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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

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

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

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

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.
Date: 1943
Creator: Sanders, J. C.; Wilsted, H. D. & Mulcahy, B. A.
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

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

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

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

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

Fuel Consumption Corrected for Cooling Drag of an Air-Cooled Radial Aircraft Engine at Low Fuel-Air Ratios and With Variable Spark Advance

Description: Report presenting results of tests conducted with an air-cooled, radial aircraft engine to determine the reduction in the brake specific fuel consumption that would result from operating with a very low fuel-air ratio and an increased spark advance. Computed values of the brake specific fuel consumption corrected for cooling-air drag are also given.
Date: February 1945
Creator: Munger, Maurice
Partner: UNT Libraries Government Documents Department

A Method for the Design of Cooling Systems for Aircraft Power-Plant Installations

Description: Report presenting a method of organizing design calculations for the cooling systems of aircraft power-plant installations for use by representatives of airplane and engine companies invited to participate in the NACA power-plant installation section.
Date: March 1942
Creator: Rubert, Kennedy F. & Knopf, George S.
Partner: UNT Libraries Government Documents Department

Effects of Nature of Cooling Surface on Radiator Performance

Description: This report discusses the effects of roughness, smoothness, and cleanness of cooling surfaces on the performance of aeronautic radiators, as shown by experimental work, with different conditions of surface, on (1) heat transfer from a single brass tube and from a radiator; (2) pressure drop in an air stream in a single brass tube and in a radiator; (3) head resistance of a radiator; and (4) flow of air through a radiator. It is shown that while smooth surfaces are better than rough, the surfaces usually found in commercial radiators do not differ enough to show marked effect on performance, provided the surfaces are kept clean.
Date: 1921
Creator: Parsons, S. R. & Kleinschmidt, R. V.
Partner: UNT Libraries Government Documents Department

Investigation of an Air-Cooled, Plug-Type, Variable-Area Exhaust Nozzle

Description: Memorandum presenting an investigation of the cooling requirements and internal thrust performance of an air-cooled, plug-type, variable-area exhaust nozzle in a turbojet engine afterburner over a range of exhaust-gas total temperatures and exhaust-nozzle pressure ratios.
Date: April 10, 1957
Creator: Smolak, G. R. & Koffel, W. K.
Partner: UNT Libraries Government Documents Department

Effect in Flight of the Propeller Cuffs and Spinner on Pressure Recovery in Front of a Double-Row Radial Aircraft Engine in a Twin-Engine Airplane

Description: Report presenting an investigation conducted with the propeller cuffs and spinner removed to determine their effect in flight on the pressure recovery of the cooling-air flow. Curves are presented to compare the pressure and temperature distribution over the front row of cylinders for flights with and without cuffs and spinner.
Date: March 1944
Creator: Ellisman, Carl
Partner: UNT Libraries Government Documents Department

Use of Aerodynamic Heating to Provide Thrust by Vaporization of Surface Coolants

Description: Note presenting an analysis of the propulsive thrust and specific impulse attainable by cooling aircraft surfaces with liquefied or solidified gases with vaporization temperatures lower than the equilibrium surface temperature. Use of coolant vaporization as the sole means of propulsion yields low specific impulses at low speeds.
Date: February 1954
Creator: Moeckel, W. E.
Partner: UNT Libraries Government Documents Department

Comparative Effectiveness of a Convection Type and a Radiation-Type Cooling Cap on a Turbosupercharger

Description: Note presenting an investigation to compare the effectiveness of two basic methods of cooling a turbosupercharger and to obtain data on the temperature level and distribution in the turbine wheel. Turbine-wheel temperatures were obtained for various conditions of cooling-air mass flow, exhaust-gas temperature, and exhaust-gas mass flow. Modified forms of the standard cooling caps were used to allow for the installation of temperature-measuring devices.
Date: June 1946
Creator: Hartwig, Frederick J., Jr.
Partner: UNT Libraries Government Documents Department

Correlation of Wright Aeronautical Corporation Cooling Data on the R-3350-14 Intermediate Engine and Comparison With Data From the Langley 16-Foot High-Speed Tunnel

Description: Report presenting a comparison of the cooling-test data obtained on the identical Wright R-3350-14 engine equipped with the same cooling pressure-tube installation. The comparison reveals the large difference in cooling pressure drop that may be obtained in different test installations with the identical engine and pressure-tube installation because of an injudicious choice of pressure-tube locations.
Date: January 1945
Creator: Pinkel, Benjamin & Rubert, Kennedy F.
Partner: UNT Libraries Government Documents Department

The Effect of Increased Cooling Surface on Performance of Aircraft-Engine Cylinders as Shown by Tests of the NACA Cylinder

Description: Report presenting a method of constructing fins of nearly optimum proportions to the point where a cylinder has been manufactured and tested. Data were obtained on cylinder temperature for a wide range of inlet-manifold pressures, engine speeds, and cooling-pressure differences. Results regarding cooling equations, cylinder-temperature relationships, and a comparison of three cylinder cooling performances are provided.
Date: July 1944
Creator: Schey, Oscar W.; Rollin, Vern G. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department