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Exact solutions of laminar-boundary-layer equations with constant property values for porous wall with variable temperature

Description: From Summary: "Exact solution of the laminar-boundary-layer equations for wedge-type flow with constant property values are presented for transpiration-cooled surfaces with variable wall temperatures. The difference between wall and stream temperature is assumed proportional to a power of the distance from the leading edge. Solutions are given for a Prandtl number of 0.7 and ranges of pressure-gradient, cooling-air-flow, and wall-temperature-gradient parameters. Boundary-layer profiles, dimensionless boundary-layer thicknesses, and convective heat-transfer coefficients are given in both tabular and graphical form. Corresponding results for constant wall temperature and for impermeable surfaces are included for comparison purposes."
Date: July 15, 1954
Creator: Donoughe, Patrick L. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Permeability and Strength Measurements on Sintered, Porous, Hollow Turbine Blades Made by the American Electro Metal Corporation under Office of Naval Research Contract N-ONR-295 (01)

Description: From Summary: "An experimental investigation was made to determine the permeability and strength characteristics of a number of sintered, porous, hollow turbine rotor blades and to determine the effectiveness of the blade fabrication method on permeability control. The test blades were fabricated by the American Electro Metal Corporation under a contract with the Office of Naval Research, Department of the Navy, and were submitted to the NACA for testing. Of the 22 test blades submitted, ten were sintered but not coined, five were sintered and coined, and seven were sintered and not coined but contained perforated reinforcements integral with the blade shells. Representative samples of each group of blades were tested."
Date: November 9, 1954
Creator: Richards, Hadley T. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Analysis of spanwise temperature distribution in three types of air-cooled turbine blade

Description: From Summary: An approximate method for determining the allowable stress-limited blade-temperature distribution is included, with brief accounts of a method for determining the maximum allowable effective gas temperatures and the cooling-air requirements. Numerical examples that illustrate the use of the various temperature-distribution equations and of the nondimensional charts are also included.
Date: March 1, 1950
Creator: Livingood, John N. B. & Brown, W. Byron
Partner: UNT Libraries Government Documents Department

Cooling of Gas Turbines, 6, Computed Temperature Distribution Through Cross Section of Water-Cooled Turbine Blade

Description: A theoretical analysis of the cross-sectional temperature distribution of a water-cooled turbine blade was made using the relaxation method to solve the differential equation derived from the analysis. The analysis was applied to specific turbine blade and the studies icluded investigations of the accuracy of simple methods to determine the temperature distribution along the mean line of the rear part of the blade, of the possible effect of varying the perimetric distribution of the hot gas-to -metal heat transfer coefficient, and of the effect of changing the thermal conductivity of the blade metal for a constant cross sectional area blade with two quarter inch diameter coolant passages.
Date: May 1, 1947
Creator: Livingood, John N. B. & Sams, Eldon W.
Partner: UNT Libraries Government Documents Department

Cooling of Gas Turbines, 3, Analysis of Rotor and Blade Temperatures in Liquid-Cooled Gas Turbines

Description: A theoretical analysis of the radial temperature distribution through the rotor and constant cross sectional area blades near the coolant passages of liquid cooled gas turbines was made. The analysis was applied to obtain the rotor and blade temperatures of a specific turbine using a gas flow of 55 pounds per second, a coolant flow of 6.42 pounds per second, and an average coolant temperature of 200 degrees F. The effect of using kerosene, water, and ethylene glycol was determined. The effect of varying blade length and coolant passage lengths with water as the coolant was also determined. The effective gas temperature was varied from 2000 degrees to 5000 degrees F in each investigation.
Date: February 11, 1947
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Solutions of laminar-boundary-equations which result in specific-weight-flow profiles locally exceeding free-stream values

