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Performance evaluation of reduced-chord rotor blading as applied to J73 two-stage turbine 4: over-all performance of first-stage turbine with reduced-chord rotor blades at inlet conditions of 35 inches of mercury absolute and 700 R

Description: Report presenting a study of the first stage performance characteristics of the two-stage turbine from the J73 turbojet engine. The reduced-chord first-stage turbine operated at a peak brake internal efficiency of over 91 percent at a stage overall pressure ratio of 1.4 and at 90 percent of the design equivalent speed. The unit exhibited high efficiency over a wide range of operating variables.
Date: July 5, 1957
Creator: Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Performance evaluation of reduced-chord rotor blading as applied to J73 two-stage turbine 5: effect of inlet pressure on over-all performance at design speed and inlet temperature of 700 degrees R

Description: Report presenting an investigation of a reduced-chord multistage turbine at design speed and various turbine-inlet pressures from 12 to 40 inches of mercury absolute. At each inlet pressure, the turbine was operated over a range of overall turbine total-pressure ratios; turbine-inlet temperature was maintained at 700 degrees R. The results indicated that no appreciable effect on turbine overall performance was observed over the range of turbine-inlet total pressures investigated.
Date: July 5, 1957
Creator: Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Component performance investigation of J71 experimental turbine 1: Over-all performance with 97-percent-design stator areas

Description: From Summary: "The over-all component performance characteristics of a J71 experimental three-stage turbine with 97 percent design stator areas were determined over a range of speed and pressure ratio at inlet-air conditions of approximately 35 inches of mercury absolute and 700 degrees R. The turbine break internal efficiency at design operating conditions was 0.877; the maximum efficiency of 0.886 occurred at a pressure ratio of 4.0 at 120 percent of design equivalent rotor speed. In general, the turbine yielded a wide range of efficient operation, permitting flexibility in the choice of different modes of engine operation."
Date: April 11, 1956
Creator: Schum, Harold J. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Performance Evaluation of Reduced-Chord Rotor Blading as Applied to J73 Two-Stage Turbine 6: Stage Performance With Standard Rotor Blading at Inlet Conditions of 35 Inches of Mercury Absolute and 700 Degrees R

Description: Report presenting an evaluation of the stage performance of the J73 turbine on the basis of previous performance investigations of the first stages alone and of the two-stage turbines with standard and with reduced-chord rotor blading for a range of rotational speeds and pressure ratios. The results demonstrated that both of the two-stage turbines and first-stage turbines had comparable performance.
Date: July 11, 1957
Creator: Davison, Elmer H. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Performance of Single-Stage Turbine of Mark 25 Torpedo Power Plant with Two Special Nozzles 1 - Efficiency with 0.45-inch Rotor Blades

Description: "An investigation was made of the first-stage turbine of a Mark 25 torpedo power plant to determine the performance of the unity with two nozzle configurations and a special rotor having 0.45-inch blades instead of the standard length of 0.40 inch. Both nozzles had smaller passages than the nozzles of similar shape that were previously investigated. The performance of the nozzle-blade combinations is evaluated in terms of brake, rotor, and blade efficiency as functions of blade-jet speed ratio for three pressure ratios" (p. 1).
Date: August 23, 1949
Creator: Schum, Harold J. & Whitney, Warren J.
Partner: UNT Libraries Government Documents Department

Performance of Single-Stage Turbine of Mark 25 Torpedo Power Plant with Two Nozzles and Three Rotor-Blade Designs

Description: From Summary: "A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzles and three rotor-blade designs. The performance was evaluated in terms of brake, rotor, and blade efficiencies at pressure ratios of 8, 15 (design), and 20. The blade efficiencies with the two nozzles are compared with those obtained with four other nozzles previously investigated with the same three rotor-blade designs."
Date: September 9, 1949
Creator: Schum, Harold J. & Whitney, Warren J.
Partner: UNT Libraries Government Documents Department

Performance evaluation of reduced-chord rotor blading as applied to J73 two-stage turbine 2: over-all performance at inlet conditions of 35 inches of mercury absolute and 700 degrees R

Description: Report presenting an investigation to determine the feasibility of utilizing a reduced-chord rotor blading on the two-stage turbine of the J73 turbojet engine in order to reduce the weight. The turbine was operated as a component over a range of speeds and overall pressure ratios at turbine-inlet conditions corresponding to 35 inches of mercury absolute and 700 degrees R. Results regarding the overall performance, performance map, and peak efficiency are provided.
Date: July 11, 1957
Creator: Schum, Harold J.; Rebeske, John J., Jr. & Forrette, Robert E.
Partner: UNT Libraries Government Documents Department

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor-tip speed 6: experimental performance of two-stage turbine

Description: The brake internal efficiency of the highly loaded two-stage turbine was 0.79 equivalent design work and speed. The maximum brake internal efficiency was 0.84. A radial survey revealed these major defects: (1) the first-rotor throat area was too large, and a large area of underturned flow existed near the tip;(2) considerable underturning existed at the second-stator outlet; and (3) tangential components of velocity at the turbine outlet amounted to 2.5 points in turbine efficiency.
Date: August 20, 1956
Creator: Davison, Elmer H.; Schum, Harold J. & Petrash, Donald A.
Partner: UNT Libraries Government Documents Department

