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An approximate analytical method for studying entry into planetary atmospheres
Report presenting a single, ordinary, nonlinear differential equation of second order that can be used for determining entry into an exponential planetary atmosphere. The reduced equation includes various terms, some of which represent the gravity force, the centrifugal acceleration, and the lift force. A number of solutions for lifting and nonlifting vehicles entering at various initial angles are obtained from the complete nonlinear equation.
Date:
May 1958
Creator:
Chapman, Dean R.
System:
The UNT Digital Library
Droplet Impingement and Ingestion by Supersonic Nose Inlet in Subsonic Tunnel Conditions
"The amount of water in cloud droplet form ingested by a full-scale supersonic nose inlet with conical centerbody was measured in the NACA Lewis icing tunnel. Local and total water impingement rates on the cowl and centerbody surfaces were also obtained. All measurements were made with a dye-tracer technique" (p. 1).
Date:
May 1958
Creator:
Gelder, Thomas F.
System:
The UNT Digital Library
An experimental investigation of wake effects on hydro-skis
Report presenting an experimental investigation to determine the effects of planing in a wake on the forces of a planing surface and to locate desirable positions in the wake with regard to the lift and lift-drag ratio of the planing surface. Two combinations of hydro-skis were tested: one with two in tandem and one with three arranged with one hydro-ski in the front and two in the back. Results indicated that the rear hydro-ski in tandem arrangement could have large increases in lift coefficient and small improvements in lift-drag ratio compared with the regular configuration.
Date:
May 1958
Creator:
McBride, Ellis E. & Fisher, Lloyd J.
System:
The UNT Digital Library
Flight Investigation of Effects of Retreating-Blade Stall on Bending and Torsional Moments Encountered by a Helicopter Rotor Blade
Note presenting flight tests conducted with a medium-size single-rotor helicopter, one blade of which was equipped with strain gages, to determine the effects of retreating-blade stall on the rotor blade bending and torsional moments during high-speed flight and pull-up maneuvers. The results indicate that retreating-blade stall has a substantial effect on the periodic rotor blade moments. Results regarding the effect of stall in steady forward flight and effect of stall in pull-up maneuvers are provided.
Date:
May 1958
Creator:
Ludi, LeRoy H.
System:
The UNT Digital Library
General solutions for flow past slender cambered wings with swept trailing edges and calculation of additional loading due to control surfaces
Report presenting the use of the slender-wing-type analysis to obtain general expressions for the surface pressure, lift, and rolling moment for cambered wings with swept trailing edges. The results are specialized to give the additional loading due to the deflection of trailing-edge control surfaces and the loading due to a particular type of wing twist. A numerical example for aileron control is included.
Date:
May 1958
Creator:
Klunker, E. B. & Harder, Keith C.
System:
The UNT Digital Library
Measurement of the Effect of an Axial Magnetic Field on the Reynolds Number of Transition in Mercury Flowing Through a Glass Tube
Note presenting experiments conducted to determine the effect of a strong axial magnetic field on the flow of mercury through a circular channel. The magnetic induction was 15,000 gauss, and the channel was a pyrex tube 17-1/4 inches long and 0.027 inch inside diameter. The results indicated that the stabilizing effect occurred only at Reynolds number above 5,000, so that the region of practical applicability seems to be at fairly high Reynolds numbers and when there are only slight disturbances in the flow.
Date:
May 1958
Creator:
Bader, Michel & Carlson, William C. A.
System:
The UNT Digital Library
A performance analysis of methods for handling excess inlet flow at supersonic speeds
Report presenting a comparison of several methods for handling excess inlet flow for the Mach number range from 1.5 to 4.0. The following techniques were examined and evaluated: normal- and oblique-shock spillage, bypassing through an auxiliary exit, bypassing to an ejector exhaust nozzle, and bypassing the excess flow through an auxiliary ramjet engine. Charts are presented for the thrust penalties at a variety of Mach numbers.
Date:
May 1958
Creator:
Hearth, Donald P. & Connors, James F.
System:
The UNT Digital Library
Preliminary Survey of Propulsion Using Chemical Energy Stored in the Upper Atmosphere
Ram-jet cycles that use the chemical energy of dissociated oxygen for propulsion in the ionosphere are presented. After a review of the properties and compositions of the upper atmosphere, the external drag, recombination kinetics, and aerodynamic-heating problems of an orbiting ram jet are analyzed. The study indicates that the recombination ram jet might be useful for sustaining a satellite at an altitude of about 60 miles. Atmospheric composition and recombination-rate coefficients were too uncertain for more definite conclusions. The ram jet is a marginal device even in the optimistic view.
