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High-altitude performance of an experimental turbojet combustor having variable primary-air admission

Description: Report presenting an investigation of 47 experimental tubular designs embodying variable primary-air openings to control the fuel-air ratio in the combustion zone at simulated high-altitude operating conditions for a representative 5.2-pressure-ratio engine. The performance characteristics considered were combustion efficiency, operating range, and pressure loss. Results regarding the effect of fuel injector design, effect of primary-air baffles, and performance characteristics of the best models are provided.
Date: April 11, 1955
Creator: Straight, David M. & Gernon, J. Dean
Partner: UNT Libraries Government Documents Department

An experimental investigation of the base pressure characteristics of nonlifting bodies of revolution at Mach numbers from 2.73 to 4.98

Description: Report presenting an investigation in the supersonic wind tunnel to determine some of the base pressure characteristics of related bodies of revolution at zero angle of attack. Results regarding variation of pressure over the base, variation of base pressure with Reynolds number, effect of nose and afterbody shapes, variation of base pressure with Mach number, and correlation of base pressure data are provided.
Date: March 17, 1955
Creator: Reller, John O., Jr. & Hamaker, Frank M.
Partner: UNT Libraries Government Documents Department

Pressure distribution over thick tapered airfoils, NACA 81, USA 27c modified and USA 35

Description: "At the request of the United States Army Air Service, the tests reported herein were conducted in the 5-foot atmospheric wind tunnel of the Langley Memorial Aeronautical Laboratory. The object was the measurement of pressures over three representative thick, tapered airfoils which are being used on existing or forthcoming army airplanes. The results are presented in the form of pressure maps, cross-plan load and normal force coefficient curves and load contours" (p. 433).
Date: 1926
Creator: Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

The flow and force characteristics of supersonic airfoils at high subsonic speeds

Description: Report presenting an investigation at subsonic Mach numbers in the rectangular high-speed tunnel on five supersonic airfoils and, for comparison, on two subsonic airfoils. Two-dimensional data were obtained by pressure measurements and schileren photographs at angles of attack from 0 to 4 degrees for a range of Mach numbers between 0.30 and 0.90. Results regarding pressure distributions, normal-force coefficients, pitching-moment of normal-force about the quarter-chord point, drag coefficient, and unusual flow at high Mach numbers are provided.
Date: March 1947
Creator: Lindsey, W. F.; Daley, Bernard N. & Humphreys, Milton D.
Partner: UNT Libraries Government Documents Department

Preliminary experimental investigation of low-speed turbulent boundary layers in adverse pressure gradients

Description: Report presenting measurements of velocity profiles and skin friction in subsonic turbulent boundary layers with adverse pressure gradients. The skin friction in an adverse pressure gradient was found to decrease steadily with distance to a value approaching zero for the region of separation. Results regarding the mean velocity distribution and separation, comparison of experimental values with semiempirical relations, and wall shearing stress are provided.
Date: October 1953
Creator: Sandborn, Virgil A.
Partner: UNT Libraries Government Documents Department

Study of the momentum distribution of turbulent boundary layers in adverse pressure gradients

Description: Report presenting the evaluation and analysis of the mean and turbulent terms of the equations of motion and the stress tensor at four stations in a turbulent boundary layer with a progressively increasing adverse pressure gradient. Report presenting mean flow parameters, summary of velocity measurements, evaluation of wall shearing stress, shear stress distribution across boundary layer, and stress tensor are provided.
Date: January 1955
Creator: Sandborn, Virgil A. & Slogar, Raymond J.
Partner: UNT Libraries Government Documents Department

Nonmetallic diaphragms for instruments

Description: "This report, the second of a series of reports relating to the general subject of instrument diaphragms. The first report of the series was published as Technical Report no. 165, "diaphragms for aeronautic instruments," and comprised an outline of historical developments and theoretical principles. The present report relates entirely to nonmetallic diaphragms, the use of which in certain types of pressure elements has been increasing for some time" (p. 423).
Date: 1925
Creator: Eaton, H. N. & Buckingham, C. T.
Partner: UNT Libraries Government Documents Department

Some Effects of Compressibility on the Flow Through Fans and Turbines

Description: "The laws of conservation of mass, momentum, and energy are applied to the compressible flow through a two-dimensional cascade of airfoils. A fundamental relation between the ultimate upstream and downstream flow angles, the inlet Mach number, and the pressure ratio across the cascade is derived. Comparison with the corresponding relation for incompressible flow shows large differences. The fundamental relation reveals two ranges of flow angles and inlet Mach numbers, for which no ideal pressure ratio exists" (p. 123).
Date: August 1, 1945
Creator: Perl, W. & Epstein, H. T.
Partner: UNT Libraries Government Documents Department

