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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

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. Over the range of speeds and pressure ratios investigated, the efficiency with the nozzle having rectangular passages (J) was higher than that with a nozzle having circular passages (K). The difference in blade efficiencies varied from less than 0.010 at the lower blade-jet speed ratios for the three pressure ratios investigated to 0.030 at a pressure ratio of 8 and a blade-jet speed ratio of 0.295. The efficiencies with these tow nozzles were generally lower than those obtained with nozzles previously reported in combination with the 0.45-inch blades.
Date: May 4, 1949
Creator: Schum, Harold J. & Whitney, Waren J.
Partner: UNT Libraries Government Documents Department

Performance evaluation of reduced-chord rotor blading as applied to J23 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: Davidson, Elmer H. & 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

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

Investigation of turbines for driving supersonic compressors: II: 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.
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 4:design and performance of second configuration including study of three-dimensional flow effects

Description: Report presenting the design and experimental performance of a turbine configuration designed to drive a high-speed, high specific-weight-flow supersonic compressor. Results regarding two configurations and their work output, design weight flow, and blade loading are provided.
Date: May 18, 1953
Creator: Whitney, Warren J.; Stewart, Warner L. & Schum, Harold 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

Component performance investigation of J71 experimental turbine IX: effect of first-stator adjustment;internal flow conditions of J71-97 turbine with 87-percent-design stator area

Description: From Summary: "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."
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: IV - 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

Effect of First-Stage Blade Design on Performance of Mark 25 Torpedo Power Plant

Description: The effect of rotor-blade length, inlet angle, and shrouding was investigated with four different nozzles in a single-stage modification of the Mark 25 aerial-torpedo power plant. The results obtained with the five special rotor configurations are compared with those of the standard first-stage rotor with each nozzle. Each nozzle-rotor combination was operated at nominal pressure ratios of 8, 15 (design), and 20 over a range of speeds from 6000 rpm to the design speed of 18,000 rpm. Inlet temperature and pressure conditions of 1OOOo F and 95 pounds per square inch gage, respectively, were maintained constant for all runs.
Date: August 4, 1948
Creator: Schum, Harold J. & Hoyt, Jack W.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Experimental Turbine: III - 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.
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 V - 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

Performance of Single-Stage Turbine of Mark 25 Torpedo Power Plant with Two Special Nozzles, II, 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. The maximum blade efficiency of 0.571 was obtained with nozzle K at a pressure ratio of 8 and a blade-jet speed ratio of 0.296. The difference in blade efficiency was negligible at a pressure ratio of 8 at the low speeds; the maxim difference was 0.040 at a pressure ratio of 20 and a blade-jet speed ratio of 0.260.
Date: August 25, 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 Special Nozzles, III, Efficiency with Standard Rotor Blades

Description: A Mark 25 torpedo power plant modified to operate as a single-stage turbine was investigated to determine the performance with two nozzle designs and a standard first-stage rotor having 0.40-inch blades with a 17O met-air angle. Both nozzles had smaller port cross-sectional areas than those nozzles of similar design, which were previously investigated. The performance of the two nozzles was compared on the basis of blade, rotor, and brake efficiencies as a function of blade-jet speed ratio for pressure ratios of 8, 15 (design), and 20. At pressure ratios of 15 and 20, the blade efficiency obtained with the nozzle having circular passages (K) was higher than that obtained with the nozzle having rectangular passages (J). At a pressure ratio of 8, the efficiencies obtained with the two nozzles were comparable for blade-jet speed ratios of less than 0.260. For blade-jet speed ratios exceeding this value, nozzle K yielded slightly higher efficiencies. The maximum blade efficiency of 0.569 was obtained with nozzle K at a pressure ratio of 8 and a blade-jet speed ratio of 0.295. At design speed and pressure ratio, nozzle K yielded a maximum blade efficiency of 0.534, an increase of 0.031 over that obtained with nozzle J. When the blade efficiencies of the two nozzles were compared with those of four other nozzles previously investigated, the maximum difference for the six nozzles with this rotor was 0.050. From, this comparison, no specific effect of nozzles size or shape on over-all performance was discernible.
Date: January 1, 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 Jr.
Partner: UNT Libraries Government Documents Department

Investigation of 10-stage axial-flow X24C-2 compressor, 1, performance at inlet pressure of 21 inches mercury absolute and inlet temperature of 538 degrees R

Description: The performance at inlet pressure of 21 inches mercury absolute and inlet temperature of 538 R for the 10-stage axial-flow X24C-2 compressor from the X24C-2 turbojet engine was investigated. the peak adiabatic temperature-rise efficiency for a given speed generally occurred at values of pressure coefficient fairly close to 0.35.For this compressor, the efficiency data at various speeds could be correlated on two converging curves by the use of a polytropic loss factor derived.
Date: July 15, 1947
Creator: Schum, Harold J. & Buckner, Howard A., Jr.
Partner: UNT Libraries Government Documents Department

Component Performance Investigation of J71 Type II Turbines: III - 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. However, the blade throat areas downstream of the first stator of the IIA turbine were smaller than those of the IIF; and the IIA blade profiles were curve-backed, whereas those of the IIF were straight-backed. The IIA turbine passed the equivalent design weight flow and had a brake internal efficiency of 0.880 at design equivalent speed and work output. A maximum efficiency of 0.896 occurred at 130 percent of design equivalent speed and a pressure ratio of 4.0. The turbine had a wide range of efficient operation. The IIA turbine had slightly higher efficiencies than the IIF turbine at comparable operating conditions. The fact that the IIA turbine obtained the design equivalent weight flow at the design equivalent operating point was probably a result of the decrease in the blading throat areas downstream of the first stator from those of the IIF turbine, which passed 105 percent of design weight flow at the corresponding operating point. The third stator row of blades of the IIA turbine choked at the design equivalent speed and at an over-all pressure ratio of 4.2; the third rotor choked at a pressure ratio of approximately 4.9.
Date: January 20, 1955
Creator: Schum, Harold J.; Davison, Elmer H. & Petrash, Donald A.
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