Date:
May 1958
Creator:
Baldwin, Lionel V. & Blackshear, Perry L.
System:
The UNT Digital Library
Some Measurements of Aerodynamic Forces and Moments at Subsonic Speeds on a Rectangular Wing of Aspect Ratio 2 Oscillating About the Midchord
Report presenting some measurements of the aerodynamic forces and moments on a rectangular wing of aspect ratio 2 which oscillated about the midchord. The measurements were made at four frequencies over a range of Mach and Reynolds numbers. Results regarding the calculated values of various theories and coefficients of lift and moment are provided.
Date:
May 1958
Creator:
Widmayer, Edward, Jr.; Clevenson, Sherman A. & Leadbetter, Sumner A.
System:
The UNT Digital Library
Study of ground-reaction forces measured during landing impacts of a large airplane
Report presenting the results of tests conducted on a large bomber-type airplane to determine the ground-reaction forces imposed on the main landing gear under actual landing conditions. The vertical force on the landing gear truck at which the oleopneumatic shock strut began to compress varied over a wide range. Results regarding vertical forces, drag forces, and side forces are provided.
Date:
May 1958
Creator:
Hall, Albert W.; Sawyer, Richard H. & McKay, James M.
System:
The UNT Digital Library
Summary of experimental heat-transfer measurements in turbulent flow for a Mach number range from 0.87 to 5.05
Report presenting heat-transfer measurements made in turbulent flow at a variety of Mach and Reynolds numbers through the use of an axially symmetric annular nozzle consisting of an inner shaped center body and an outer cylindrical sleeve. The results are presented as Stanton number and recovery factor as a function of Reynolds number. Stanton number was found to decrease with an increase in Reynolds number and usually decreases with an increase in Mach number.
Date:
May 1958
Creator:
Brevoort, Maurice J. & Arabian, Barbara D.
System:
The UNT Digital Library
The application of matrix methods to coordinate transformations occurring in systems studies involving large motions of aircraft
Report presenting the method and advantages of matrix algebra in setting up the geometric aspects of problems of airplane motion. The paper is divided into two parts. The first is about the aspects of matrix algebra required for use in orthogonal transformations and the other shows how to use orthogonal transformations in matrix form by applying them in several examples.
Date:
May 1957
Creator:
Doolin, Brian F.
System:
The UNT Digital Library
Appraisal of the Hazards of Friction-Spark Ignition of Aircraft Crash Fires
Note presenting a study to determine if common aircraft metals produce friction sparks capable of igniting combustibles that might be spilled in an airplane crash. Samples of aluminum, titanium, magnesium, chrome-molybdenum steel, and stainless steel were dragged over concrete and asphalt runways while a combustible mixture of gasoline, JP-4 fuel, kerosene, or preheated oil was sprayed around the sample.
Date:
May 1957
Creator:
Campbell, John A.
System:
The UNT Digital Library
Cascade investigation of a related series of 6-percent-thick guide-vane profiles and design charts
Report presenting a description of a new blade series designed to operate at near choking inlet Mach numbers and to have near maximum critical Mach numbers by employing high aerodynamic loading of the profiles in the leading-edge region. Results regarding aerodynamic characteristics and prediction of high-speed performance are provided.
Date:
May 1957
Creator:
Dunavant, James C.
System:
The UNT Digital Library
Characteristics of a 40 Degree Cone for Measuring Mach Number, Total Pressure, and Flow Angles at Supersonic Speeds
Note presenting an experimental investigation conducted to determine the characteristics of a 40 degree cone for use in the measurement of Mach number, total pressure, and flow angles. The cone had a total-pressure orifice at the apex and four equally spaced static-pressure orifices on the surface and pressure measurements were taken at a range of angles of pitch, Mach numbers, and Reynolds numbers. Results regarding cone pressure distribution, determination of Mach number, determination of total pressure, and determination of flow angles are provided.
Date:
May 1957
Creator:
Centolanzi, Frank J.
System:
The UNT Digital Library
Charts for the analysis of flow in a whirling duct
From Summary: "Charts are developed for the analysis of flow in a whirling constant-diameter duct. These charts permit the determination of the duct-exit Mach number, or the Mach number at any point along the duct, for practical ranges of duct-inlet Mach number, duct-tip Mach number, friction factor, ratio of ambient temperature to duct-flow total temperature, ratio of duct-tip radius to duct hydraulic diameter, and heat conductivity through the duct wall and surrounding material. The method of using the charts is illustrated through the computation of a sample problem."