Preliminary investigation at Mach number 1.9 of simulated wing-root inlets

Description: Report presenting an experimental investigation to study several wing-root inlet configurations at Mach number 1.9. The inlets were of triangular and rectangular shape and external compression was provided by two-dimensional wedge surfaces. Results regarding the pressure-recovery and mass-flow data, effect of inlet side plates and curved diffusers, exit and inlet total-pressure distributions, improvement of exit total-pressure profiles, and inlet tests at zero flight speed are provided.
Date: January 19, 1955
Creator: Piercy, Thomas G. & Weinstein, Maynard I.
Partner: UNT Libraries Government Documents Department

NACA Mach number indicator for use in high-speed tunnels

Description: Report presenting a description of a device for indicating stream Mach number in a high-speed tunnel. It consists of a mechanism for determining the pressure ratio that Mach number is a function of. The instrument is in service in the 8-foot high-speed tunnel and its accuracy has been found adequate for wind-tunnel requirements.
Date: July 1943
Creator: Smith, Norman F.
Partner: UNT Libraries Government Documents Department

Free-flight pressure measurements over a flare-stabilized rocket model with a modified Von Karman nose for Mach numbers up to 4.3

Description: Report presenting pressures measured during a free-flight test at zero angle of attack over a rocket model with a modified Von Karman nose in combination with a cylindrical center section and a 10 degree half-angle flare.
Date: January 13, 1958
Creator: Bland, William M., Jr. & Kolenkiewicz, Ronald
Partner: UNT Libraries Government Documents Department

Cooling characteristics of a transpiration-cooled afterburner with a porous wall of brazed and rolled wire cloth

Description: Report presenting cooling data for a transpiration-cooled afterburner with a porous combustion-chamber wall of brazed and and rolled wire cloth for a range of exhaust-gas temperatures, total flow ratios of cooling air to combustion gas, and pressure altitudes. Results regarding typical data, cooling correlation, transpiration-cooling performance, comparison of transpiration and forced-convection cooling, and pressure environment of the wire cloth are provided.
Date: August 19, 1954
Creator: Koffel, William K.
Partner: UNT Libraries Government Documents Department

Study of the pressure rise across shock waves required to separate laminar and turbulent boundary layers

Description: Results are presented of a dimensional study and an experimental investigation of the pressure rise across a shock wave which causes separation of the boundary layer on a flat plate. The experimental part of the investigation was conducted at a Mach number of 3.03 for a Reynolds number range of 2 x 10 (sup) 6 to 19 x 10 (sup) 6. The available experimental data are compared with the predictions of the present study, and the significance of the results obtained is discussed relative to certain practical design problems.
Date: September 1952
Creator: Donaldson, Coleman duP. & Lange, Roy H.
Partner: UNT Libraries Government Documents Department

A balanced diaphragm type of maximum cylinder pressure indicator

Description: A balanced diaphragm type of maximum cylinder pressure indicator was designed to give results consistent with engine operating conditions. The apparatus consists of a pressure element, a source of controlled high pressure and a neon lamp circuit. The pressure element, which is very compact, permits location of the diaphragm within 1/8 inch of the combustion chamber walls without water cooling. The neon lamp circuit used for indicating contact between the diaphragm and support facilitates the use of the apparatus with multicylinder engines.
Date: December 1930
Creator: Spanogle, J. A. & Collins, John H., Jr.
Partner: UNT Libraries Government Documents Department

Tests of the NACA 653-018 airfoil section with boundary-layer control by suction

Description: Report presenting tests of the NACA 65(sub 3)-018 airfoil section with boundary-layer control by suction in the two-dimensional low-turbulence and two-dimensional low-turbulence pressure tunnels. Results regarding the lift characteristics, flow coefficient, maximum lift, amount of air removed by boundary-layer control, pressure distributions, and boundary layer shape are provided.
Date: October 1944
Creator: Quinn, John H., Jr.
Partner: UNT Libraries Government Documents Department

Density profiles of subsonic boundary layers on a flat plate determined by x-ray and pressure measurements

Description: Report presenting an investigation of laminar, transitional, and turbulent boundary layers in a subsonic wind tunnel at two Mach numbers at various Reynolds numbers and stations along a flat plate. Comparisons are made of the density profiles obtained with a total-pressure probe of small frontal opening and by means of an X-ray absorption method and, in a few cases, by using interferometer data.
Date: February 1954
Creator: Weltmann, Ruth N. & Kuhns, Perry W.
Partner: UNT Libraries Government Documents Department

