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Viscosities of Air and Nitrogen at Low Pressures

Description: Note presenting information from the results of an investigation to measure the true viscosities of nitrogen and air at a range of pressures and temperatures. Results regarding the region of slip and region of free-molecule viscosity are provided.
Date: November 1951
Creator: Johnston, Herrick L.; Mattox, Robert W. & Powers, Robert W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Viscosity Corrections to Cone Probes on Rarefied Supersonic Flow at a Nominal Mach Number of 4

Description: Note presenting data obtained for the viscosity corrections to cone probes in supersonic rarefied air flow at a nominal Mach number of 4. The test models consisted of a set of seven geometrically similar 5 degree semivertex-angle cones. Results regarding cone surface pressure distributions, calibration data for geometrically similar cones, orifices size effect, and tests at other Mach numbers are provided.
Date: November 1954
Creator: Talbot, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Viscosity of diesel engine fuel oil under pressure

Description: In the development of Diesel engine fuel injection systems it is necessary to have an approximate knowledge of the absolute viscosity of the fuel oil under high hydrostatic pressures. This report presents the results of experimental tests conducted by Mr. Jackson Newton Shore, utilizing the A.S.M.E. high pressure equipment.
Date: September 1929
Creator: Hersey, Mayo D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Viscous Flows in Inlets

Description: Report discusses ways to reduce "viscous effects", which increase total pressure losses due to friction at increasing free-stream Mach numbers. Some of the effects are related to the inlet of an aircraft and potential issues in design. From Introduction: "Care must be exercised in inlet design to maintain uniform steady boundary-layer and core flows in the throat."
Date: June 30, 1958
Creator: Scherrer, Richard; Lundell, John H. & Anderson, Lewis A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Visual Observations of the Shock Wave in Flight

Description: "This report presents the results of pilot observations and photographs of the compression shock wave on the wing of an airplane in flight. A detailed description of the test conditions necessary and the procedure to be following in producing the visible shock are presented. The pilot's observations of the occurrence of an oscillating shock wave and its possible relationship with the airplane buffeting are also presented" (p. 1).
Date: May 24, 1948
Creator: Cooper, George E. & Rathert, George A., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A visual photographic study of cylinder lubrication

Description: From Summary: "A V-type engine provided with a glass cylinder was used to study visually the lubrication characteristics of an aircraft-type piston. Photographs and data were obtained with the engine motored at engine speeds up to 1000 r.p.m. and constant cylinder-head pressures of 0 and 50 pounds per square inch. A study was made of the orientation of the piston under various operating conditions, which indicated that the piston was inclined with the crown nearest the major-thrust cylinder fac… more
Date: August 1, 1945
Creator: Shaw, Milton C. & Nussdorfer, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Visual Studies of Cylinder Lubrication [Part] 1: The Lubrication of the Piston Skirt

Description: Report describes the lubrication characteristics of an aircraft-type piston as visually studied in a V-type engine with a glass cylinder. Information about the movement of the piston, the piston rings, and the oil-control rings and their effect on lubrication is included.
Date: September 1945
Creator: Shaw, Milton C. & Nussdorfer, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Visualization of rotor tip secondary flows with blade tip air discharge and suction in a low-speed turbine

Description: Smoke was used to visualize outer-wall secondary flows in a low-speed turbine utilizing rotor tip air discharge and suction. Photographs as well as visual observations of the effect of tip air discharge and suction were made by independently varying the direction and quantity of the tip air discharge and suction, and varying tip clearance, and main-stream air speed. In addition, the cross-sectional area of the hollow blade discharge opening was varied for the case of tip air discharge.
Date: August 17, 1956
Creator: Kofskey, Milton G. & Allen, Hubert W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A visualization study of secondary flows in cascades

Description: Flow-visualization techniques are employed to ascertain the streamline patterns of the nonpotential secondary flows in the boundary layers of cascades, and thereby to provide a basis for more extended analyses in turbomachines. The three-dimensional deflection of the end-wall boundary layer results in the formation of a vortex within each cascade passage. The size and tightness of the vortex generated depend upon the main-flow turning in the cascade passage. Once formed, a vortex resists turnin… more
Date: 1954
Creator: Herzig, Howard Z.; Hansen, Arthur G. & Costello, George R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Visualization study of secondary flows in turbine rotor tip regions

Description: Report presenting a visualization study using smoke to see the secondary-flow phenomena in the rotor-blade tip region of a low-speed turbine. Measurements of the factors affecting the flow patterns were recorded from visual observations. Results regarding a general description of the smoke patterns, shroud boundary-layer considerations, transition rotor tip speed, and high-speed-turbine operating conditions are provided.
Date: September 1955
Creator: Allen, Hubert W. & Kofskey, Milton G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Voltera's Solution of the Wave Equation as Applied to Three-Dimensional Supersonic Airfoil Problems

