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Use of Aerodynamic Heating to Provide Thrust by Vaporization of Surface Coolants

Description: Note presenting an analysis of the propulsive thrust and specific impulse attainable by cooling aircraft surfaces with liquefied or solidified gases with vaporization temperatures lower than the equilibrium surface temperature. Use of coolant vaporization as the sole means of propulsion yields low specific impulses at low speeds.
Date: February 1954
Creator: Moeckel, W. E.
Item Type: Refine your search to only Report
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The use of an uncalibrated cone for determination of flow angles and Mach numbers at supersonic speeds

Description: Report presenting a pressure-distribution investigation of a body of revolution in the 4- by 4-foot supersonic tunnel at a Mach number of 1.59. Results regarding the basic pressure-distribution data, reduction of conical-pitot-yaw-head data, four-static orifice system, flow-angle determination, other orifice systems, and general comments on theoretical prediction of pressure distribution on cone surfaces are provided.
Date: March 1951
Creator: Cooper, Morton & Webster, Robert A.
Item Type: Refine your search to only Report
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Use of electric analog for calculation of temperature distribution of cooled turbine blades

Description: Report presenting an investigation to develop simple, inexpensive electric analogs for determining temperatures of cooled turbine blades. Analogs were made for a 13-fin shell-supported air-cooled blade, a strut-supported air-cooled blade, and a liquid-cooled blade.
Date: December 1953
Creator: Ellerbrock, Herman H., Jr.; Schum, Eugene F. & Nachtigall, Alfred J.
Item Type: Refine your search to only Report
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Use of Nonlinearities to Compensate for the Effects of a Rate-Limited Servo on the Response of an Automatically Controlled Aircraft

Description: Report presenting a simple method for determining the nonlinear gains required to give optimum responses for step inputs of all magnitudes. The method is based on the fact that the control surface moves at its maximum rate during almost the entire transient maneuver and thus the servo system can be considered as a simple on-off type controller.
Date: January 1955
Creator: Schmidt, Stanley F. & Triplett, William C.
Item Type: Refine your search to only Report
open access

The use of perforated inlets for efficient supersonic diffusion

Description: Report presenting the use of wall perforations on supersonic diffusers to avoid the internal contraction-ratio limitation. Experimental results on a preliminary model of a perforated diffuser at Mach number 1.85 are provided. A theoretical discussion of the flow coefficients and the size and spacing of the perforations are included.
Date: September 1956
Creator: Evvard, John C. & Blakey, John W.
Item Type: Refine your search to only Report
open access

The use of pure twist for drag reduction on arrow wings with subsonic leading edges

Description: Report presenting linearized-theory calculations of the drag reduction achieved by applying the first three terms of a power series for twist to flat delta wings. For the family of wings investigated, the maximum drag reduction is 2 percent in the medium sweepback range with a steady diminution in both directions. Results for the delta and arrow wings and the optimum settings are provided.
Date: August 1957
Creator: Grant, Frederick C.
Item Type: Refine your search to only Report
open access

Use of Short Flat Vanes for Producing Efficient Wide-Angle Two-Dimensional Subsonic Diffusers

Description: "An investigation of the use of flat vanes in two-dimensional subsonic diffusers was made. Using optimum designs of vane installations, high pressure recoveries and steady flows were obtained for diffuser-wall divergence angles up to 42 degrees. Criteria for optimum configurations were developed which indicated that the vanes should be symmetrically arranged in the vicinity of the diffuser throat, that the vane-passage divergence angle should be approximately 7.0 degrees, and that the vanes sho… more
Date: September 1958
Creator: Cochran, D. L. & Kline, S. J.
Item Type: Refine your search to only Report
open access

Use of the Boundary Layer of a Cone to Measure Supersonic Flow Inclination

Description: Note presenting a description of an instrument for the measurement of supersonic flow inclination, taking advantage of the effect of angle of attack on the meridional velocity profile of the laminar boundary layer on a cone. The effect of angle of attack may be measured by the difference of total pressure recorded by two probes pointing toward the apex and located in the plane of symmetry of the flow. Results of a single test are presented and discussed.
Date: June 1952
Creator: Moore, Franklin K.
Item Type: Refine your search to only Report
open access

Use of the Coanda effect for jet deflection and vertical lift with multiple-flat-plate and curved-plate deflection surfaces

Description: Report presenting an evaluation of the ratios of lift and axial thrust to undeflected thrust of nozzle-deflection-plate configurations using the Coanda effect for obtaining jet deflection and lift. Results regarding the performance of Coanda nozzles and a comparison of performance for all Coanda nozzles tested are provided.
Date: September 1958
Creator: von Glahn, Uwe H.
Item Type: Refine your search to only Report
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Use of the Coanda effect for obtaining jet deflection and lift with a single flat-plate deflection surface

Description: Report presenting an evaluation of lift and axial thrust to undeflected thrust of nozzle-deflection-plate configurations using the Coanda effect for obtaining jet deflection and lift. This investigation focused primarily on pressure distributions over the surface of a single flat-plate deflection surface.
Date: June 1958
Creator: von Glahn, Uwe H.
Item Type: Refine your search to only Report
open access

Use of the Kernel function in a three-dimensional flutter analysis with application to a flutter-tested delta-wing model

Description: Report presenting the development and numerical application of a Rayleigh-Ritz, or modal, type of flutter analysis which takes three-dimensional structure and aerodynamic behavior into account. The application is made to a delta semispan wing with a leading-edge sweep angle of 45 degrees which fluttered at a Mach number of 0.85.
Date: September 1958
Creator: Woolston, Donald S. & Sewall, John L.
Item Type: Refine your search to only Report
open access

