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Direct Measurements of Skin Friction

Description: Note presenting a device developed to measure local skin friction on a flat plate by measuring the force exerted upon a very small movable part of the surface of a flat plate. The device is applied to both low-speed and high-speed measurements. The paper describes the design and construction of the device and the results of the measurements.
Date: January 1952
Creator: Dhawan, Satish
Partner: UNT Libraries Government Documents Department

A Preliminary Investigation of High-Speed Impact the Penetration of Small Spheres Into Thick Copper Targets

Description: Small metal spheres of various densities were fired at high speed into thick targets of copper and lead. In general, it was found that all of the penetrations could be correlated quite well for engineering purposes by a function relating the depth of penetration to the impact momentum per unit volume.
Date: May 28, 1958
Creator: Charters, A. C. & Locke, G. S., Jr.
Partner: UNT Libraries Government Documents Department

Direct Measurements of Skin Friction

Description: "A device has been developed to measure local skin friction on a flat plate by measuring the force exerted upon a very small movable part of the surface of the flat plate. These forces, which range from about 1 milligram to about 100 milligrams, are measured by means of a reactance device. The apparatus was first applied to measurements in the low-speed range, both for laminar and turbulent boundary layers. The device was then applied to high-speed subsonic flow and the turbulent-skin-friction coefficients were determined up to a Mach number of about 0.8" (p. 281).
Date: June 1, 1951
Creator: Dhawan, Satish
Partner: UNT Libraries Government Documents Department

Turbulent Skin Friction at High Mach Numbers and Reynolds Numbers

Description: From Summary: "For a number of years now, experimenters have been making measurements of skin friction. Formerly, the main interest was at low Mach numbers; later, measurements were made at supersonic Mach numbers. However, almost all of these measurements were over a limited range of Reynolds numbers. On the other hand, these measurements fairly well determined the effects of Mach number and heat transfer on skin friction. The purpose of this paper is to give the results of skin-friction measurements in turbulent boundary layers at high Mach numbers and high Reynolds numbers where data have not previously existed."
Date: July 24, 1958
Creator: Matting, Fred W. & Chapman, Dean R.
Partner: UNT Libraries Government Documents Department

Skin-friction drag and boundary-layer transition on a parabolic body of revolution (NACA RM-10)at a Mach number of 1.6 in the Langley 4-by-4 foot supersonic pressure tunnel

Description: Report presenting an investigation at Mach number 1.6 and a range of Reynolds number of the skin-friction drag and boundary-layer transition of a body of revolution. The body had a parabolic-arc profile, a blunt base, and a fineness ratio of 12.2 (NACA RM-10). Results regarding the effect of surface condition, drag breakdown, and results of boundary-layer surveys are provided.
Date: May 20, 1952
Creator: Czarnecki, K. R. & Marte, Jack E.
Partner: UNT Libraries Government Documents Department

Effects of fabrication-type roughness on turbulent skin friction at supersonic speeds

Description: Report presenting an investigation of the effects of fabrication-type surface roughness on turbulent skin-friction drag at supersonic speeds. It was found that fabrication of the thin-skin constructions could be done sufficiently well in practice so as to cause no increase in drag over the smooth body; however, the juncture-type roughnesses produced significant increases in drag as compared with the smooth body. Results indicated that increasing the unit Reynolds number has a detrimental effect and increased the Mach number has a powerful alleviating effect on drag due to surface roughness.
Date: July 1958
Creator: Czarnecki, K. R.; Sevier, John R., Jr. & Carmel, Melvin M.
Partner: UNT Libraries Government Documents Department

Free-Flight Skin Temperature and Pressure Measurements on a Slightly Blunted 25 Deg Cone-Cylinder-Flare Configuration to a Mach Number of 9.89

Description: "Skin temperatures and surface pressures have been measured on a slightly blunted cone-cylinder-flare configuration to a maximum Mach number of 9.89 with a rocket-propelled model. The cone had a total angle of 25 deg and the flare had a 10 deg half-angle. Temperature data were obtained at eight cone locations, four cylinder locations, and seven flare locations; pressures were measured at one cone location, one cylinder location, and three flare locations" (p. 1).
Date: April 10, 1957
Creator: Bond, Aleck C. & Rumsey, Charles B.
Partner: UNT Libraries Government Documents Department

