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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

Performance of two air-cooled turbojet engines determined analytically from engine component performance for a range of cooling-air weight flows

Description: Report presenting an analysis of two turbojet engines, including the component performance of the compressors and turbines, in order to determine the effect on engine performance and operation of bleeding the compressor to furnish cooling air for the turbine rotor blades. Results regarding the compressor and turbine performance characteristics and engine performance characteristics are provided.
Date: February 18, 1954
Creator: Ziemer, Robert R.; Schafer, Louis J., Jr. & Heaton, Thomas R.
Partner: UNT Libraries Government Documents Department

The problem of cooling an air-cooled cylinder on an aircraft engine

Description: An analysis of the cooling problem has been to show by what means the cooling of an air-cooled aircraft engine may be improved. Each means of improving cooling is analyzed on the basis of effectiveness in cooling with respect to power for cooling. The altitude problem is analyzed for both supercharged and unsupercharged engines. The case of ground cooling is also discussed. The heat-transfer process from the hot gases to the cylinder wall is discussed on the basis of the fundamentals of heat transfer and thermodynamics. Adiabatic air-temperature rise at a stagnation point in compressible flow is shown to depend only on the velocity of flow.
Date: April 22, 1940
Creator: Brevoort, M. J. & Joyner, U. T.
Partner: UNT Libraries Government Documents Department

Exploratory investigation of transpiration cooling of a 40 degree double wedge using nitrogen and helium as coolants at stagnation temperatures of 1,295 to 2,910 degrees F

Description: Report presenting an investigation of transpiration cooling in a preflight jet model consisting of a double wedge of 40 degrees included angle with a porous stainless-steel specimen inserted flush with the top surface of the wedge. Nitrogen and helium were used as coolants and testing was conducted for flow rates ranging from about 0.03 to 0.30 percent of the local weight flow. The helium coolant required only about one-fourth to one-fifth the coolant flow weight as the nitrogen coolant for the same amount of heat-transfer reduction.
Date: August 1, 1957
Creator: Rashis, Bernard
Partner: UNT Libraries Government Documents Department

Feasibility of nose-cone cooling by the upstream ejection of solid coolants at the stagnation point

Description: Report presenting an investigation in a chemical jet at a stagnation temperature of 4,000 degrees Fahrenheit at a Mach number of 2.8 to determine the feasibility of cooling models by the ejection of a solid coolant at the stagnation point. A series of conical models were tested with glass, Lucite, nylon, Teflon, and Texolite rods as coolants. Results regarding the cooling properties of each of the materials are provided, and all materials performed adequately with the exception of Teflon.
Date: March 24, 1958
Creator: Kinard, William H.
Partner: UNT Libraries Government Documents Department

Full-scale tests of NACA cowlings

Description: A comprehensive investigation has been carried on with full-scale models in the NACA 20-foot wind tunnel, the general purpose of which is to furnish information in regard to the physical functioning of the composite propeller-nacelle unit under all conditions of take-off, taxiing, and normal flight. This report deals exclusively with the cowling characteristics under condition of normal flight and includes the results of tests of numerous combinations of more than a dozen nose cowlings, about a dozen skirts, two propellers, two sizes of nacelle, as well as various types of spinners and other devices.
Date: May 18, 1936
Creator: Theodorsen, Theodore; Brevoort, M. J. & Stickle, George W.
Partner: UNT Libraries Government Documents Department

Internal film cooling experiments in 4-inch duct with gas temperatures to 2000 degrees F

Description: Report presenting an investigation of the cooling effectiveness of water films on the inner surface of a well-insulated, 4-inch-diameter duct with air flowing through the duct at a range of temperature and Reynolds numbers. Results regarding the effect of the gas temperature and mass velocity on liquid-cooled length, effect of coolant flow on liquid-cooled length, and some suggestions for further investigation are provided. Equations for correlation are created from the data.
Date: September 21, 1950
Creator: Kinney, George R. & Sloop, John L.
Partner: UNT Libraries Government Documents Department

Preliminary Air-Flow and Thrust Calibrations of Several Conical Cooling-Air Ejectors with a Primary to Secondary Temperature Ratio of 1.0, 2: Diameter Ratios of 1.06 and 1.40