Description: Revised solutions of the laminar-boundary-layer equations for cases which involved cooling at the wall combined with large pressure gradients in the main stream produced specific-weight-flow profiles which locally exceeded free-stream values. Heat-transfer and friction coefficients, boundary-layer thicknesses, and velocity, temperature, and specific-weight-flow distributions resulting from the revised solutions are presented for Euler numbers of 0.5 and 1, stream-to-wall temperature ratios of 2 and 4, and cooling-air flow rates through porous walls designated by flow parameters of 0, -0.5, and -1.
Date: September 1952
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Method for calculation of laminar heat transfer in air flow around cylinders of arbitrary cross section (including large temperature differences and transpiration cooling)

Description: "The solution of heat-transfer problems has become vital for many aeronautical applications. The shapes of objects to be cooled can often be approximated by cylinders of various cross sections with flow normal to the axis as, for instance heat transfer on gas-turbine blades and on air foils heated for deicing purposes. A laminar region always exists near the stagnation point of such objects. A method previously presented by E. R. G. Eckert permits the calculation of local heat transfer around the periphery of cylinders of arbitrary cross section in the laminar region for flow of a fluid with constant property values with an accuracy sufficient for engineering purposes" (p. 223).
Date: March 19, 1952
Creator: Eckert, E. R. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Measurement of heat-transfer and friction coefficients for flow of air in noncircular ducts at high surface temperatures

Description: Report presenting measurements of average heat-transfer and friction coefficients obtained with air flowing through electrically heated ducts with square, rectangular, and triangular cross sections for a range of surface temperatures and Reynolds numbers. Results regarding heat balances, correlation of heat-transfer coefficients, correlation of friction coefficients, and correlation of peripheral temperature variations are provided.
Date: January 25, 1954
Creator: Lowdermilk, Warren H.; Weiland, Walter F., Jr. & Livingood, John N. B.
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

Summary of laminar-boundary-layer solutions for wedge-type flow over convection-and transpiration-cooled surfaces

Description: Report presenting a summary of exact solutions of the laminar-boundary-layer equations for wedge-type flow, which are useful in estimating heat transfer to arbitrarily shaped bodies like turbine blades. The solutions are determined for small Mach numbers and for two cases: small temperature changes in the boundary layer along a constant- and variable-temperature wall, and large temperature changes in the boundary layer along a constant-temperature wall. Results regarding boundary-layer profiles and friction and heat transfer are provided.
Date: December 1955
Creator: Livingood, John N. B. & Donoughe, Patrick L.
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

Cooling of gas-turbines 7: effectiveness of air cooling of hollow turbine blades with inserts

Description: Report presenting an analytical investigation to determine primarily the reduction in cooling-air requirement and the increase in effective gas temperature for the same quantity of cooling air resulting from the use of an insert in the cooling-air passage of a hollow air-cooled turbine blade.
Date: October 20, 1947
Creator: Bressman, Joseph R. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Analysis of temperature distribution in liquid-cooled turbine blades

Description: From Summary: "This report presents analytical methods for computing temperature distributions in liquid-cooled turbine blades, or in simplified shapes used to approximate sections of the blade. The individual analyses are first presented in terms of their mathematical development. Nondimensional charts to simplify some temperature-distribution calculations are also given."
Date: October 27, 1950
Creator: Livingood, John N. B. & Brown, W. Byron
Partner: UNT Libraries Government Documents Department

Calculations of Laminar Heat Transfer Around Cylinders of Arbitrary Cross Section and Transpiration-Cooled Walls with Application to Turbine Blade Cooling

Description: An approximate method for development of flow and thermal boundary layers in laminar regime on cylinders with arbitrary cross section and transpiration-cooled walls is obtained by use of Karman's integrated momentum equation and an analogous heat-flow equation. Incompressible flow with constant property values throughout boundary layer is assumed. Shape parameters for approximated velocity and temperature profiles and functions necessary for solution of boundary-layer equations are presented as charts, reducing calculations to a minimum. The method is applied to determine local heat-transfer coefficients and surface temperature-cooled turbine blades for a given flow rate. Coolant flow distributions necessary for maintaining uniform blade temperatures are also determined.
Date: September 24, 1951
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Design of two transpiration-cooled strut-supported turbine rotor blades

