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Investigation of Two-Stage Counterrotating Compressor. 3: Design of Second-Stage Rotor and Preliminary Over-All Performance

Description: At the design speed of a two-stage counterrotating compressor, an overall average pressure ratio of 4.3 was obtained at a specific weight flow of 27.2 pounds per second per square foot frontal area with an adiabatic efficiency of 0.75. Preliminary tests indicate that a weight-flow mismatching exists between the two rotors that causes the first rotor to operate at less than peak efficiency at design speed. At lower speeds, the first stage was forced to operate in the stalled region in single-stage tests. With the second rotor installed, no periodic rotating stall was observed, although random fluctations of similiar magnitude were noted.
Date: October 22, 1956
Creator: Wilcox, Ward W. & Wright, Linwood C.
Partner: UNT Libraries Government Documents Department

A Device for Measuring Sonic Velocity and Compressor Mach Number

Description: "A device has been developed which measures the velocity of sound in fluids at stagnation and is especially adaptable to turbine and compressor testing for which the constituency of the working fluid may be in doubt. By utilizing the shaft frequency of a rotary compressor, the instrument can also be used to provide a direct measurement of the compressor Mach number (ratio of blade-tip velocity to inlet velocity of sound at stagnation). A Helmholtz resonator is employed in the measurement of the sound velocity" (p. 1).
Date: January 16, 1947
Creator: Huber, Paul W. & Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department

An analytical investigation using aerodynamic limitations of several designs of high stage pressure ratio multistage compressors

Description: From Introduction: "As more quantitative information becomes available, more will be known of the maximum stage total-pressure ratios that can be used while maintaining acceptable efficiences and weight flows. Because quantitative knowledge is limited, the qualitative nature of limiting factors and trends are investigated herein."
Date: December 1951
Creator: Voit, Charles H. & Thomson, Arthur R.
Partner: UNT Libraries Government Documents Department

Analysis of part-speed operation for high-pressure-ratio multistage axial-flow compressors

Description: From Introduction: "For the analysis reported herein, the same hypothetical 12-stage compressor discussed in reference 6 was chosen, and the effects of inlet-stage stall characteristics and stage interactions were estimated by arbitrary adjustment of the stall characteristics and stage interactions were estimated by arbitrary adjustment of the stalled characteristics of the individual stages."
Date: December 4, 1953
Creator: Benser, William A.
Partner: UNT Libraries Government Documents Department

Analysis of transonic rotor-blade passage loss with hot-wire anemometers

Description: From Introduction: "This report presents data from measurements of the flow in a single-stage research compressor, which supports the model of reference 1. A calculated shock technique similar to that of reference 1 is incorporated with these experimental results. Another approach for estimating passage shock loss given a flow rate and blade geometry was reported in reference 2."
Date: June 5, 1958
Creator: Lewis, George W.; Tysl, Edward R. & Fessler, Theodore E.
Partner: UNT Libraries Government Documents Department

Analysis of Stage Matching and Off-Design Performance of Multistage Axial-Flow Compressors

Description: From Introduction: "The present report is intended to give a qualitative picture of the operation of each stage of a multistage compressor over a range of actual operating conditions from 50 to 100 percent design speed and to point out some means of achieving improved off-design performance. The method used in the report is primarily analytical and is based on single-stage-performance results."
Date: June 27, 1952
Creator: Finger, Harold B. & Dugan, James F., Jr.
Partner: UNT Libraries Government Documents Department

Preliminary analysis of over-all performance of an eight-stage axial -flow research compressor with two long-chord transonic inlet stages

Description: Report presenting a study of the performance of a modified compressor over a range of weight flows at a constant Reynolds number. The chords of the first two stages of the eight-stage axial-flow compressor had two transonic inlet stages doubled. Results regarding the long-chord-compressor performance and a comparison of long-chord and medium-chord compressors are provided.
Date: February 10, 1958
Creator: Sievers, Gilbert K.; Geye, Richard P. & Lucas, James G.
Partner: UNT Libraries Government Documents Department

Standard Procedures for Rating and Testing Multistage Axial-Flow Compressors

Description: "In order to establish a standard procedure for rating and testing multistage axial-flow compressors, the NACA Subcomittee on Compressors appointed a panel to write such a procedure. This panel made recommendations for standardization of test setups, instrumentation, test procedure, data to be taken, and the presentation of the data. These recommendations are presented" (p. 1).
Date: September 1946
Creator: NACA Subcommittee on Compressors
Partner: UNT Libraries Government Documents Department

Effect of Inlet Air Distortion on the Steady-State and Surge Characteristics of an Axial-Flow Turbojet Compressor

