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Exact solutions of laminar-boundary-layer equations with constant property values for porous wall with variable temperature

Description: From Summary: "Exact solution of the laminar-boundary-layer equations for wedge-type flow with constant property values are presented for transpiration-cooled surfaces with variable wall temperatures. The difference between wall and stream temperature is assumed proportional to a power of the distance from the leading edge. Solutions are given for a Prandtl number of 0.7 and ranges of pressure-gradient, cooling-air-flow, and wall-temperature-gradient parameters. Boundary-layer profiles, dimensi… more
Date: July 15, 1954
Creator: Donoughe, Patrick L. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
open access

Theory of wing-body drag at supersonic speeds

Description: "The relation of Whitcomb's "area rule" to the linear formulas for wave drag at lightly supersonic speeds is discussed. By adopting an approximate relation between the source strength and the geometry of a wing-body combination, the wave-drag theory is expressed in terms involving the areas intercepted by oblique planes or Mach planes. The resulting formulas are checked by comparison with the drag measurements obtained in wind-tunnel experiments and in experiments with falling models in free ai… more
Date: July 8, 1953
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
open access

Relative importance of various sources of defect-producing hydrogen introduced into steel during application of vitreous coatings

Description: "When porcelain enamels or vitreous-type ceramic coatings are applied to ferrous metals, there is believed to be an evolution of hydrogen gas both during and after the firing operation. At elevated temperatures rapid evolution may result in blistering while if hydrogen becomes trapped in the steel during the rapid cooling following the firing operation gas pressures may be generated at the coating-metal interface and flakes of the coating literally blown off the metal. To determine experimental… more
Date: July 12, 1951
Creator: Moore, Dwight G.; Mason, Mary A. & Harrison, William N.
Partner: UNT Libraries Government Documents Department
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The Linearized Characteristics Method and Its Application to Practical Nonlinear Supersonic Problems

Description: "The methods of characteristics has been linearized by assuming that the flow field can be represented as a basic flow field determined by nonlinearized methods and a linearized superposed flow field that accounts for small changes of boundary conditions. The method has been applied to two-dimensional rotational flow where the basic flow is potential flow and to axially symmetric problems where conical flows have been used as the basic flows. In both cases the method allows the determination of… more
Date: July 24, 1951
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department
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Design of two-dimensional channels with prescribed velocity distributions along the channel walls

Description: "A general method of design is developed for two-dimensional unbranched channels with prescribed velocities as a function of arc length along the channel walls. The method is developed for both compressible and incompressible, irrotational, nonviscous flow and applies to the design of elbows, diffusers, nozzles, and so forth. In part I solutions are obtained by relaxation methods; in part II solutions are obtained by a Green's function. Five numerical examples are given in part I including thre… more
Date: July 25, 1951
Creator: Stanitz, John D.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Turbulent Free-Convection Boundary Layer on Flat Plate

Description: "With the use of Karman's integrated momentum equation for the boundary layer and data on the wall-shearing stress and heat transfer in forced-convection flow, a calculation was carried out for the flow and heat transfer in the turbulent free-convection boundary layer on a vertical flat plate. The calculation is for a fluid with a Prandtl number that is close to 1. A formula was derived for the heat-transfer coefficient that was in good agreement with experimental data in the range of Grashof n… more
Date: July 12, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
Partner: UNT Libraries Government Documents Department
open access

Characteristics of the Langley 8-Foot Transonic Tunnel With Slotted Test Section

Description: "A large wind tunnel, approximately 8 feet in diameter, has been converted to transonic operation by means of slots in the boundary extending in the direction of flow. The usefulness of such a slotted wind tunnel, already known with respect to the reduction of the subsonic blockage interference and the production of continuously variable supersonic flows, has been augmented by devising a slot shape with which a supersonic test region with excellent flow quality could be produced. Experimental l… more
Date: July 3, 1958
Creator: Wright, Ray H.; Ritchie, Virgil S. & Pearson, Albin O.
Partner: UNT Libraries Government Documents Department
open access

Elliptic Cones Alone and with Wings at Supersonic Speed

Description: "To help fill the gap in the knowledge of aerodynamics of shapes intermediate between bodies of revolution and flat triangular wings, force and moment characteristics for elliptic cones have been experimentally determined for Mach numbers of 1.97 and 2.94. Elliptic cones having cross-sectional axis ratios from 1 through 6 and with lengths and base areas equal to circular cones of fineness ratios 3.67 and 5 have been studied for angles of bank of 0 degree and 90 degrees. Elliptic and circular co… more
Date: July 17, 1957
Creator: Jorgensen, Leland H.
Partner: UNT Libraries Government Documents Department
open access

Measurements of free-space oscillating pressures near propellers at flight Mach numbers to 0.72

Description: "In the course of a short flight program initiated to check the theory of Garrick and Watkins (NACA rep. 1198), a series of measurements at three stations were made of the oscillating pressures near a tapered-blade plan-form propeller and rectangular-blade plan form propeller at flight Mach numbers up to 0.72. In contradiction to the results for the propeller studied in NACA rep. 1198, the oscillating pressures in the plane ahead of the propeller were found to be higher than those immediately b… more
Date: July 1, 1958
Creator: Kurbjun, Max C. & Vogeley, Arthur W.
Partner: UNT Libraries Government Documents Department
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Comparison of effectiveness of convection-, transpiration-, and film-cooling methods with air as coolant

Description: From Summary: "Various parts of aircraft propulsion engines that are in contact with hot gases often require cooling. Transpiration and film cooling, new methods that supposedly utilize cooling air more effectively than conventional convection cooling, have already been proposed. This report presents material necessary for a comparison of the cooling requirements of these three methods. Correlations that are regarded by the authors as the most reliable today are employed in evaluating each of t… more
Date: July 9, 1953
Creator: Eckert, E. R. G. & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
open access

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… more
Date: July 28, 1953
Creator: Trimpi, Robert L.
Partner: UNT Libraries Government Documents Department
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Summary of derived gust velocities obtained from measurements within thunderstorms

Description: Available measurements of the derived gust velocities within thunderstorms are summarized for altitudes from 5,000 to 34,000 feet. The results indicate that the intensity of the derived gust velocity is essentially constant up to altitudes of 20,000 feet and that an approximate 10-percent reduction in the gust intensity occurs for altitudes from 20,000 to 30,000 feet.
Date: July 27, 1955
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department
open access

Lift and center of pressure of wing-body-tail combinations at subsonic, transonic, and supersonic speeds

Description: From Summary: "A method is presented for calculating the lift and centers of pressure of wing-body and wing-body-tail combinations at subsonic, transonic, and supersonic speeds. A set of design charts and a computing table are presented which reduce the computations to routine operations. Comparison between the estimated and experimental characteristics for a number of wing-body and wing-body-tail combinations shows correlation to within + or - 10 percent on lift and to within about + or - 0.02… more
Date: July 8, 1953
Creator: Pitts, William C.; Nielsen, Jack N. & Kaattari, George E.
Partner: UNT Libraries Government Documents Department
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