experiments indicate that the layer provides good copper protection even when TTZ is absent from the coolant phase. Examination of copper cooling system components obtained after extensive field use reveals the presence of a similar protective layer.

Bartley, L.S.; Fritz, P.O.; Pellet, R.J.; Taylor, S.A.; Van de Ven, P. [Texaco Fuels and Lubricants Technology Dept., Beacon, NY (United States)

1999-08-01

162

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.

163

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

164

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

165

1. OVERALL VIEW OF LOBOS CREEK INLET STRUCTURE (#1786), LOOKING ...  

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

1. OVERALL VIEW OF LOBOS CREEK INLET STRUCTURE (#1786), LOOKING SOUTHWEST - Presidio Water Treatment Plant, Lobos Creek Inlet Structure, East of Lobos Creek at Baker Beach, San Francisco, San Francisco County, CA

166

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

167

46 CFR 153.354 - Venting system inlet.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Venting system inlet. 153.354 Section 153.354 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY...Design and Equipment Cargo Venting Systems § 153.354 Venting system inlet. A venting system must...

2010-10-01

168

Experimentally determined aeroacoustic performance and control of several sonic inlets  

NASA Technical Reports Server (NTRS)

Low speed wind tunnel tests were conducted to determine the aeroacoustic performance of several model sonic inlets. The results were analyzed to indicate how inlet aeroacoustic characteristics were affected by inlet design and operating conditions. A system for regulating sonic inlet noise reduction was developed and tested. Results indicate that pressure losses at forward velocity may be substantially less than those at static conditions. This is particularly true for translating centerbody inlets with the centerbody extended in the approach and landing position. Operation to simulated takeoff incidence angles of 50 degrees was demonstrated with good inlet performance. Inlet sound pressure level reduction was regulation was regulated to within approximately + or - 1 dB by controlling inlet surface static pressure measured at the diffuser exit.

Miller, B. A.

1975-01-01

169

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

170

Influence of inlet conditions on vortex characteristics  

NASA Astrophysics Data System (ADS)

Vortex chambers are normally used for arc stabilization in linear plasma torches. In the present work, the effect of uniformity of the gas inlet channel distribution on the stabilizing characteristics of a swirled flow is studied numerically. The formation of a complex flow pattern with a toroidal recirculating flow area inside the vortex chamber is observed. For some regimes, two local maxima of the tangential velocity are observed in the middle section of the chamber. It is shown that an increment of the number of gas inlet channels leads to a more uniform gas input with disappearance of the second maximum, which increases the velocity amplification coefficient and, correspondingly, results in a better stabilizing effect. The obtained profiles of the radial distribution of the tangential velocity are compared with the results of Oseen's equation for an unconfined vortex.

Essiptchouk, A.

2011-09-01

171

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

172

Failure investigation of gas inlet chamber  

Microsoft Academic Search

The paper presents the results of a failure investigation carried out on a cracked gas inlet chamber. The plant found a crack on a 24in. pipe, made of 304H stainless steel, near a 3\\/4in. steam purge nozzle. The plant carried out repair welding using gas tungsten arc welding. However, after the repair welding and two months service, large size intergranular

H. M. Shalaby; W. T. Riad

2008-01-01

173

Coastal Inlets Research Program ERDC/CHLTR-06-1  

E-print Network

Coastal Inlets Research Program ERDC/CHLTR-06-1 Evaluation of Downdrift Shore Erosion, MattituckHydraulicsLaboratory Approved for public release; distribution is unlimited. #12;Coastal Inlets Research Program ERDC/CHL TR-06-1 April 2006 Evaluation of Downdrift Shore Erosion, Mattituck Inlet, New York: Section 111 Study Brian K

US Army Corps of Engineers

174

ERDC/CHLTR-05-8 Coastal Inlets Research Program  

E-print Network

, and shoreline erosion are all concerns at coastal inlets and are related to the transformation of wavesERDC/CHLTR-05-8 Coastal Inlets Research Program Laboratory Study of Hydrodynamics Near AbsorbingHydraulicsLaboratory Approved for public release; distribution is unlimited. #12;Coastal Inlets Research Program ERDC/CHL TR-05

US Army Corps of Engineers

175

Flow Analysis and Control in a Transonic Inlet  

Microsoft Academic Search

Traditional aerodynamic inlet design tends to optimize the shape of the duct for the cruise condition. However, during manoeuvres both the external conditions and interaction with the forebody can create drastic losses. In particular, separation can occur inside the inlet duct and generate compressor face distortion leading to instabilities, especially in compact air inlets such as those used on missiles.

Serge E. Tournier; James D. Paduano

176

Inlet total pressure loss due to acoustic wall treatment  

Microsoft Academic Search

Experimental determination of the effect of diffuser wall acoustic treatment on inlet total pressure loss. Data were obtained by testing an inlet model with 10 different acoustically treated diffusers differing only in the design of the Helmholtz resonator acoustic treatment. Tests were conducted in a wind tunnel at forward velocities to 41 meters per second for inlet throat Mach numbers

B. A. Miller

1977-01-01

177

An experimental investigation of flow control for supersonic inlets  

E-print Network

Falcon (see Hawkins (1976) for a good description of this particular inlet configuration). The main advantage of a Pitot inlet is its innate simplicity. In addition, if the Pitot inlet is nose mounted then the only shock-wave will not interact with any...

Titchener, Neil

2013-07-09

178

Status of Physics and Safety Analyses for the Liquid-Salt-Cooled Very High-Temperature Reactor (LS-VHTR)  

SciTech Connect

A study has been completed to develop a new baseline core design for the liquid-salt-cooled very high-temperature reactor (LS-VHTR) that is better optimized for liquid coolant and that satisfies the top-level operational and safety targets, including strong passive safety performance, acceptable fuel cycle parameters, and favorable core reactivity response to coolant voiding. Three organizations participated in the study: Oak Ridge National Laboratory (ORNL), Idaho National Laboratory (INL), and Argonne National Laboratory (ANL). Although the intent was to generate a new reference LS-VHTR core design, the emphasis was on performing parametric studies of the many variables that constitute a design. The results of the parametric studies not only provide the basis for choosing the optimum balance of design options, they also provide a valuable understanding of the fundamental behavior of the core, which will be the basis of future design trade-off studies. A new 2400-MW(t) baseline design was established that consists of a cylindrical, nonannular core cooled by liquid {sup 7}Li{sub 2}BeF{sub 4} (Flibe) salt. The inlet and outlet coolant temperatures were decreased by 50 C, and the coolant channel diameter was increased to help lower the maximum fuel and vessel temperatures. An 18-month fuel cycle length with 156 GWD/t burnup was achieved with a two-batch shuffling scheme, while maintaining a core power density of 10 MW/m{sup 3} using graphite-coated uranium oxicarbide particle fuel enriched to 15% {sup 235}U and assuming a 25 vol-% packing of the coated particles in the fuel compacts. The revised design appears to have excellent steady-state and transient performance. The previous concern regarding the core's response to coolant voiding has been resolved for the case of Flibe coolant by increasing the coolant channel diameter and the fuel loading. Also, the LSVHTR has a strong decay heat removal performance and appears capable of surviving a loss of forced circulation (LOFC) even with failure to scram. Significant natural convection of the coolant salt occurs, resulting in fuel temperatures below steady-state values and nearly uniform temperature distributions during the transient.

Ingersoll, DT

2005-12-15

179

Petroleum geology of Cook Inlet basin - an exploration model  

USGS Publications Warehouse

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

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

1981-01-01

180

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

181

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

182

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

183

Limits to fuel/coolant mixing  

SciTech Connect

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

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

1985-05-01

184

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

185

Emergency cooling analysis for the loss of coolant malfunction  

NASA Technical Reports Server (NTRS)

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

Peoples, J. A.

1972-01-01

186

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

187

One-dimensional analysis of the behaviour of wet steam at different inlet conditions  

NASA Astrophysics Data System (ADS)

The main aim of this paper is to estimate the likely behaviour of steam during an expansion process with the variation in the total inlet temperature. It is well-acknowledged that the position of limiting supersaturation was dependent on the steam conditions at inlet. Based on this hypothesis, an improved mathematical model is developed to observe the effect of changing the inlet total temperature to the flow properties. In the present work, a one-dimensional (1-D) time-marching compressible Euler solver that uses the second order cell-vertex finite volume spatial discretization and fourth orders Runge-Kutta temporal integration has been developed. Artificial viscosity is added by using Jameson's type 2nd and 4th. A single dimension is considered here as to demonstrate the main effects of spontaneous condensation without necessary complexity. The boundary conditions across the nozzle are imposed in the calculations. Based on the calculation, it is clear that the Mach number and pressure ratio is a good representation to the onset of condensation and are highly dependent on the total inlet temperature.

Malek, Norhazwani Abd; Hasini, Hasril; Yusoff, Mohd Zamri

2012-06-01

188

Vortex tube can increase liquid hydrocarbon recovery at plant inlet  

SciTech Connect

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

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

1997-09-08

189

NASCRIN - NUMERICAL ANALYSIS OF SCRAMJET INLET  

NASA Technical Reports Server (NTRS)

The NASCRIN program was developed for analyzing two-dimensional flow fields in supersonic combustion ramjet (scramjet) inlets. NASCRIN solves the two-dimensional Euler or Navier-Stokes equations in conservative form by an unsplit, explicit, two-step finite-difference method. A more recent explicit-implicit, two-step scheme has also been incorporated in the code for viscous flow analysis. An algebraic, two-layer eddy-viscosity model is used for the turbulent flow calculations. NASCRIN can analyze both inviscid and viscous flows with no struts, one strut, or multiple struts embedded in the flow field. NASCRIN can be used in a quasi-three-dimensional sense for some scramjet inlets under certain simplifying assumptions. Although developed for supersonic internal flow, NASCRIN may be adapted to a variety of other flow problems. In particular, it should be readily adaptable to subsonic inflow with supersonic outflow, supersonic inflow with subsonic outflow, or fully subsonic flow. The NASCRIN program is available for batch execution on the CDC CYBER 203. The vectorized FORTRAN version was developed in 1983. NASCRIN has a central memory requirement of approximately 300K words for a grid size of about 3,000 points.

Kumar, A.

1994-01-01

190

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

191

River temperature fluctuation problem.  

National Technical Information Service (NTIS)

Observed fluctuations of river temperature have on occasion required that power level be reduced so as to stay within coolant temperature limits. D Reactor greatest variation with sizeable fluctuations also observed has experienced the greatest variation ...

L. D. Gustafson

1965-01-01

192

Temperature response of turbulent premixed flames to inlet velocity oscillations  

Microsoft Academic Search

Flame–turbulence interactions are at the heart of modern combustion research as they have a major influence on efficiency,\\u000a stability of operation and pollutant emissions. The problem remains a formidable challenge, and predictive modelling and the\\u000a implementation of active control measures both rely on further fundamental measurements. Model burners with simple geometry\\u000a offer an opportunity for the isolation and detailed study

B. Ayoola; G. Hartung; C. A. Armitage; J. Hult; R. S. Cant; C. F. Kaminski

2009-01-01

193

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

194

Coolant quality for magnetic resonance imaging systems  

Microsoft Academic Search

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

Julie Wong; Garron K Morris

2008-01-01

195

Properties and stability of a Texas barrier beach inlet  

E-print Network

OP A TEXAS BARRIER BEACH INLET (August 1971) Curtis Mason, B. A. , Oregon State University; M. S. , Texas A6M University; Directed by: Dr. Robert M. Sorensen An environmental study was conducted at Brawn Cedar Cut, a natural unstable barrier... of astronomi- cal tidal currents leads to degradation of the inlet channel and westward migration of the entire inlet system. iv ACKNOWLEDGMENTS The author would like to thank Dr. Robert M. Sorensen for his direction and assistance while acting...

Mason, Curtis

2012-06-07

196

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

197

Geologic framework of lower Cook Inlet, Alaska  

USGS Publications Warehouse

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

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

1978-01-01

198

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

199

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

200

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

NASA Technical Reports Server (NTRS)

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

Dustin, M. O. (inventor)

1975-01-01

201

April 7, 1998 Studies of Coolant Compatibility with Beryllium  

E-print Network

CBX 98­8 April 7, 1998 D.Cinabro S.McGee Studies of Coolant Compatibility with Beryllium Abstract A study of the petroleum­based coolant, PF200, has found it to be chemically compat­ ible with beryllium. These features make PF200 a suitable substitute for water in the coolant system of CLEO's beryllium beam pipe. 1

Cinabro, David

202

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

203

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

204

Efficiency of carbon nanotubes water based nanofluids as coolants Salma Halelfadl a  

E-print Network

1 Efficiency of carbon nanotubes water based nanofluids as coolants Salma Halelfadl a , Thierry of water-based nanofluids containing carbon nanotubes, stabilized by SDBS as surfactant, are experimentally, thermal conductivity and viscosity of nanofluids is investigated for temperature range of 20°C to 40°C

Paris-Sud XI, Université de

205

Heat transfer in the coolant channel of a heat-exchanger system based on fluctuation theories  

Microsoft Academic Search

We present a model to study the heat transfer in the coolant channel of a heat-exchanger system. Such a model introduces thermal fluctuations as well as external noises due to different mechanisms of heat interchange. A unified treatment of both kinds of noise is carried out. The stationary mean value of the channel temperature is studied, obtaining effective transport coefficients

A. Díaz-Guilera; M. A. Rodríguez; J. M. Rubí

1988-01-01

206

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

207

KILLER WHALE PREDATION ON BELUGAS IN COOK INLET, ALASKA: IMPLICATIONS  

E-print Network

KILLER WHALE PREDATION ON BELUGAS IN COOK INLET, ALASKA: IMPLICATIONS FOR A DEPLETED POPULATION KIM Killer whale predation on belugas in Cook Inlet, Alaska, has become a concern since the decline of these belugas was documented during the 1990s. Accordingly, killer whale sightings were compiled from systematic

208

Volcanic tsunamis and prehistoric cultural transitions in Cook Inlet, Alaska  

Microsoft Academic Search

The 1883 eruption of Augustine Volcano produced a tsunami when a debris avalanche traveled into the waters of Cook Inlet. Older debris avalanches and coeval paleotsunami deposits from sites around Cook Inlet record several older volcanic tsunamis. A debris avalanche into the sea on the west side of Augustine Island ca. 450 years ago produced a wave that affected areas 17 m

James Begét; Cynthia Gardner; Kathleen Davis

2008-01-01

209

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

210

A simulation method based on SIMULINK for a supersonic inlet  

Microsoft Academic Search

This paper has developed a computational platform of a supersonic inlet with variable geometry, using MATLAB\\/SIMULINK. A method based on this for simulation of a complicated model has been presented. The correctness and reliability of the new method have been testified by simulating the stationary flow fields of an inlet under back pressure gust and gust of parameters of incoming

Wen Bao; Zhaohui Yao; Baocheng He; Juntao Chang

2006-01-01

211

Overview of the Light Aircraft Aerosol Research Inlet (LAARI)  

Microsoft Academic Search

Aircraft provide a mobile platform for measuring vertical profile aerosol properties. The efficacy of these measurements, however, is constrained by the aerosol inlet sampling efficiency. Larger particles are often lost to turbulent deposition and impaction inside the inlet and sampling lines, respectively. This precludes the measurement of coarse mode particles, important to visibility and radiative transfer studies. Turbulent deposition of

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

2004-01-01

212

Experimental and Numerical Investigation of Hypersonic Jaws Inlet  

Microsoft Academic Search

In order to obtain the flow field characteristics and the influence of boundary layer, numerical simulations and wind tunnel tests are conducted for two streamline traced Jaws inlets at Mach number 7. The inlets are designed based on a flow field with 8-7 planar shock wave (the ramp in pitch plane is inclined at 8° to the free stream and

Hao Dong; Cheng-Peng Wang; Ke-Ming Cheng

2010-01-01

213

On the Design of Hypersonic InwardTurning Inlets  

Microsoft Academic Search

There has been a recent re-emphasis in the exploration of hypersonic inlets utilizing circular or elliptical cross sections due to advantages in structural integrity, flow distortion and propulsive eciencies as compared with similar rectangular devices. A family of dual axis compression, high contraction ratio inward-turning inlets has been designed to achieve a desired shock structure and aerodynamic performance at Mach

A. Croker

214

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

National Technical Information Service (NTIS)

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

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

2005-01-01

215

Ocean City Inlet, Maryland: a catalyst for coastal change  

SciTech Connect

Ocean City Inlet is located along the microtidal Atlantic Ocean coastline of Maryland. The inlet was opened by a hurricane in 1933 and stabilized with a double jetty system in 1934. Dramatic shoreline recession has occurred downdrift of the inlet with accretion to the north. Analysis of these trends has led past researchers to conclude that inlet stabilization is the principal cause. Analysis of shoreline position change maps for the period 1849-1980 reveals that this area had been receding significantly prior to inlet stabilization. For the period 1849-1933, a 16km long recessional embayment was centered about 16km south of the present inlet. Maximum mean shoreline recession rates approached 4m/yr near the center of the embayment. During the period from 1933-1980, maximum mean recession rates south of the inlet approached 8m/yr. The measured recession rates of northern Assateague Island represent island migration, not erosion. The cartographic area has shown little change during the 130+ years of shoreline mapping. The coastal geomorphic changes observed at Ocean City represent response to long term coastal processes, perhaps re-adjustment due to the rise in Holocene sea-level. Ocean City Inlet may be a catalyst for the observed changes, exaggerating a pre-existing process-response system.

Knowles, S.C.; May, S.K.

1985-01-01

216

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....