Description: From Summary: "An investigation was made of the performance of nine conical cooling-air ejectors at primary jet pressure ratios from 1 to 10, secondary pressure ratios to 4.0, and a temperature ratio of unity. This phase of the investigation was limited to conical ejectors having shroud exit to primary nozzle exit diameter ratios of 1.06 and 1.40, with several spacing ratios for each. The experimental results indicated that the pumping range and amount of cooling-air flow obtained with a 1.06 diameter ratio ejector were relatively small for cooling purposes but that the maximum possible thrust loss, which occurred with no secondary flow, was only 7 percent of convergent nozzle thrust. The 1.40 diameter ratio ejector produced a large cooling air flow and showed a possible thrust loss of 29.5 percent with no cooling air flow. Thrust gains were attained with ejectors of both diameter ratios at secondary pressure ratios greater than 1.0. The limiting primary pressure ratio below which an ejector can operate at a specific secondary pressure ratio (cut-off point) may be estimated for various flight conditions from data contained herein."
Date: August 12, 1952
Creator: Greathouse, W. K. & Hollister, D. P.
Partner: UNT Libraries Government Documents Department

A Preliminary Study of Ram-Actuated Cooling Systems for Supersonic Aircraft

Description: An analysis has been made of the characteristics of several cooling cycles suitable for cockpit cooling of supersonic aircraft. All the cycles considered utilize the difference between dynamic and ambient static pressure to actuate the cooling system and require no additional power source. The results of the study indicate that as flight speeds become greater, increasingly complex systems are required to reduce the altitudes above approximately 35,000 feet, a system composed of an externally loaded expansion turbine in conjunction with a supersonic diffuser would maintain tolerable ventilating air temperature, at least up to a flight Mach number of 2. The most complex system considered,composed of compressor, intercooler, and expansion turbine with the intercooler cooling air decreased in temperature by expansion through an auxiliary turbine is capable of maintaining a ventilation air temperature less than ambient temperature up to a flight Mach number of 3.7.
Date: April 29, 1947
Creator: Stalder, Jackson R. & Wadleigh, Kenneth R.
Partner: UNT Libraries Government Documents Department

Design charts for cross-flow tubular intercoolers charge-across-tube type

Description: Report presenting equations relating the various dimensions, air mass flow, and performance of a cross-flow tubular intercooler in which the charge flows across and the cooling air through the tubes. Design charts are presented from which the intercooler design characteristics and performance can be quickly determined.
Date: January 1941
Creator: Reuter, J. George & Valerino, Michael F.
Partner: UNT Libraries Government Documents Department

Design charts for cross-flow tubular intercoolers charge-through-tube type

Description: Report presenting equations relating the various dimensions, air weight flow, and performance of a cross-flow tubular intercooler in which the charge flows through and the cooling air across the tubes. A method of determining and presenting the performance of a given intercooler at various operating conditions is indicated. Results regarding the cooling effectiveness equation, effect of primary intercooler variables, design charts, effect of tube arrangement on intercooler characteristics, and performance charts are provided.
Date: July 1941
Creator: Reuter, J. George & Valerino, Michael F.
Partner: UNT Libraries Government Documents Department

Comparison of Intercooler Characteristics

Description: Report presenting a method of comparing the performance, weight, and general dimensional characteristics of intercoolers. The performance and dimensional characteristics covered in the comparisons include cooling effectiveness, pressure drops and weight flows of the charge and cooling air, power losses, volume, frontal area, and width.
Date: November 1942
Creator: Reuter, J. George & Valerino, Michael F.
Partner: UNT Libraries Government Documents Department

An investigation of diffuser-resistance combinations in duct systems

Description: Report presenting an investigation to determine the properties of diffuser-resistance combinations. The work applies to the design of airplane cooling ducts in which air is expanded in front of resistances, such as radiators, oil coolers, intercoolers, or the cylinders of an air-cooled engine.
Date: February 1942
Creator: McLellan, Charles H. & Nichols, Mark R.
Partner: UNT Libraries Government Documents Department

High-altitude flight cooling investigation of a radial air-cooled engine

Description: Report presenting an investigation of the cooling of an 18-cylinder, twin-row, radial, air-cooled engine in a high-performance pursuit airplane for variable engine and flight conditions at a range of altitudes to provide a basis for predicting high-altitude cooling performance from sea-level or low-altitude test results.
Date: August 1946
Creator: Manganiello, Eugene J.; Valerino, Michael F. & Bell, E. Barton
Partner: UNT Libraries Government Documents Department

An experimental investigation of rectangular exhaust-gas ejectors applicable for engine cooling

Description: "An experimental investigation of rectangular exhaust-gas ejector pumps was conducted to provide data that would serve as a guide to the design of ejector applications for aircraft engines with marginal cooling. The pumping characteristics of rectangular ejectors actuated by the exhaust of a single-cylinder aircraft engine were determined for a range of ejector mixing-section area from 20 to 50 square inches, over-all length from 12 to 42 inches, aspect ratio from 1 to 5, diffusing exit area from 20 to 81 square inches, and exhaust-nozzle aspect ratio from 1 to 42" (p. 161).
Date: May 1, 1944
Creator: Manganiello, Eugene J. & Bogatsky, Donald
Partner: UNT Libraries Government Documents Department

