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Determination of elastic stresses in gas-turbine disks

Description: A method is presented for the calculation of elastic stresses in symmetrical disks typical of those of a high-temperature gas turbine. The method is essentially a finite-difference solution of the equilibrium and compatibility equations for elastic stresses in a symmetrical disk. Account can be taken of point-to-point variations in disk thickness, in temperature, in elastic modulus, in coefficient of thermal expansion, in material density, and in Poisson's ratio. No numerical integration or trial-and-error procedures are involved and the computations can be performed in rapid and routine fashion by nontechnical computers with little engineering supervision. Checks on problems for which exact mathematical solutions are known indicate that the method yields results of high accuracy. Illustrative examples are presented to show the manner of treating solid disks, disks with central holes, and disks constructed either of a single material or two or more welded materials. The effect of shrink fitting is taken into account by a very simple device.
Date: 1947
Creator: Manson, S. S.
Partner: UNT Libraries Government Documents Department

Analytical investigation of flow and heat transfer in coolant passages of free-convection liquid-cooled turbines

Description: From Introduction: "An analytical investigation of the problems arising in connection with this cooling method was conducted at the NACA Lewis laboratory and is presented herein. This analysis investigates: (1) the smallest diameter hole that can be made without endangering the circulation of the liquid, and (2) methods of improving the circulation in a small-diameter hole."
Date: July 18, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
Partner: UNT Libraries Government Documents Department

A metallurgical investigation of a contour-forged disc of EME alloy

Description: Report presenting a study of the properties of EME alloy in the form of contour-forged discs for the rotors of gas turbines. The investigation was undertaken because the properties of promising alloys are dependent to a considerable extent on the conditions of fabrication and the size and shape of the rotor discs introduced fabrication procedures for which information was not available. Results regarding hardness surveys, short-time tensile properties, rupture test characteristics, time-deformation characteristics, creep strengths, stability characteristics, and data from tests in other laboratories are provided.
Date: November 1948
Creator: Reynolds, E. E.; Freeman, J. W. & White, A. E.
Partner: UNT Libraries Government Documents Department

An investigation of the high-temperature properties of chromium-base alloys at 1350 F

Description: Report presenting data for alloys that can resist temperatures up to 1350 degrees Fahrenheit so that they can be used in gas turbines. The chromium-base alloys currently have certain severe limitations in their present state of development. However, considerable progress has been made in overcoming these difficulties and further improvement seems possible.
Date: May 1947
Creator: Freeman, J. W.; Reynolds, E. E. & White, A. E.
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

The application of high-temperature strain gauges to the measurements of vibratory stresses in gas-turbine buckets

Description: The feasibility of measuring the vibration in the buckets of a gas turbine under service conditions of speed and temperature was determined by use of a high temperature wire strain gauge cemented to a modified supercharger turbine bucket. A high-temperature wire strain gauge and the auxiliary mechanical and electrical equipment developed for the investigation are described.
Date: April 1947
Creator: Kemp, R. H.; Morgan, W. C. & Manson, S. S.
Partner: UNT Libraries Government Documents Department

Application of blade cooling to gas turbines

Description: From Summary: "A review of the status of the knowledge on turbine-blade cooling and a description of pertinent NACA investigations are presented. The current limitations in performance of uncooled and cooled engines are briefly discussed. Finally, the knowledge available and investigations to increase the knowledge on heat transfer, cooling-flow, and performance characteristics of cooled turbines are discussed."
Date: May 31, 1950
Creator: Ellerbrock, Herman H., Jr. & Schafer, Louis J., Jr.
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

Investigation of distribution of losses in a conservatively designed turbine

Description: "A primary objective of turbine research is to obtain information that will aid in the design of gas turbines for any given application with minimum losses. As part of a program to obtain such information, flow surveys downstream of both the stator and the rotor of an experimental turbine were made in order to obtain detailed information about the flow conditions and the losses within the machine. The single-stage, low-radius-ratio turbine studied is relatively conservative in design, having low rotor-inlet relative Mach number, low turning angle, and high reaction at the rotor-root section" (p. 1).
Date: March 16, 1953
Creator: Whitney, Rose L.; Heller, Jack A. & Hauser, Cavour H.
Partner: UNT Libraries Government Documents Department

An analytical method for evaluating factors affecting application of transpiration cooling to gas turbine blades