217

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

218

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

NASA Astrophysics Data System (ADS)

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

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

1992-12-01

219

Parametric Analysis of a Hypersonic Inlet using Computational Fluid Dynamics  

NASA Astrophysics Data System (ADS)

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

Oliden, Daniel

220

First principles calculations predict stable 50 nm nickel ferrite particles in PWR coolant  

NASA Astrophysics Data System (ADS)

Thermodynamic calculations that combine experimental data with the results of first principles calculations yield negative free energies for {1 1 1} surfaces of nickel ferrite for the temperature, pressure and ion concentrations typical of Pressurized Light Water Reactor (PWR) coolant. When combined with a positive bulk free energy of formation, the negative surface energies predict that thermodynamically-stable octahedral nickel ferrite particles with diameters of ?50 nm should be present in PWR coolant during operation. These particles would not be removed by mixed bed demineralizers and would be below the filter pore sizes typically used in Chemical and Volume Control Systems. The calculations also predict that these particles are not thermodynamically stable in coolant under ambient conditions. Based on these results it is proposed that solvated nickel ferrite particles, which are predicted to be stable and likely long-lived in PWR primary coolant, contribute to the nucleation of metal oxide scale on PWR fuel rod cladding and that conventional methods for purifying the primary coolant may be ineffective in removing these species.

O'Brien, C. J.; Rák, Zs.; Bucholz, E. W.; Brenner, D. W.

2014-11-01

221

Assessment of effects of Fort St. Vrain HTGR primary coolant on Alloy 800. Final report  

SciTech Connect

A comprehensive review was conducted of primary helium coolant chemistry data, based on current and past operating histories of helium-cooled, high-temperature reactors (HTGRs), including the Fort St. Vrain (FSV) HTGR. A reference observed FSV reactor coolant environment was identified. Further, a slightly drier expected FSV coolant chemistry was predicted for reactor operation at 100% of full power. The expected environment was compared with helium test environments used in the US, United Kingdom, Germany, France, and Japan. Based on a comprehensive review and analysis of mechanical property data reported for Alloy 800 tested in controlled-impurity helium environments (and in air when appropriate for comparison), an assessment was made of the effect of FSV expected helium chemistry on material properties of alloy 800, with emphasis on design properties of the Alloy 800 material utilized in the FSV steam generators.

Trester, P.W.; Johnson, W.R.; Simnad, M.T.; Burnette, R.D.; Roberts, D.I.

1982-08-01

222

Large-break loss-of-coolant accidents in the updated PIUS 600 advanced reactor design  

SciTech Connect

The PIUS advanced reactor is a 640-MWe pressurized water reactor concept developed by Asea Brown Boveri. A unique feature of PIUS is the absence of mechanical control and shutdown rods. Reactivity is controlled by coolant boron concentration and the temperature of the moderator coolant. Los Alamos is supporting the US Nuclear Regulatory Commission`s preapplication review of the PIUS reactor. Baseline calculations of the PIUS Supplement design were performed for a large-break loss-of-coolant (LBLOCA) initiator using TRAC-PF1/MOD2. Additional sensitivity studies examined flow blockage and boron dilution events to explore the robustness of the PIUS concept for low-probability combination events following an LBLOCA.

Steiner, J.L.; Harmony, S.C.; Stumpf, H.J.; Lime, J.F.; Boyack, B.E. [Los Alamos National Lab., NM (United States). Technology and Safety Assessment Division

1994-12-31

223

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

NASA Technical Reports Server (NTRS)

A wind tunnel investigation was conducted to determine the local inlet flow field characteristics of an advanced tactical supersonic cruise airplane. A data base for the development and validation of analytical codes directed at the analysis of inlet flow fields for advanced supersonic airplanes was established. Testing was conducted at the NASA-Langley 16-foot Transonic Tunnel at freestream Mach numbers of 0.6 to 1.20 and angles of attack from 0.0 to 10.0 degrees. Inlet flow field surveys were made at locations representative of wing (upper and lower surface) and forebody mounted inlet concepts. Results are presented in the form of local inlet flow field angle of attack, sideflow angle, and Mach number contours. Wing surface pressure distributions supplement the flow field data.

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

1984-01-01

224

Catalytically-Promoted Analyte Derivatization Inside a Gas Chromatographic Inlet  

PubMed Central

Reported here is a preliminary assessment of the feasibility of catalyzing on-line derivatization reactions inside the inlet (i.e., the injection port) of a gas chromatograph (GC) with solid heterogeneous catalysts. The experiments described here entail the installation of candidate catalysts inside the GC inlet liner and the subsequent injection of analyte/reagent mixtures onto the catalyst beds. Two catalysts are identified, each of which clearly catalyzes one of the chosen model derivatization reactions in the inlet of a GC. This result supports our hypothesis that on-line derivatizations can, in principle, be reproducibly catalyzed inside the GC inlet by solid heterogeneous catalysts and that the presence of such catalysts in the inlet do not necessarily cause a serious loss of instrument performance or chromatographic efficiency. PMID:20822662

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

2010-01-01

225

Investigation of a mixed compression axisymmetric inlet at Mach number 5.3  

NASA Technical Reports Server (NTRS)

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

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

1972-01-01

226

Evaluation of engine coolant recycling processes: Part 2  

SciTech Connect

Engine coolant recycling continues to provide solutions to both economic and environmental challenges often faced with the disposal of used engine coolant. General Motors` Service Technology Group (STG), in a continuing effort to validate the general practice of recycling engine coolants, has conducted an in-depth study on the capabilities of recycled coolants. Various recycling processes ranging from complex forms of fractional distillation to simple filtration were evaluated in this study to best represent the current state of coolant recycling technology. This study incorporates both lab and (limited) fleet testing to determine the performance capabilities of the recycled coolants tested. While the results suggest the need for additional studies in this area, they reveal the true capabilities of all types of engine coolant recycling technologies.

Bradley, W.H. [General Motors, Warren, MI (United States). Service Technology Group

1999-08-01

227

Assessment of tidal inlet evolution and stability using sediment budget computations and hydraulic parameter analysis  

Microsoft Academic Search

Research into the response of coastlines to the opening and stabilisation of inlets has been limited by the availability of suitable data, the shortcomings of existing formulae when applied to different inlets, and the difficulties particular to multi-inlet situations. Our appraisal of methodologies for studying inlet dynamics leads us to formulate a new approach for investigating inlet evolution and stability

A. Pacheco; A. Vila-Concejo; Ó. Ferreira; J. A. Dias

2008-01-01

228

Effect of casing treatment on performance of an inlet stage for a transonic multistage compressor  

NASA Technical Reports Server (NTRS)

An inlet stage of a transonic compressor was tested with three rotor tip casing treatment configurations: blade angle slots, circumferential grooves, and axial skewed slots. Significant increases in both rotor and stage total pressure ratio, total temperature ratio, efficiency, flow range, and very large improvements in stall margin were obtained with all three casing treatment configurations. The greatest improvement in performance was achieved with axial skewed slots.

Urasek, D. C.; Lewis, G. W., Jr.; Moore, R. D.

1976-01-01

229

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

230

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

of the inlet as part of an erosion-control project conducted in the late 1990s, inlet maintenance increased geomorphic trends, the Coastal Modeling System (CMS) was established to numerically simulate waves, current Jersey shore and is the northernmost inlet on this coast (Figure 1). The inlet is served by a federally

US Army Corps of Engineers

231

Unstart coupling mechanism analysis of multiple-modules hypersonic inlet.  

PubMed

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

Hu, Jichao; Chang, Juntao; Wang, Lei; Cao, Shibin; Bao, Wen

2013-01-01

232

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

233

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

234

Selling cold air DSM incentives lead to combustion turbine inlet air cooling opportunities for ESCOs  

SciTech Connect

Declining capacity margins and increasing competition among many electric utilities are putting new pressures on utility demand-side management (DSM) planners and the demand-side resource plans they develop. Most of this pressure has resulted from utilities` experiences with DSM programs that have not produced the impacts initially anticipated. Therefore, when responding to solicitations for demand-side resources, energy service companies (ESCOs) and other DSM contractors have been forced to focus increasingly on the measurability and reliability of the DSM packages they offer utilities. This paper proposes that combustion turbine (CT) inlet air cooling could be packaged as a demand-side resource to help utilities and ESCOs avoid the measurability and reliability problems of some other types of DSM programs. With CT inlet air cooling, in which ice is produced off-peak and stored for increasing CT capacity during summer peak periods by cooling the inlet air temperature, two utilities have obtained a reliable 67 MW (combined) resource for a total cost of about $15.4 million, or $230 per kW. Because this technology`s ability to meet peak demands is the result of predictable physical properties, the certainty of the impact of CT inlet air cooling is an attractive feature to electric utilities that are facing new competitive pressures to scrutinize the economics of all their DSM programs. This paper shows that minor modifications to existing DSM incentive mechanisms, such as PSE and G`s Standard Offer, could provide the necessary financing framework to lead to a boom in the CT inlet air cooling DSM market for ESCOs and other DSM contractors.

Sullivan, J.; Ebeling, J.A. [Burns and McDonnell Engineering Co., Kansas City, MO (United States)

1994-12-31

235

FILM-30: A Heat Transfer Properties Code for Water Coolant  

SciTech Connect

A FORTRAN computer code has been written to calculate the heat transfer properties at the wetted perimeter of a coolant channel when provided the bulk water conditions. This computer code is titled FILM-30 and the code calculates its heat transfer properties by using the following correlations: (1) Sieder-Tate: forced convection, (2) Bergles-Rohsenow: onset to nucleate boiling, (3) Bergles-Rohsenow: partially developed nucleate boiling, (4) Araki: fully developed nucleate boiling, (5) Tong-75: critical heat flux (CHF), and (6) Marshall-98: transition boiling. FILM-30 produces output files that provide the heat flux and heat transfer coefficient at the wetted perimeter as a function of temperature. To validate FILM-30, the calculated heat transfer properties were used in finite element analyses to predict internal temperatures for a water-cooled copper mockup under one-sided heating from a rastered electron beam. These predicted temperatures were compared with the measured temperatures from the author's 1994 and 1998 heat transfer experiments. There was excellent agreement between the predicted and experimentally measured temperatures, which confirmed the accuracy of FILM-30 within the experimental range of the tests. FILM-30 can accurately predict the CHF and transition boiling regimes, which is an important advantage over current heat transfer codes. Consequently, FILM-30 is ideal for predicting heat transfer properties for applications that feature high heat fluxes produced by one-sided heating.

MARSHALL, THERON D.

2001-02-01

236

The effect of inlet conditions on lean premixed gas turbine combustor performance  

NASA Astrophysics Data System (ADS)

The combustion community is today faced with the goal to reduce NOx at high efficiencies. This requirement has directed attention to the manner by which air and fuel are treated prior to and at the combustor inlet. This dissertation is directed to establishing the role of combustor inlet conditions on combustor performance, and to deriving an understanding of the relationship between inlet conditions and combustion performance. To investigate the complex effect of inlet parameters on combustor performance, (1) a test facility was designed and constructed, (2) hardware was designed and fabricated, (3) a statistically based technique was designed and applied, and (4) detailed in-situ measurements were acquired. Atmospheric tests were performed at conditions representative of industrial combustors: 670 K inlet preheat and an equivalence ratio of 0.47, and make the study immediately relevant to the combustion community. The effects of premixing length, fuel distribution, swirl angle, swirl vane thickness and swirl solidity were investigated. The detailed in-situ measurements were performed to form the database necessary to study the responsible mechanisms. A host of conventional and advanced diagnostics were used for the investigation. In situ measurements included the mapping of the thermal and velocity fields of the combustor, obtaining species concentrations inside the combustor, and quantifying the fuel-air mixing entering the combustor. Acoustic behavior of the combustor was studied, including the application of high speed videography. The results reveal that the principal statistically significant effect on NOx production is the inlet fuel distribution, and the principal statistically significant effect on CO production is the swirl strength. Elevated levels of NOx emission result when the fuel is weighted to the centerline. Eddies shedding off the swirler hub ignite as discrete packets, and due to the elevated concentrations of fuel, reach higher temperatures than uniformly mixed packets. This shedding of eddies leads to an acoustic emission that can be identified in a select frequency range. The CO production is related to the swirl strength due to the proportion of products entrained into the recirculation zone. Neither lean blowout nor combustion efficiency are affected by the inlet condition variation within the range studied.

Vilayanur, Suresh Ravi

237

Experimental investigation of a Mach 6 fixed-geometry inlet featuring a swept external-internal compression flow field  

NASA Technical Reports Server (NTRS)

An investigation of a fixed-geometry, swept external-internal compression inlet was conducted at a Mach number of 6.0 and a test-section Reynolds number of 1.55 x 10 to the 7th power per meter. The test conditions was constant for all runs with stagnation pressure and temperature at 20 atmospheres and 500 K, respectively. Tests were made at angles of attack of -5 deg, 0 deg, 3 deg, and 5 deg. Measurements consisted of pitot- and static-pressure surveys in inlet throat, wall static pressures, and surface temperatures. Boundary-layer bleed was provided on the centerbody and on the cowl internal surface. The inlet performance was consistently high over the range of the angle of attack tested, with an overall average total pressure recovery of 78 percent and corresponding adiabatic kinetic-energy efficiency of 99 percent. The inlet throat flow distribution was uniform and the Mach number and pressure level were of the correct magnitude for efficient combustor design. The utilization of a swept compression field to meet the starting requirements of a fixed-geometry inlet produced neither flow instability nor a tendency to unstart.

Torrence, M. G.

1975-01-01

238

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

239

Preliminary investigation of inlet ingestion of a wing tip vortex  

NASA Technical Reports Server (NTRS)

An inlet-coldpipe assembly was placed in a Mach 0.4 stream to ingest the tip vortex of a forward mounted wing. The strongest vortex was produced by a wing angle of attack of 11 degrees. The vortex displayed a tangential velocity of 57 percent of local stream velocity prior to entering the inlet, and a tangential velocity of 25 percent of local velocity at the simulated compressor-face. The total-pressure profiles measured by standard compressor-face rakes were changed by the presence of the vortex only at the highest tested inlet mass-flow ratios.

Mitchell, G. A.

1973-01-01

240

Thoracoscopic transclavicular approach for a large thoracic inlet tumor.  

PubMed

Large lesions of the thoracic inlet represent a significant challenge to surgeons due to their close relationship with important adjacent neurovascular structures. We report a case of neurofibromatosis type 1 presented with a large neurofibroma located in the right thoracic inlet, and a malignant peripheral nerve sheath tumor in the right clavicle and treated with a hybrid thoracoscopic anterior transclavicular approach to remove the tumors. Combination of thoracoscopic and minimal chest wall resection may serve as a feasible option for resection of the large and benign thoracic inlet tumor in a way of minimal invasiveness and safety. PMID:25282248

Yan, Shi; Sun, Yu; Sun, Yingshi; Fan, Zhengfu; Phan, Kevin; Yang, Yue; Wu, Nan

2014-10-01

241

Heavy minerals in surficial sediments from lower Cook Inlet, Alaska  

USGS Publications Warehouse

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

Wong, F. L.

1984-01-01

242

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

Federal Register 2010, 2011, 2012, 2013

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

2011-05-02

243

Closed loop programmable EGR with coolant temperature sensitivity  

Microsoft Academic Search

A closed loop programmable EGR control system is disclosed. The EGR control system comprises a first read only memory having a look up table of base EGR pulse widths as a function of engine speed and absolute manifold pressure. This base EGR pulse width is corrected to a total desired pulse width by adding a correction pulse width obtained from

Toelle

1979-01-01

244

PIE Nacelle Flow Analysis and TCA Inlet Flow Quality Assessment  

NASA Technical Reports Server (NTRS)

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

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

1999-01-01

245

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

246

40 CFR 89.328 - Inlet and exhaust restrictions.  

...PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE...Equip the test engine with an air inlet system presenting an air...of the upper limit at maximum air flow, as specified by the...

2014-07-01

247

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

248

Aerodynamic and acoustic performance of high Mach number inlets  

NASA Technical Reports Server (NTRS)

Experimental results were obtained for two types of high Mach number inlets, one with a translating centerbody and one with a fixed geometry (collapsing cowl) without centerbody. The aerodynamic and acoustic performance of these inlets was examined. The effects of several parameters such as area ratio and length-diameter ratio were investigated. The translating centerbody inlet was found to be superior to the collapsing cowl inlet both acoustically and aerodynamically, particularly for area ratios greater than 1.5. Comparison of length-diameter ratio and area ratio effects on performance near choked flow showed the latter parameter to be more significant. Also, greater high frequency noise attenuation was achieved by increasing Mach number from low to high subsonic values.

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

1977-01-01

249

Two-Dimensional Inlet Simulation Using a Diagonal Implicit Algorithm.  

National Technical Information Service (NTIS)

A modification of an implicit approximate-factorization finite-difference algorithm applied to the two-dimensional Euler and Navier-Stokes equations in general curvilinear coordinates is presented for supersonic freestream flow about and through inlets. T...

D. S. Chaussee, T. H. Pulliam

1981-01-01

250

South rear, east end. Original power inlet is visible halfway ...  

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

South rear, east end. Original power inlet is visible halfway up the wall - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ

251

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

252

A dispersion curve study of dredged spoil basin inlets  

E-print Network

A DISPERSION CURVE STUDY OF DREDGED SPOIL BASIN INLETS A Thesis hy ROB E RT MALE Submitted to the Graduate College of Texas ASM Unive ra i ty in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1974 Major... Subject: Civil Engineering A DISPERSION CURVE STUDY OF DREDGED SPOIL BASIN INLETS A Thesis by ROBERT HALE Approved as to style and content by: (Chairman of Committee) / ') (Head of Departmen ( ember) August 1974 ABSTRACT A Dispersion Curve...

Male, Robert

2012-06-07

253

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

254

Experimental study of different control methods for hypersonic air inlets  

Microsoft Academic Search

An experimental study of different control methods for hypersonic air inlets aimed at ensuring reliable starting of these\\u000a apparatuses and improving their operating characteristics in the range of Mach numbers 2 to 8 is reported. Conditions for\\u000a boundary-layer separation and possibilities for preventing this separation by using modified diffuser configurations and\\/or\\u000a perforation bleedage are examined. An air-inlet model was tested

F. Falempin; M. A. Goldfeld; Yu. V. Semenova; A. V. Starov; K. Yu. Timofeev

2008-01-01

255

Experimental investigation of isolated inlets for high agile missiles  

Microsoft Academic Search

Experimental studies are accomplished with two axially symmetric inlet models with different internal compressions. Main interest lies in covering a large and flexible maneuver range at supersonic speed. This requires an analysis of the performance such as pressure recovery and mass flow.The inlets are analyzed at the design Mach number MA=3 in an angle of attack range of 0°???30° in

Dirk Herrmann; Klaus Triesch

2006-01-01

256

Performance of a respirable multi-inlet cyclone sampler  

Microsoft Academic Search

The performance of the 10mm Dorr-Oliver cyclone is known to suffer from bias associated with the dependence of its aspiration efficiency on the inlet orientation. A new multi-inlet cyclone sampler was developed to minimize such orientation bias. The sampling flow rate through the new sampler was optimized to match its performance with the newly established ISO-ACGIH-CEN respirable dust sampling convention.

