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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 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

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

Performance of a turbojet engine with adjustable first-stage turbine stator and variable-area exhaust nozzle

Description: The performance of a turbojet engine with a two-stage turbine, an adjustable first-stage turbine stator, and a variable-area exhaust nozzle was investigated at selected constant engine speeds and two simulated flight conditions. For the particular component characteristics of the engine investigated, little improvement in thrust levels of interest by use of an adjustable rather than an optimum fixed first-stage turbine stator.
Date: August 14, 1953
Creator: Meyer, Carl L.; Smith, Ivan D. & Bloomer, Harry E.
Partner: UNT Libraries Government Documents Department

Thermodynamic study of a Roots compressor as a source of high-temperature air

Description: Report presenting an analysis to ascertain the feasibility of using the device to produce high-temperature air. The production of high temperature is associated with the leakage of the hot outlet air through the tip clearance to the inlet and the subsequent mixing with the supply air. The calculated performance of the unit is very sensitive to the assumed value of Stanton number.
Date: June 1957
Creator: Cohen, Clarence B.; Woollett, Richard R. & Weston, Kenneth C.
Partner: UNT Libraries Government Documents Department

Preliminary analysis of axial-flow compressors having supersonic velocity at the entrance of the stator

Description: Report presenting a supersonic compressor design with supersonic velocity at the entrance of the stator on the assumption of two-dimensional flow. The rotor and stator losses assumed in the analysis are based on the results of preliminary supersonic cascade tests. The starting conditions and stability of the flow in rotor and stator are discussed, and the desirability of the variable-geometry stators and adjustable guide vanes is indicated.
Date: September 12, 1949
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

Stall and flame-out resulting from firing of armament

Description: Report presenting an analysis of the causes of compressor stall and flame-out when armament is fired during flight at high altitudes. Experimental data are also presented. The increase in compressor-inlet temperature during armament firing was found to be the most important single factor affecting engine performance.
Date: August 5, 1955
Creator: Childs, J. Howard; Kochendorfer, Fred D.; Lubick, Robert J. & Friedman, Robert
Partner: UNT Libraries Government Documents Department

Aerodynamic Heat-Power Engine Operating on a Closed Cycle

Description: "Hot-air engines with dynamic compressors and turbines offer new prospects of success through utilization of units of high efficiencies and through the employment of modern materials of great strength at high temperature. Particular consideration is given to an aerodynamic prime mover operating on a closed circuit and heated externally. Increase of the pressure level of the circulating air permits a great increase of limit load of the unit. This also affords a possibility of regulation for which the internal efficiency of the unit changes but slightly. The effect of pressure and temperature losses is investigated" (p. 1).
Date: November 1942
Creator: Ackeret, J. & Keller, D. C.
Partner: UNT Libraries Government Documents Department

Flight Performance of a Jet Power Plant, 3, operating characteristics of a jet power plant as a function of altitude

Description: The performance of a jet power plant consisting of a compressor and a turbine is determined by the characteristic curves of these component parts and is controllable by the characteristics of the compressor and the turbine in relation to each other. The normal. output, overload, and throttled load of the Jet power plant are obtained on the basis of assumed straight-line characteristics.
Date: May 1951
Creator: Weinig, F.
Partner: UNT Libraries Government Documents Department

Investigation of impulse-type supersonic compressor with hub-tip ratio of 0.6 and turning to axial direction 2: stage performance with three different sets of stators

Description: Report presenting an impulse-type supersonic compressor designed for turning to the axial direction that was tested in air with three different sets of stator blades at eight angle settings.
Date: August 16, 1955
Creator: Wilcox, Ward W.
Partner: UNT Libraries Government Documents Department

Approximate design method for high-solidity blade elements in compressors and turbines

Description: Note presenting an approximate blade-element design method for compressible or incompressible nonviscous flow in high-solidity stators or rotors of axial-, radial-, or mixed-flow compressors, turbines, or two-dimensional cascades. The method is based upon channel-type flow between blade elements on a specified surface of revolution that lies between the hub and shroud and is concentric with the axis of the compressor turbine.
Date: July 1951
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department

One-dimensional compressible flow in vaneless diffusers of radial- and mixed-flow centrifugal compressors, including effects of friction, heat transfer and area change

Description: Report presenting an analysis method and a design method for one-dimensional, compressible flow with friction, heat transfer, and area change in vaneless diffusers with arbitrary profiles in the axial-radial plane. The effects of mixing losses due to nonuniform flow conditions at the impeller discharge are not considered.
Date: January 1952
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department

Two-dimensional compressible flow in centrifugal compressors with straight blades

Description: "Six numerical examples are presented for steady, two-dimensional, compressible, nonviscous flow in centrifugal compressors with thin straight blades, the center lines of which generate the surface of a right circular cone when rotated about the axis of the compressor. A seventh example is presented for incompressible flow. The solutions were obtained in a region of the compressors, including the impeller tip, that was considered to be unaffected by the diffuser vanes or by the impeller-inlet configuration" (p. 141).
Date: June 21, 1949
Creator: Stanitz, John D. & Ellis, Gaylord O.
Partner: UNT Libraries Government Documents Department

Two-dimensional cascade investigation at Mach numbers up to 1.0 of NACA 65-series blade sections at conditions typical of compressor tips

Description: Report presenting a two-dimensional high-speed cascade investigation of thin low-cambered NACA 65-series blade shapes at operating conditions typical of compressor tip sections. Testing occurred with porous walls and solid walls. Results regarding the variation of turning angle with Mach number, variation of turning angle with angle of attack, momentum loss, and schileren photographs are provided.
Date: March 17, 1958
Creator: Dunavant, James C. & Emery, James C.
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 2: velocity-diagram study of turbine for engine operation with constant exhaust-nozzle area

Description: Report presenting an investigation of whether or not a two-stage turbine with the frontal area no larger than the compressor frontal area could be satisfactorily designed to drive a particular compressor under take-off conditions. The low blade-tip speed, high work, and high air flow per unit of frontal area of the compressor make it critical that a two-stage turbine is designed to drive it. Results regarding the effect of work division, effect of variation in cone angle, and effects of radial variations on velocity diagrams are provided.
Date: June 19, 1952
Creator: Davison, Elmer H. & English, Robert E.
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