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Diesel Exhaust Contamination of Tunnel Air

Description: Report issued by the Bureau of Mines on investigations of air contamination in tunnels due to diesel exhaust. Air samples were taken inside tunnels and measured for carbon dioxide, carbon monoxide, and nitrogen oxides. This report includes tables and graphs.
Date: February 1968
Creator: Holtz, John C. & Dalzell, Robert W.
Partner: UNT Libraries Government Documents Department

Analytical study of blockage- and lift-interference corrections for slotted tunnels obtained by the substitution of an equivalent homogeneous boundary for the discrete slots

Description: From Introduction: "This paper will treat the problem in the suggested manner, beginning with the development of a suitable boundary condition to represent mathematically a homogeneous boundary which has the same flow characteristics, at a point in the flow sufficiently removed from the boundary as the actual physical boundary of alternate open and closed portions of the wall. Numerical results will be presented for circular tunnels with uniformly distributed around the circumference, for rectangular tunnels with uniformly distributed around the circumference, for rectangular tunnels with uniformly distributed slots in the top and bottom walls, for rectangular tunnels with the slot distribution determined by a transformation from a uniformly slotted circular tunnel, and for a two-dimensional tunnel. The results of this paper are derived on the basis of an incompressible potential flow."
Date: June 29, 1953
Creator: Davis, Don D., Jr. & Moore, Dewey
Partner: UNT Libraries Government Documents Department

Air flow in a separating laminar boundary layer

Description: Report discussing the speed distribution in a laminar boundary layer on the surface of an elliptic cylinder, of major and minor axes 11.78 and 3.98 inches, respectively, has been determined by means of a hot-wire anemometer. The direction of the impinging air stream was parallel to the major axis. Special attention was given to the region of separation and to the exact location of the point of separation. An approximate method, developed by K. Pohlhausen for computing the speed distribution, the thickness of the layer, and the point of separation, is described in detail; and speed-distribution curves calculated by this method are presented for comparison with experiment.
Date: December 1, 1934
Creator: Schubauer, G. B.
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of eight very thick airfoils from tests in the variable density wind tunnel

Description: Report presents the results of wind tunnel tests on a group of eight very thick airfoils having sections of the same thickness as those used near the roots of tapered airfoils. The tests were made to study certain discontinuities in the characteristic curves that have been obtained from previous tests of these airfoils, and to compare the characteristics of the different sections at values of the Reynolds number comparable with those attained in flight. The discontinuities were found to disappear as the Reynolds number was increased. The results obtained from the large-scale airfoil, a symmetrical airfoil having a thickness ratio of 21 per cent, has the best general characteristics.
Date: 1932~
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of two-plane, unswept tapered wings of aspect ratio 3 and 3-percent thickness from tests on a transonic bump

Description: From Introduction: "The Ames Aeronautical Laboratory has in progress an experimental investigation of the aerodynamic characteristics of wings of interest in the design of high-speed fighter aircraft. This program included an investigation in the Ames 6-by 6-foot supersonic wind tunnel at both subsonic and supersonic Mach numbers of a wing-body combination having a 3-percent-thick, unswept, tapered wing with circular-arc sections and an aspect ratio of 3.1 (reference 1).
Date: May 2, 1952
Creator: Emerson, Horace F. & Gale, Bernard M.
Partner: UNT Libraries Government Documents Department

An analysis of longitudinal-control problems encountered in flight at transonic speeds with a jet-propelled airplane

Description: From Introduction: "This report presents an analysis based on flight and wind-tunnel test data directed toward the determination of the probable cause of the pitch-up. Wing pressure distribution and stability and control characteristics in the dive are also included."
Date: September 25, 1947
Creator: Brown, Harvey H.; Rolls, L. Stewart & Clousing, Lawrence A.
Partner: UNT Libraries Government Documents Department

Analysis of factors affecting net lift increment attainable with trailing-edge split flaps on tailless airplanes

Description: From Introduction: "The lift increments of different flap arrangements were determined by the method of reference 1 with a simple chord correction factor being applied. This procedure is somewhat similar in basic principles to the method of reference 2. The accuracy of the present method was determined by calculating by means of this method the lift and moment increments of flaps on 10 different finite wing-flap combinations for which wind-tunnel data were available."
Date: September 1944
Creator: Maggin, Bernard
Partner: UNT Libraries Government Documents Department