Mridul Gautam; Avula Sreenath

1997-01-01

257

Design and performance of a low flowrate inlet  

Microsoft Academic Search

Several ambient air samplers that have been designated by the US EPA as Federal Reference Methods (FRMs) for measuring particulate matter nominally less than 10 micrometers (PM-10) include the use of a particular inlet design that aspirates particulate matter from the atmosphere at 16.7 l\\/m. Several studies have indicated that, under some atmospheric conditions, design flaws in this PM-10 inlet

M. P. Tolocka; R. W. Vanderpool; T. M. Peters; F. L. Chen; R. W. Wiener

1999-01-01

258

A multidisciplinary optimization method for designing boundary layer ingesting inlets  

Microsoft Academic Search

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

David Leonard Rodriguez

2001-01-01

259

Metals Verification Study for Sinclair and Dyes Inlets,Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington's 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. This Metals Verification Study was conducted to address the 303(d) segments that are listed for metal contaminants in marine sediment, because significant cleanup and source control activities have been conducted in the Inlets since the data supporting the 1998 303(d) listings were collected. The study was designed to obtain present-day sediment metals concentrations throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, with stations spatially distributed to support 303(d) listing updates and also watershed-level water quality and contaminant transport modeling efforts. A total of 160 surface sediment samples from Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage were screened for copper, lead, and zinc using X-Ray Fluorescence (XRF). 40 samples (25%) were selected for confirmatory metals analysis by ICP-MS for cadmium, silver, and arsenic in addition to copper, lead, and zinc. Regression relationships between the ICP-MS and XRF datasets were developed to estimate copper, lead, and zinc concentrations in all samples. The XRF results for copper, lead, and zinc correlated well with ICP-MS results, and predicted concentrations were calculated for all samples. The results of the Metals Verification Study show that sediment quality in Sinclair Inlet has improved markedly since implementation of cleanup and source control actions, and that the distribution of residual contaminants is limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard Superfund Site where further source control actions and monitoring are under way. Outside of Sinclair Inlet, the target metals met state sediment quality standards.

Kohn, Nancy P.; Miller, Martin C.; Brandenberger, Jill M.; Johnston, Robert K.

2004-09-29

260

Porous coolant tube holder for fuel cell stack  

DOEpatents

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

Guthrie, Robin J. (East Hartford, CT)

1981-01-01

261

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

262

Electro-impulse de-icing of a turbofan engine inlet  

NASA Technical Reports Server (NTRS)

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

Zumwalt, G. W.

1985-01-01

263

Sediment distribution and coastal processes in Cook Inlet, Alaska  

NASA Technical Reports Server (NTRS)

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

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

1973-01-01

264

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

265

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

266

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

267

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

268

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

269

The relationships between certain physical and chemical variables and the seasonal dynamics of phytoplankton assemblages of two inlets of a shallow hypertrophic lake with different nutrient inputs.  

PubMed

The relationships between water discharge, temperature, total dissolved solids (TDS) conductivity, turbidity, nitrate, ammonium, phosphate and the seasonal dynamics of phytoplankton assemblages of two inlets of a shallow hypertrophic lake (Lake Manyas, Turkey) were studied between January 2003 and December 2004. The results showed that different levels of water discharge, turbidity, conductivity, TDS and nutrients could lead to the development of significantly different phytoplankton assemblages in inlets of shallow hypertrophic lakes. The multiple regression analysis identified water discharge, turbidity and water temperature as the driving factors behind the dynamics of phytoplankton biovolume in the studied inlets. The first two axes of Canonical Correspondence Analysis (CCA) explained 78% of the total variance in dominant phytoplankton species at Si?irci Inlet and 88% at Kocaçay Inlet, respectively. The purpose of this study was to determine the relationships between water discharge, temperature, conductivity, turbidity, pH, TDS, nitrate, ammonium, phosphate and the seasonal dynamics of phytoplankton assemblages of two inlets of the shallow hypertrophic Lake Manyas, Turkey by means of multivariate statistical analysis. PMID:16897515

Celik, Kemal; Ongun, Tugba

2007-01-01

270

Organics Verification Study for Sinclair and Dyes Inlets, Washington  

SciTech Connect

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

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

2006-09-28

271

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

272

Testing of organic acids in engine coolants  

SciTech Connect

The effectiveness of 30 organic acids as inhibitors in engine coolants is reported. Tests include glassware corrosion of coupled and uncoupled metals. FORD galvanostatic and cyclic polarization electrochemistry for aluminum pitting, and reserve alkalinity (RA) measurements. Details of each test are discussed as well as some general conclusions. For example, benzoic acid inhibits coupled metals well but is ineffective on cast iron when uncoupled. In benzoic acid inhibits coupled metals well but is ineffective on cast iron when uncoupled. In general, the organic acids provide little RA when titrated to a pH of 5.5, titration to a pH of 4.5 can result in precipitation of the acid. Trends with respect to acid chain length are reported also.

Weir, T.W. [ARCO Chemical Co., Newtown Square, PA (United States)

1999-08-01

273

73. View of line of stainless steel coolant storage tanks ...  

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

73. View of line of stainless steel coolant storage tanks for bi-sodium sulfate/water coolant solution at first floor of transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

274

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

275

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

276

Effects of rotation on coolant passage heat transfer. Volume 1: Coolant passages with smooth walls  

NASA Technical Reports Server (NTRS)

An experimental program was conducted to investigate heat transfer and pressure loss characteristics of rotating multipass passages, for configurations and dimensions typical of modern turbine blades. The immediate objective was the generation of a data base of heat transfer and pressure loss data required to develop heat transfer correlations and to assess computational fluid dynamic techniques for rotating coolant passages. Experiments were conducted in a smooth wall large scale heat transfer model.

Hajek, T. J.; Wagner, J. H.; Johnson, B. V.; Higgins, A. W.; Steuber, G. D.

1991-01-01

277

Rapid Calculations of Three-Dimensional Inlet/Fan Interaction  

NASA Technical Reports Server (NTRS)

Two computational fluid dynamics codes have been merged to permit rapid calculations of inlet/fan interaction. Inlets are modeled using the WIND-US Navier-Stokes code. Fans are modeled using a new three-dimensional Euler code called CSTALL that solves the flow through the entire compression system but models blade rows using body forces for turning and loss. The body force model is described and it is shown how unknown terms in the model can be estimated from other Navier-Stokes solutions of the blade rows run separately. The inlet and fan calculations are run simultaneously and are coupled at an interface plane using a third code called SYNCEX that is described briefly. Results are shown for an axisymmetric nacelle at high angle of attack modeled both as an isolated inlet and coupled to a single stage fan. The isolated inlet calculations are unrealistic after the flow separates but the coupled codes can model large regions of separated flow extending from the lower lip of the nacelle into the fan rotor.

Chima, Rodrick V.

2007-01-01

278

Inlet distortion effects in aircraft propulsion system integration  

NASA Technical Reports Server (NTRS)

A tutorial survey of inlet flow distortion effects on engine performance and stability is presented. Inlet distortions in aero engines arise through a variety of causes. They can be essentially steady, due to non-axisymmetric intake duct geometry, or time varying, for example from flow separation off the lip of the inlet during maneuvers or shock-induced separation during supersonic flight. Whatever the cause, the result is generally a decrease in performance and, more importantly, a lessening of the stable flow range of the compressor. The distortions are generally three-dimensional. It is an extremely useful simplification to break them, at least conceptually, into radial and circumferential non-uniformities and approach each separately. Purely radial distortions can be treated by the methods that were developed for designing compressors in nominally axisymmetric inlet flow, and this type of distortion will be only briefly discussed. Circumferential non-uniformities, however, introduce additional fluid dynamic features into the analysis of compressor behavior and often have the larger impact on performance and stability. Thus we concentrate mainly on the effects of steady circumferential inlet flow distortion.

Longley, J. P.; Greitzer, E. M.

1992-01-01

279

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

280

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

281

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

282

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

283

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

284

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

285

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

286

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

287

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

288

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. Experimental results confirming the theoretical analysis give pressure recoveries which vary from 95 percent for Mach number 1.33 to 86 percent for number 2.00. These results were originally presented in a classified document of the NACA in 1946.

Ferri, Antonio; Nucci, Louis M

1952-01-01

289

Development of a three-dimensional supersonic inlet flow analysis  

NASA Technical Reports Server (NTRS)

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

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

1980-01-01

290

Two-Dimensional Inlet Simulation Using a Diagonal Implicit Algorithm  

NASA Technical Reports Server (NTRS)

A modification of an implicit approximate-factorization finite-difference algorithm applied to the two-dimensional Euler and Navier-Stokes equations in general curvilinear coordinates is presented for supersonic freestream flow about and through inlets. The modification transforms the coupled system of equations Into an uncoupled diagonal form which requires less computation work. For steady-state applications the resulting diagonal algorithm retains the stability and accuracy characteristics of the original algorithm. Solutions are given for inviscid and laminar flow about a two-dimensional wedge inlet configuration. Comparisons are made between computed results and exact theory.

Chaussee, D.S.; Pulliam, T. H.

1981-01-01

291

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

292

Seasonal variability of the suspended particulate matter concentration in Chupa Inlet of the White Sea  

NASA Astrophysics Data System (ADS)

Studies of the dynamics of the concentration of the suspended particulate matter (SPM) and Corg in the seawater of Chupa Inlet were performed for the three-year period of 2010-2012. In general, the concentration of SPM increased from the spring through the summer, decreased through the autumn period, and declined dramatically in the winter. The ratio of the organic matter in the SPM decreased gradually from the surface water layer to the bottom and averaged 61%. The abiotic factors affecting the SPM concentration and suspended organic matter were studied; the water temperature and tide events were named as the liming ones.

Mityaev, M. V.; Berger, V. Ya.

2014-05-01

293

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

294

Limits of sympathetic cooling of fermions: The role of heat capacity of the coolant  

NASA Astrophysics Data System (ADS)

The sympathetic cooling of an initially degenerate Fermi gas by either an ideal Bose gas below Tc or an ideal Boltzmann gas is investigated. It is shown that the efficiency of cooling by a Bose gas below Tc is by no means reduced when its heat capacity becomes much less than that of the Fermi gas, where efficiency is measured by the decrease in the temperature of the Fermi gas per number of particles evaporated from the coolant. This contradicts the intuitive idea that an efficient coolant must have a large heat capacity. In contrast, for a Boltzmann gas a minimal value of the ratio of the heat capacities is indeed necessary to achieve T=0 and all of the particles must be evaporated.

Carr, L. D.; Castin, Y.

2004-04-01

295

An LU implicity scheme for high speed inlet analysis  

NASA Technical Reports Server (NTRS)

A numerical method is developed to analyze the inviscid flowfield of a high speed inlet by the solution of the Euler equations. The lower-upper implicit scheme in conjunction with adaptive dissipation proves to be an efficient and robust nonoscillatory shock capturing technique for high Mach number flows as well as for transonic flows.

Yoon, S.; Jameson, A.

1986-01-01

296

Double inlet ventricle. Lung biopsy findings and implications for management  

Microsoft Academic Search

The lung was biopsied in 20 children with double inlet ventricle and pulmonary hypertension aged 2 months to 14 years. Eleven patients had two patent atrioventricular valves, three atresia of the right valve, and six hypoplasia of the left valve. Severe pulmonary arterial medial hypertrophy occurred in the nine children less than 1 year of age. The findings did not

E Juaneda; S G Haworth

1985-01-01

297

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

298

Hypersonic Magneto-Fluid-Dynamic Compression in Cylindrical Inlet  

NASA Technical Reports Server (NTRS)

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

Shang, Joseph S.; Chang, Chau-Lyan

2007-01-01

299

DETAILED NUMERICAL SIMULATIONS OF A SUPERSONIC INLET-ISOLATOR  

Microsoft Academic Search

An isolator is an important component of dual-mode scramjet engines that separates the combustor from the engine inlet. This ow section contains a time-varying shock- train that adapts to external variations in order to provide a stable ow to the combustion chamber. The goal of this study is to understand the key modeling issues in comput- ing the ow inside

Heeseok Koo; Venkatramanan Raman

300

Harvest History of Belugas, Delphinapterus leucas, in Cook Inlet, Alaska  

E-print Network

Alutiiq Eskimos and ers'recollections and interviews from only a Dena'ina Athabaskan Indians have long uti Century Alutiiq Eskimos and Dena'ina Atha baskan Indians have occupied the coast al areas surrounding Cook Inlet since prehistoric times (de Laguna, 1975). These hunting societies utilized many marine resources

301

Inlet and Propulsion Integration of Scram Propelled Vehicles  

NASA Technical Reports Server (NTRS)

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

Povinelli, Louis A.

1996-01-01

302

RECENT DEVELOPMENTS IN THE GEOMORPHIC INVESTIGATION OF ENGINEERED TIDAL INLETS  

Microsoft Academic Search

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

DUNCAN M. FITZGERALD; GARY A. ZARILLO

303

Low inlet gas velocity high throughput biomass gasifier  

DOEpatents

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

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

1989-01-01

304

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...

305

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 of 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. The results of this work were first presented in a classified document issued in 1946.

Ferri, Antonio; Nucci, Louis M

1951-01-01

306

Engine room, showing engine generator foundation and inlet louvers, looking ...  

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

Engine room, showing engine generator foundation and inlet louvers, looking southwest. Note fuel gauge on west wall, left of fuse box, and exhaust pipe through south wall. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

307

Dual inlet precision 13C analysis with multi-aliquot  

E-print Network

.02 per mil or better) Disadvantages of dual inlet IRMS · Requires extensive off line sample preparation of sample gas Disadvantages of continuous flow IRMS ·Relatively poor internal precision #12;Multi and Isoprime data taken from : Automated Analysis of 13C/12C ratios in CO2 and Dissolved Inorganic Carbon

308

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

309

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

310

Radiation effects in the stainless steel primary coolant supply adapter  

SciTech Connect

The primary coolant supply adapter (PCSA) is a flanged, cylindrical collar of 316NG stainless steel that is part of the primary pressure boundary of the Advanced Neutron Source. The radiation fluxes on the PCSA are dominated by thermal neutrons. During its intended 40-year service life, the PCSA will receive a thermal neutron fluence of 1.8 {times} 10{sup 26} m{sup {minus}2} in its upper sections at a temperature of <1OO{degree}C. The PCSA will suffer radiation damage, caused primarily by the interaction of thermal neutrons with the 14% nickel in the steel, which will generate helium by the sequential reactions {sup 58}Ni (n,y){sup 59}Ni (n,{alpha}){sup 56}Fe and will concurrently produce significant atomic displacements per atom (dpa) from the {sup 59}Ni (n,{alpha}){sup 56}Fe recoils. It is estimated that the helium concentration and total atomic displacements in the upper parts of the PCSA will be about 430 atomic parts per million and 1 dpa, respectively. From newly compiled trend curves of tensile properties and fracture toughness data versus atomic displacements for 316 steel, it is deduced that the irradiated PCSA will retain at least 20% uniform tensile elongation and a fracture toughness of more than 200 Mpa{radical}m, which are judged adequate to resist brittle failure. Tberefore, employment of a neutron shield around the PCSA is unnecessary.

Farrell, K.

1995-09-01

311

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

312

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...

313

Transient two-phase performance of LOFT reactor coolant pumps  

SciTech Connect

Performance characteristics of Loss-of-Fluid Test (LOFT) reactor coolant pumps under transient two-phase flow conditions were obtained based on the analysis of two large and small break loss-of-coolant experiments conducted at the LOFT facility. Emphasis is placed on the evaluation of the transient two-phase flow effects on the LOFT reactor coolant pump performance during the first quadrant operation. The measured pump characteristics are presented as functions of pump void fraction which was determined based on the measured density. The calculated pump characteristics such as pump head, torque (or hydraulic torque), and efficiency are also determined as functions of pump void fractions. The importance of accurate modeling of the reactor coolant pump performance under two-phase conditions is addressed. The analytical pump model, currently used in most reactor analysis codes to predict transient two-phase pump behavior, is assessed.

Chen, T.H.; Modro, S.M.

1983-01-01

314

CFD modeling of a gas turbine combustor from compressor exit to turbine inlet  

SciTech Connect

Gas turbine combustor CFD modeling has become an important combustor design tool in the past few years, but CFD models are generally limited to the flow field inside the combustor liner at the diffuser/combustor annulus region. Although strongly coupled in reality, the two regions have rarely been coupled in CFD modeling. A CFD calculation for a full model combustor from compressor diffuser exit to turbine inlet is described. The coupled model accomplishes the following two main objectives: (1) implicit description of flow splits and flow conditions for openings into the combustor liner, and (2) prediction of liner wall temperatures. Conjugate heat transfer with nonluminous gas radiation (appropriate for lean, low emission combustors) is utilized to predict wall temperatures compared to the conventional approach of predicting only near wall gas temperatures. Remaining difficult issues such as generating the grid, modeling swirler vane passages, and modeling effusion cooling are also discussed.