Date:
May 1957
Creator:
Makofski, Robert A.
System:
The UNT Digital Library
Effect of bluntness on transition for a cone and a hollow cylinder at Mach 3.1
Bluntness was more effective in displacing transition downstream on a cylinder than on a cone. The downstream displacement of transition is related to the formation of a shock layer within which the Reynolds and Mach numbers are reduced and to pressure gradients that exist over the forward part of the model. Round bluntness in general had a favorable effect, whereas sharp-cornered flat bluntness above a certain size had unfavorable effects on the location of the transition point.
Date:
May 1957
Creator:
Brinich, Paul F. & Sands, Norman
System:
The UNT Digital Library
Effect of standing transverse acoustic oscillations on fuel-oxidant mixing in cylindrical combustion chambers
Vapor fuel-oxidant mixing is analyzed for standing transverse acoustic fields simulating those existing in screeching or screaming combustors. The additional mixing due to the acoustic field is shown to be a function of sound pressure and frequency, stream velocity, and turbulence. The effects of these parameters are shown graphically for a realistic range of combustor conditions. The fuel-oxidant ratio at various combustor stations is shown to have a cyclic fluctuation which is in phase with the pressure fluctuations. Possible mechanisms contributing to screech and scream are discussed.
Date:
May 1957
Creator:
Mickelsen, William R.
System:
The UNT Digital Library
Experimental Influence Coefficients and Vibration Modes of a Built-Up 45 Degree Delta-Wing Specimen
Note presenting experimental influence coefficients and vibration modes and frequencies of a built-up 45 degrees delta-wing specimen. The symmetrical and antisymmetrical static influence coefficients were obtained on a three-point support.
Date:
May 1957
Creator:
Kordes, Eldon E.; Kruszewski, Edwin T. & Weidman, Deene J.
System:
The UNT Digital Library
Experimental Study of Heat Transfer to Small Cylinders in a Subsonic, High-Temperature Gas Stream
A Nusselt-Reynolds number relation for cylindrical thermocouple wires in crossflow was obtained from the experimental determination of time constants. Tests were conducted in exhaust gas over a temperature range of 2000 to 3400 R, a Mach number range of 0.3 to 0.8, and a static-pressure range from 2/3 to 1-1/3 atmospheres, yielding a Reynolds number range of 450 to 3000. The correlation obtained is Nu=(0.428 plus or minus 0.003) times the square root of Re* with average deviations of a single observation of 8.5 percent. This relation is the same as one previously reported for room-temperature conditions.
Date:
May 1957
Creator:
Glawe, George E. & Johnson, Robert C.
System:
The UNT Digital Library
Fatigue-crack propagation and residual static strength of built-up structures
Report presenting fatigue testing conducted on box beams and tension panels in order to study some of the factors affecting fatigue-crack propagation. Static testing was also performed on box beams, on tension panels, and on two types of wings, all of which contained fatigue cracks.
Date:
May 1957
Creator:
Hardrath, Herbert F. & Whaley, Richard E.
System:
The UNT Digital Library
Lift and moment responses to penetration of sharp-edged traveling gusts, with application to penetration of weak blast waves
Report presenting calculations of the lift and moment responses to penetration of sharp-edged traveling gusts for wings in incompressible and supersonic two-dimensional flow, for wide delta and rectangular wings in supersonic flow, and for very narrow delta wings. The results of the calculations indicate that the forward speed of the gusts has a large effect on the lift- and moment-response functions.
Date:
May 1957
Creator:
Drischler, Joseph A. & Diederich, Franklin W.
System:
The UNT Digital Library
Nonuniformities in Shock-Tube Flow Due to Unsteady-Boundary-Layer Action
Note presenting an evaluation of the boundary layer along the walls of a shock tube, which induces pressure and velocity gradients within the core of potential flow.
Date:
May 1957
Creator:
Mirels, Harold & Braun, W. H.
System:
The UNT Digital Library
On flow of electrically conducting fluids over a flat plate in the presence of a transverse magnetic field
Report presenting a study of the use of a magnetic field to control the motion of electrically conducting fluids. Results indicated that the skin friction and heat-transfer rate are reduced when the transverse magnetic field is fixed relative to the plate and increased when fixed relative to the fluid.
Date:
May 1957
Creator:
Rossow, Vernon J.
System:
The UNT Digital Library