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Effect of the Acceleration of Elongated Bodies of Revolution Upon the Resistance in a Compressible Flow

Description: The problem of the motion of an elongated body of revolution in an incompressible fluid may, as is known, be solved approximately with the aid of the distribution of sources along the axis of the body. In determining the velocity field, the question of whether the body moves uniformly or with an acceleration is no factor in the problem. The presence of acceleration must be taken into account in determining the pressures acting on the body. The resistance of the body arising from the accelerated motion may be computed either directly on the basis of these pressures or with the aid of the so-called associated masses (inertia coefficients). A different condition holds in the case of the motion of bodies in a compressible gas. In this case the finite velocity of sound must be taken into account.
Date: May 1949
Creator: Frankl, F. I.
Partner: UNT Libraries Government Documents Department

Experimental Pressure Distribution on Fuselage Nose and Pilot Canopy of Supersonic Airplane at Mach Number 1.90

Description: An investigation of the pressure distribution on the fuselage nose and the pilot canopy of a supersonic airplane model has been conducted at a Mach number of 1.90 over a wide range of angles of attack and yaw. Boundary layer separation apparently occurred from the upper surface at angles of attack above 24 degrees and from the lower surface at minus 15 degrees. No separation from the sides of the fuselage was evident at yaw angles up to 12 degrees.
Date: October 15, 1948
Creator: Wyatt, DeMarquis D.
Partner: UNT Libraries Government Documents Department

Altitude Starting Tests of a 1000-Pound-Thrust Solid-Propellant Rocket

Description: Four solid-propellant rocket engines of nominal 1000-pound-thrust were tested for starting characteristics at pressure altitudes ranging from 112,500 to 123,000 feet and at a temperature of -75 F. All engines ignited and operated successfully. Average chamber pressures ranged from 1060 to ll90 pounds per square inch absolute with action times from 1.51 to 1.64 seconds and ignition delays from 0.070 t o approximately 0.088 second. The chamber pressures and action times were near the specifications, but the ignition delay was almost twice the specified value of 0.040 second.
Date: August 27, 1952
Creator: Sloop, John L.; Rollbuhler, R. James & Krawczonek, Eugene M.
Partner: UNT Libraries Government Documents Department

Investigation of separated flows in supersonic and subsonic streams with emphasis on the effect of transition

Description: Report presents the results of experimental and theoretical research conducted on flow separation associated with steps, bases, compression corners, curved surfaces, shock-wave boundary-layer reflections, and configurations producing leading-edge separation. Results were obtained from pressure-distribution measurements, shadowgraph observations, high-speed motion pictures, and oil-film studies. The maximum scope of measurement encompassed Mach numbers between 0.4 and 3.6, and length Reynolds numbers between 4,000 and 5,000,000.
Date: November 29, 1956
Creator: Chapman, Dean R.; Kuehn, Donald M. & Larson, Howard K.
Partner: UNT Libraries Government Documents Department

Pressure distributions on triangular and rectangular wings to high angles of attack Mach numbers 1.45 and 1.97

Description: Pressure distributions were measured over rectangular wings of aspect ratio 2 and triangular wings of aspect ratios 2 and 4 at Mach numbers of 1.45 and 1.97. The investigation includes some comparison of the effects of Reynolds number and of thickening the wing root sections on the loading.
Date: June 25, 1954
Creator: Kaattari, George E.
Partner: UNT Libraries Government Documents Department

Pressure distributions on triangular and rectangular wings to high angles of attack Mach numbers 2.46 and 3.36

Description: Pressure distributions were measured over rectangular wings of aspect ratio 2 and triangular wings of aspect ratios 2 and 4 at Mach numbers of 2.46 and 3.36. The investigation includes some comparison of the effects of Mach number, Reynolds number, and thickening the wing root sections on the loading.
Date: January 18, 1955
Creator: Kaattari, George E.
Partner: UNT Libraries Government Documents Department

Pressure-distribution measurements of a low-drag airfoil with slotted flap submitted by Curtiss-Wright Corporation