Crocker, D.S.; Nickolaus, D.; Smith, C.E. [CFD Research Corp., Huntsville, AL (United States)

1999-01-01

315

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

316

Experimental and Computational Evaluation of Flush-Mounted, S-Duct Inlets  

NASA Technical Reports Server (NTRS)

A new high Reynolds number test capability for boundary layer ingesting inlets has been developed for the NASA Langley Research Center 0.3-Meter Transonic Cryogenic Tunnel. Using this new capability. an experimental investigation of four S-duct inlet configurations was conducted. A computational study of one of the inlets was also conducted using a Navier-Stokes solver. The objectives of this investigation were to: 1) develop a new high Reynolds number inlet test capability for flush-mounted inlets; 2) provide a database for CFD tool validation; 3) evaluate the performance of S-duct inlets with large amounts of boundary layer ingestion; and 4) provide a baseline inlet for future inlet flow-control studies. Tests were conducted at Mach numbers from 0.25 to 0.83. Reynolds numbers (based on duct exit diameter) from 5.1 million to a full-scale value of 13.9 million, and inlet mass-flow ratios from 0.39 to 1.58 depending on Mach number. Results of the experimental study indicate that inlet pressure recovery generally decreased and inlet distortion generally increased with increasing Mach number. Except at low Mach numbers, increasing inlet mass-flow increased pressure recovery and increased distortion. Increasing the amount of boundary layer ingestion or ingesting a boundary layer with a distorted profile decreased pressure recovery and increased distortion. Finally, increasing Reynolds number had almost no effect on inlet distortion but increased inlet recovery by about one-half percent at a Mach number near cruise. The computational results captured the inlet pressure recovery and distortion trends with Mach number and inlet mass-flow well: the reversal of the pressure recovery trend with increasing inlet mass-flow at low and high Mach numbers was predicted by CFD. However, CFD results were generally more pessimistic (larger losses) than measured experimentally.

Berrier, Bobby L.; Allan, Brian G.

2004-01-01

317

Comparison of the Aeroacoustics of Two Small-Scale Supersonic Inlets  

NASA Technical Reports Server (NTRS)

An aerodynamic and acoustic investigation was performed on two small-scale supersonic inlets to determine which inlet would be more suitable for a High Speed Civil Transport (HSCT) aircraft during approach and takeoff flight conditions. The comparison was made between an axisymmetric supersonic P inlet and a bifurcated two-dimensional supersonic inlet. The 1/14 scale model supersonic inlets were used in conjunction with a 4.1 in (10.4 cm) turbofan engine simulator. A bellmouth was utilized on each inlet to eliminate lip separation commonly associated with airplane engine inlets that are tested under static conditions. Steady state measurements of the aerodynamic flowfield and acoustic farfield were made in order to evaluate the aeroacoustic performance of the inlets. The aerodynamic results show the total pressure recovery of the two inlets to be nearly identical, 99% at the approach condition and 98% at the takeoff condition. At the approach fan speed (60% design speed), there was no appreciable difference in the acoustic performance of either inlet over the entire 0 deg to 110 deg farfield measurement sector. The inlet flow field results at the takeoff fan speed (88% design speed), show the average inlet throat Mach number for the P inlet (Mach 0.52) to be approximately 2 times that of the 2D inlet (Mach 0.26). The difference in the throat Mach number is a result of the smaller throughflow area of the P inlet. This reduced area resulted in a 'soft choking' of the P inlet which lowered the tone and overall sound pressure levels of the simulator in the forward sector by an average of 9 dB and 3 dB, respectively, when compared to the 2D inlet.

Ng, Wing

1996-01-01

318

Numerical simulation of hypersonic inlet flows with equilibrium or finite rate chemistry  

NASA Technical Reports Server (NTRS)

An efficient numerical program incorporated with comprehensive high temperature gas property models has been developed to simulate hypersonic inlet flows. The computer program employs an implicit lower-upper time marching scheme to solve the two-dimensional Navier-Stokes equations with variable thermodynamic and transport properties. Both finite-rate and local-equilibrium approaches are adopted in the chemical reaction model for dissociation and ionization of the inlet air. In the finite rate approach, eleven species equations coupled with fluid dynamic equations are solved simultaneously. In the local-equilibrium approach, instead of solving species equations, an efficient chemical equilibrium package has been developed and incorporated into the flow code to obtain chemical compositions directly. Gas properties for the reaction products species are calculated by methods of statistical mechanics and fit to a polynomial form for C(p). In the present study, since the chemical reaction time is comparable to the flow residence time, the local-equilibrium model underpredicts the temperature in the shock layer. Significant differences of predicted chemical compositions in shock layer between finite rate and local-equilibrium approaches have been observed.

Yu, Sheng-Tao; Hsieh, Kwang-Chung; Shuen, Jian-Shun; Mcbride, Bonnie J.

1988-01-01

319

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

PubMed

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

Zhou, Qinghua; Wang, Weiguo; Cang, Huaiwen; Du, Yongzhai; Han, Fenglei; Chen, Chuang; Cheng, Shasha; Li, Jinghua; Li, Haiyang

2012-08-30

320

Additional testing of the inlets designed for a tandem fan V/STOL nacelle  

NASA Technical Reports Server (NTRS)

The wind tunnel testing of a scale model of a tandem fan nacelle designed for a type (subsonic cruise) V/STOL aircraft configuration is discussed. The performance for the isolated front inlet and for the combined front and aft inlets is reported. Model variables include front and aft inlets with aft inlet variations of short and long aft inlet cowls, with a shaft simulator and diffuser vortex generators, cowl lip fillets, and nacelle strakes. Inlet pressure recovery, distortion, and inlet angle-to-attack separation limits were evaluated at tunnel velocity from 0 to 240 knots, angles-of-attack from -10 to +40 degrees and inlet flow rates corresponding to throat Mach number from 0.0 to 0.6. Combined nacelle pitch and yaw runs up to 30 deg. were also made.

Ybarra, A. H.

1981-01-01

321

33 CFR 334.130 - Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va.; danger zone.  

Code of Federal Regulations, 2012 CFR

...Waters 3 2012-07-01 2012-07-01 false Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va...ZONE AND RESTRICTED AREA REGULATIONS § 334.130 Atlantic Ocean off Wallops Island and Chincoteague Inlet,...

2012-07-01

322

33 CFR 110.182 - Atlantic Ocean off Fort George Inlet, near Mayport, Fla.  

Code of Federal Regulations, 2011 CFR

...Waters 1 2011-07-01 2011-07-01 false Atlantic Ocean off Fort George Inlet, near Mayport, Fla. 110...ANCHORAGE REGULATIONS Anchorage Grounds § 110.182 Atlantic Ocean off Fort George Inlet, near Mayport, Fla....

2011-07-01

323

33 CFR 334.130 - Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va.; danger zone.  

Code of Federal Regulations, 2011 CFR

...Waters 3 2011-07-01 2011-07-01 false Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va...ZONE AND RESTRICTED AREA REGULATIONS § 334.130 Atlantic Ocean off Wallops Island and Chincoteague Inlet,...

2011-07-01

324

33 CFR 110.182 - Atlantic Ocean off Fort George Inlet, near Mayport, Fla.  

Code of Federal Regulations, 2012 CFR

...Waters 1 2012-07-01 2012-07-01 false Atlantic Ocean off Fort George Inlet, near Mayport, Fla. 110...ANCHORAGE REGULATIONS Anchorage Grounds § 110.182 Atlantic Ocean off Fort George Inlet, near Mayport, Fla....

2012-07-01

325

33 CFR 334.130 - Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va.; danger zone.  

Code of Federal Regulations, 2010 CFR

...Waters 3 2010-07-01 2010-07-01 false Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va...ZONE AND RESTRICTED AREA REGULATIONS § 334.130 Atlantic Ocean off Wallops Island and Chincoteague Inlet,...

2010-07-01

326

33 CFR 334.130 - Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va.; danger zone.  

Code of Federal Regulations, 2013 CFR

...Waters 3 2013-07-01 2013-07-01 false Atlantic Ocean off Wallops Island and Chincoteague Inlet, Va...ZONE AND RESTRICTED AREA REGULATIONS § 334.130 Atlantic Ocean off Wallops Island and Chincoteague Inlet,...

2013-07-01

327

33 CFR 110.182 - Atlantic Ocean off Fort George Inlet, near Mayport, Fla.  

Code of Federal Regulations, 2013 CFR

...Waters 1 2013-07-01 2013-07-01 false Atlantic Ocean off Fort George Inlet, near Mayport, Fla. 110...ANCHORAGE REGULATIONS Anchorage Grounds § 110.182 Atlantic Ocean off Fort George Inlet, near Mayport, Fla....

2013-07-01

328

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.  

Code of Federal Regulations, 2011 CFR

... Test procedure: Wind tunnel inlet aspiration test. 53.63 Section 53.63... Test procedure: Wind tunnel inlet aspiration test. (a) Overview. This...purpose of this test is to ensure that the aspiration of a Class II candidate...

2011-07-01

329

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

330

PTA test bed aircraft engine inlet model test report, revised  

NASA Technical Reports Server (NTRS)

The inlet duct test for the Propfan Testbed Assessment (PTA) program was completed in November 1984. The basic test duct was designed using the Lockheed QUADPAN computational code. Test objectives were to experimentally evaluate, modify as required, and eventually verify satisfactory performance as well as duct/engine compatibility. Measured total pressure recovery for the basic duct was 0.993 with no swirl and 0.989 for inflow with a 30 degree simulated swirl angle. This compared to a predicted recovery of 0.979 with no swirl. Measured circumferential distortion with swirl, based on a least-square curve fit of the data, was 0.204 compared to a maximum allowable value of 0.550. Other measured distortion parameters did as well or better relative to their respective maximum allowable values. The basic duct configuration with no refinements is recommended for the PTA inlet as a minimum cost installation.

Hancock, J. P.

1985-01-01

331

A modified two-stage pulse tube cryocooler utilizing double-inlet and multi-mesh regenerator  

NASA Astrophysics Data System (ADS)

In this paper a thermally coupled Stirling-type two-stage pulse tube cryocoolers (TSPTC) is studied using a one-dimensional (1-D) CFD code. After validating the results of the simulations, effects of synchronous utilization of multi-mesh regenerator and double-inlet on the performance of the TSPTC are investigated. Results of simulations show that non-oscillating friction factors do not possess sufficient accuracy for calculation of oscillating friction losses in non-porous media. Whereas, using oscillating friction factor of non-porous media leads to sufficient accurate results. According to the results, using multi-mesh regenerator and double-inlet increases the COP and decreases the minimum attainable temperature of the system. It is observed that a minimum temperature of 18.2 K is attainable using optimum multi-mesh regenerator and double-inlet; whereas, for a simple TSPTC with a uniform mesh regenerator, a minimum temperature of 26.4 K is concluded.

Arablu, M.; Jafarian, A.

2013-12-01

332

Membrane Inlet Mass Spectrometry for measuring dissolved gases  

SciTech Connect

A Membrane Inlet Mass Spectrometer (MIMS) is used to measure dissolved gas concentrations in environmental water samples. Gases are exsolved out of water by passing the sample through a silicone gas permeable membrane that is under vacuum. A quadrupole mass spectrometer attached to the vacuum system is capable of measuring a variety of gases over a wide range of concentration. The MIMS is a versatile and field portable instrument.

Singleton, M; Hudson, G

2005-08-10

333

Coal database for Cook Inlet and North Slope, Alaska  

USGS Publications Warehouse

This database is a compilation of published and nonconfidential unpublished coal data from Alaska. Although coal occurs in isolated areas throughout Alaska, this study includes data only from the Cook Inlet and North Slope areas. The data include entries from and interpretations of oil and gas well logs, coal-core geophysical logs (such as density, gamma, and resistivity), seismic shot hole lithology descriptions, measured coal sections, and isolated coal outcrops.

Stricker, Gary D.; Spear, Brianne D.; Sprowl, Jennifer M.; Dietrich, John D.; McCauley, Michael I.; Kinney, Scott A.

2011-01-01

334

In-Line Impactor Inlet for Bioaerosol Sampling  

Microsoft Academic Search

The proof of concept of a novel in-line real impactor (IRI) for preseparation of large particles in ambient inlets was demonstrated with a 1,250 L\\/min design. Numerical simulations predicted a cutpoint Stokes number 0.3 for a ratio of jet-to-plate spacing to jet width (S\\/W) of 2.0 and 0.5 for a ratio of 4.0. This variation in cutpoint Stokes number allows

Andrew R. McFarland; Shishan Hu; Michael M. Baehl; Kyle W. Richardson; Philip M. Poeschl

2011-01-01

335

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

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

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

336

Vortex tube can increase liquid hydrocarbon recovery at plant inlet  

Microsoft Academic Search

Use of a vortex-tube device yields improved inlet gas-liquid separation, when compared with a Joule-Thomson system, but is less costly and complex than a true isentropic system, such as a turboexpander. Because the vortex-tube unit provides separation as well as pressure reduction, the capital cost of a Joule-Thomson system with valve and separator will be similar to that of the

B. Hajdik; M. Lorey; J. Steinle; K. Thomas

1997-01-01

337

AERIAL SURVEYS OF BELUGAS IN COOK INLET, ALASKA, AUGUST 2007  

Microsoft Academic Search

The National Marine Fisheries Service (NMFS) conducted an aerial survey of the beluga population in northern Cook Inlet, Alaska, 1-2 August 2007. The 13.1 hour survey covered the coastal areas north of Moose Point and the Native Village of Tyonek. Consistent with NMFS surveys conducted since 1993, the August 2007 survey was flown in a high-wing, twin-engine aircraft (NOAA Twin

Kim E. W. Shelden; Kimberly T. Goetz; Julie A. Mocklin

338

Inlet Flow Control and Prediction Technologies for Embedded Propulsion Systems  

NASA Technical Reports Server (NTRS)

Fail-safe inlet flow control may enable high-speed cruise efficiency, low noise signature, and reduced fuel-burn goals for hybrid wing-body aircraft. The objectives of this program are to develop flow control and prediction methodologies for boundary-layer ingesting (BLI) inlets used in these aircraft. This report covers the second of a three year program. The approach integrates experiments and numerical simulations. Both passive and active flow-control devices were tested in a small-scale wind tunnel. Hybrid actuation approaches, combining a passive microvane and active synthetic jet, were tested in various geometric arrangements. Detailed flow measurements were taken to provide insight into the flow physics. Results of the numerical simulations were correlated against experimental data. The sensitivity of results to grid resolution and turbulence models was examined. Aerodynamic benefits from microvanes and microramps were assessed when installed in an offset BLI inlet. Benefits were quantified in terms of recovery and distortion changes. Microvanes were more effective than microramps at improving recovery and distortion.

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

2010-01-01

339

Volcanic tsunamis and prehistoric cultural transitions in Cook Inlet, Alaska  

NASA Astrophysics Data System (ADS)

The 1883 eruption of Augustine Volcano produced a tsunami when a debris avalanche traveled into the waters of Cook Inlet. Older debris avalanches and coeval paleotsunami deposits from sites around Cook Inlet record several older volcanic tsunamis. A debris avalanche into the sea on the west side of Augustine Island ca. 450 years ago produced a wave that affected areas 17 m above high tide on Augustine Island. A large volcanic tsunami was generated by a debris avalanche on the east side of Augustine Island ca. 1600 yr BP, and affected areas more than 7 m above high tide at distances of 80 km from the volcano on the Kenai Peninsula. A tsunami deposit dated to ca. 3600 yr BP is tentatively correlated with a southward directed collapse of the summit of Redoubt Volcano, although little is known about the magnitude of the tsunami. The 1600 yr BP tsunami from Augustine Volcano occurred about the same time as the collapse of the well-developed Kachemak culture in the southern Cook Inlet area, suggesting a link between volcanic tsunamis and prehistoric cultural changes in this region of Alaska.

Begét, James; Gardner, Cynthia; Davis, Kathleen

2008-10-01

340

Data base for the prediction of inlet external drag  

NASA Technical Reports Server (NTRS)

Results are presented from a study to define and evaluate the data base for predicting an airframe/propulsion system interference effect shown to be of considerable importance, inlet external drag. The study is focused on supersonic tactical aircraft with highly integrated jet propulsion systems, although some information is included for supersonic strategic aircraft and for transport aircraft designed for high subsonic or low supersonic cruise. The data base for inlet external drag is considered to consist of the theoretical and empirical prediction methods as well as the experimental data identified in an extensive literature search. The state of the art in the subsonic and transonic speed regimes is evaluated. The experimental data base is organized and presented in a series of tables in which the test article, the quantities measured and the ranges of test conditions covered are described for each set of data; in this way, the breadth of coverage and gaps in the existing experimental data are evident. Prediction methods are categorized by method of solution, type of inlet and speed range to which they apply, major features are given, and their accuracy is assessed by means of comparison to experimental data.

Mcmillan, O. J.; Perkins, E. W.; Perkins, S. C., Jr.

1980-01-01

341

Prediction of sound radiation from different practical jet engine inlets  

NASA Technical Reports Server (NTRS)

Computer codes which were based upon a special integral representation of the external solutions of the Helmholtz equation were upgraded so that they would yield accurate results for the acoustic radiation patterns in the field surrounding an axisymmetric body for nondimensional wave numbers, based on duct radius, of up to twenty. The accuracy of these computer programs was checked by the use of the point source method for the generation of exact solutions and then by comparison with the results of other experimental and theoretical studies. These computer codes were used in a parametric study of the dependence of the radiated sound field on input modal distribution, wave number, and inlet lip shape. The results of this study show that: (1) as the wave number (i.e., cut off ratio) is increased for a given input modal distribution that the acoustic radiation peak moves towards the inlet centerline and becomes more compact (i.e., narrows); (2) as the input mode number is increased for a given cut off ratio the acoustic radiation peak moves away from the inlet centerline and becomes more compact.