High-altitude flight cooling investigation of a radial air-cooled engine

Description: "An investigation of the cooling of an 18-cylinder, twin-row, radial, air-cooled engine in a high-performance pursuit airplane has been conducted for variable engine and flight conditions at altitudes ranging from 5000 to 35,000 feet in order to provide a basis for predicting high-altitude cooling performance from sea-level or low altitude experimental results. The engine cooling data obtained were analyzed by the usual NACA cooling-correlation method wherein cylinder-head and cylinder-barrel temperatures are related to the pertinent engine and cooling-air variables. A theoretical analysis was made of the effect on engine cooling of the change of density of the cooling air across the engine (the compressibility effect), which becomes of increasing importance as altitude is increased" (p. 267).
Date: May 9, 1946
Creator: Manganiello, Eugene J.; Valerino, Michael F. & Bell, E. Barton
Partner: UNT Libraries Government Documents Department

Cylinder-temperature correlation of a single-cylinder liquid-cooled engine

Description: "An analysis based on nonboiling forced-convection heat-transfer theory is made of the cooling processes in liquid-cooled engine cylinders. Semiempirical equations that relate the average head and barrel temperatures with the primary engine and coolant parameters are derived. A correlation method based on these equations is applied to data obtained from previously reported investigations, which were conducted over large ranges of engine and coolant conditions with two liquid-cooled cylinders using water and various aqueous ethylene glycol solutions as coolants" (p. 285)
Date: October 1, 1946
Creator: Pinkel, Benjamin; Manganiello, Eugene J. & Bernardo, Everett
Partner: UNT Libraries Government Documents Department

Piston temperatures in an air-cooled engine for various operating conditions

Description: As part of a program for the study of piston cooling, this report presents the results of tests conducted on a single-cylinder, air-cooled, carburetor engine to determine the effect of engine operating conditions on the temperatures at five locations on the piston.
Date: April 6, 1940
Creator: Manganiello, Eugene J.
Partner: UNT Libraries Government Documents Department

Rapid determination of core dimensions of crossflow gas-to-gas heat exchangers

Description: Report presenting a generalized procedure that permits a rapid determination of the core lengths of crossflow gas-to-gas heat exchangers. Some of the variables that must be prescribed include the inlet states of each fluid, the available pressure drops for each fluid, the required temperature change of one fluid, the fluid heat capacities, and the core configuration.
Date: December 1956
Creator: Diaguila, Anthony J. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Study of ram-air heat exchangers for reducing turbine cooling-air temperature of a supersonic aircraft turbojet engine

Description: 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.
Date: August 3, 1956
Creator: Diaguila, Anthony J.; Livingood, John N. B. & Eckert, Ernst R. G.
Partner: UNT Libraries Government Documents Department

The effect of altitude on cooling

Description: Report presenting variables that control the cooling of liquid-cooled and air-cooled engines and then to show by illustrations how either engine may be cooled at any desired altitude. Cooling was found to not be the limiting factor in the design of high-altitude airplanes and was also not found to be a valid reason for selecting either liquid- or air-cooled engines for high-altitude operation.
Date: March 1943
Creator: Brevoort, Maurice J.; Joyner, Upshur T. & Wood, George P.
Partner: UNT Libraries Government Documents Department

The reduction of nonuseful pressure losses on air-cooled engine cylinders by means of improved finning and baffling

Description: Report presenting an analysis of the pressure drop that is required to cool a typically baffled radial engine, which shows that a total pressure drop of 58 pounds per square foot is necessary at sea level and 112 pounds per square foot is required at an altitude of 40,000 feet.
Date: February 1943
Creator: Wood, George P.
Partner: UNT Libraries Government Documents Department

Pressure available for cooling with cowling flaps

Description: Report presents the results of a full-scale investigation conducted in the NACA 20-foot tunnel to determine the pressure difference available for cooling with cowling flaps. The flaps were applied to an exit slot of smooth contour at 0 degree flap angle. Flap angles of 0 degree, 15 degrees, and 30 degrees were tested. Two propellers were used; propeller c which has conventional round blade shanks and propeller f which has airfoil sections extending closer to the hub. The pressure available for cooling is shown to be a direct function of the thrust disk-loading coefficient of the propeller.
Date: May 9, 1940
Creator: Stickle, George W.; Naiman, Irven & Crigler, John L.
Partner: UNT Libraries Government Documents Department