Description: From Summary: "Pressure-distribution measurements were made at the request of the Materiel Division, U.S. Army Air Corps, on a 24-inch-chord wooden model equipped with a slotted flap and submitted by the Curtiss-Wright Corporation. The tests were made in the Langley two-dimensional tunnel at a Reynolds number of about 5,600,000."
Date: December 1941
Creator: Abbott, I. H.
Partner: UNT Libraries Government Documents Department

Measurements in flight of the pressure distribution on the right wing of a pursuit-type airplane at several values of Mach number

Description: Pressure-distribution measurements were made on the right wing of a pursuit-type airplane at values of Mach number up to 0.80. The results showed that a considerable portion of the lift was carried by components of the airplane other than the wings, and that the proportion of lift carried by the wings may vary considerably with Mach number, thus changing the bending moment at the wing root whether or not there is a shift in the lateral position of the center of pressure. It was also shown that the center of pressure does not necessarily move outward at high Mach numbers, even though the wing-thickness ratio decreases toward the wing tip. The wing pitching-moment coefficient increased sharply in a negative direction at a Mach lift-curve slope increased with Mach number up to values of above the critical value. Pressures inside the wing were small and negative.
Date: 1946
Creator: Clousing, Lawrence A.; Turner, William N. & Rolls, L. Stewart
Partner: UNT Libraries Government Documents Department

Full scale span load distribution on a tapered wing with split flaps of various spans

Description: Pressure-distribution tests were conducted in the full-scale wind tunnel on a 2:1 tapered U.S.A. 45 airfoil equipped with 20 percent chord split trailing-edge flaps of various spans. A special installation was employed in the tests utilizing a half-span airfoil mounted vertically above a reflection plane. The airfoil has a constant chord center section and rounded tips and is tapered in thickness from 18 percent c at the root to 9 percent c at the tip. The aerodynamic characteristics, given by the usual dimension less coefficients, are presented graphically as functions of flap span and angle of attack as well as by semispan load diagrams. The results indicate, in general, that only a relatively small increase in the normal-force coefficient is to be expected by extending the flap span of an airfoil-flap combination, similar to the one tested, beyond 70 percent of the wing span.
Date: February 1937
Creator: Parsons, John F. & Silverstein, Abe
Partner: UNT Libraries Government Documents Department

Full-scale force and pressure-distribution tests on a tapered U.S.A. 45 airfoil

Description: This report presents the results of force and pressure-distribution tests on a 2:1 tapered USA 45 airfoil as determined in the full-scale wind tunnel. The airfoil has a constant-chord center section and rounded tips and is tapered in thickness from 18 percent at the root to 9 percent at the tip. Force tests were made throughout a Reynolds Number range of approximately 2,000,000 to 8,000,000 providing data on the scale effect in addition to the conventional characteristics. Pressure-distribution data were obtained from tests at a Reynolds Number of approximately 4,000,000. The aerodynamic characteristics given by the usual dimensionless coefficients are presented graphically.
Date: March 1935
Creator: Parsons, John F.
Partner: UNT Libraries Government Documents Department

Drag and propulsive characteristics of air-cooled engine-nacelle installations for two-engine airplanes

Description: Report presenting a study on wing-nacelle propeller arrangements using a two-engine airplane with nacelles varying in diameter. Results regarding the power-off characteristics, propulsive and overall efficiencies, power-on characteristics, and pressure distributions are provided.
Date: December 1940
Creator: Wilson, Herbert A., Jr. & Lehr, Robert R.
Partner: UNT Libraries Government Documents Department

Theoretical calculations of the supersonic pressure distribution and wave drag for a limited family of tapered sweptback wings with symmetrical parabolic-arc sections at zero lift

Description: Report presenting the study of the supersonic pressure distribution and wave drag of sweptback wings at zero lift, which has been extended by means of linearized theory to include the combined effects of plan-form taper and curvature of profile. Calculations have been made for a specific wing with a supersonic leading edge, which are applicable to a limited family of plan forms.
Date: January 1950
Creator: Kainer, Julian H.
Partner: UNT Libraries Government Documents Department