Description: "An investigation was conducted in an altitude test chamber to determine the effects of inlet airflow distortion on the compressor steady-state and surge characteristics of a high-pressure ratio, axial-flow turbojet engine. Circumferential-type inlet flow distortions were investigated, which covered a range of distortion sector angles from 20 deg to 168 deg and distortion levels up to 22 percent. The presence of inlet airflow distortions at the compressor face resulted in a substantial increase in the local pressure ratio in the distorted region, primarily for the inlet stages" (p. 1).
Date: January 2, 1948
Creator: Ciepluch, Carl C.
Partner: UNT Libraries Government Documents Department

Investigation of Reynolds number effect on performance of an eight-stage axial-flow research compressor with long- and medium-chord lengths in the two transonic inlet stages

Description: Report presenting an investigation of the Reynolds number effects on an axial-flow compressor with two of the transonic inlet stages doubled as compared to the original compressor. Results regarding the long-chord-compressor performance, effect of Reynolds number on compressor performance, and a comparison of long- and medium-chord compressor performance are provided.
Date: February 18, 1958
Creator: Sievers, Gilbert K.; Geye, Richard P. & Lucas, James G.
Partner: UNT Libraries Government Documents Department

Design and performance of experimental axial-discharge mixed-flow compressor 2: performance of impeller

Description: Report presenting an analysis of an axial-discharge mixed-flow compressor designed to combine the compactness, reliability, and wide operating range of a mixed-flow compressor with the high flow capacity per unit of frontal area that characterizes the axial-flow compressor. The primary objective of this design was to maximize the flow capacity for a predetermined pressure ratio. Results regarding the flow distribution at the impeller inlet, flow distribution at the impeller outlet, and impeller performance are provided.
Date: August 12, 1948
Creator: Wilcox, Ward W.
Partner: UNT Libraries Government Documents Department

Reynolds number effect on axial-flow compressor performance

Description: Investigation conducted in the altitude wind tunnel to study the effect of Reynolds number on the performance of an axial-flow compressor. The compressor was operated as a part of a turbojet engine over a range of pressure altitudes and compressor-inlet Reynolds numbers. Results regarding compressor efficiency, air flow, and a comparison with axial-flow compressors of different design are provided.
Date: September 15, 1949
Creator: Wallner, Lewis E. & Fleming, William A.
Partner: UNT Libraries Government Documents Department

Aerodynamic design of axial-flow compressors: Volume 3

Description: Chapters XI to XIII concern the unsteady compressor operation arising when compressor blade elements stall. The fields of compressor stall and surge are reviewed in Chapters XI and XII, respectively. The part-speed operating problem in high-pressure-ratio multistage axial-flow compressors is analyzed in Chapter XIII. Chapter XIV summarizes design methods and theories that extend beyond the simplified two-dimensional approach used previously in the report. Chapter XV extends this three-dimensional treatment by summarizing the literature on secondary flows and boundary layer effects. Charts for determining the effects of errors in design parameters and experimental measurements on compressor performance are given in Chapters XVI. Chapter XVII reviews existing literature on compressor and turbine matching techniques.
Date: August 1, 1956
Creator: Johnsen, Irving A.; Bullock, Robert O.; Graham, Robert W.; Costilow, Eleanor L.; Huppert, Merle C.; Benser, William A. et al.
Partner: UNT Libraries Government Documents Department

Investigation of a supersonic-compressor rotor with turning to axial direction 1: rotor design and performance

Description: Report presenting an approximate, quasi-three-dimensional design procedure adapted to the design of high solidity, impulse-type supersonic compressors. The method is applied to a compressor rotor with a tip speed of 1600 feet per second in air, an inlet hub-tip radius ratio of 0.75, and an axial discharge relative to the rotor. Results regarding the overall performance, rotor-entrance conditions, static-pressure profiles, discharge conditions, and discharge surveys are provided.
Date: August 19, 1953
Creator: Tysl, Edward R.; Klapproth, John F. & Hartmann, Melvin J.
Partner: UNT Libraries Government Documents Department

Investigation of a 10-stage subsonic axial-flow research compressor 3: investigation of rotating stall, blade vibration and surge at low and intermediate compressor speeds

Description: Report presenting an investigation of rotating stall and surge at low and intermediate speeds conducted on a 10-stage subsonic axial-flow research compressor. Fluctuations of rotating stall and surge were detected by hot-wire anemometers and pressure transducers. Results regarding overall performance and rotating stall, rotating stall and blade vibration, surge, and discussion of surge are provided.
Date: May 18, 1953
Creator: Huppert, Merle C.; Costilow, Eleanor L. & Budinger, Ray E.
Partner: UNT Libraries Government Documents Department

Investigation of off-design performance of shock-in-rotor type supersonic blading