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

1982-01-01

342

Proceedings, 2001National Conference on Beach Preservation Technology, pp. 274-283 COASTAL INLET BANK EROSION  

E-print Network

erosion. These shorelines lie adjacent to coastal inlets and extend around the inlet from the ocean to bayProceedings, 2001National Conference on Beach Preservation Technology, pp. 274-283 COASTAL INLET BANK EROSION William C. Seabergh 1 Abstract: Much focus is placed on beach erosion on the open coast

US Army Corps of Engineers

343

Design and Numerical Investigation of Advanced Radial Inlet for a Centrifugal Compressor Stage  

Microsoft Academic Search

The performance of a centrifugal compressor stage can be seriously affected by inlet flow distortions due to an unsatisfactory inlet configuration and the resulting flow structure. In this study, two radial inlets were designed for a centrifugal compressor stage and investigated numerically using a commercially available 3D viscous Navier-Stokes code. The intent of the design was to minimize the total

Yunbae Kim; Jay Koch

344

Submitted to the AIAA Journal of Aircraft on April 1, 1996 High Performance Supersonic Missile Inlet  

E-print Network

Submitted to the AIAA Journal of Aircraft on April 1, 1996 High Performance Supersonic Missile, Connecticut 06180 April 1, 1996 Abstract A multi­level design strategy for supersonic missile inlet design­smooth design space. A geometry model for the supersonic missile inlet is developed. A supersonic missile inlet

Rasheed, Khaled

345

EBB-TIDAL DELTA DEVELOPMENT WHERE BEFORE THERE WAS NONE, SHARK RIVER INLET, NEW JERSEY  

E-print Network

458 EBB-TIDAL DELTA DEVELOPMENT WHERE BEFORE THERE WAS NONE, SHARK RIVER INLET, NEW JERSEY TANYA M.M.Beck@usace.army.mil. Abstract: The navigation channel at Shark River Inlet, NJ, is the responsibility of the U.S. Army Corps of Engineers, New York District. Until about the year 2000, the ocean entrance to Shark River Inlet required

US Army Corps of Engineers

346

FORTRAN program to generate engine inlet flow contour maps and distortion parameters  

NASA Technical Reports Server (NTRS)

A computer program is presented and described that generates jet engine inlet flow contour maps and inlet flow distortion parameters. The program input consists of an array of measurements describing the flow conditions at the engine inlet. User-defined distortion parameters may be calculated.

Dicus, J. H.

1974-01-01

347

ERTS-1 observations of sea surface circulation and sediment transport, Cook Inlet, Alaska  

NASA Technical Reports Server (NTRS)

Cook Inlet is a large tide-dominated estuary in southern Alaska. Highly turbid streams enter the upper inlet, providing an excellent tracer for circulation in the lower inlet. MSS 4 and 5 images both can be used in this area to plot sediment and pollutant trajectories, areas of (probable) commercial fish concentration, and the entire circulation regime.

Wright, F. F.; Sharma, G. D.; Burbank, D. C.

1973-01-01

348

An inlet\\/sampling duct for airborne OH and sulfuric acid measurements  

Microsoft Academic Search

An inlet assembly has been designed, tested, and used for the airborne measurements of OH and sulfuric acid. The inlet sampling duct, which incorporates a shroud connected to two nested, restricted flow ducts, slows air velocity by approximately a factor of 16 while maintaining a uniform and well-defined flow. Qualitative wind tunnel tests showed that an inlet shroud that incorporates

F. L. Eisele; R. L. Mauldin; D. J. Tanner; J. R. Fox; T. Mouch; T. Scully

1997-01-01

349

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

Code of Federal Regulations, 2011 CFR

...Midway Inlet, Pawleys Inlet, and North Inlet. (c) A line drawn...charted position of Winyah Bay North Jetty End Buoy 2N south to the Winyah Bay South Jetty...to Murphy Island. (f) A north-south line (longitude...

2011-07-01

350

Hypersonic mixed-compression inlet shock-induced combustion ramjets  

NASA Astrophysics Data System (ADS)

This study investigates the performance and flow field features of a mixed-compression inlet shock-induced combustion ramjet (shcramjet). In a shcramjet, oncoming air is compressed with shocks in the inlet and then further compressed and mixed with hydrogen fuel in a duct prior to shock-induced combustion and expansion of the combustion products through a divergent nozzle to provide thrust. Numerical studies are undertaken using the WARP code that solves the Favre-averaged Navier-Stokes equations closed by the Wilcox k-o turbulence model. Hydrogen/air combustion is solved via the twenty reaction, nine species combustion model of Jachimowski. Mixing augmentation through the use of cantilevered ramp injector arrays on opposite shcramjet inlet walls is studied and the influence of relative array locations is quantified. Increased spanwise distance between adjacent injectors on opposite walls allows for increased jet penetration and fuel distributions in the center of the engine duct. Chemically reacting studies verify an air buffer is created between the fuel and walls that suppresses premature ignition while still allowing for an air based mixing efficiency of up to 0.46-0.54. Combustion is produced over aerodynamic wedges with the spatial flow variation dictating both detonation and shock-induced combustion can be present over constant angle wedges. The initial inlet angle must be as high as possible, while avoiding premature ignition, to generate the pressure in the combustor needed for significant positive thrust. Thrust production from combustion is found to be insensitive to wedge angle if combustion is initiated across the cross-sectional area. Strong recirculation regions are formed via shock/boundary layer interactions in the confined engine duct. Mitigation of the recirculation is demonstrated with correct placement of the nozzle expansion in conjunction with air blowing in the boundary layer at a mass flow rate on the order of that of the fuel injection. For flight at Mach 11 the mixed-compression inlet shcramjet is found to generate a specific impulse of 683 s in the simulation of a realistic three-dimensional flow field.

Alexander, Derrick

351

CFD-Based Design Optimization Tool Developed for Subsonic Inlet  

NASA Technical Reports Server (NTRS)

The traditional approach to the design of engine inlets for commercial transport aircraft is a tedious process that ends with a less-than-optimum design. With the advent of high-speed computers and the availability of more accurate and reliable computational fluid dynamics (CFD) solvers, numerical optimization processes can effectively be used to design an aerodynamic inlet lip that enhances engine performance. The designers' experience at Boeing Corporation showed that for a peak Mach number on the inlet surface beyond some upper limit, the performance of the engine degrades excessively. Thus, our objective was to optimize efficiency (minimize the peak Mach number) at maximum cruise without compromising performance at other operating conditions. Using a CFD code NPARC, the NASA Lewis Research Center, in collaboration with Boeing, developed an integrated procedure at Lewis to find the optimum shape of a subsonic inlet lip and a numerical optimization code, ADS. We used a GRAPE-based three-dimensional grid generator to help automate the optimization procedure. The inlet lip shape at the crown and the keel was described as a superellipse, and the superellipse exponents and radii ratios were considered as design variables. Three operating conditions: cruise, takeoff, and rolling takeoff, were considered in this study. Three-dimensional Euler computations were carried out to obtain the flow field. At the initial design, the peak Mach numbers for maximum cruise, takeoff, and rolling takeoff conditions were 0.88, 1.772, and 1.61, respectively. The acceptable upper limits on the takeoff and rolling takeoff Mach numbers were 1.55 and 1.45. Since the initial design provided by Boeing was found to be optimum with respect to the maximum cruise condition, the sum of the peak Mach numbers at takeoff and rolling takeoff were minimized in the current study while the maximum cruise Mach number was constrained to be close to that at the existing design. With this objective, the optimum design satisfied the upper limits at takeoff and rolling takeoff while retaining the desirable cruise performance. Further studies are being conducted to include static and cross-wind operating conditions in the design optimization procedure. This work was carried out in collaboration with Dr. E.S. Reddy of NYMA, Inc.

1995-01-01

352

Coolant mixing and distribution in a transparent reactor model  

SciTech Connect

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 loop seal with steam generator and hot leg simulators completing the flow loop. Tests were conducted for a no-refill condition with constant liquid inventory in the facility and zero flow of the primary water. Salt water, dyed red was used for the coolant water to create prototypical density differences in this atmospheric facility. Steady state fluid distribution was determined from flow and density measurements and complete mass balances. Interpretation of the quantitative results was aided by extensive flow visualization studies which include still photographs and motion picture films for all tests. The test parameters included the fluid density ratio, the flow rate of coolant water, and the flow rate of primary water injected in the vessel downcomer to simulate a natural circulation flow through vent valves between the reactor core and the downcomer. Four locations of the small break were tested.

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

1983-11-01

353

Cladding embrittlement during postulated loss-of-coolant accidents.  

SciTech Connect

The effect of fuel burnup on the embrittlement of various cladding alloys was examined with laboratory tests conducted under conditions relevant to loss-of-coolant accidents (LOCAs). The cladding materials tested were Zircaloy-4, Zircaloy-2, ZIRLO, M5, and E110. Tests were performed with specimens sectioned from as-fabricated cladding, from prehydrided (surrogate for high-burnup) cladding, and from high-burnup fuel rods which had been irradiated in commercial reactors. The tests were designed to determine for each cladding material the ductile-to-brittle transition as a function of steam oxidation temperature, weight gain due to oxidation, hydrogen content, pre-transient cladding thickness, and pre-transient corrosion-layer thickness. For short, defueled cladding specimens oxidized at 1000-1200 C, ring compression tests were performed to determine post-quench ductility at {le} 135 C. The effect of breakaway oxidation on embrittlement was also examined for short specimens oxidized at 800-1000 C. Among other findings, embrittlement was found to be sensitive to fabrication processes--especially surface finish--but insensitive to alloy constituents for these dilute zirconium alloys used as cladding materials. It was also demonstrated that burnup effects on embrittlement are largely due to hydrogen that is absorbed in the cladding during normal operation. Some tests were also performed with longer, fueled-and-pressurized cladding segments subjected to LOCA-relevant heating and cooling rates. Recommendations are given for types of tests that would identify LOCA conditions under which embrittlement would occur.

Billone, M.; Yan, Y.; Burtseva, T.; Daum, R.; Nuclear Engineering Division

2008-07-31

354

Evaluation of Flush-Mounted, S-Duct Inlets With Large Amounts of Boundary Layer Ingestion  

NASA Technical Reports Server (NTRS)

A new high Reynolds number test capability for boundary layer ingesting inlets has been developed for the NASA Langley Research Center 0.3-Meter Transonic Cryogenic Tunnel. Using this new capability, an experimental investigation of four S-duct inlet configurations with large amounts of boundary layer ingestion (nominal boundary layer thickness of about 40% of inlet height) was conducted at realistic operating conditions (high subsonic Mach numbers and full-scale Reynolds numbers). The objectives of this investigation were to 1) develop a new high Reynolds number, boundary-layer ingesting inlet test capability, 2) evaluate the performance of several boundary layer ingesting S-duct inlets, 3) provide a database for CFD tool validation, and 4) provide a baseline inlet for future inlet flow-control studies. Tests were conducted at Mach numbers from 0.25 to 0.83, Reynolds numbers (based on duct exit diameter) from 5.1 million to a fullscale value of 13.9 million, and inlet mass-flow ratios from 0.39 to 1.58 depending on Mach number. Results of this investigation indicate that inlet pressure recovery generally decreased and inlet distortion generally increased with increasing Mach number. Except at low Mach numbers, increasing inlet mass-flow increased pressure recovery and increased distortion. Increasing the amount of boundary layer ingestion (by decreasing inlet throat height and increasing inlet throat width) or ingesting a boundary layer with a distorted profile decreased pressure recovery and increased distortion. Finally, increasing Reynolds number had almost no effect on inlet distortion but increased inlet recovery by about one-half percent at a Mach number near cruise.

Berrier, Bobby L.; Morehouse, Melissa B.

2003-01-01

355

Coherent lidar solution for the HSCT supersonic engine inlet unstart problem  

NASA Astrophysics Data System (ADS)

Atmospheric turbulence environments can adversely affect the operation of both commercial and military supersonic aircraft. Future aircraft designs, such as the High Speed Civil Transport will aim to alleviate the effects of supersonic engine inlet unstart. Fluctuations in air temperature, longitudinal and transverse velocity all can trigger inlet unstarts. With fore- knowledge of the turbulence, a feed-forward control system can be used to re-configure the propulsion systems to avoid unstarts. The same technology can be used to counteract gust effects to improve ride quality and reduce gust loads. A coherent lidar sensor is being developed to demonstrate that the atmospheric turbulence can be measured with sufficient reliability, fidelity, and pre-encounter time for these feed-forward control solutions. The NASA Airborne Coherent Lidar for Advanced In-flight Measurements (ACLAIM) program will develop and flight test a sensor on NASA research aircraft, including the SR-71, and investigate the atmospheric environment to establish the feasibility of a lidar sensor. The paper will present an overview of the ACLAIM program including: the scope and content of the program, lidar measurement challenges, atmospheric environment, technology choices, and anticipated problem areas.

Bogue, Rodney K.; Bagley, Harold R.; Soreide, David C.; Bowdle, David A.

1995-06-01

356

Experimental Measurement of Transonic Fan Wake Response to Uniform and Simulated Boundary Layer Ingesting Inlet Flows  

NASA Technical Reports Server (NTRS)

BWB Aircraft with embedded engines and BLI inlets offer attractive advantages in terms of reduced noise from engines and increased range and fuel economy. The BLI inlet produces inlet distortion patterns that can reduce fan performance and stall margin, and can produce undesirable forced responses. Knowledge of the dynamic response of fan flow when subjected to flow distortions of the type produced by BLI inlets is important for the design of distortion tolerant fans. This project is investigating fan response to flow distortion by measuring the response of the fan of a JT15D engine to a flow pattern following the results of the NASA Inlet A BLI wind tunnel tests.

O'Brien, Walter F.; Ferrar, Anthony M.; Arend, David

2011-01-01

357

A Combined Experimental/Computational Investigation of a Rocket Based Combined Cycle Inlet  

NASA Technical Reports Server (NTRS)

A rocket based combined cycle inlet geometry has undergone wind tunnel testing and computational analysis with Mach 4 flow at the inlet face. Performance parameters obtained from the wind tunnel tests were the mass capture, the maximum back-pressure, and the self-starting characteristics of the inlet. The CFD analysis supplied a confirmation of the mass capture, the inlet efficiency and the details of the flowfield structure. Physical parameters varied during the test program were cowl geometry, cowl position, body-side bleed magnitude and ingested boundary layer thickness. An optimum configuration was determined for the inlet as a result of this work.

Smart, Michael K.; Trexler, Carl A.; Goldman, Allen L.

2001-01-01

358

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

359

Molten fuel/coolant interactions: Recent analysis of experiments  

SciTech Connect

If a complete failure of normal and emergency coolant flows occurs in a light water reactor, fission product decay would eventually cause melting of the reactor fuel, leading to contact with water. An energetic fuel/coolant interaction (steam explosion) may result. Experiments were performed at Sandia National Laboratories in which about5 to 20 kg of molten fuel simulant were delivered into water in which the water mass was 1.5 to 50 times greater than the fuel. These experiments in subcooled and saturated water showed that spontaneous explosions occurred over the range of water/fuel mass ratio and that in certain experiments multiple explosions occurred. The kinetic energy conversion ratio was <2%. A model is proposed to describe the fuel/coolant mixing process. The model is compared to these intermediate-scale experiments. Additional data analysis indicates that the steam explosion is affected by the mixing process.

Corradini, M.L.

1984-04-01

360

The nature and behavior of particulates in PWR primary coolant  

SciTech Connect

A study of particle size distributions, nature and behavior of insoluble species carried by PWR coolants has been carried out over a four year period in Belgian reactors. Comparative data was obtained by the use of improved sampling systems designed to overcome the inadequacies of standard facilities. Coolant data is presented from commissioning and early operation of new plant to that in established PWR circuits. Results arising from reactors transients are also included, which refer to shutdown and start-up phases, power changes and scram situations. The information obtained includes chemical and radiochemical characteristics of particulates and their contribution to total activity carried by reactor coolant. The implications for plant operations are discussed. 16 refs., 55 figs., 24 tabs.

Bridle, D.A.; Butter, K.R.; Cake, P.; Comley, G.C.W.; Mitchell, C.R. (AEA Technology, Winfrith (UK))

1989-12-01

361

Aerodynamic and Acoustic Performance of Two Choked-Flow Inlets Under Static Conditions  

NASA Technical Reports Server (NTRS)

Tests were conducted to determine the aerodynamic and acoustic performance of two choking flow inlets under static conditions. One inlet choked the flow in the cowl throat by an axial translation of the inlet centerbody. The other inlet employed a translating grid of airfoils to choke the flow. Both inlets were sized to fit a 13.97 cm diameter fan with a design weight flow of 2.49 kg/sec. The inlets were operated in both the choked and unchoked modes over a range of weight flows. Measurements were made of inlet pressure recovery, flow distortion, surface static pressure distribution, and fan noise suppression. Choking of the translating centerbody inlet reduced blade passing frequency noise by 29 db while yielding a total pressure recovery of 0.985. Noise reductions were also measured at 1/3-octave band center frequencies of 2500, 5000, and 20,000 cycles. The translating grid inlet gave a total pressure recovery of 0.968 when operating close to the choking weight flow. However, an intermittent high intensity noise source was encountered with this inlet that precluded an accurate measurement of inlet noise suppression.

Miller, B. A.; Abbott, J. M.

1972-01-01

362

Top-mounted inlet system feasibility for transonic-subsonic fighter aircraft applications  

NASA Technical Reports Server (NTRS)

To inlet flow field and engine inlet performance data for an advanced fighter aircraft configuration were obtained over the Mach 0.6 to 2.0 range. The studies not only provided extensive data for the baseline arrangement, but also evaluated the effects of key aircraft configuration variables (inlet location, canopy-dorsal integration, wing leading-edge extension planform area, and variable incidence canards) on top inlet performance. In order to set these data in the context of practical aircraft systems top inlet performance is compared with that of more conventional inlet/airframe integrations. The results of these evaluations show that, for the top inlet configuration tested, relatively good inlet performance and compatibility characteristics are maintained during subsonic and transonic maneuver. However, at supersonic speeds, flow expansion over the forebody and wings causes an increase in local inlet Mach number subsequently reduces inlet performance levels. These characteristics infer that although top inlets many not pose a viable design option for aircraft requiring a high degree of supersonic maneuverability, they have distinct promise for vehicles with subsonic and transonic maneuver capabilities.

Williams, T. L.; Hunt, B. L.; Smeltzer, D. B.; Nelms, W. P.

1981-01-01

363

Numerical investigation of supersonic flow breakdown at the inlet duct throttling  

NASA Astrophysics Data System (ADS)

The work presents the results of investigating the process of supersonic flow deceleration in a duct of the two-dimensional inlet throttled by variation of the outlet cross-sectional area. An inlet with three external compression shock waves designed for the freestream Mach number Md = 7 was considered as an example for the investigation. A one-dimensional analysis of the conditions for realization of the supersonic flow deceleration regimes in the inlet duct with two throats — in the inlet entrance and at the inlet duct outlet, has been carried out. The parametric numerical computations of two-dimensional inviscid or turbulent flows in the inlet were performed with the use of the Euler and Navier—Stokes codes of the program package FLUENT. The critical conditions for the nonuniform flow in the outlet throat bringing to choking the inlet duct were determined.

