6,087 Matching Results

Search Results

Advanced search parameters have been applied.

Performance characteristics of aircraft cooling ejectors having short cylindrical shrouds

Description: The factors affecting the performance of ejector suitable for aircraft cooling are investigated theoretically and experimentally. The investigation covers a range of shroud-to-nozzle diameter ratios from 1.1 to 1.6, of shroud lengths from 0.2 to 2.28 nozzle diameters, of secondary-to-primary weight-flow ratios from 0 to 0.12, and of ambient-to-nozzle pressure ratios from 0.7 to 0.06. The results of a simplified theoretical analysis based on each type of flow are in good agreement with those experimentally obtained.
Date: May 22, 1951
Creator: Kochendorfer, Fred D. & Rousso, Morris D.
Partner: UNT Libraries Government Documents Department

High-Altitude Cooling 1: Resume of the Cooling Problem

Description: Report presenting a paper in a series about the cooling of aircraft-engine installations with special reference to the difficulties of cooling at high altitudes. This particular paper discusses the properties of NACA standard air and Army summer air, with corresponding stagnation conditions for a range of flight speed, as summarized in tables and figures.
Date: September 1944
Creator: Silverstein, Abe
Partner: UNT Libraries Government Documents Department

Investigation of Internal Film Cooling of 1000-Pound-Thrust Liquid-Ammonia - Liquid-Oxygen Rocket-Engine Combustion Chamber

Description: Memorandum presenting an investigation of internal film cooling of the combustion chamber of a 1000-pound-thrust liquid-ammonia-liquid-oxygen rocket engine. The three coolants studied were water, ethyl alcohol, and liquid ammonia. Results regarding heat-transfer results, liquid film-cooled length, correlation of heat-transfer data, and effect of film cooling on performance are provided.
Date: July 17, 1951
Creator: Morrell, Gerald
Partner: UNT Libraries Government Documents Department

Operating temperatures of a sodium-cooled exhaust valve as measured by a thermocouple

Description: Report presents the results of a thermocouple installed in the crown of a sodium-cooled exhaust valve. The valve was tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 degrees F. was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 r.p.m. Fuel-air ratio was found to have a large influence on valve temperature, but cooling-air pressure and variation in spark advance had little effect. An increase in engine power by change of speed or mean effective pressure increased the valve temperature. It was found that the temperature of the rear-spark-plug bushing was not a satisfactory indication of the temperature of the exhaust valve.
Date: 1943
Creator: Sanders, J. C.; Wilsted, H. D. & Mulcahy, B. A.
Partner: UNT Libraries Government Documents Department

Internal-liquid-film-cooling experiments with air-stream temperatures to 2000 degrees F. in 2- and 4-inch-diameter horizontal tubes

Description: Report presents the results of an investigation conducted to determine the effectiveness of liquid-cooling films on the inner surfaces of tubes containing flowing hot air. Experiments were made in 2- and 4-inch-diameter straight metal tubes with air flows at temperatures from 600 degrees to 2000 degrees F. and diameter Reynolds numbers from 2.2 to 14 x 10(5). The film coolant, water, was injected around the circumference at a single axial position on the tubes at flow rates from 0.02 to .24 pound per second per foot of tube circumference (0.8 to 12 percent of the air flow). Liquid-coolant films were established and maintained around and along the tube wall in concurrent flow with the hot air. The results indicated that, in order to film cool a given surface area with as little coolant flow as possible, it may be necessary to limit the flow of coolant introduced at a single axial position and to introduce it at several axial positions. The flow rate of inert coolant required to maintain liquid-film cooling over a given area of tube surface can be estimated when the gas-flow conditions are known by means of a generalized plot of the film-cooling data.
Date: May 27, 1952
Creator: Kinney, George R.; Abramson, Andrew E. & Sloop, John L.
Partner: UNT Libraries Government Documents Department

Analytical comparison of turbine-blade cooling systems designed for a turbojet engine operating at supersonic speed and high altitude 2: air-cooling systems

Description: Report presenting an investigation of the influence of high-altitude supersonic flight on the operation and effectiveness of turbine-blade air- and liquid-cooling systems for turbojet application in guided missiles and supersonic interceptor aircraft. Results regarding the coolant passage heat-transfer-coefficients, nonrefrigerated air-cooling-system characteristics, and refrigerated-air-cooling-system characteristics are provided.
Date: February 19, 1953
Creator: Schramm, Wilson B.; Arne, Vernon L. & Nachtigall, Alfred J.
Partner: UNT Libraries Government Documents Department