An investigation of three transonic fuselage air inlets at Mach numbers from 0.4 to 0.94 and at a Mach number of 1.19

Description: Report presenting an investigation of three air inlets designed for use at transonic speeds conducted in the 8-foot high-speed tunnel. The basis of the design of the inlets was the use of a nose which was shaped so that substream velocities are maintained on its surface for high-speed operating conditions. Results regarding impact pressure recovery, external pressure distributions, wake-survey drag, supersonic external pressure drag, and design considerations are provided.
Date: November 7, 1950
Creator: Pendley, Robert E.; Robinson, Harold L. & Williams, Claude V.
Partner: UNT Libraries Government Documents Department

An Experimental Investigation of Flow Across Tube Banks

Description: Flow across tube banks was investigated by surveys of total dynamic and static pressure by visualization of the flow through the use of titanium tetrachloride smoke, by thermocouple surveys of heated tubes, and by hot-wire surveys of both heated and unheated tubes. It was found that turbulence increased as the depth of the bank increased and that the broad wake behind each tube affected flow over the succeeding tubes.
Date: March 1942
Creator: Brevoort, M. J. & Tifford, A. N.
Partner: UNT Libraries Government Documents Department

Experimental study of loop-scavenged compression-ignition cylinder for gas-generator use

Description: Report presenting an investigation of the performance and general operating characteristics of a small single-cylinder, two-stroke-cycle, loop-scavenged engine using compression ignition at low compression ratios, high inlet-manifold temperatures and high inlet-manifold and exhaust-gas pressures. Results regarding the scavenging characteristics, power output, cylinder pressures, thermal efficiency, and exhaust measurements are provided.
Date: April 4, 1949
Creator: Foster, Hampton H.; Schuricht, F. Ralph & Tauschek, Max J.
Partner: UNT Libraries Government Documents Department

A study of effects of viscosity on flow over slender inclined bodies of revolution

Description: From Summary: "The observed flow field about slender inclined bodies of revolution is compared with the calculated characteristics based upon potential theory. The comparison is instructive in indicating the manner in which the effects of viscosity are manifest. Based on this and other studies, a method is developed to allow for viscous effects on the force and moment characteristics of bodies. The calculated force and moment characteristics of two bodies of high fineness ratio are shown to be in good agreement, for most engineering purposes, with experiment."
Date: 1951
Creator: Allen, H. Julian & Perkins, Edward W.
Partner: UNT Libraries Government Documents Department

Pressure distribution at Mach numbers up to 0.90 on a cambered and twisted wing having 40 degrees of sweepback and an aspect ratio of 10, including the effects of fences

Description: Report presenting pressure measurements on a semispan model of a cambered and twisted wing, alone and in combination with a fuselage. The wing had 40 degrees of sweepback, an aspect ratio of 10, a taper ratio of 0.4, and 5 degrees of washout at the tip. Results regarding the pressure distribution and flow separation, section characteristics, and span loading characteristics are provided.
Date: March 9, 1953
Creator: Boltz, Frederick W. & Shibata, Harry H.
Partner: UNT Libraries Government Documents Department

A comparison of the experimental and theoretical loading over triangular wings at supersonic speeds

Description: Report presenting the results of an experimental investigation of the pressure distribution over two triangular wings at supersonic speeds. The two wings which were tested had identical plan forms, 45 degrees of sweepback of the leading edge, and an aspect ratio of 4.0, but different airfoil sections. Results regarding the pressure distribution at zero lift, flow characteristics and pressure distribution at angles of attack, normal-force coefficients, and application of results to other triangular wings are provided.
Date: January 3, 1951
Creator: Boyd, John W. & Phelps, E. Ray
Partner: UNT Libraries Government Documents Department

A comparison of the experimental subsonic pressure distributions about several bodies of revolution with pressure distributions computed by means of the linearized theory