Analysis of an induction blowdown supersonic tunnel

Description: From Introduction: "In the present paper, general ejector equations (see reference 4 or 5) and certain assumptions with regard to flow conditions and pressure losses have been utilized to calculate the running times of induction blowdown supersonic tunnels operating in the mentioned Mach number range."
Date: April 1950
Creator: Bidwell, Jerold M.
Partner: UNT Libraries Government Documents Department

The 5- by 7-meter wind tunnel of the DVL

Description: The report contains a description of the DVL wind tunnel. According to the cones fixed, an elliptical stream with axes 5 by 7 meters and length 9 meters, or a stream 6 by 8 meters in cross section and 11 meters in length is available. The top speed with the smaller cone is 65 meters per second. The testing equipment consists of an automatic six-component balance and a test rig for propellers and engines up to 650 horsepower.
Date: March 1936
Creator: Kramer, M.
Partner: UNT Libraries Government Documents Department

The 6-foot-4-inch wind tunnel at the Washington Navy Yard

Description: Report discussing the 6-foot-4-inch wind tunnel and its auxiliary equipment has proven itself capable of continuous and reliable output of data. The real value of the tunnel will increase as experience is gained in checking the observed tunnel performance against full-scale performance. Such has been the case of the 8- by 8-foot tunnel, and for that reason the comparison in the calibration tests have been presented.
Date: August 1935
Creator: Desmond, G. L. & Mccrary, J. A.
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of a model wing having a split flap deflected downward and moved to the rear

Description: From Summary: "Tests were made on a model wing with three different sized split trailing-edged flaps, in the NACA 7 by 10 foot wind tunnel. The flaps were formed of the lower rear portion of the wing and were rotated downward about axes at their front edges. The lift, drag, and center of pressure were measured with the axis in its original position and also with it moved back in even steps to the trailing edge of the main wing, giving in effect an increase in area. The split flaps when deflected about their original axis locations gave slightly higher maximum lift coefficients than conventional trailing-edge flaps, and the lift coefficients were increased still further by moving the axes toward the rear. The highest value of C(sub L max), which was obtained with the largest flap hinged at 90 per cent of the chord from the leading edge, was 2.52 as compared with 1.27 for the basic wing."
Date: May 1932
Creator: Weick, Fred E. & Harris, Thomas E.
Partner: UNT Libraries Government Documents Department

Altitude investigation of XJ34-WE-32 engine performance without electronic control

Description: From Introduction: "As a part of the comprehensive investigation of the XJ34-WE-32 engine conducted in the NACA Lewis altitude wind tunnel, the over-all-performance was determined over a range of altitudes and flight Mach numbers. Other phases of the investigation are reported in reference 1. The results are given in tables and also in graphical form to show the trends of engine performance associated with changes of altitude, flight Mach number, and exhaust-nozzle area."
Date: May 29, 1953
Creator: Bloomer, Harry E.; Walker, William J. & Pantages, George L.
Partner: UNT Libraries Government Documents Department

Analysis of wind-tunnel stability and control tests in terms of flying qualities of full-scale airplanes

Description: From Introduction: "The purpose of this paper is to outline a suggested form of presentation of the results of a stability and control investigation in terms of flying qualities as defined in reference 1 and to systematize and review briefly the analytical work required for this type of presentation. No effort is made to specify definite test procedures."
Date: April 1, 1943
Creator: Kayten, Gerald G.
Partner: UNT Libraries Government Documents Department

Analysis and comparison with theory of flow-field measurements near a lifting rotor in the Langley full-scale tunnel

Description: From Introduction: "The time-averaged flows are considerably simpler to deal with theoretically than are the instantaneous flows, and the results of several theoretical analyses are available (refs. 2 to 6, for example). Several previous experimental investigations (see ref. 7 for a bibliography) have provided some qualitative information on the subject by the use of smoke in flight and in wind tunnels. However, quantitative measurements (refs. 8 to 10) are extremely scarce and, in general, are inadequate either to define the nature of the flow or to check the accuracy of the theoretical calculations."
Date: April 1956
Creator: Heyson, Harry H.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics at subsonic and supersonic Mach numbers of a thin triangular wing of aspect ratio 2 1: maximum thickness at 20 percent of the chord