Antiproton stacking in the Recycler

Description: Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in double-row radial air-cooled engines 1: determination of cooling characteristics of flight engine

Description: Report discussing the cooling characteristics of a 14-cylinder double-row radial air-cooled engine in a four-engine airplane. The effects of charge-air flow, cooling-air pressure drop, and fuel-air ratio on the cooling characteristics were measured separately. The cooling equation, rear middle-barrel temperature, cooling-limited manifold pressure, and maximum cruising power versus temperature-limited power are described.
Date: December 20, 1944
Creator: Blackman, Calvin C.; White, H. Jack & Pragliola, Philip C.
Partner: UNT Libraries Government Documents Department

Effects of internal configuration on afterburner shell temperatures

Description: From Summary: "A brief investigation was conducted in the altitude wind tunnel to determine the extent to which the afterburner shell cooling problem could be alleviated by internal configuration changes. Data were obtained with and without a cooling liner installed and for variations in the radial fuel distribution and in the radial distribution in flame-seat area. Consideration is given to the effects on both shell temperature and afterburner performance."
Date: January 8, 1952
Creator: Conrad, E. William & Jansen, Emmert T.
Partner: UNT Libraries Government Documents Department

An Analytical Estimation of the Effect of Transpiration Cooling on the Heat-Transfer and Skin-Friction Characteristics of a Compressible, Turbulent Boundary Layer

Description: "An analysis based on mixing-length theory is presented which indicates that surface blowing associated with transpiration cooling systems produce large reductions in both the heat-transfer and skin-friction coefficients for a turbulent boundary layer on a flat plate. The numerical results are restricted to the case of air blowing into air. The effects of blowing are indicated to be similar for high-speed, compressible flow to those for low-speed, incompressible flow" (p. 1).
Date: December 1954
Creator: Rubesin, Morris W.
Partner: UNT Libraries Government Documents Department

Gas-turbine-engine performance when heat from liquid-cooled turbines is rejected ahead of, within, or behind main compressor

Description: Report discussing methods, advantages, and disadvantages of locating rotating heat exchangers ahead of, within, and behind the main engine compressor. Heat rejection should occur at the compressor discharge for best engine performance. Results regarding turbojet-engine performance, turboprop-engine performance, and a comparison of engine performance with liquid- and air-cooling are provided.
Date: May 22, 1956
Creator: Esgar, Jack B. & Slone, Henry O.
Partner: UNT Libraries Government Documents Department

Gas-to-blade heat-transfer coefficients and turbine heat-rejection rates for a range of one-spool cooled-turbine engine designs

Description: Report presenting gas-to-blade heat-transfer coefficients and turbine heat-rejection rates obtained for a wide range of one-spool turbojet engine designs believed to be representative of engines that will employ turbine cooling. The values of heat-transfer coefficient and heat-rejection rates are applicable to both liquid- and air-cooled turbines. Results regarding the heat-transfer coefficients and heat-rejection rates for turbojet engine designs, total heat-rejection rates for various turbojet engine and flight conditions, and heat-transfer coefficients and heat-rejection rates for turboprop engine design are provided.
Date: May 14, 1956
Creator: Slone, Henry O. & Esgar, Jack B.
Partner: UNT Libraries Government Documents Department

Effect of Air Cooling of Turbine Disk on Power and Efficiency of Turbine from Turbo Engineering Corporation TT13-18 Turbosupercharger

Description: "An investigation was conducted to determine the effect of turbine-disk cooling with air on the efficiency and the power output of the radial-flow turbine from the Turbo Engineering Corporation TT13-18 turbosupercharger. The turbine was operated at a constant range of ratios of turbine-inlet total pressure to turbine-outlet static pressure of 1,5 and 2.0, turbine-inlet total pressure of 30 inches mercury absolute, turbine-inlet total temperature of 12000 to 20000 R, and rotor speeds of 6000 to 22,000 rpm, Over the normal operating range of the turbine, varying the corrected cooling-air weight flow from approximately 0,30 to 0.75 pound per second produced no measurable effect on the corrected turbine shaft horsepower or the turbine shaft adiabatic efficiency" (p. 1).
Date: June 9, 1949
Creator: Berkey, William E.
Partner: UNT Libraries Government Documents Department

Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders covered a range in pitches from 0.057 to 0.25 inch average fin thicknesses from 0.035 to 0.04 inch, and fin widths from 0.67 to 1.22 inches" (p. 269).
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in modified double-row radial air-cooled engines 1: determination of the cooling characteristics of the flight engine