Description: "A surface integral is developed which yields solutions of the linearized partial differential equation for supersonic flow. These solutions satisfy boundary conditions arising in wing theory. Particular applications of this general method are made, using acceleration potentials, to flat surfaces and to uniformly loaded lifting surfaces. Rectangular and trapezoidal plan forms are considered along with triangular forms adaptable to swept-forward and swept-back wings. The case of the triangular p… more
Date: September 1947
Creator: Heaslet, Max A.; Lomax, Harvard & Jones, Arthur L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vortex interference on slender airplanes

Description: Report presenting formulas for the forces and moments due to vortex interference on slender wing-body-tail combinations of general cross section in terms of positions and strengths of shed vortices. The analysis is applicable to steady motion and motions which can be considered to be made up of a succession of steady states.
Date: November 1955
Creator: Sacks, Alvin H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vortex Noise From Rotating Cylindrical Rods

Description: "A series of round rods of the some diameter were rotated individually about the mid-point of each rod. Vortices are shed from the rods when in motion, giving rise to the emission of sound. With the rotating system placed in the open air, the distribution of sound in space, the acoustical power output, and the spectral distribution have been studied. The frequency of emission of vortices from any point on the rod is given by the formula of von Karman" (p. 1).
Date: February 1935
Creator: Stowell, E. Z. & Deming, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Vortex Theory and Its Significance in Aviation

Description: This report will present ideas closely related to the vortex conception and illustrate them in the simplest possible terms. In addition to these general considerations, this report will attempt to show the application of the vortex theory in connection with the wing theory.
Date: July 1930
Creator: Betz, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vortices and the Related Principles of Hydrodynamics

Description: Here, conceptions concerning vortices are illustrated by the simplest possible examples. Mathematical formulas and similar means of presentation, which, for the most part, do not help the understanding of persons not versed therein, have been avoided as much as possible. Instead, the author has endeavored to demonstrate the phenomena by means of simple geometrical and mechanical illustrations. For the sake of clarity, the author chiefly considers currents in one plane only, a situation that can… more
Date: November 1921
Creator: Betz, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vorticism in Aeronautics

Description: Since the war there has been a considerable advance in knowledge on the subject of the airfoil and its behavior. The theory is now sufficiently advanced to make it possible to predict and to calculate certain results which previously could only be attained by direct experiment. The vortex theory receives special attention.
Date: August 1923
Creator: Sayers, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wake measurements behind a wing section of a fighter airplane in fast dives

Description: Report presenting wake measurements made in a vertical plane behind a wind section of a fighter airplane for a range of Mach numbers up to 0.78. The critical Mach number of each wing section was exceeded by 0.05 before large increases in the profile-drag coefficient occurred.
Date: March 1947
Creator: Beeler, De E. & Gerard, George
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wake studies of eight model propellers

Description: Report presenting an investigation of the influences of shank form and pitch distribution on the characteristics of constant-speed propellers as determine from the wakes of eight model propellers. The experiments show that an improvement in efficiency occurs from the substitution of faired shanks for round ones, which is caused by disproportionate local augmentations of thrust and torque. Results regarding a comparison with force tests, method of comparing performance characteristics, effects o… more
Date: July 1946
Creator: Reid, Elliott G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wake Surveys in the Slipstream of a Full-Scale Supersonic-Type Three-Blade Propeller at Mach Numbers to 0.96

Description: Report presenting an investigation of the thrust loading by wake surveys in the slipstream of a full-scale supersonic-type three-blade propeller (the Curtiss-Wright 109622) that was conducted in the transonic tunnel. Integrated-thrust coefficient values were found to be in good agreement with the force data. Results regarding thrust loading at constant advance ratios, at advance ratios for maximum efficiency, and lift-coefficient distribution are also provided.
Date: October 30, 1953
Creator: Swihart, John M. & Norton, Harry T., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wall Interference in a Perforated Wind Tunnel

Description: "The theory of cascades, made up of a series of flat plates placed one behind the other, is extended to the case where the impinging stream is not uniform, and the deduced properties of this cascade-flow are then applied to the study of the wall interference between such as cascade-like boundary and a vortex-source type of singularity. It is shown that the induced velocities, produced by the presence of such a wall, are equal to what is obtained by action of a suitably chosen 'reflected' singul… more
Date: May 1957
Creator: Brescia, Riccardo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wall interference in a two-dimensional-flow wind tunnel with consideration of the effect of compressibility

Description: Report presenting tunnel-wall corrections for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid and is based on the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. The theoretical results are compared with the small amount of low-speed experimental data available and agreement is seen to be satisfactory, even for… more
Date: December 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wall interference in a two-dimensional-flow wind tunnel, with consideration of the effect of compressibility

Description: From Summary: "Theoretical tunnel-wall corrections are derived for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid, and is based upon the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. Consideration is given to the phenomenon of choking at high speeds and its relation to the tunnel-wall corrections. The theore… more
Date: 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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