Description: An analysis of the off-design performance of shock-in rotor-type supersonic blading is presented. The over-all losses are assumed divided into two groups;normal-shock losses, and external-wave losses. Throughout the range of relative entrance Mach numbers from 1.35 to starting, the largest losses can be attributed to the normal shock. An improvement in performance would be expected with a reduction of the normal-shock losses by the introduction of external compression waves.
Date: May 7, 1951
Creator: Graham, Robert C.; Klapproth, John F. & Barina, Frank J.
Partner: UNT Libraries Government Documents Department

Altitude-Wind-Tunnel Investigation of a 4000-Pound-Thrust Axial-Flow Turbojet Engine. 2 - Operational Characteristics

Description: From Summary: "An investigation was conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of an axial flow-type turbojet engine with a 4000-pound-thrust rating over a range of pressure altitudes from 5,000 to 50,000 feet, ram pressure ratios from 1.00 to 1.86, and temperatures from 60 deg to -50 deg F. The low-flow (standard) compressor with which the engine was originally equipped was replaced by a high-flow compressor for part of the investigation. The effects of altitude and airspeed on such operating characteristics as operating range, stability of combustion, acceleration, starting, operation of fuel-control systems, and bearing cooling were investigated."
Date: August 6, 1948
Creator: Fleming, William A.
Partner: UNT Libraries Government Documents Department

Altitude-Wind-Tunnel Investigation of a 3000-Pound-Thrust Axial-Flow Turbojet Engine 2 - Analysis of Compressor Performance

Description: Compressor performance properties for two 11-stage compressors of 3000-pound-thrust axial-flow turbojet engines were determined. Data are presented for a range of simulated altitudes and a range of Mach numbers for various modifications of the engine.
Date: August 23, 1948
Creator: Dietz, Robert O., Jr.; Berdysz, Joseph J. & Howard, Ephraim M.
Partner: UNT Libraries Government Documents Department

Design and Performance of Family of Diffusing Scrolls with Mixed-flow Impeller and Vaneless Diffuser

Description: Report presenting a study of a family of diffusing scrolls designed for use with a mixed-flow impeller and a small-diameter vaneless diffuser. Results regarding a comparison of performance of scrolls and comparison of performance of various compressor configurations are provided.
Date: May 1948
Creator: Brown, W. Byron & Bradshaw, Guy R.
Partner: UNT Libraries Government Documents Department

Experimental investigation of effects of design changes on performance of large-capacity centrifugal compressors

Description: Report presenting an investigation to determine the effects of several design changes on the performance of large-capacity, double-entry, centrifugal compressors. Four modifications of a turbojet engine compressor were operated over a range of equivalent impeller tip speeds an the compressor overall and component performances were determined. Results regarding the impeller performance, diffuser performance, and compressor performance are provided.
Date: March 2, 1951
Creator: Withee, Joseph R., Jr.; Kovach, Karl & Ginsburg, Ambrose
Partner: UNT Libraries Government Documents Department

Investigation of an Experimental Supersonic Axial-Flow Compressor

Description: An investigation is in progress at the Langley Laboratory of the NACA to explore the possibilities of axial-flow compressors operating with supersonic velocities relative to the blade rows. The first phase of this investigation, a study of supersonic diffusers, has been reported. The second phase, an analysis of supersonic compressors, has also been reported. Preliminary calculations have shown that very high pressure ratios across a stage, together with somewhat increased mass flows, are possible with compressors which decelerate air through the speed of sound in their rotor blading. These performance characteristics are desirable in compressors for aircraft jet propulsion units, gas turbines, or superchargers. The third phase, presented here, is a preliminary experimental investigation of a supersonic compressor designed to produce a high pressure ratio in a single stage.
Date: August 7, 1947
Creator: Erwin, John R.; Wright, Linwood C. & Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department

Calibration of Air-Flow Meters for J33 Compressor Investigation

Description: Flow-metering devices used by the NACA and by the manufacturer of the J33 turbojet engine were calibrated together to determine whether an observed discrepancy in weight flow of approximately 4 percent for the two separate investigations might be due to the different devices used to meter air flow. A commercial adjustable orifice and a square-edge flat-plate orifice used by the NACA and a flow nozzle used by the manufacturer were calibrated against surveys across the throat of the nozzle. It was determined that over a range of weight flows from 18 to 45 pounds per second the average weight flows measured by the metering device used for the compressor test would be 0.70 percent lower than those measured by the metering device used in the engine tests and the probable variation about this mean would be +/- 0.39 percent. The very close agreement of the metering devices shows that the greater part of the discrepancy in weight flow is attributable to the effect of inlet pressure.
Date: August 16, 1948
Creator: Kovach, Karl & Withee, Joseph R., Jr.
Partner: UNT Libraries Government Documents Department