Gounko, Yu. P.; Mazhul, I. I.; Nurutdinov, V. I.

2014-04-01

364

Experimental Investigation of a Large-Scale Low-Boom Inlet Concept  

NASA Technical Reports Server (NTRS)

A large-scale low-boom inlet concept was tested in the NASA Glenn Research Center 8- x 6- foot Supersonic Wind Tunnel. The purpose of this test was to assess inlet performance, stability and operability at various Mach numbers and angles of attack. During this effort, two models were tested: a dual stream inlet designed to mimic potential aircraft flight hardware integrating a high-flow bypass stream; and a single stream inlet designed to study a configuration with a zero-degree external cowl angle and to permit surface visualization of the vortex generator flow on the internal centerbody surface. During the course of the test, the low-boom inlet concept was demonstrated to have high recovery, excellent buzz margin, and high operability. This paper will provide an overview of the setup, show a brief comparison of the dual stream and single stream inlet results, and examine the dual stream inlet characteristics.

Hirt, Stefanie M.; Chima, Rodrick V.; Vyas, Manan A.; Wayman, Thomas R.; Conners, Timothy R.; Reger, Robert W.

2011-01-01

365

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

366

Dynamics of suspended matter concentration in Chupa Inlet (Karelian Coast, the White Sea) in summer and autumn  

NASA Astrophysics Data System (ADS)

Studies on the water and suspended matter concentration dynamics were performed for the summer and autumn periods in Kruglaya Bay, Chupa Inlet (Karelian Coast, the White Sea). The tidal cycle appeared as the major factor defining the water salinity, temperature, and suspended matter concentration. The water temperature and suspended matter concentration increased during low tide, and the opposite pattern was observed for water salinity; all the processes were true for both surface and bottom water layers. Therefore, we conclude that major bulk of the allochtonous suspended matter is carried into the sea by the ebb stream.

Mityaev, M. V.; Gerasimova, M. V.

2010-11-01

367

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

NASA Technical Reports Server (NTRS)

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

Moore, Charles S; Collins, John H

1937-01-01

368

Satellite applications to a coastal inlet study, Clearwater Beach, Florida  

NASA Technical Reports Server (NTRS)

Two sets of LANDSAT magnetic tapes were obtained and displayed on the screen of an IMAGE 100 computer. Spectral analysis was performed to produce various signatures, their extent and location. Subsequent ground truth observations and measurements were gathered by means of hydrographic surveys and low-altitude aerial photography for interpretation and calibration of the LANDSAT data. Finally, a coastal engineering assessment based on the LANDSAT data was made. Recommendations to the City of Clearwater regarding the navigational channel alignment and dredging practice are presented in the light of the inlet stability.

Wang, Y. H.; Smutz, M.; Ruth, B. E.; Brooks, H. K.

1977-01-01

369

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

370

Antimony tartrate corrosion inhibitive composition for coolant systems  

SciTech Connect

An automobile coolant concentrate is described comprising (a) a liquid polyhydric alcohol chosen from the group consisting of ethylene glycol, propylene glycol, diethylene glycol and mixtures thereof, and (b) corrosion inhibitors in a corrosion inhibitory amount with respect to corrosion of lead-containing solders, the corrosion inhibitors comprising (i) an alkali metal antimony tartrate, and (ii) an azole compound.

Payerle, N.E.

1987-08-11

371

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...

372

37. Upper level, chromate tanks (formerly provided coolant to missile ...  

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

37. Upper level, chromate tanks (formerly provided coolant to missile guidance section, retractor cables for lock pin in front of ladder at left - Ellsworth Air Force Base, Delta Flight, Launch Facility, On County Road T512, south of Exit 116 off I-90, Interior, Jackson County, SD

373

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.

374

Air-liquid lubricant and coolant aerosols in machining  

Microsoft Academic Search

Three methods for the preparation and supply of the lubricant and coolant fluid are proposed here: the use of cold air from an eddy tube; spraying of a minimum quantity of mineral oil; and the combination of air?liquid aerosol from an eddy-type sprayer and cold air from an eddy tube. In Fig. 2, the results obtained by these methods are

N. E. Kurnosov; A. V. Tarnopol’skii

2007-01-01

375

Technical note Coolant void worth in fast breeder reactors  

E-print Network

Technical note Coolant void worth in fast breeder reactors and accelerator-driven transuranium and minor-actinide burners K. Tucek *, J. Wallenius, W. Gudowski Department of Nuclear and Reactor Physics as a function of fuel composition and core geometry for several model fast breeder reactors and accelerator

376

Internal Designs Application for Inlet and Nozzle Aeroperformance Improvement  

NASA Technical Reports Server (NTRS)

The following research results are based on development of an approach previously proposed by the authors for optimum nozzle design to obtain maximum thrust. The design was denoted a Telescope nozzle. A Telescope nozzle contains one or several internal designs of certain location, 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, recent experimental acoustic tests have discovered an essential noise reduction due to Telescope nozzles application. In this paper, some additional theoretical results are presented for Telescope nozzles and a similar approach is applied for aeroperformance improvement of a supersonic inlet. In addition, a classic gas dynamics problem of a similar supersonic flow into a plate has been analyzed. In some particular cases, new exact analytical solutions are obtained for a flow into a wedge with an oblique shock wave. Numerical simulations were conducted for supersonic flow into a divergent portion of a 2D or axisymmetric nozzle with several plane or conuical designs as well as into a 2D or axisymmetric supersonic inlet with a forebody. The 1st order Kryko-Godunov marching numerical scheme for inviscid supersonic flows was used. Several cases were tested using the NASA CFL3d code based on full Navier-Stokes equations. Numerical simulation results have confirmed essential benefits of Telescope design applications in propulsion systems.

Gilinsky, M.; Blankson, I. M.

2000-01-01

377

Internal Designs Application for Inlet and Nozzle Aeroperformance Improvement  

NASA Technical Reports Server (NTRS)

The following research results are based on development of an approach previously proposed by the authors for optimum nozzle design to obtain maximum thrust. The design was denoted a Telescope nozzle. A Telescope nozzle contains one or several internal designs of certain location, 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, recent experimental acoustic tests have discovered an essential noise reduction due to Telescope nozzles application. In this paper, some additional theoretical results are presented for Telescope nozzles and a similar approach is applied for aeroperformance improvement of a supersonic inlet. In addition, a classic gas dynamics problem of a similar supersonic flow into a plate has been analyzed. In some particular cases, new exact analytical solutions are obtained for a flow into a wedge with an oblique shock wave. Numerical simulations were conducted for supersonic flow into a 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 1st order Kryko-Godunov marching numerical scheme for inviscid supersonic flows was used. Several cases were tested using the NASA CFL3d code based on full Navier-Stokes equations. Numerical simulation results have confirmed essential benefits of Telescope design applications in propulsion systems.

Gilinsky, M.; Blankson, I. M.

2000-01-01

378

Internal Designs Application for Inlet and Nozzle Aeroperformance Improvement  

NASA Technical Reports Server (NTRS)

The following research results are based on development of an approach previously proposed by the authors for optimum nozzle design to obtain maximum thrust. The design was denoted a Telescope nozzle. A Telescope nozzle contains one or several internal designs of certain location, 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, recent experimental acoustic tests have discovered an essential noise reduction due to Telescope nozzles application. In this paper, some additional theoretical results are presented for Telescope nozzles and a similar approach is applied for aeroperformance improvement of a supersonic inlet. In addition, a classic gas dynamics problem of a similar supersonic flow into a plate has been analyzed. In some particular cases, new exact analytical solutions are obtained for a flow into a wedge with an oblique shock wave. Numerical simulations were conducted for supersonic flow into a 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 1st order Kryko-Godunov march- ing numerical scheme for inviscid supersonic flows was used. Several cases were tested using the NASA CFL3d code based on full Navier-Stokes equations. Numerical simulation results have confirmed essential benefits of Telescope design applications in propulsion systems.

Gilinsky, M.; Blankson, I. M.

2000-01-01

379

Theoretical evaluation of engine auxiliary inlet design for supersonic V/STOL aircraft  

NASA Technical Reports Server (NTRS)

A higher order panel method is used to evaluate the potential flow of a two dimensional supersonic V/STOL inlet. A non-symmetric analytical inlet model is developed to closely match a wind tunnel model. The analytical inlet is analyzed for flow characteristics around the lower cowl lip and auxiliary inlets. The results are obtained from the output of a computer program that is based on the Hess Panel Method which determines source strengths of panels distributed over a three dimensional body. The analytical model was designed for the implementation of drooped/translated cowl lip and auxiliary inlets as flow improvement concepts. A 40 or 70 degree droop lip can be incorporated on the inlet to determine if these geometry modifications result in flow improvements which may reduce the propensity for flow separation on the interior portion of the lip. Auxiliary inlets are employed to decrease the mass flow over the inlet lip. Thus, the peak flow velocity is reduced at the lip which also lessens the likelihood of flow separation on the interior portion of the lip. A 2, 4, and 6 inch translated lip can be employed to also decrease mass flow over the inlet lower lip in the same manner as the auxiliary inlet. The performance results of the flow improvement concepts show that three possible inlet configurations provide a situation where separation is less likely to occur. A 70 degree droop lip maintains flow conditions such that attached flow over the lower cowl lip may exist for the entire angle of attack range studied. A 0 degree droop and translated lip combination provides similar results for the angle of attack range. The third configuration consists of a 0 degree droop and auxiliary inlet combination. This configuration provides slightly less favorable results than the other two, but still allows for conditions favorable to attached flow within the inlet.

Boles, Michael A.; Heavner, Richard L.

1988-01-01

380

Evaluation of Flush-Mounted, S-Duct Inlets with Large Amounts of Boundary Layer Ingestion  

NASA Technical Reports Server (NTRS)

A new high Reynolds number test capability for boundary layer ingesting inlets has been developed for the NASA Langley Research Center 0.3-Meter Transonic Cryogenic Tunnel. Using this new capability, an experimental investigation of four S-duct inlet configurations with large amounts of boundary layer ingestion (nominal boundary layer thickness of about 40% of inlet height) was conducted at realistic operating conditions (high subsonic Mach numbers and full-scale Reynolds numbers). The objectives of this investigation were to 1) provide a database for CFD tool validation on boundary layer ingesting inlets operating at realistic conditions and 2) provide a baseline inlet for future inlet flow-control studies. Tests were conducted at Mach numbers from 0.25 to 0.83, Reynolds numbers (based on duct exit diameter) from 5.1 million to a full-scale value of 13.9 million, and inlet mass-flow ratios from 0.39 to 1.58 depending on Mach number. Results of this investigation indicate that inlet pressure recovery generally decreased and inlet distortion generally increased with increasing Mach number. Except at low Mach numbers, increasing inlet mass-flow increased pressure recovery and increased distortion. Increasing the amount of boundary layer ingestion (by decreasing inlet throat height) or ingesting a boundary layer with a distorted (adverse) profile decreased pressure recovery and increased distortion. Finally, increasing Reynolds number had almost no effect on inlet distortion but increased inlet recovery by about one-half percent at a Mach number near cruise.

Berrier, Bobby L.; Morehouse, Melissa B.

2003-01-01

381

Overview of dye transport and mixing during RIVET at the New River Inlet  

NASA Astrophysics Data System (ADS)

Transport and mixing in a small tidal inlet (New River Inlet, NC, USA) was observed with fluorescent tracer dye during the ONR RIVET I experiment in May 2012. On each of 7 days, about 30 gallons of Rhodamine WT dye was released, either instantaneously or over several hours. Vertical dye concentration profiles were obtained with two wave-powered profilers, CTD+F casts, a boat-towed vertical fluorometer array, and an autonomous underwater vehicle. Dye concentrations were measured near the bottom with fixed instruments, and near the surface with two jet skis and airborne hyperspectral and multispectral imagers. Concurrent observations included waves, currents, turbidity, and water temperature and salinity. Ebb tidal currents were strong (1.5m/s) in two bathymetric channels (one newly dredged). Local wind and waves ranged from calm to moderate. Dye evolution depended on the dye release location, tide stage and wave and wind fields. Dye released continuously during ebb sometimes formed a surface plume that was visible several km downdrift from the mouth. Dye sometimes spread across the ebb shoal, where wave breaking was significant (the shoal was exposed at low tide). On the inner shelf, the thickness of the surface layer of bay water, slightly warmer and less saline than ocean water, varied from about 1m to 7m, depended on waves and wind. Dye behavior at New River will be compared with other tracers (e.g. CDOM, turbidity, temperature), and contrasted with previous observations of surfzone dye mixing and transport on an open coast with weak tidal currents. Funding was provided by the Office of Naval Research. .

Guza, R. T.; Feddersen, F.; Hally-Rosendahl, K.; Lenain, L.; Terrill, E.; Rogowski, P.; Statom, N.

2012-12-01

382

LOSS-OF-COOLANT ACIDENT SIMULATIONS IN THE NATIONAL RESEARCH UNIVERSAL REACTOR  

SciTech Connect

Pressurized water reactor loss-of-coolant accident (LOCA) phenomena are being simulated with a series of experiments in the U-2 loop of the National Research Universal Reactor at Chalk River, Ontario, Canada. The first of these experiments includes up to 45 parametric thermal-hydraulic tests to establish the relationship among the reflood delay time of emergency coolant, the reflooding rate, and the resultant fuel rod cladding peak temperature. Subsequent experiments establish the fuel rod failure characteristics at selected peak cladding temperatures. Fuel rod cladding pressurization simulates high burnup fission gas pressure levels of modern PWRs. This document contains both an experiment overview of the LOCA simulation program and a review of the safety analyses performed by Pacific Northwest Laboratory (PNL) to define the expected operating conditions as well as to evaluate the worst case operating conditions. The primary intent of this document is to supply safety information required by the Chalk River Nuclear Laboratories (CRNL), to establish readiness to proceed from one test phase to the next and to establish the overall safety of the experiment. A hazards review summarizes safety issues, normal operation and three worst case accidents that have been addressed during the development of the experiment plan.

Bennett, W D; Goodman, R L; Heaberlin, S W; Hesson, G M; Nealley, C; Kirg, L L; Marshall, R K; McNair, G W; Meitzler, W D; Neally, G W; Parchen, L J; Pilger, J P; Rausch, W N; Russcher, G E; Schreiber, R E; Wildung, N J

1981-02-01

383

Sedimentary architecture of a spit-end (Salisbury Beach, Massachusetts): The imprints of sea-level rise and inlet dynamics  

Microsoft Academic Search

In the vicinity of tidal inlets, the facies architecture of barrier islands is largely controlled by inlet channel shifting and the transfer of sand between the ebb-tidal delta and the adjacent shore, including processes of inlet sediment bypas sing. Merrimack River Inlet is situated in a mixed-energy setting and is characterized by episodic shifting of the ebb channel prior to

Susana Costas; Duncan FitzGerald

2011-01-01

384

Control Volume Analysis of Boundary Layer Ingesting Propulsion Systems With or Without Shock Wave Ahead of the Inlet  

NASA Technical Reports Server (NTRS)

The performance benefit of boundary layer or wake ingestion on marine and air vehicles has been well documented and explored. In this article, a quasi-one-dimensional boundary layer ingestion (BLI) benefit analysis for subsonic and transonic propulsion systems is performed using a control volume of a ducted propulsion system that ingests the boundary layer developed by the external airframe surface. To illustrate the BLI benefit, a relationship between the amount of BLI and the net thrust is established and analyzed for two propulsor types. One propulsor is an electric fan, and the other is a pure turbojet. These engines can be modeled as a turbofan with an infinite bypass ratio for the electric fan, and with a zero bypass ratio for the pure turbojet. The analysis considers two flow processes: a boundary layer being ingested by an aircraft inlet and a shock wave sitting in front of the inlet. Though the two processes are completely unrelated, both represent a loss of total pressure and velocity. In real applications, it is possible to have both processes occurring in front of the inlet of a transonic vehicle. Preliminary analysis indicates that the electrically driven propulsion system benefits most from the boundary layer ingestion and the presence of transonic shock waves, whereas the benefit for the turbojet engine is near zero or negative depending on the amount of total temperature rise across the engine.

Kim, Hyun Dae; Felder, James L.

2011-01-01

385

Modeling of small-scale single droplet fuel/coolant interactions  

SciTech Connect

In this paper a model for small-scale single droplet fuel/coolant interactions (FCIs) is proposed, which considers the growth of a coolant vapor/liquid interfacial disturbance into a coolant liquid jet during the collapse of the vapor film surrounding the fuel. This results in the encapsulation of the jet as coolant drops beneath the fuel surface and leads to fragmentation of the fuel. In this model, the FCI process is divided into four stages: film boiling around a molten fuel droplet in an infinite coolant pool, film collapse and coolant jet formation, coolant jet penetration and entrapment in the fuel, and rapid evaporation of entrained coolant and fragmentation of the fuel. The process repeats itself cyclically from the second stage. For the single-droplet experiments performed previously, the model predicts the qualitative trends of steam bubble growth and collapse, the final size of fuel fragments, and time scale for the fuel fragmentation.

Kim, B. (Hong-ik Univ., Seoul (Republic of Korea)); Corradini, M.L. (Wisconsin Univ., Madison, WI (USA). Dept. of Nuclear Engineering)

1988-01-01

386

MHTGR core temperature measurement trade study  

SciTech Connect

The objective of this task was to assess the need for core non-nuclear instrumentation. The focus of this study was the evaluation of core investment risk events. Three categories of events were considered: (1) unanticipated primary loop flow leakages and core bypass flows, (2) core coolant channel flow blockages and (3) off-design core power distributions. The measurements that were considered include column average coolant exit temperatures, core average coolant exit temperature, core pressure drop and core flow rate. The findings are summarized. 3 refs., 7 figs.

Kapernick, R.; Howard, W.