Free-flight skin-temperature and surface-pressure measurements on a highly polished nose having a 100 degree total-angle cone and a 10 degree half-angle conical flare section up to a Mach number of 4.08

Description: Report presenting measurements of the skin temperature and surface pressure on a large-scale, highly polished nose with a relatively sharp-tipped 100 degree total-angle cone followed by a conical flare section of 10 degree half-angle. Heating on the forward 3.0 to 4.5 inches of the 100 degrees cone was generally lower than that on the rearward portion.
Date: August 23, 1957
Creator: Rashis, Bernard & Bond, Aleck C.
Partner: UNT Libraries Government Documents Department

Effects of simulated skin wrinkles on the wing surface on the aerodynamic characteristics of two wing-body combinations employing wings of low aspect ratio at subsonic and supersonic speeds

Description: Report presenting the results of an investigation to determine the effects of simulated skin wrinkling of the wing surface on the aerodynamic characteristics of two wing-body combinations. The lift, drag, and pitching moment of a low-wing wing-body combination with a plane triangular wing of aspect ratio 3 are presented for a range of Mach and Reynolds numbers.
Date: August 5, 1952
Creator: Heitmeyer, John C. & Smith, Willard G.
Partner: UNT Libraries Government Documents Department

Average skin-friction coefficients from boundary-layer measurements in flight on a parabolic body of revolution (NACA RM-10) at supersonic speeds and at large Reynolds numbers

Description: Report presenting boundary-layer measurements on rocket-powered free-flight models to determine average skin-friction coefficients. The test body, NACA RM-10, was a fin-stabilized parabolic body of revolution of fineness ratio 12.2 with a blunt base to provide space for a rocket jet. Results regarding the skin-friction and boundary-layer profiles and experimental and theoretical curves are provided.
Date: March 7, 1951
Creator: Rumsey, Charles B. & Loposer, J. Dan
Partner: UNT Libraries Government Documents Department

Investigation of distributed surface roughness on a body of revolution at a Mach number of 1.61

Description: Report presenting an investigation of the effects of distributed surface roughness, consisting of lathe-tool marks, on the skin-friction drag of a body of revolution at Mach number 1.61. Tests were conducted on ogive-cylinders at zero angle of attack over a range of roughness and Reynolds number. The results indicate that the effects of surface roughness are generally similar to those found at subsonic speeds.
Date: June 1954
Creator: Czarnecki, K. R.; Robinson, Ross B. & Hilton, John H., Jr.
Partner: UNT Libraries Government Documents Department

Skin frictional resistance of plane surfaces in air: Abstract of recent German tests, with notes

Description: Given here is the most recent research on skin frictional resistance of plane surfaces in air that was conducted by Dr. Wieselsberger under the direction of Dr. Prandtl of Gottingen University. In all, 16 models were tested. These were divided into four groups, as follows: 1) cloth, in the original condition; 2) cloth, with the nap singed off; 3) cloth, with three coats of dope; and 4) cloth, with six coats of dope. Each group consisted of four models of uniform width, 1 meter, and of lengths of 0.5, 1.0, 1.5, and 2.0 meters.
Date: July 1922
Creator: Diehl, W. S.
Partner: UNT Libraries Government Documents Department

High-Speed Investigation of Skin Wrinkles on Two NACA Airfoils

Description: Note presenting an investigation of the effects on the aerodynamic characteristics of skin wrinkles on the forward part of the upper surface of two NACA airfoils. The results showed that no appreciable change in normal-force or pitching-moment characteristics over the range of Mach numbers tested was noted. The drag was greater on the wrinkled sections than the smooth sections, however.
Date: August 1946
Creator: Robinson, Harold L.
Partner: UNT Libraries Government Documents Department

Skin-Temperature Telemeter for Determining Boundary-Layer Heat-Transfer Coefficients

Description: Memorandum presenting a description of a method of telemetering skin temperature using a small resistance wire pickup with a time constant of less than 0.003 second to determine boundary-layer heat-transfer coefficients. An evaluation of the accuracy of the method of measuring the heat-transfer coefficient is given for a particular application.
Date: March 15, 1951
Creator: Fricke, Clifford L. & Smith, Francis B.
Partner: UNT Libraries Government Documents Department