Description: "An analysis is made of the effects of compressibility on the pressure coefficients about several bodies of revolution by comparing experimentally determined pressure coefficients with corresponding pressure coefficients calculated by the use of the linearized equations of compressible flow. The results show that the theoretical methods predict the subsonic pressure-coefficient changes over the central part of the body but do not predict the pressure-coefficient changes near the nose. Extrapolation of the linearized subsonic theory into the mixed subsonic-supersonic flow region fails to predict a rearward movement of the negative pressure-coefficient peak which occurs after the critical stream Mach number has been attained" (p. 1125).
Date: November 5, 1951
Creator: Matthews, Clarence W.
Partner: UNT Libraries Government Documents Department

A comparison of the experimental subsonic pressure distributions about several bodies of revolution with pressure distributions computed by means of the linearized theory

Description: Report presenting an analysis of the effects of compressibility on the pressure coefficients of several bodies of revolution by comparing experimentally determined pressure coefficients with corresponding pressure coefficients calculated by the use of linearized equations of compressible flow. The results indicated that the theoretical methods predict the subsonic pressure-coefficient changes over the central portion of the body but do not predict the pressure-coefficient changes near the nose.
Date: September 12, 1949
Creator: Matthews, Clarence W.
Partner: UNT Libraries Government Documents Department

A theory for stability and buzz pulsation amplitude in ram jets and an experimental investigation including scale effects

Description: From a theory developed on a quasi-one-dimensional-flow basis, it is found that the stability of the ram jet is dependent upon the instantaneous values of mass flow and total pressure recovery of the supersonic diffuser and immediate neighboring subsonic diffuser. Conditions for stable and unstable flow are presented. The theory developed in the report is in agreement with the experimental data of NACA-TN-3506 and NACA-RM-L50K30. A simple theory for predicting the approximate amplitude of small pressure pulsation in terms of mass-flow decrement from minimum-stable mass flow is developed and found to agree with experiments.
Date: July 28, 1953
Creator: Trimpi, Robert L.
Partner: UNT Libraries Government Documents Department

Effect of fuselage circumferential inlet location on diffuser-discharge total-pressure profiles at supersonic speeds

Description: An experimental investigation of the effect of angle of attack and inlet corrected air flow on diffuser-discharge total-pressure profiles of inlets located in various circumferential positions on a fuselage was conducted at supersonic speeds. Results indicated that the diffuser total-pressure profiles for a bottom inlet were least affected by angle of attack on distortion level was obtained with a side inlet. Variation in distortion for top inlets with angle of attack was confined to the supercritical range of inlet operation.
Date: October 29, 1956
Creator: Kremzier, Emil J. & Wasserbauer, Joseph F.
Partner: UNT Libraries Government Documents Department

Pressure Distribution on the Fuselage of a Midwing Airplane Model at High Speeds

Description: Report presenting the pressure distribution on the fuselage of a midwing airplane model measured in the 8-foot high-speed wind tunnel at a range of speeds and lift coefficients. The primary purpose of the investigation was to provide data showing the air pressures on various parts of the fuselage for use in structural design.
Date: February 1943
Creator: Delano, James B.
Partner: UNT Libraries Government Documents Department

Flight and wind-tunnel tests of an XBM-1 dive bomber

Description: From Summary: "Results are given of pressure-distribution measurements made in flight over the right wing cellule and the right half of the horizontal tail surfaces of a dive-bombing biplane. Simultaneous measurements were also taken of the air speed, control-surface positions, control forces, and normal accelerations during various abrupt maneuvers in vertical plane. These maneuvers consisted of push-downs and pull-ups from level flight, dives and dive pull-ups from inverted flight. Besides the pressure measurements, flight tests were made to obtain (1) wing-fabric deflections during dives and (2) variation of the minimum drag coefficient with Reynolds Number."
Date: April 1938
Creator: Donely, Philip & Pearson, Henry A.
Partner: UNT Libraries Government Documents Department