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Kofskey, M. G.

Publications and source records attributed to Kofskey, M. G..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Cold-air performance of a 12.766-centimeter-tip-diameter axial-flow cooled turbine. 1: Design and performance of a solid blade configuration

A solid blade version of a single-stage, axial-flow turbine was investigated to determine its performance over a range of speeds from 0 to 105 percent of equivalent design speed and over a range of total to static pressure ratios from 1.62 to 5.07. The results of this investigation will be used as a baseline for comparison with those obtained from a cooled version of this turbine.

Haas, J. E.↗
NASA NTRS1974

Turbine for a low cost turbojet engine. 1: Design and cold-air performance

A 24.70-cm(9.72-in.) tip diameter single-stage, axial-flow turbine was designed for a turbojet engine. Cold-air tests were made over a range of speeds from 30 to 105 percent of design equivalent speed and over a range of total-pressure ratios from 1.30 to 2.66. Results are presented in terms of specific work, torque, mass flow, and efficiency.

Kofskey, M. G.↗
NASA NTRS1974

Turbine for ordnance turbojet engine. 2: Cold-air performance with opened stator

A single-stage axial-flow turbine was investigated to determine the effect of increased stator throat area on the performance level of a turbojet engine turbine. The stator blades were bent to increase the throat area in order to move the compressor operating point in the engine farther away from surge. Results are compared with those obtained with the as-cast stator setting.

Kofskey, M. G.↗
NASA NTRS1973

Effect of reducing rotor blade inlet diameter on the performance of a 11.66-Centimeter radial-inflow turbine

The effect of increased rotor blade loading on turbine performance was investigated by reducing rotor blade inlet diameter. The reduction was made in four stages. Each modification was tested with the same stator using cold air as the working fluid. Results are presented in terms of equivalent mass flow and efficiency at equivalent design rotative speed and over a range of pressure ratios. Internal flow characteristics are shown in terms of stator exit static pressure and the radial variation of local loss and rotor-exit flow angle with radius ratio. Included are velocity diagrams calculated from the experimental results.

Kofskey, M. G.↗
NASA NTRS1973

Effect of a reduction in blade thickness on performance of a single stage 20.32 centimeter mean diameter turbine

As part of a program to reduce the manufacturing costs of a small gas-turbine engine, the turbine blading was reduced in thickness to facilitate coining. Tests were made to determine the effect of this modification on turbine performance. The working fluid was air at nominal inlet total conditions of 535 deg F and 20.0 psia. Performance results are presented and compared for four stator-rotor combinations in terms of equivalent torque, mass flow, and efficiency at equivalent design speed and at inlet-total to exit-static pressure ratios of 1.8 to 3.8

Nusbaum, W. J.↗
NASA NTRS1972

Design and cold-air investigation of a turbine for a small low-cost turbofan engine

An 8.00-in mean diameter two-stage turbine was investigated over a range of speeds from 0 to 110 percent of equivalent design speed and over a range of pressure ratios from 1.79 to 5.14. Presented are design information and turbine performance for first-stage and two-stage operation. Results are presented in terms of equivalent specific work, torque, mass flow, rotor exit flow angle, and efficiency.

Kofskey, M. G.↗
NASA NTRS1972

Recent radial turbine research at the NASA Lewis Research Center.

The major results obtained in several recent experimental programs on small radial inflow turbines for space applications are presented and discussed. Specifically, experimental and analytical work associated with these systems that has included examination of blade-shroud clearance, blade loading, and exit diffuser design, is considered. Results indicate high efficiency over a wide range of specific speed, and also insensitivity to clearance and blade loading in the radial part of the rotor. The exit diffuser investigation indicated that a conventional conical outer wall may not provide the velocity variation consistent with minimum overall diffuser loss.

Rohlik, H. E.↗
NASA NTRS1972

Aerodynamic study of a turbine designed for a small low-cost turbofan engine

An eight inch mean diameter two-stage turbine was experimentally investigated over a range of speeds from 0 to 110 percent of equivalent design speed and over a range of pressure ratios from 2.2 to 4.2. The principal results indicated that the performance level was substantially higher than that assumed in the design. As part of the program to reduce manufacturing costs, the first stage blading was reduced in thickness for ease in coining. Tests of the modified blades indicated that the aerodynamic performance of a stator or rotor blade with a large amount of reaction was effected very little by a significant change of the pressure surface.

Kofskey, M. G.↗
NASA NTRS1971

Recent radial turbine research at the NASA Lewis Research Center

The high efficiencies of small radial turbines led to their application in space power systems and numerous APU and shaft power engines. Experimental and analytical work associated with these systems included examination of blade-shroud clearance, blade loading, and exit diffuser design. Results indicate high efficiency over a wide range of specific speed and also insensitivity to clearance and blade loading in the radial part of the rotor. The exit diffuser investigation indicated that a conventional conical outer wall may not provide the velocity variation consistent with minimum overall diffuser loss.

Rohlik, H. E.↗