Use of two-dimensional data in estimating loads on a 45 degree sweptback wing with slats and partial-span flaps

Description: Report presenting a study of the application of two-dimensional data and span-loading theory for estimating the local loading characteristics on a swept wing with flaps. Estimated results are compared with results measured at large scale on a 45 degree sweptback wing of aspect ratio 6 with a 0.4-span double-slotted flap. Results regarding chordwise loading, spanwise loading, and local lift curves are provided.
Date: November 1953
Creator: Hunton, Lynn W. & James, Harry A.
Item Type: Refine your search to only Report
open access

Vapor-Phase Oxidation and Spontaneous Ignition-Correlation and Effect of Variables

Description: Note presenting the spontaneous ignition temperatures of eight structurally different hydrocarbons, which were correlated with the behavior of the same hydrocarbons toward vapor-phase oxidation. The results indicated that reducing the stoichiometry of a hydrocarbon-oxygen gas mixture to less than unity decreases the extent of oxidation, other conditions remaining unchanged.
Date: April 1956
Creator: Swarts, Donald E. & Orchin, Milton
Item Type: Refine your search to only Report
open access

Vaporization rates and drag coefficients for isooctane sprays in turbulent air streams

Description: Report presenting the use of a droplet camera developed at the NACA Lewis laboratory to obtain drop-size distribution and drop-velocity data for isooctane injected from a simple orifice directly into a turbulent air stream. Vaporization and drag coefficients were calculated for isooctane drops accelerating and evaporating in streams with velocities of 140 and 180 feet per second. Results regarding the vaporization-rate equations, drop-size-distribution analyses, analysis of drop-velocity data, … more
Date: October 1954
Creator: Ingebo, Robert D.
Item Type: Refine your search to only Report
open access

A variable-frequency light synchronized with a high-speed motion-picture camera to provide very short exposure times

Description: Report discussing a new high-speed photographic technique, which employs a variable-frequency light synchronized with a commercially available 16-millimeter high-speed motion-picture camera without appreciable alterations to the camera. The technique is described and results obtained by the technique of photographing the flow past models in a wind tunnel with the schileren method of flow visualization are presented.
Date: May 1953
Creator: Lindsey, Walter F. & Burlock, Joseph
Item Type: Refine your search to only Report
open access

Variation of boundary-layer transition with heat transfer on two bodies of revolution at a Mach number of 3.12

Description: Report presenting an investigation at Mach number 3.12 to determine the effects of heat transfer on boundary-layer transition. Data were obtained from a cone cylinder and a parabolic-nosed cylinder at a range of Reynolds numbers based on body length. Results regarding the effect on transition of surface cooling, cold-wall data, and turbulent flow are provided.
Date: September 1955
Creator: Jack, John R. & Diaconis, N. S.
Item Type: Refine your search to only Report
open access

Variation of Local Liquid-Water Concentration About an Ellipsoid of Fineness Ratio 10 Moving in a Droplet Field

Description: From Summary: "Trajectories of water droplets about an ellipsoid of revolution with a fineness ratio of 10 (10 percent thick) in flight through a droplet field were computed with the aid of a differential analyzer. Analyses of these trajectories indicate that the local concentration of liquid water at various points about an ellipsoid varies considerably and under some conditions may be several times the free-stream concentration. Curves of the local concentration factor as a function of spatia… more
Date: April 1955
Creator: Brun, Rinaldo J. & Dorsch, Robert G.
Item Type: Refine your search to only Report
open access

Variation of Local Liquid-Water Concentration About and Ellipsoid of Fineness Ratio 5 Moving in a Droplet Field

Description: From Summary: "Trajectories of water droplets about an ellipsoid of revolution with a fineness ratio of 5 (which often approximates the shape of an aircraft fuselage or missile) were computed with the aid of a differential analyzer. Analyses of these trajectories indicate that the local concentration of liquid water at various points about an ellipsoid in flight through a droplet field varies considerably and under some conditions may be several times the free-stream concentration."
Date: July 1954
Creator: Dorsch, Robert G. & Brun, Rinaldo J.
Item Type: Refine your search to only Report
open access

A variational theorem for creep with applications to plates and columns

Description: From Summary: "A variational theorem is presented for a body undergoing creep. Solutions to problems of creep bending and creep collapse of plates, columns, beams, and shells can be obtained by means of the direct methods of the calculus of variations in conjunction with the stated theorem. The application of the theorem is illustrated for plates and columns by the solution of two sample problems."
Date: May 1957
Creator: Sanders, J. Lyell, Jr.; McComb, Harvey G., Jr. & Schlechte, Floyd R.
Item Type: Refine your search to only Report
open access

A vector study of linearized supersonic flow applications to nonplanar problems

Description: Report presenting a vector study of the partial-differential equation of steady linearized supersonic flow. General expressions are derived which relate the velocity potential in the stream to the conditions on the disturbing surfaces. A discussion of problems dealing with planar bodies is given and the conditions for the solution to be unique are investigated.
Date: June 1952
Creator: Martin, John C.
Item Type: Refine your search to only Report
open access

Velocity and friction characteristics of laminar viscous boundary-layer and channel flow over surfaces with ejection or suction

Description: Report presenting some information on flow characteristics - velocity field, pressure drop, and friction - for steady, fully developed laminar flow through a duct consisting of two parallel walls, for flow throguh tubes with circular cross section, and for boundary-layer flow over infinite wedges. In order to determine the extent to which the boundary conditions imposed o the flow by the various geometries influence the flow characteristics, dimensionless parameters common to both channel and b… more
Date: December 1957
Creator: Eckert, E. R. G.; Donoughe, Patrick L. & Moore, Betty Jo
Item Type: Refine your search to only Report
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