Description: Report presenting the design details of two transpiration-cooled strut-supported turbine rotor blades. One design uses a sintered blade shell while the other uses a wire blade shell. Ideal coolant flows were found for an effective gas temperature of 1425 degrees Fahrenheit, a coolant temperature of 180 degrees Fahrenheit, and a shell temperature of 600 degrees Fahrenheit.
Date: April 25, 1956
Creator: Prasse, Ernst I.; Livingood, John N. B. & Donoughe, Patrick L.
Partner: UNT Libraries Government Documents Department

Design procedure for transpiration-cooled strut-supported turbine rotor blades

Description: From Summary: "The procedure currently employed by the NACA Lewis Laboratory in the design of transpiration-cooled strut-supported turbine rotor blades is discussed. The strut is the internal blade supporting member and also serves to partition the blade into separate cooling-air passages. Orifices in the blade base, which meter the cooling-air to each internal passage, are used in conjunction with a constant chordwise permeability."
Date: December 19, 1955
Creator: Prasse, Ernst I. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Comparison of effectiveness of convection-, transpiration-, and film-cooling methods with air as coolant

Description: From Summary: "Various parts of aircraft propulsion engines that are in contact with hot gases often require cooling. Transpiration and film cooling, new methods that supposedly utilize cooling air more effectively than conventional convection cooling, have already been proposed. This report presents material necessary for a comparison of the cooling requirements of these three methods. Correlations that are regarded by the authors as the most reliable today are employed in evaluating each of the cooling processes."
Date: July 9, 1953
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Cooling of gas turbines 9: cooling effects from use of ceramic coatings on water-cooled turbine blades

Description: From Summary: "The hottest part of a turbine blade is likely to be the trailing portion. When the blades are cooled and when water is used as the coolant, the cooling passages are placed as close as possible to the trailing edge in order to cool this portion. In some cases, however, the trailing portion of the blade is so narrow, for aerodynamic reasons, that water passages cannot be located very near the trailing edge. Because ceramic coatings offer the possibility of protection for the trailing part of such narrow blades, a theoretical study has been made of the cooling effect of a ceramic coating on: (1) the blade-metal temperature when the gas temperature is unchanged, and (2) the gas temperature when the metal temperature is unchanged."
Date: October 13, 1948
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

One-dimensional calculation of flow in a rotating passage with ejection through a porous wall

Description: Report presenting a method that can be used to predict either the local permeability necessary for a prescribed distribution of the coolant flow or the coolant-flow distribution resulting from a prescribed local permeability. It is applied to a determination of conditions in rotating turbine blades with transpiration-cooled walls.
Date: March 1955
Creator: Eckert, E. R. G.; Livingood, John N. B. & Prasse, Ernst I.
Partner: UNT Libraries Government Documents Department

Method for calculation of heat transfer in laminar region of air flow around cylinders of arbitrary cross section (including large temperature differences and transpiration cooling)

Description: Report presenting a method permitting the calculation of local heat transfer around the periphery of cylinders of arbitrary cross section in the laminar region for flow of a fluid with constant property values with an accuracy sufficient for engineering purposes. The method is applied to circular and elliptic cylinders are the results are described.
Date: June 1952
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department

Free-convection effects on heat transfer for turbulent flow through a vertical tube

Description: Report presenting experimental heat-transfer data for the turbulent flow of fluids through stationary vertical tubes with both small and large length-to-diameter ratios compared for the case where the acceleration of gravity is opposite in direction to the mean velocity in the tube and where the heat flows from the tube wall into the fluid.
Date: December 1955
Creator: Eckert, E. R. G.; Diaguila, Anthony J. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department