1989-09-29

387

Low-speed test of translating lip axisymmetric inlets for subsonic transports  

NASA Technical Reports Server (NTRS)

Translating lip, axisymmetric inlets have been tested at freestream Mach numbers between 0.0 and 0.30 and at angles of attack between 0 and 90 degrees. Three isolated inlet models were tested. One model represented the inlet geometry at cruise, that is, with no lip translation. The other two models had forward translating lips with different contours. The low forward speed inlet angle-of-attack capability with the translating lip was increased more than twenty degrees over the basic untranslated lip configuration at the higher inlet airflows. The static inlet performance with the translating lip was also greatly improved. The design translation distance, defined by potential flow analysis, was near optimum.

Henne, P. A.

1974-01-01

388

Aerodynamic and acoustic behavior of a YF-12 inlet at static conditions  

NASA Technical Reports Server (NTRS)

An aeroacoustic test program to determine the cause of YF-12 inlet noise suppression was performed with a YF-12 aircraft at ground static conditions. Data obtained over a wide range of engine speeds and inlet configurations are reported. Acoustic measurements were made in the far field and aerodynamic and acoustic measurements were made inside the inlet. The J-58 test engine was removed from the aircraft and tested separately with a bellmouth inlet. The far field noise level was significantly lower for the YF-12 inlet than for the bellmouth inlet at engine speeds above 5500 rpm. There was no evidence that noise suppression was caused by flow choking. Multiple pure tones were reduced and the spectral peak near the blade passing frequency disappeared in the region of the spike support struts at engine speeds between 6000 and 6600 rpm.

Bangert, L. H.; Feltz, E. P.; Godby, L. A.; Miller, L. D.

1981-01-01

389

On the inlet vortex system. [preventing jet engine damage caused by debris pick-up  

NASA Technical Reports Server (NTRS)

The flow field of a jet engine with an inlet vortex, which can pick up heavy debris from the ground and damage the engine, was simulated in a small water tunnel by means of the hydrogen bubble technique. It was found that the known engine inlet vortex is accompained by a vortex system, consisting of two inlet vortices (the ground based and the trailing one), secondary vortices, and ground vortices. Simulation of the ground effect by an inlet image proved that the inlet vortex feeds on free stream vorticity and can exist without the presence of a ground boundary layer. The structural form of the inlet vortex system was explained by a simple potential flow model, which showed the number, location, and the importance of the stagnation points. A retractable horizontal screen or an up-tilt of the engine is suggested as countermeasure against debris ingestion.

Bissinger, N. C.; Braun, G. W.

1974-01-01

390

Hydrodynamics of a small trained tidal inlet (Currumbin Creek, Australia)  

NASA Astrophysics Data System (ADS)

Small tidal inlets are important features of coastal areas, in terms of provision of access from a back barrier water-body to the ocean as well as periodic circulation of fresh nutrients for the local ecology. Usually, dimensional and geometrical characteristics contribute significantly to morphological stability or instability of a particular inlet and necessitate an individual investigation of any desired location. In other words, generalized usage of previous empirical and experimental research of a different position can hardly be used for other places. In this regard, one of the powerful tools to understand the physical processes of a particular region is to collect as much field data as possible. Such a dataset is used to further analyse and explore the governing processes and can also be used for building a numerical computer model for supplementary studies. In this research, the results of a comprehensive field measurement at Currumbin Creek, Queensland, Australia are presented. This study is part of broader research to investigate the long term evolution of the Currumbin entrance and its adjacent beaches. Currently, an annual dredging campaign is needed to reduce the risk of flooding due to excess rainfall inundations and to maintain water quality. The majority of data were collected over a three month period consistent with the time of the 2012 dredging operation. However, due to the loss of some instrumentation, data collection for some of the parameters was repeated till the middle of May 2013. All collected data included: (1) nearshore waves and tide; (2) creek tidal variation; (3) creek flow discharge and velocity; (4) bathymetric survey of the creek; (5) beach profile evolution survey; and (6) sediment sampling. The measurement showed that the creek entrance is tidally dominated, with flood events having a major role in sediment transport into the creek. The nearshore stations' wave data illustrated the marginal effect of the beach curvature between updrift and downdrift stations. Thus, the historical dataset available from the updrift wave rider buoy will be selected to be used for future numerical modelling. Although changes of some beach profiles were comparatively insignificant, the dramatic changes of the profile lines nearby the inlet channel and also rapid bathymetric change of the flood shoal following the dredging completion are valuable information to better calibrate and interpret a local sediment modelling study for the next phase. Essentially, this evaluation needs to be considered for proposing any alternative maintenance activities.

Shaeri, S.; Tomlinson, R. B.; Etemad-Shahidi, A.; Strauss, D.; Hughes, L. P.

2014-04-01

391

Development and Evaluation of a PM 10 Impactor-Inlet for a Continuous Coarse Particle Monitor  

Microsoft Academic Search

Conventional PM 10 inlets available operate at a flow rate of 16.7 l\\/min. The purpose of this study was to develop and test a PM 10 inlet designed to operate at 50 l\\/min to be used with a recently developed continuous coarse particle monitor (Misra et al.). Laboratory tests using polystyrene latex particles established the inlet's 50% cutpoint at 9.5

Chandan Misra; Michael D. Geller; Constantinos Sioutas; Paul A. Solomon

2003-01-01

392

Inlet Mode Transition Screening Test for a Turbine-Based Combined-Cycle Propulsion System  

Microsoft Academic Search

A combined computational and experimental study of inlet mode transition needed for Turbine-Based Combined-Cycle (TBCC) propulsion has been conducted. The Inlet Mode Transition Experiment (IMX) model used in this study is based on a careful design of an inlet system that supplies both a turbine engine and a ram\\/scramjet flowpath in an 'over\\/under' configuration. Traditional aerodynamic design techniques were used

J. D. Saunders; J. W. Slater; V. Dippold; J. Lee; B. W. Sanders; L. J. Weir

393

Effects of inlet geometries on flow recirculation in an axial-flow pump  

E-print Network

Committee: Dr. Peter Jenkins Experiments have been carried out in order to determine the effects of different inlet geometries on the onset of suction recircu- lation and its associated power consumption in axial flow pumps. The experiments were... were taken at different suction sections with varied flowrates to obtain the pumps' characteristic curves. Variations of the pump critical flowrate with different impeller inlet areas, suction piping and inlet guide vance were determined...

Alpan, Kenan

2012-06-07

394

Thermionic Converter Temperature Controller  

SciTech Connect

A method and apparatus for controlling the temperature of a thermionic reactor over a wide range of operating power, including a thermionic reactor having a plurality of integral cesium reservoirs, a honeycomb material disposed about the reactor which has a plurality of separated cavities, a solid sheath disposed about the honeycomb material and having an opening therein communicating with the honeycomb material and cavities thereof, and a shell disposed about the sheath for creating a coolant annulus therewith so that the coolant in the annulus may fill the cavities and permit nucleate boiling during the operation of the reactor.

Shaner,B. J.; Wolf, Joseph H.; Johnson, Robert G. R.

1999-08-23

395

Design, fabrication and measurement of a microchannel heat sink with a pin-fin array and optimal inlet position for alleviating the hot spot effect  

NASA Astrophysics Data System (ADS)

A microchannel heat sink with an inlet near the midpoint of the diagonal and high aspect ratio micro pin-fin array was designed, fabricated and measured. The heat transfer performance of the microchannel heat sink was simulated by a computational fluid dynamics (CFD) method. The inlet near the midpoint of the diagonal was proposed to alleviate the hot spot effect. The maximum temperature of the chip was reduced by up to 26.7% at a dissipation power of 72?W compared with other reference inlet/outlet configurations. Other parameters of the micro pin fins, such as the height, the spacing distance and the edge length, were optimized for improving heat transfer capacity. The microchannel heat sink prototype sample was fabricated and tested through UV-LIGA technology and an infrared thermal imaging system, respectively. The convective heat transfer increased at high flow rates (40?ml?min?1~90?ml?min?1), which resulted in a gradually increasing deviation between simulation and experiment. The measurement results show that the maximum dissipation heat flux can reach 209?W?cm?2 when the chip maximum temperature is under 85?°C at a flow rate of 90?ml?min?1. It is shown that the optimization of inlet position and micro pin-fin geometrical topology give the microchannel heat sink the potential to remove high heat flux.

Zhao, Junhong; Wang, Yan; Ding, Guifu; Sun, Yunna; Wang, Guilian

2014-11-01

396

Shock Position Control for Mode Transition in a Turbine Based Combined Cycle Engine Inlet Model  

NASA Technical Reports Server (NTRS)

A dual flow-path inlet for a turbine based combined cycle (TBCC) propulsion system is to be tested in order to evaluate methodologies for performing a controlled inlet mode transition. Prior to experimental testing, simulation models are used to test, debug, and validate potential control algorithms which are designed to maintain shock position during inlet disturbances. One simulation package being used for testing is the High Mach Transient Engine Cycle Code simulation, known as HiTECC. This paper discusses the development of a mode transition schedule for the HiTECC simulation that is analogous to the development of inlet performance maps. Inlet performance maps, derived through experimental means, describe the performance and operability of the inlet as the splitter closes, switching power production from the turbine engine to the Dual Mode Scram Jet. With knowledge of the operability and performance tradeoffs, a closed loop system can be designed to optimize the performance of the inlet. This paper demonstrates the design of the closed loop control system and benefit with the implementation of a Proportional-Integral controller, an H-Infinity based controller, and a disturbance observer based controller; all of which avoid inlet unstart during a mode transition with a simulated disturbance that would lead to inlet unstart without closed loop control.

Csank, Jeffrey T.; Stueber, Thomas J.

2013-01-01

397

Laboratory studies of eddy structures and exchange processes through tidal inlets  

E-print Network

with jetties with length longer than the inlet; and D) Inlet with a thicker barrier island with length longer than the width of the inlet. .............................17 Figure 5 Example of a result for the data analysis of and image for the Life... of the inlet. b) Longitudinal position of the center of the main vortex starting from the edge of the barrier island. c) Lateral position of the center of the main vortex starting from the edge of the barrier island. d) Circulation around the main vortex...

Nicolau del Roure, Francisco

2009-06-02

398

Analysis of a Channeled Centerbody Supersonic Inlet for F-15B Flight Research  

NASA Technical Reports Server (NTRS)

The Propulsion Flight Test Fixture at the NASA Dryden Flight Research Center is a unique test platform available for use on the NASA F-15B airplane, tail number 836, as a modular host for a variety of aerodynamics and propulsion research. The first experiment that is to be flown on the test fixture is the Channeled Centerbody Inlet Experiment. The objectives of this project at Dryden are twofold: 1) flight evaluation of an innovative new approach to variable geometry for high-speed inlets, and 2) flight validation of channeled inlet performance prediction by complex computational fluid dynamics codes. The inlet itself is a fixed-geometry version of a mixed-compression, variable-geometry, supersonic in- let developed by TechLand Research, Inc. (North Olmsted, Ohio) to improve the efficiency of supersonic flight at off-nominal conditions. The concept utilizes variable channels in the centerbody section to vary the mass flow of the inlet, enabling efficient operation at a range of flight conditions. This study is particularly concerned with the starting characteristics of the inlet. Computational fluid dynamics studies were shown to align well with analytical predictions, showing the inlet to remain unstarted as designed at the primary test point of Mach 1.5 at an equivalent pressure altitude of 29,500 ft local conditions. Mass-flow-related concerns such as the inlet start problem, as well as inlet efficiency in terms of total pressure loss, are assessed using the flight test geometry.

Ratnayake, Nalin A.

2010-01-01

399

Theoretical evaluation of engine auxiliary inlet design for supersonic V/STOL aircraft  

NASA Technical Reports Server (NTRS)

A higher order panel method is used to evaluate the potential flow of a 2-D supersonic V/STOL inlet. A nonsymmetric analytical inlet model is developed to closely match a wind tunnel model tested at NASA-Lewis. The analytical inlet used is analyzed for flow characteristics around the lower cowl lip and auxiliary inlets. The results for this analysis are obtained for the output of a computer program produced by the McDonnell Douglas Corp. This program is based on the Hess Panel Method which determines source strengths of panel distributed over a 3-D body. The analytical model was designed for the implementation of a drooped/translated cowl lip and auxiliary inlets as flow improvement concepts. A 40 or 70 deg droop lip can be incorporated on the inlet to determine if these geometry changes result in flow improvements which may reduce the propensity for flow separation on the interior portion of the lip. Auxiliary inlets are used to decrease the mass flow over the inlet lip; thus, the peak flow velocity is reduced at the lip which also lessens the likelihood of flow separation on the interior portion of the lip. A 2, 4, and 6 in. translated lip can be used to also decrease mass flow over the inlet lower lip in the same manner.

Boles, Michael A.; Heavner, Richard L.

1991-01-01

400

Experimental investigation of a 0.15-scale model of an underfuselage normal-shock inlet  

NASA Technical Reports Server (NTRS)

A 0.15 scale model of an underfuselage inlet designed for a single-engine fighter airplane was tested. The inlet was a fixed-geometry, normal-shock configuration designed to operate at flight speeds up to Mach 2.0. Peformance data for the basic inlet and several configuration variations are presented as a function of angle of attack, angle of sideslip, and airflow in the 0.6 to 2.0 Mach number range. The configuration variations included boundary-layer diverter height, cowl and splitter-plate modifications, and inlet bleed system variations. Flow-field characteristics at the simulated engine face, at the inlet throat, at the splitter-plate leading edge, and forward of the inlet are presented. The pressure recovery of the inlet is approximately equal to the product of theoretical normal-shock and duct pressure recoverable at cruise angle of attack. Very good performance at high angle of attack was obtained. Pressure distortion and turbulence at the engine face were low, and the inlet remained stable at all engine airflows over the flight maneuver envelope of the aircraft for which the inlet was designed.

Leamer, P. C.; Kennon, I. G.

1978-01-01

401

Inlet Shape Effects on the Far-Field Sound of a Model Fan  

NASA Technical Reports Server (NTRS)

A wind tunnel test was conducted to determine the effects of inlet shape on fan radiated noise. Four inlet geometries, which included a long standard flight type inlet, a short, aggressive flight inlet a scarf inlet, and an elliptical inlet were investigated in the study. The fan model used in the study was a 0.1 scale of the Pratt and Whitney Advanced Ducted Propeller (ADP), an ultra high bypass ratio turbofan engine. Acoustic data are presented for a fan speed of 70% (12,000 rpm) and a tunnel speed of 0.10 Mach number, The fan was configured with a 16-bladed rotor and a 40 stator vane set that were separated by 2.0 chord lengths. The radiated noise was measured with 15 microphones on a boom that traversed the length of the tunnel test section. Data from these microphones are presented in the form of sideline angle directivity plots. Noise associated with the test inlets was also predicted using a ray acoustics code. Inlet shape has been found to have a significant effect on both tone and broadband noise, and the non-axisymmetric inlet shape can be used for a noise reduction method.

Clark, L. R.; Thomas, R. H.; Dougherty, R. P.; Farassat, F.; Gerhold, C. H.

1997-01-01

402

Investigation of Methods for the Structural Weight Analysis of a Mach 2.4 Axisymmetric Inlet  

NASA Technical Reports Server (NTRS)

Structural design and analysis tools appropriate for estimating the structural weight of an axisymmetric inlet designed for Mach 2.4 cruise were evaluated. Little information regarding the inlet mechanical design is available in the preliminary design phase, so it is necessary to first develop a reasonable structural design before estimating the inlet weight. The Internally Pressurized Structure Synthesis and Optimization (IPSSO) program, employing an analytical approach, was chosen for evaluation due to its combined design and analysis capabilities. The inlet design produced by IPSSO was then analyzed using the NASTRAN finite element program. The finite element analysis was performed to help identify the limitations of the analytically based code as well as to evaluate NASTRAN for this application. Comparison between the IPSSO inlet weight and that of a similar inlet developed by the Boeing Commercial Airplane Group was also made. Program evaluation concluded that the combined use of IPSSO to create an initial design and NASTRAN to perform a numerical analysis would provide the capability to evaluate a limited number of inlet design The development of a new tool for the minimum weight design and analysis of inlet structures would be required for greater flexibility in evaluating inlet conceptual designs.

Nadell, Shari-Beth

1994-01-01

403

Visualizing supersonic inlet duct unstart using planar laser Rayleigh scattering  

NASA Astrophysics Data System (ADS)

Planar laser Rayleigh scattering (PLRS) from condensed CO2 particles is used to visualize flow structure in a Mach 5 wind tunnel undergoing unstart. Detailed flow features such as laminar/turbulent boundary layers and shockwaves are readily illustrated by the technique. A downstream transverse air jet, inducing flow unchoking downstream of the jet, is injected into the free stream flow of the tunnel, resulting in tunnel unstart. Time sequential PLRS images reveal that the boundary layer growth/separation on a surface with a thick turbulent boundary layer, initiated by the jet injection, propagates upstream and produces an oblique unstart shock. The tunnel unstarts upon the arrival of the shock at the inlet. In contrast, earlier flow separation on the opposite surface, initially supporting a thin laminar boundary layer, is observed when a jet induced bow shock strikes that surface. The resulting disturbance to this boundary layer also propagates upstream and precedes the formation of an unstart shock.

Do, Hyungrok; Im, Seong-Kyun; Mungal, M. Godfrey; Cappelli, Mark A.

2011-06-01

404

Mass independent kinetic energy reducing inlet system for vacuum environment  

DOEpatents

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

Reilly, Peter T.A.

2013-12-03

405

An Analysis of an Automatic Coolant Bypass in the International Space Station Node 2 Internal Active Thermal Control System  

NASA Technical Reports Server (NTRS)

A challenging part of International Space Station (ISS) thermal control design is the ability to incorporate design changes into an integrated system without negatively impacting performance. The challenge presents itself in that the typical ISS Internal Active Thermal Control System (IATCS) consists of an integrated hardware/software system that provides active coolant resources to a variety of users. Software algorithms control the IATCS to specific temperatures, flow rates, and pressure differentials in order to meet the user-defined requirements. What may seem to be small design changes imposed on the system may in fact result in system instability or the temporary inability to meet user requirements. The purpose of this paper is to provide a brief description of the solution process and analyses used to implement one such design change that required the incorporation of an automatic coolant bypass in the ISS Node 2 element.