Pressure and Frictional Resistance of a Cylinder at Reynolds Numbers 5,000 to 40,000

Description: This report presents the results of a series of free-jet measurements to determine the pure frictional resistance of a cylinder from the difference between total resistance and pressure at Reynolds Numbers 5,000 to 40,700. The skin friction is 5 percent of the total resistance at Re = 5,000, and had dropped to 2 percent at Re = 40,000, which supports Thom's theory.
Date: July 1933
Creator: Schiller, L. & Linke, W.
Partner: UNT Libraries Government Documents Department

Contributions to the Theory of Incomplete Tension Bay

Description: The present report offers an approximate theory for the stress and deformation condition after buckling of the skin in reinforced panels and shells loaded in simple shear and compression and under combined stresses. The theory presents a unified scheme for stresses of these types. It is based upon the concept of a nonuniform stress distribution in the metal panel and its marked power of resistance against compressive stresses ("incomplete" tension bay).
Date: July 1937
Creator: Schapitz, E.
Partner: UNT Libraries Government Documents Department

On the Form of the Turbulent Skin-Friction Law and Its Extension to Compressible Flows

Description: "A derivation of the form of the incompressible turbulent skin-friction law for an insulated flat plate is made in such a way that it may be extended to compressible flows. The ratio of compressible to incompressible skin friction is obtained, and the results are shown to be in agreement with existing experimental results" (p. 1).
Date: May 1952
Creator: Donaldson, Coleman duP.
Partner: UNT Libraries Government Documents Department

An investigation of the effects of rapid skin heating on box beams loaded in bending

Description: Report presenting testing of two beams of three web types which were loading in bending and subjected to rapid skin heating at rates from about 50 to 70 degrees Fahrenheit per second. The investigation was meant to determine some of the effects that rapid skin heating would have on the buckling and failing strength of multiweb-wing structures. The three types of web tested included the channel web, corrugated web, and truss web.
Date: March 23, 1955
Creator: Pride, Richard A.
Partner: UNT Libraries Government Documents Department

A summary of available knowledge concerning skin friction and heat transfer and its application to the design of high-speed missiles

Description: Review of certain characteristics necessary to determine skin friction and heat transfer on the surfaces of high-speed missiles, including temperature recovery, skin-friction coefficients and heat-transfer coefficients of laminar and turbulent boundary layers, and the position of the transition from laminar to turbulent flow. A comparison is also made between existing flight data and results computed by the boundary-layer momentum-integral method in an attempt to establish design criteria for missiles that are very different from the typical shape.
Date: November 9, 1951
Creator: Rubesin, Morris W.; Rumsey, Charles B. & Varga, Steven A.
Partner: UNT Libraries Government Documents Department

Skin-friction measurements in incompressible flow

Description: Report presenting experiments conducted to measure in incompressible flow the local surface-shear stress and average skin-friction coefficient for a turbulent boundary layer on a smooth, flat plate with zero pressure gradient. Local velocity measurements and local surface-shear measurements were taken and a sensitive manometer was used.
Date: March 1958
Creator: Smith, Donald W. & Walker, John H.
Partner: UNT Libraries Government Documents Department

Critical shear stress of an infinitely long flat plate with equal elastic restraints against rotation along the parallel edges

Description: Report presenting a chart for the values of the coefficient in the formula for the critical shear stress at which buckling may be expected to occur in an infinitely long flat plate with parallel edges. An approximate method for the evaluation of the critical shear stress when the elastic restraints on the two parallel edges are not equal is also presented.
Date: November 1943
Creator: Stowell, Elbridge Z.
Partner: UNT Libraries Government Documents Department

The effect of fluid injection on the compressible turbulent boundary layer : the effect of skin friction of air injected into the boundary layer of a cone at M = 2.7

Description: Report presenting data from which the effects of transpiration air flow on average skin-friction coefficients and pressure drag of a conical model were evaluated. The model consisted of a truncated porous nose cone with a solid ogival nose section. Results regarding the pressure distribution, base pressure drag, average skin-friction coefficients, effects of transpiration air, and comparison with theory.
Date: June 19, 1956
Creator: Tendeland, Thorval & Okuno, Arthur F.
Partner: UNT Libraries Government Documents Department