Description: From Introduction: "A survey of some of the advantages and problems associated with transpiration cooling of gas-turbine engines is given in reference 1, and its is shown therein that high pressure gradients around the periphery of gas-turbine blades require that the blade wall permeability be varied around the blade periphery in order for uniform cooling to be obtained over the entire blade surface. This fact is verified in experimental investigations of transpiration-cooled turbine blades mounted in a static cascade (references 2 and 3) where it is shown that although transpiration cooling results in extremely effective cooling in the midchord region of the blade, there are very large variations in the chordwise temperature distribution because of improper permeability variation."
Date: September 8, 1952
Creator: Esgar, Jack B.
Partner: UNT Libraries Government Documents Department

Design and Experimental Investigation of Light-Weight Bases for Air-Cooled Turbine Rotor Blades

Description: Memorandum presenting an investigation of the problem of air-cooled turbine rotor-blade weight reduction for aircraft gas turbines as part of the NACA turbine-cooling research program. A bulb-root-type blade-base design was achieved which utilized forming and brazing techniques in its manufacture and was combined with an axial-flow turbojet engine aerodynamic profile. Results regarding the sheet-metal bulb-root-type air-cooled base designs, air-cooled pinned-type base design, and some weight reduction considerations are provided.
Date: July 2, 1954
Creator: Freche, John C. & McKinnon, Roy A.
Partner: UNT Libraries Government Documents Department

Construction and Use of Charts in Design Studies of Gas Turbines

Description: "A method is presented for the computation and graphic representation of a series of possible turbine designs for any specific application. The use of a preliminary design chart is suggested for determining the number of stages and the effects of exit whirl and annular-area divergence on possible configurations. A specific design chart can then be made to aid in the study of the relations between turbine radius ratio, diameter, and significant design parameters such as Mach numbers, turning angles, and blade root stresses" (p. 1).
Date: July 1951
Creator: Alpert, Sumner & Litrenta, Rose M.
Partner: UNT Libraries Government Documents Department

Temperatures and Stresses on Hollow Blades For Gas Turbines

Description: "The present treatise reports on theoretical investigations and test-stand measurements which were carried out in the BMW Flugmotoren GMbH in developing the hollow blade for exhaust gas turbines. As an introduction the temperature variation and the stress on a turbine blade for a gas temperature of 900 degrees and circumferential velocities of 600 meters per second are discussed. The assumptions on the heat transfer coefficients at the blade profile are supported by tests on an electrically heated blade model" (p. 1).
Date: September 1947
Creator: Pollmann, Erich
Partner: UNT Libraries Government Documents Department

Cooling of Gas Turbines 1 - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

Description: "An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling arising from exposure of the outer blade flange and one face of the rotor to the air" (p. 1).
Date: February 11, 1947
Creator: Brown, W. Byron
Partner: UNT Libraries Government Documents Department

Determination of Stresses in Gas-turbine Disks Subjected to Plastic Flow and Creep

Description: From Summary: "A finite-difference method previously presented for computing elastic stresses in rotating disks is extended to include the computation of the disk stresses when plastic flow and creep are considered. A finite-difference method is employed to eliminate numerical integration and to permit nontechnical personnel to make the calculations with a minimum of engineering supervision. Illustrative examples are included to facilitated explanation of the procedure by carrying out the computations on a typical gas-turbine disk through a complete running cycle."
Date: 1948
Creator: Millenson, M. B. & Manson, S. S.
Partner: UNT Libraries Government Documents Department

The Development of a Hollow Blade for Exhaust Gas Turbines

Description: The subject of the development of German hollow turbine blades for use with internal cooling is discussed in detail. The development of a suitable blade profile from cascade theory is described. Also a discussion of the temperature distribution and stresses in a turbine blade is presented. Various methods of manufacturing hollow blades and the methods by which they are mounted in the turbine rotor are presented in detail.
Date: December 1950
Creator: Kohlmann, H.
Partner: UNT Libraries Government Documents Department

Physical Data on Certain Alloys for High Temperature Applications

Description: Report presenting data constituting a summary of the physical properties of 120 samples of metal alloys, representing 86 different compositions which have been investigated for their suitability as turbosupercharger wheel materials. Some of the reported data include the chemical composition, fabrication procedure, tensile-test and hardness values at room temperature, and tensile and rupture-test characteristics at 1200 degrees Fahrenheit.
Date: April 1943
Creator: White, A. E.; Freeman, J. W. & Rote, F. B.
Partner: UNT Libraries Government Documents Department