Description: Report discussing the cooling characteristics of a modified 14-cylinder double-row radial air-cooled engine installed in a four-engine airplane at a pressure altitude of 7000 feet. Testing of the variable charge-air flow, variable cooling-air pressure drop, and variable fuel-air ratio was conducted. The cooling equation, temperature-limited performance, maximum engine temperatures, and other information predicted by calculations is described.
Date: July 9, 1945
Creator: Werner, Milton; Blackman, Calvin C. & White, H. Jack
Partner: UNT Libraries Government Documents Department

Exploratory investigation of transpiration cooling to alleviate aerodynamic heating on an 8 degree cone in a free jet at a Mach number of 2.05

Description: Report presenting testing of the effectiveness of transpiration cooling of an 8 degree total angle conical body with water removed onto the surface through a porous section near the nose. Results regarding a reference test without cooling, a cooling test with 0.010 pound of water per second, a cooling test with 0.0025 pound of water per second, a hypothesis of the phenomena of liquid transpiration cooling, water consumption are provided.
Date: September 14, 1953
Creator: O'Sullivan, William J.; Chauvin, Leo T. & Rumsey, Charles B.
Partner: UNT Libraries Government Documents Department

Flight test of a solid-fuel ramjet with the internal surface of the combustor air cooled

Description: Report presenting a flight investigation of a rocket-launched solid-fuel ram-jet engine designed to bypass cooling air around the fuel charge. The internally cooled combustor averted combustor burn-out during the flight test. Results regarding the net thrust coefficient, gross thrust coefficient, time history of the air specific impulse, and total fuel load are provided.
Date: July 3, 1956
Creator: Bartlett, Walter A., Jr.
Partner: UNT Libraries Government Documents Department

Internal-Film Cooling of Rocket Nozzles

Description: Experiments were conducted with 1000-pound-thrust rocket engine to determine feasibility of cooling convergent-divergent nozzle by internal film of water introduced at nozzle entrance. Water flow of 3 percent of propellant flow reduced heat flow into nozzle to 55 percent of uncooled heat flow. Introduction of water by porous ring before nozzle resulted in more uniform coverage of nozzle than water introduced by single arrangement of 36 jets directed along nozzle wall. Water flow through porous ring of 3.5 percent of propellant flow stabilized wall temperature in convergent section but did not adequately cool throat or divergent sections.
Date: June 8, 1948
Creator: Sloop, J. L. & Kinney, George R.
Partner: UNT Libraries Government Documents Department

Investigation of high-temperature operation of liquid-cooled gas turbines I: turbine wheel of aluminum alloy, a high-conductivity nonstrategic material

Description: Report presenting an investigation of turbine operating temperatures as affected by liquid cooling, especially if materials of high conductivity are used, at gas temperatures up to 1925 degrees Fahrenheit. Results regarding the statio heat-transfer rig and turbine rig are provided. The investigation showed that nonstrategic material such as aluminum alloy can be used in liquid-cooled turbine wheels at high gas temperatures.
Date: July 22, 1948
Creator: Kottas, Harry & Sheflin, Bob W.
Partner: UNT Libraries Government Documents Department

Initial experiments on the aerodynamic cooling associated with large-scale vortical motions in supersonic flow

Description: Report presenting a theory of reduction of convective heat transfer to a surface in supersonic flow by periodically imposing a large-scale vortical motion on the boundary layer and an experimental investigation of that theory. Results regarding the pulsating flow phenomena, heat-transfer characteristics, and aerodynamic characteristics are provided.
Date: March 8, 1955
Creator: Eggers, A. J., Jr. & Hermach, C. A.
Partner: UNT Libraries Government Documents Department

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

Description: From Summary: "An investigation was conducted to determine the coolant-flow distribution, the cylinder temperatures, and the heat rejections of the V-1650-7 engine . The tests were run a t several power levels varying from minimum fuel consumption to war emergency power and at each power level the coolant flows corresponded to the extremes of those likely to be encountered in typical airplane installations, A mixture of 30-percent ethylene glycol and 70-percent water was used as the coolant. The temperature of each cylinder was measured between the exhaust valves, between the intake valves, in the center of the head, on the exhaust-valve guide, at the top of the barrel on the exhaust side, and on each exhaust spark-plug gasket."
Date: May 23, 1947
Creator: Povolny, John H. & Bogdan, Louis J.
Partner: UNT Libraries Government Documents Department