Clanton, Stephen E.; Holt, James M.; Turner, Larry D. (Technical Monitor)

2001-01-01

406

92. View of transmitter building no. 102 first floor coolant ...  

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

92. View of transmitter building no. 102 first floor coolant process water tanks (sodium bisulfate solution), stainless steel, for electronic systems cooling in transmitter and MIP rooms. RCA Services Company 29 September, 1960, official photograph BMEWS Project by unknown photograph, Photographic Services, Riverton, NJ, BMEWS, clear as negative no. A-1226 - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

407

Expert system for online surveillance of nuclear reactor coolant pumps  

DOEpatents

An expert system for online surveillance of nuclear reactor coolant pumps. This system provides a means for early detection of pump or sensor degradation. Degradation is determined through the use of a statistical analysis technique, sequential probability ratio test, applied to information from several sensors which are responsive to differing physical parameters. The results of sequential testing of the data provide the operator with an early warning of possible sensor or pump failure.

Gross, Kenny C. (Bolingbrook, IL); Singer, Ralph M. (Naperville, IL); Humenik, Keith E. (Columbia, MD)

1993-01-01

408

Rotating solid radiative coolant system for space nuclear reactors  

SciTech Connect

The RING power system described in this paper is proposed as a primary or emergency heat rejection system for advanced space reactor power applications. The system employs a set of four (4) counter-rotating, 90 degree offset, coolant-carrying rings. The rings (segmented, corrugated, finned, thin-walled pipes, filled with liquid lithium) pass through a cavity heat exchanger and reradiate the absorbed heat to the space environment. 25 refs., 6 figs., 3 tabs.

Apley, W.J.; Babb, A.L.

1988-05-01

409

Experimental investigations of thermal interaction between corium and coolants  

NASA Astrophysics Data System (ADS)

We present a generalized analysis of the experimental results from investigations of thermal interaction in corium simulators (melts of thermite mixtures U + Mo3 and Zr + Fe2O3)-coolant (Na and H2O) systems. We also present the results from experimental assessments of the kinematic characteristics pertinent to the displacement of materials during the thermal interaction process and the coefficients for conversion of the corium thermal energy into mechanical work.

Zagorul'ko, Yu. I.; Zhmurin, V. G.; Volov, A. N.; Kovalev, Yu. P.

2008-03-01

410

Modelling physical effects of melt/coolant interaction  

SciTech Connect

The scripts of severe accidents in light water reactors, connected with molten fuel/coolant interaction (MCI) inside the vessel and in concrete well are analyzed. Physical model of thermal detonation is described. The list of initial data needed to calculate steam explosion and the ranges of their variation are analyzed. Estimations of the steam explosion intensity inside the vessel and in concrete well of WWER, as well as analysis of the factors determining the process are submitted. 8 figs.

Sorokin, A.P.; Bogatyrev, I.L. [Institute of Physics & Power Engineering, Obninsk (Russian Federation)

1997-12-01

411

Application technology progress report: Evaluation of PM-10 commercial inlets and development of an inlet for new Rocky Flats Plant surveillance air sampler, January 1986-December 1986  

SciTech Connect

Work during 1986 was concerned with developing a new PM-10 inlet for use at Rocky Flats Plant (RFP), Golden, Colorado. The commercial units that we evaluated did not allow for recovery of the >10-..mu..m dust fraction as may be required by EPA and DOE for nuclear installations. One of them, the Wedding PM-10 Inlet, did not meet the PM-10 cut-point requirement, because of the build-up of vegetative fibers in the cyclone type separator. Therefore, we developed a new PM-10 inlet (patent applied for) to meet our needs, and especially one that is adaptable to our existing 60 surveillance air samplers at minimum cost. The inlet utilizes a modified slotted impactor design. This device is directly adaptable to existing EPA high-volume samplers. 9 refs., 5 figs., 1 tab.

Langer, G.; Deitesfeld, C.A. (ed.0

1987-09-10

412

Application of CFX-10 to the Investigation of RPV Coolant Mixing in VVER Reactors  

SciTech Connect

Coolant mixing phenomena occurring in the pressure vessel of a nuclear reactor constitute one of the main objectives of investigation by researchers concerned with nuclear reactor safety. For instance, mixing plays a relevant role in reactivity-induced accidents initiated by de-boration or boron dilution events, followed by transport of a de-borated slug into the vessel of a pressurized water reactor. Another example is constituted by temperature mixing, which may sensitively affect the consequences of a pressurized thermal shock scenario. Predictive analysis of mixing phenomena is strongly improved by the availability of computational tools able to cope with the inherent three-dimensionality of such problem, like system codes with three-dimensional capabilities, and Computational Fluid Dynamics (CFD) codes. The present paper deals with numerical analyses of coolant mixing in the reactor pressure vessel of a VVER-1000 reactor, performed by the ANSYS CFX-10 CFD code. In particular, the 'swirl' effect that has been observed to take place in the downcomer of such kind of reactor has been addressed, with the aim of assessing the capability of the codes to predict that effect, and to understand the reasons for its occurrence. Results have been compared against experimental data from V1000CT-2 Benchmark. Moreover, a boron mixing problem has been investigated, in the hypothesis that a de-borated slug, transported by natural circulation, enters the vessel. Sensitivity analyses have been conducted on some geometrical features, model parameters and boundary conditions. (authors)

Moretti, Fabio; Melideo, Daniele; Terzuoli, Fulvio; D'Auria, Francesco [University of Pisa, Lungarno Pacinotti, 43 - 56126 Pisa (Italy)

2006-07-01

413

Crack stability analysis of low alloy steel primary coolant pipe  

SciTech Connect

At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

Tanaka, T.; Kameyama, M. [Kansai Electric Power Company, Osaka (Japan); Urabe, Y. [Mitsubishi Heavy Industries, Ltd., Takasago (Japan)] [and others

1997-04-01

414

Thermocouple based control rod position indication system  

SciTech Connect

This patent describes a rod position determination method. It comprises: measuring core coolant inlet temperature; measuring core coolant assembly exit temperature associated with a control rod; determining enthalpy rise from the inlet and exit temperature and a reference for an assembly containing the rod; determining the rod position charge; and determining the rod position from the rod position change and a reference rod position.

Heibel, M.D.; Impink, A.J. Jr.; Grobmyer, L.R.

1990-05-22

415

Thermocouple based control rod position indication system  

Microsoft Academic Search

This patent describes a rod position determination method. It comprises: measuring core coolant inlet temperature; measuring core coolant assembly exit temperature associated with a control rod; determining enthalpy rise from the inlet and exit temperature and a reference for an assembly containing the rod; determining the rod position charge; and determining the rod position from the rod position change and

M. D. Heibel; A. J. Jr. Impink; L. R. Grobmyer

1990-01-01

416

Application technology progress report: Evaluation of PM10 commercial inlets and development of an inlet for new Rocky Flats Plant surveillance air sampler, January 1986December 1986  

Microsoft Academic Search

Work during 1986 was concerned with developing a new PM-10 inlet for use at Rocky Flats Plant (RFP), Golden, Colorado. The commercial units that we evaluated did not allow for recovery of the >10-..mu..m dust fraction as may be required by EPA and DOE for nuclear installations. One of them, the Wedding PM-10 Inlet, did not meet the PM-10 cut-point

G. Langer; C. A. Deitesfeld

1987-01-01

417

Oceanographic conditions structure forage fishes into lipid-rich and lipid-poor communities in lower Cook Inlet, Alaska, USA  

USGS Publications Warehouse

Forage fishes were sampled with a mid-water trawl in lower Cook Inlet, Alaska, USA, from late July to early August 1996 to 1999. We sampled 3 oceanographically distinct areas of lower Cook Inlet: waters adjacent to Chisik Island, in Kachemak Bay, and near the Barren Islands. In 163 tows using a mid-water trawl, 229 437 fishes with fork length <200 mm were captured. More than 39 species were captured in lower Cook Inlet, but Pacific sand lance Ammodytes hexapterus, juvenile Pacific herring Clupea pallasi, and juvenile walleye pollock Theragra chalcogramma comprised 97.5% of the total individuals. Both species richness and species diversity were highest in warm, low-salinity, weakly stratified waters near Chisik Island. Kachemak Bay, which had thermohaline values between those found near Chisik Island and the Barren Islands, had an intermediate value of species richness. Species richness was lowest at the Barren Islands, an exposed region that regularly receives oceanic, upwelled water from the Gulf of Alaska. Non-metric multidimensional scaling (NMDS) was used to compute axes of species composition based on an ordination of pairwise site dissimilarities. Each axis was strongly rank-correlated with unique groups of species and examined separately as a function of environmental parameters (temperature, salinity, depth), area, and year. Oce??anographie parameters accounted for 41 and 12% of the variability among forage fishes indicated by Axis 1 and Axis 2, respectively. Axis 1 also captured the spatial variability in the upwelled area of lower Cook Inlet and essentially contrasted the distribution of species among shallow, nearshore (sand lance, herring) and deep, offshore (walleye pollock) habitats. Axis 2 captured the spatial variability in forage fish communities from the north (Chisik Island) to the south (Barren Islands) of lower Cook Inlet and essentially contrasted a highly diverse community dominated by salmonids and osmerids (warmer, less saline) with a fish community dominated by Pacific sand lance (colder, more saline). Axis 3 reflected the negative spatial association of capelin Mallotus villosus and Pacific cod Gadus macrocephalus. Correlations of year with Axes 1 and 3 indicate that from 1996 to 1999 the forage fish community significantly decreased in lipid-poor gadids (walleye pollock and Pacific cod), and significantly increased in lipid-rich species such as Pacific sand lance, Pacific herring, and capelin. ?? Inter-Research 2005.

Abookire, A. A.; Piatt, J. F.

2005-01-01

418

Oceanographic conditions structure forage fishes into lipid-rich and lipid-poor communities in lower Cook Inlet, Alaska, USA  

USGS Publications Warehouse

Forage fishes were sampled with a mid-water trawl in lower Cook Inlet, Alaska, USA, from late July to early August 1996 to 1999. We sampled 3 oceanographically distinct areas of lower Cook Inlet: waters adjacent to Chisik Island, in Kachemak Bay, and near the Barren Islands. In 163 tows using a mid-water trawl, 229437 fishes with fork length <200 mm were captured. More than 39 species were captured in lower Cook Inlet, but Pacific sand lance Ammodytes hexapterus, juvenile Pacific herring Clupea pallasi, and juvenile walleye pollock Theragra chalcogramma comprised 97.5% of the total individuals. Both species richness and species diversity were highest in warm, low-salinity, weakly stratified waters near Chisik Island. Kachemak Bay, which had thermohaline values between those found near Chisik Island and the Barren Islands, had an intermediate value of species richness. Species richness was lowest at the Barren Islands, an exposed region that regularly receives oceanic, upwelled water from the Gulf of Alaska. Non-metric multidimensional scaling (NMDS) was used to compute axes of species composition based on an ordination of pairwise site dissimilarities. Each axis was strongly rank-correlated with unique groups of species and examined separately as a function of environmental parameters (temperature, salinity, depth), area, and year. Oceanographic parameters accounted for 41 and 12% of the variability among forage fishes indicated by Axis 1 and Axis 2, respectively. Axis 1 also captured the spatial variability in the upwelled area of lower Cook Inlet and essentially contrasted the distribution of species among shallow, nearshore (sand lance, herring) and deep, offshore (walleye pollock) habitats. Axis 2 captured the spatial variability in forage fish communities from the north (Chisik Island) to the south (Barren Islands) of lower Cook Inlet and essentially contrasted a highly diverse community dominated by salmonids and osmerids (warmer, less saline) with a fish community dominated by Pacific sand lance (colder, more saline). Axis 3 reflected the negative spatial association of capelin Mallotus villosus and Pacific cod Gadus macrocephalus. Correlations of year with Axes 1 and 3 indicate that from 1996 to 1999 the forage fish community significantly decreased in lipid-poor gadids (walleye pollock and Pacific cod), and significantly increased in lipid-rich species such as Pacific sand lance, Pacific herring, and capelin.

Abookire, A. A.; Piatt, J. F.

2005-01-01

419

High Temperature Composite Heat Exchangers  

NASA Technical Reports Server (NTRS)

High temperature composite heat exchangers are an enabling technology for a number of aeropropulsion applications. They offer the potential for mass reductions of greater than fifty percent over traditional metallics designs and enable vehicle and engine designs. Since they offer the ability to operate at significantly higher operating temperatures, they facilitate operation at reduced coolant flows and make possible temporary uncooled operation in temperature regimes, such as experienced during vehicle reentry, where traditional heat exchangers require coolant flow. This reduction in coolant requirements can translate into enhanced range or system payload. A brief review of the approaches and challengers to exploiting this important technology are presented, along with a status of recent government-funded projects.

Eckel, Andrew J.; Jaskowiak, Martha H.

2002-01-01

420

Design of Modular, Shape-transitioning Inlets for a Conical Hypersonic Vehicle  

NASA Technical Reports Server (NTRS)

For a hypersonic vehicle, propelled by scramjet engines, integration of the engines and airframe is highly desirable. Thus, the forward capture shape of the engine inlet should conform to the vehicle body shape. Furthermore, the use of modular engines places a constraint on the shape of the inlet sidewalls. Finally, one may desire a combustor cross- section shape that is different from that of the inlet. These shape constraints for the inlet can be accommodated by employing a streamline-tracing and lofting technique. This design technique was developed by Smart for inlets with a rectangular-to-elliptical shape transition. In this paper, we generalise that technique to produce inlets that conform to arbitrary shape requirements. As an example, we show the design of a body-integrated hypersonic inlet on a winged-cone vehicle, typical of what might be used in a three-stage orbital launch system. The special challenge of inlet design for this conical vehicle at an angle-of-attack is also discussed. That challenge is that the bow shock sits relatively close to the vehicle body.

Gollan, Rowan J.; Smart, Michael K.

2010-01-01

421

Distribution of liquid sodium in the inlet plenum of steam generator in a Fast Breeder Reactor  

Microsoft Academic Search

Experimental and Computational Fluid Dynamics (CFD) investigations have been carried out on a 1\\/5th scale model of the inlet plenum of steam generator (SG) used in the Fast Breeder Reactor (FBR) technology. The distribution of liquid sodium in the inlet plenum of the steam generator strongly affects the thermal as well as mechanical performance of the steam generator. In the

Laxman T. Patil; A. W. Patwardhan; G. Padmakumar; G. Vaidyanathan

2010-01-01

422

COASTAL ENGINEERING 2012 DREDGING OPTIMIZATION OF AN INLET SYSTEM FOR ADJACENT SHORE  

E-print Network

COASTAL ENGINEERING 2012 1 DREDGING OPTIMIZATION OF AN INLET SYSTEM FOR ADJACENT SHORE PROTECTION of this study is to investigate optimal dredging volumes and intervals, and to determine the beach placement mining at St. Augustine Inlet over 1.4-year simulations. Results determined that dredging scenarios under

US Army Corps of Engineers

423

Conservation of threespine and ninespine stickleback radiations in the Cook Inlet Basin, Alaska  

Microsoft Academic Search

Summary Threespine stickleback (Gasterosteus aculeatus) and ninespine stickleback (Pungitius pun- gitius) are both species complexes with many unique and reproductively isolated biological species throughout their range. Both complexes exhibit phenomenal morphological and eco- logical diversity, including rare phenotypes, in the Cook Inlet Basin in Southcentral Alaska. The Cook Inlet threespine stickleback radiation has been used intensively since the early 1990s

Frank A. von Hippel

2008-01-01

424

Theoretical and experimental study of flow-control devices for inlets of indraft wind tunnels  

NASA Technical Reports Server (NTRS)

The design of closed circuit wind tunnels has historically been performed using rule of thumb which have evolved over the years into a body of useful guidelines. The development of indraft wind tunnels, however, has not been as well documented. The design of indraft wind tunnels is therefore generally performed using a more intuitive approach, often resulting in a facility with disappointing flow quality. The primary problem is a lack of understanding of the flow in the inlet as it passes through the required antiturbulence treatment. For wind tunnels which employ large contraction ratio inlets, this lack of understanding is not serious since the relatively low velocity of the flow through the inlet treatment reduces the sensitivity to improper inlet design. When designing a small contraction ratio inlet, much more careful design is needed in order to reduce the flow distortions generated by the inlet treatment. As part of the National Full Scale Aerodynamics Complex Modification Project, 2-D computational methods were developed which account for the effect of both inlet screens and guide vanes on the test section velocity distribution. Comparisons with experimental data are presented which indicate that the methods accurately compute the flow distortions generated by a screen in a nonuniform velocity field. The use of inlet guide vanes to eliminate the screen induced distortion is also demonstrated both computationally and experimentally. Extensions of the results to 3-D is demonstrated and a successful wind tunnel design is presented.

Ross, James C.

1989-01-01

425

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Test procedure: Wind tunnel inlet aspiration test. 53.63...PM2.5 § 53.63 Test procedure: Wind tunnel inlet aspiration test. (a...extracts an ambient aerosol at elevated wind speeds. This wind tunnel test uses...

2012-07-01

426

40 CFR 53.63 - Test procedure: Wind tunnel inlet aspiration test.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Test procedure: Wind tunnel inlet aspiration test. 53.63...PM 2.5 § 53.63 Test procedure: Wind tunnel inlet aspiration test. (a...extracts an ambient aerosol at elevated wind speeds. This wind tunnel test uses...

2013-07-01

427

Apparatus for controlling inlet air flow in a turbocharged internal combustion engine  

Microsoft Academic Search

This patent describes an apparatus for controlling inlet air flow in an internal combustion engine having a turbo-supercharger. The turbo-supercharge having a turbine driven by a pressure of an exhaust gas and an air compressor actuated by the turbine and connected to a combustion chamber of the engine through at least two intake passages so that inlet air compressed thereby

Mizutani

1988-01-01

428

Design and Wind Tunnel Study of a Top-mounted Diverterless Inlet  

Microsoft Academic Search

Combined with a UAV of the shape like Global Hawk, a new inlet is advanced to obtain high performance in both Radar Cross Section(RCS) and aerodynamic drag. Efforts are made to achieve this goal such as adopting a top-mounted inlet configuration, utilizing the diverterless technique and putting forward a new shape of entrance. A design method is brought forward and

Hui-jun TAN; Rong-wei GUO

2004-01-01