Effect of vertical location of a horizontal tail on the static longitudinal stability characteristics of a 45 degree sweptback-wing-fuselage combination of aspect ratio 8 at a Reynolds number of 4.0 x 10(exp 6)

Description: Report presenting an experimental investigation of the effects of a horizontal tail in various vertical positions on the longitudinal stability characteristics of a wing-fuselage combination of 45 degrees sweepback and aspect ratio 8 in the 19-foot pressure tunnel. Testing occurred at two wing incidence angles and various high-lift and stall-control devices at a specified Mach and Reynolds number. The horizontal tail was tested at four vertical positions.
Date: January 21, 1952
Creator: Salmi, Reino J. & Jacques, William A.
Partner: UNT Libraries Government Documents Department

Knocking combustion observed in a spark-ignition engine with simultaneous direct and Schlieren high-speed motion pictures and pressure records

Description: Simultaneous direct and Schlieren photographs at 40,000 frames per second and correlated pressure records were taken of knocking combustion in a special spark-ignition engine to ascertain the intensity of certain end-zone reactions previously noted from Schlieren photography alone. A violent propagated homogeneous autoignition, or a similar phenomenon, previously observed, was again observed. The pressure records show autoignition of varying violence before the passage of a probable detonation wave. Extensive autoignition without occurrence of gas vibrations was seen in one explosion.
Date: 1948
Creator: Osterstrom, Gordon E.
Partner: UNT Libraries Government Documents Department

Force and pressure characteristics for a series of nose inlets at Mach numbers from 1.59 to 1.99 1: conical spike all-external compression inlet with subsonic cowl lip

Description: Report presenting an experimental investigation to determine the force and pressure characteristics of a typical nose inlet ramjet configuration. It consisted of a conical spike all-external compression inlet attached to an annular subsonic diffuser. Results regarding external-flow characteristics and internal-flow characteristics are provided.
Date: January 19, 1951
Creator: Esenwein, Fred T. & Valerino, Alfred S.
Partner: UNT Libraries Government Documents Department

Method for rapid determination of pressure change for one-dimensional flow with heat transfer, friction, rotation, and area change

Description: Report presenting the development of an approximate method for rapid determination of the pressure change for subsonic flow of a compressible fluid under the simultaneous action of heat transfer, friction, rotation, and area change. The report presents the analysis involved in simplifying the momentum equation and the charts necessary for obtaining particular solutions.
Date: June 1954
Creator: Hubbartt, James E.; Slone, Henry O. & Arne, Vernon L.
Partner: UNT Libraries Government Documents Department

Two-dimensional cascade investigation of the maximum exit tangential velocity component and other flow conditions at the exit of several turbine blade designs at supercritical pressure ratios

Description: The nature of the flow at the exit of a row of turbine blades for the range of conditions represented by four different blade configurations was evaluated by the conservation-of-momentum principle using static-pressure surveys and by analysis of Schlieren photographs of the flow. It was found that for blades of the type investigated, the maximum exit tangential-velocity component is a function of the blade geometry only and can be accurately predicted by the method of characteristics. A maximum value of exit velocity coefficient is obtained at a pressure ratio immediately below that required for maximum blade loading followed by a sharp drop after maximum blade loading occurs.
Date: August 23, 1951
Creator: Hauser, Cavour H. & Plohr, Henry W.
Partner: UNT Libraries Government Documents Department

Base pressures measured on several parabolic-arc bodies of revolution in free flight at Mach numbers from 0.8 to 1.4 and at large Reynolds numbers

Description: Report presenting base pressures measured on several fin-stabilized bodies of parabolic-arc profile in free flight at a range of Mach and Reynolds numbers. The bodies varied in length but had the same afterbody ratios. Results regarding base pressure coefficients, side pressure coefficients, effect of afterbody length, and drag are provided.
Date: October 26, 1951
Creator: Katz, Ellis & Stoney, William E., Jr.
Partner: UNT Libraries Government Documents Department

Effects of external stores on the static longitudinal aerodynamic characteristics of a model of a 45 degree swept-wing fighter airplane at Mach numbers of 1.61 and 2.01

Description: Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of various external-store configurations on the longitudinal and lateral aerodynamic characteristics of a model of a 45 degree swept-wing fighter airplane. Results regarding accuracy and remarks on effects of stores are provided.
Date: August 23, 1956
Creator: Foster, Gerald V. & Driver, Cornelius
Partner: UNT Libraries Government Documents Department