Description: From Summary: "This report presents the results of a wind-tunnel investigation conducted to determine the effects of Mach number on the aerodynamic characteristics of a wing of triangular plan form."
Date: November 19, 1948
Creator: Berggren, Robert E. & Summers, James L.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a large number of airfoils tested in the variable-density wind tunnel

Description: From Summary: "The aerodynamic characteristics of a large number of miscellaneous airfoils tested in the variable-density tunnel have been reduced to a comparable form and are published in this report for convenient reference. Plots of the standard characteristics are given in tabular form. Included is a tabulation of important characteristics for the related airfoils reported in NACA report 460. This report, in conjunction with NACA report 610, makes available in comparable and convenient form the aerodynamic data for airfoils tested in the variable-density tunnel since January 1, 1931."
Date: 1938
Creator: Pinkerton, Robert M. & Greenberg, Harry
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics including pressure distribution of a fuselage and three combinations of the fuselage with swept-back wings at high subsonic speeds

Description: From Introduction: "The wings were tested in combination with fuselage similar to the one used in the 7- by 10-foot wind-tunnel investigations. The results are reported herein and are compared with results for three similar model wings on the transonic bump (references 1, 2, and 3)."
Date: February 6, 1951
Creator: Sutton, Fred B. & Martin, Andrew
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics throughout the subsonic speed range of a thin, sharp-edged horizontal tail of aspect ratio 4 equipped with a constant-chord elevator

Description: From Introduction: "Recent investigations have indicated several wing plan forms, wing sections, and wing-body-tail combinations suitable for flight at supersonic speeds. One such lifting surface, a thin, sharp-edged without sweep of aspect ratio 4 and taper ratio 0.5, has been the subject of an investigation in the Ames 12-foot pressure wind tunnel. The aim of the investigation was to determine the aerodynamic characteristics of such a wing plan form throughout the range of subsonic Mach numbers up to 0.94."
Date: June 30, 1949
Creator: Bandettini, Angelo & Reed, Verlin D.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics at subcritical and supercritical Mach numbers of two airfoil sections having sharp leading edges and extreme rearward positions of maximum thickness

Description: From Introduction: "A 12-percent-chord-thick wedge section and a reversed NACA 0012 section were chosen for these tests as they are representative of sections having no boat tailing and appreciable boat tailing (i.e., blunt and rounded trailing edges, respectively), and the results of this investigation are compared with those obtained from a previous investigation of the NACA 0012 section. Conclusions are drawn regarding the relative merits of the two unconventional sections and the conventional section in transonic speed range."
Date: November 6, 1947
Creator: Eggers, A. J., Jr.
Partner: UNT Libraries Government Documents Department

Analysis of heat and compressibility effects in internal flow systems and high-speed tests of a ram-jet system

Description: Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: July 21, 1942
Creator: Becker, John V. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department

Aerodynamic and hydrodynamic characteristics of a proposed supersonic multijet water-based hydro-ski aircraft with a variable-incidence wing

Description: From Introduction: "The configuration described in this paper represents one approach to such an airplane and the results of the wind-tunnel and tank evaluations are presented. In the present investigation, the aerodynamic longitudinal characteristics over a Mach number range from 0.6 to 1.97 were obtained."
Date: October 23, 1957
Creator: Petynia, William W.; Hasson, Dennis F. & Spooner, Stanley H.
Partner: UNT Libraries Government Documents Department

The Ames 10- by 14-inch supersonic wind tunnel

Description: From Introduction: "The purpose of the present report is to describe the 10- by 14-inch supersonic wind tunnel and its operational characteristics over the nominal Mach number range from 2.7 to 6.3. Rather complete calibration data on characteristics of flow in the test section are presented and briefly discussed."
Date: January 1, 1954
Creator: Eggers, A. J. & Nothwang, George J.
Partner: UNT Libraries Government Documents Department