Investigation of turbines suitable for use in a turbojet engine with high compressor ratio and low compressor-tip speed 5: experimental performance of two-stage turbine with downstream stator

Description: An experimental investigation of a highly loaded two-stage turbine with a downstream stator revealed that (1) at equivalent design work and speed the brake internal efficiency was 0.81 and the maximum efficiency obtained was 0.85, and (2) the downstream stator left very little energy in the form of tangential velocity in the gas and, in general, performed well with 0.78 recovery being obtained at equivalent design work and speed.
Date: October 21, 1951
Creator: Davison, Elmer H.; Petrash, Donald A. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor-tip speed 8: Internal flow conditions of a two-stage turbine with a downstream stator

Description: Report presenting an investigation of a two-stage turbine with a downstream stator to determine the interstage flow conditions of the turbine. Results regarding stage efficiency and work output, first-stage performance, second-stage performance, and downstream-stator performance are provided.
Date: November 13, 1957
Creator: Petrash, Donald A.; Davison, Elmer H. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Component performance investigation of J71 experimental turbine 7: effect of first-stator adjustment; over-all performance of J71 turbine with 87-percent-design stator area

Description: The performance results, as well as a compressor-turbine match point study based on a particular mode of engine operation, are compared with those previously obtained with the same turbine having first-stator areas 70, 95.6, and 132 percent of design. Maximum efficiencies for all turbine configurations were high, on the order of 87 to 89 percent. The efficiencies obtained at the match points for the 87-, 95.6-, and 132-percent turbines were slightly lower. No match point for the 70-percent turbine was obtained because, with first-stator areas less than 75.5 percent of design, the turbine would develop insufficient work to drive the compressor at the match point.
Date: January 14, 1957
Creator: Schum, Harold J.; Petrash, Donald A. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Component performance investigation of L71 experimental turbine 10: effect of first-stator adjustment; internal flow conditions of J71-97 turbine with 132-percent-design stator area

Description: Report presenting an investigation of the changes in the internal flow conditions resulting from adjusting the first-stator throat area of the J71 experimental three-stage turbine. The results of interstage flow measurements obtained from a radial survey investigation conducted on the turbine when equipped with a first-stage stator with the throat area increased to 132 percent of the design area and operated at a single predetermined turbine match point are also provided.
Date: January 16, 1958
Creator: Petrash, Donald A.; Schum, Harold J. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Component performance investigation of J71 experimental turbine 8: effect of first-stator adjustment; internal flow conditions of J71-97 turbine with 70-percent-design stator area

Description: Results of a survey investigation of the J71-97 experimental three-stage turbine equipped with a first-stator area 70 percent pf design are presented and compared with the turbine with a first-stator area 97 percent of design.
Date: January 18, 1957
Creator: Petrash, Donald A.; Schum, Harold J. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Component performance investigation of J71 experimental turbine 6: effect of first-stator adjustment; over-all performance of J71-97 turbine with 70-percent-design stator area

Description: Report presenting an investigation of the effect of first-stator area changes on the overall component performance of the J71-97 experimental turbine. The performance of the turbine with the first-stator area reduced to 70 percent of design by reorienting the stagger angle of the design blade profiles is presented. Results regarding the overall performance, choking characteristics, and matching characteristics are provided.
Date: October 2, 1956
Creator: Schum, Harold J.; Petrash, Donald A. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Investigation of centrifugal compressor operated as a centripetal refrigeration turbine

Description: Report presenting testing of a centrifugal compressor from a production-type turbojet engine, which was successfully operated as a centripetal refrigeration turbine over a range of rotor speed, inlet pressure, and pressure ratio for full admission. The performance results indicated that partial admission was found to be the most efficient method of turbine control, but throttling at the turbine inlet was easy to apply. When nozzles are used, they should have erosion-resistant surfaces to minimize erosion effects.
Date: December 4, 1950
Creator: Rebeske, John J., Jr.; Parisen, Richard B. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Performance of Single-Stage Turbine of Mark 25 Torpedo Power Plant with Two Special Nozzles 2 - Efficiency with 20 Degrees-Inlet-Angle Rotor Blades

Description: "A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzle designs in combination with special rotor blades having a 20 inlet angle. The performance is presented in terms of blade, rotor, and brake efficiency as a function of blade-jet speed ratio for pressure ratios of 8, 15 (design), and 20. The blade efficiency with the nozzle having circular pas- sages (K) was equal to or higher than that with the nozzle having rectangular passages (J) for all pressure ratios and speeds investigated" (p. 1).
Date: August 25, 1949
Creator: Schum, Harold J. & Whitney, Warren J.
Partner: UNT Libraries Government Documents Department

Investigation of X24C-2 10-Stage Axial-Flow Compressor 2: Effect of Inlet-Air Pressure and Temperature of Performance