Performance of Blowdown Turbine Driven by Exhaust Gas of Nine-Cylinder Radial Engine

Description: "An investigation was made of an exhaust-gas turbine having four separate nozzle boxes each covering a 90 degree arc of the nozzle diaphragm and each connected to a pair of adjacent cylinders of a nine-cylinder radial engine. This type of turbine has been called a "blowdown" turbine because it recovers the kinetic energy developed in the exhaust stacks during the blowdown period, that is the first part of the exhaust process when the piston of the reciprocating engine is nearly stationary. The purpose of the investigation was to determine whether the blow turbine could develop appreciable power without imposing any large loss in engine power arising from restriction of the engine exhaust by the turbine" (p. 243).
Date: 1944
Creator: Turner, L. Richard & Desmon, Leland G.
Partner: UNT Libraries Government Documents Department

Thermodynamic Data for the Computation of the Performance of Exhaust-Gas Turbines

Description: "Information published in chemical journals from 1933 to 1939 on the thermodynamic properties of the component gases of exhaust gases based on spectroscopic measurements were used as data for computing the ideal values of work, mass flow, nozzle velocity, power, and temperature change involved in the thermodynamic properties of a gas turbine. Curves from which this information can conveniently be obtained are given. An additional curve is included from which the heat flow may be calculated for nonadiabatic processes" (p. 1).
Date: October 1945
Creator: Pinkel, Benjamin & Turner, L. Richard
Partner: UNT Libraries Government Documents Department

High Temperature Characteristics of 17 Alloys at 1200 and 1350 Degrees F

Description: Report presenting the results of a study of the rupture-test characteristics of 13 wrought and 4 cast alloys which were considered to have promise for service in exhaust gas turbines. The results are given in the forms of a table of information and data, a page of curves, and a page of photomicrographs.
Date: March 1944
Creator: Freeman, J. W.; Rote, F. B. & White, A. E.
Partner: UNT Libraries Government Documents Department

The Combination of Internal-Combustion Engine and Gas Turbine

Description: "While the gas turbine by itself has been applied in particular cases for power generation and is in a state of promising development in this field, it has already met with considerable success in two cases when used as an exhaust turbine in connection with a centrifugal compressor, namely, in the supercharging of combustion engines and in the Velox process, which is of particular application for furnaces. In the present paper the most important possibilities of combining a combustion engine with a gas turbine are considered. These "combination engines " are compared with the simple gas turbine on whose state of development a brief review will first be given" (p. 1).
Date: April 1947
Creator: Zinner, K.
Partner: UNT Libraries Government Documents Department

Cooperative Research and Development for Advanced Microturbines Program on Advanced Integrated Microturbine System

Description: The Advanced Integrated Microturbine Systems (AIMS) project was kicked off in October of 2000 to develop the next generation microturbine system. The overall objective of the project was to develop a design for a 40% electrical efficiency microturbine system and demonstrate many of the enabling technologies. The project was initiated as a collaborative effort between several units of GE, Elliott Energy Systems, Turbo Genset, Oak Ridge National Lab and Kyocera. Since the inception of the project the partners have changed but the overall direction of the project has stayed consistent. The project began as a systems study to identify design options to achieve the ultimate goal of 40% electrical efficiency. Once the optimized analytical design was identified for the 40% system, it was determined that a 35% efficient machine would be capable of demonstrating many of the advanced technologies within the given budget and timeframe. The items that would not be experimentally demonstrated were fully produced ceramic parts. However, to understand the requirements of these ceramics, an effort was included in the project to experimentally evaluate candidate materials in representative conditions. The results from this effort would clearly identify the challenges and improvement required of these materials for the full design. Following the analytical effort, the project was dedicated to component development and testing. Each component and subsystem was designed with the overall system requirements in mind and each tested to the fullest extent possible prior to being integrated together. This method of component development and evaluation helps to minimize the technical risk of the project. Once all of the components were completed, they were assembled into the full system and experimentally evaluated.
Date: May 30, 2007
Creator: Bowman, Michael J.
Partner: UNT Libraries Government Documents Department