Description: Effect of inlet-air pressure and temperature on the performance of the X24-2 10-Stage Axial-Flow Compressor from the X24C-2 turbojet engine was evaluated. Speeds of 80, 89, and 100 percent of equivalent design speed with inlet-air pressures of 6 and 12 inches of mercury absolute and inlet-air temperaures of approximately 538 degrees, 459 degrees,and 419 degrees R ( 79 degrees, 0 degrees, and minus 40 degrees F). Results were compared with prior investigations.
Date: August 21, 1947
Creator: Finger, Harold B.; Schum, Harold J. & Buckner, Howard A., Jr.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Experimental Turbine 4 - Effect of First-Stator Adjustment; Over-All Performance of J71-97 Turbine With 132-Percent-Design Stator Area

Description: An experimental invesitgation of the effect of increasing the first-stator area of the J71-97 experimental three-stage turbine from 97 percent of design to 132 percent revealed (1) the maximum efficiency obtained decreased from 0.891 to 0.869, (2) the choking equivalent weight flows increased by approximately 13.6 percent, and (3) at the turbine match points required to maintain the compressor at constant design equivalent conditions the turbine efficiency decreased from 0.87 to 0.86.
Date: April 17, 1956
Creator: Davison, Elmer H.; Petrash, Donald A. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Experimental Turbine 9 - Effect of First-Stator Adjustment;Internal Flow Conditions of J71-97 Turbine With 87-Percent-Design Stator Area

Description: "An experimental radial-survey investigation of the J71-97 three-stage turbine equipped with a first stator having a throat area 87 percent of the design value was conducted at one turbine operating point. The first-, second-, and third-stage mass-averaged efficiencies were 0.897, 0.843, and 0.755, respectively. The corresponding over-all turbine efficiency was 0.856" (p. 1).
Date: April 30, 1957
Creator: Schum, Harold J.; Petrash, Donald A. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Experimental Turbine 3 - Effect of Third-Stage Shrouding on Over-All Performance

Description: "A negligible effect on turbine efficiency and only a small decrease in turbine weight flow were observed when the J71 experimental turbine with 97-percent-design stator areas was modified to include shrouding of the third-stage rotor" (p. 1).
Date: April 17, 1956
Creator: Petrash, Donald A.; Schum, Harold J. & Davison, Elmer H.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Type II Turbines 5 - Internal Flow Conditions of J71 Type IIA Turbine

Description: An experimental investigation of the J71 Type IIA turbine was conducted at the equivalent design speed and work output. The design stagework distribution was closely approached, although the design vector diagram was not attained. Efficiencies of 0.904, 0.851, and 0.806 were obtained for the first, second, and third stages, respectively. Losses occurred near the hub and tip for all three rotors. The third-stage losses, however, were significantly greater than those of either the first or second stage.
Date: 1955
Creator: Schum, Harold J.; Davison, Elmer H. & Petrash, Donald A.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Type II Turbines 3 - Overall Performance of J71 Type IIA Turbine

Description: "The over-all component performance characteristics of the J71 Type IIA three-stage turbine were experimentally determined over a range of speed and over-all turbine total-pressure ratio at inlet-air conditions af 35 inches of mercury absolute and 700 deg. R. The results are compared with those obtained for the J71 Type IIF turbine, which was previously investigated, the two turbines being designed for the same engine application. Geometrically the two turbines were much alike, having the same variation of annular flow area and the same number of blades for corresponding stator and rotor rows" (p. 1).
Date: January 20, 1955
Creator: Schum, Harold J.; Davison, Elmer H. & Petrash, Donald A.
Partner: UNT Libraries Government Documents Department

Investigation of Turbines for Driving Supersonic Compressors 2: Performance of First Configuration With 2.2 Percent Reduction in Nozzle Flow Area

Description: "The experimental performance of a modified turbine for driving a supersonic compressor is presented and compared with the performance of the original configuration to illustrate the effect of small changes in the ratio of nozzle-throat area to rotor-throat area. Performance is based on the performance of turbines designed to operate with both blade rows close to choking. On the basis of the results of this investigation, the ratio of areas is concluded to become especially critical in the design of turbines such as those designed to drive high-speed, high-specific weight-flow compressors where the turbine nozzles and rotor are both very close to choking" (p. 1).
Date: July 22, 1952
Creator: Stewart, Warner L.; Schum, Harold J. & Wong, Robert Y.
Partner: UNT Libraries Government Documents Department

Investigation of Turbines for Driving Supersonic Compressors: 1: Design and Performance of First Configuration

Description: Report presenting the design and performance of a turbine to drive a supersonic compressor in order to determine the problems that would be encountered in turbines required to drive high-speed, high-weight-flow compressors. A model of the turbine was built and operated over a range of speed and total-pressure ratios. Results regarding performance, the effects of rotor choking, and possible modifications to the design are provided.
Date: June 17, 1952
Creator: Stewart, Warner L.; Schum, Harold J. & Whitney, Warren J.
Partner: UNT Libraries Government Documents Department