Effect of tunnel configuration and testing technique on cascade performance (open access)

Effect of tunnel configuration and testing technique on cascade performance

"An investigation has been conducted to determine the influence of aspect ratio, boundary-layer control by means of slots and porous surfaces, Reynolds number, and tunnel end-wall condition upon the performance of airfoils in cascades. A representative compressor-blade section (the NACA 65-(12)(10) of aspect ratios of 1, 2, and 4 has been tested at low speeds in cascades with solid and with porous side walls. Two-dimensional flow was established in porous-wall cascades of each of the three aspect ratios tested; the flow was not two-dimensional in any of the solid-wall cascades" (p. 263).
Date: November 30, 1949
Creator: Erwin, John R. & Emery, James C.
System: The UNT Digital Library
Flight Investigations at High-Subsonic, Transonic, and Supersonic Speeds to Determine Zero-Lift Drag of Fin-Stabilized Bodies of Revolution having Fineness Ratios of 12.5, 8.91, and 6.04 and Varying Positions of Maximum Diameter (open access)

Flight Investigations at High-Subsonic, Transonic, and Supersonic Speeds to Determine Zero-Lift Drag of Fin-Stabilized Bodies of Revolution having Fineness Ratios of 12.5, 8.91, and 6.04 and Varying Positions of Maximum Diameter

Rocket-powered models were flown at high-subsonic, transonic, and supersonic speeds to determine the zero-lift drag of fin-stabilized parabolic bodies of revolution differing in fineness ratio and in position of maximum diameter. The present paper presents the results for fineness ratio 12.5, 8.91 and 6.04 bodies having maximum diameters located at stations of 20, 40, 60, and 80 percent of body length. All configurations had cut-off sterns and all had equal base, frontal, and exposed fin areas. For most of the supersonic-speed range models having their maximum diameters at the 60-percent station gave the lowest values of drag coefficient. At supersonic speeds, increasing the fineness ratio generally reduced the drag coefficient for a given position of maximum diameter.
Date: November 30, 1949
Creator: Hart, Roger G. & Katz, Ellis R.
System: The UNT Digital Library
Spin-Tunnel Investigation of the Jettisoning of External Fuel Tanks in Spins (open access)

Spin-Tunnel Investigation of the Jettisoning of External Fuel Tanks in Spins

"A spin-tunnel investigation has been made to determine the probability of external fuel tanks striking an airplane after being jettisoned in a spin. The investigation showed that for straight-wing fighter-type designs in any case in which jettisoning of tanks in a spin might aid spin recovery the tanks would probably clear all parts of the airplane" (p. 1).
Date: November 30, 1949
Creator: Berman, Theodore
System: The UNT Digital Library
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 (open access)

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

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.
System: The UNT Digital Library
Investigations at supersonic speeds of 22 triangular wings representing two airfoil sections for each of 11 apex angles (open access)

Investigations at supersonic speeds of 22 triangular wings representing two airfoil sections for each of 11 apex angles

The results of tests of 22 triangular wings, representing two leading-edge shapes for each of 11 apex angles, at Mach numbers 1.62, 1.92, and 1.40 are presented and compared with theory. All wings have a common thickness ratio of 8 percent and a common maximum-thickness point at 18 percent chord. Lift, drag, and pitching moment are given for all wings at each Mach number. The relation of transition in the boundary layer, shocks on the wing surfaces, and characteristics of the pressure distributions is discussed for several wings.
Date: March 30, 1949
Creator: Love, Eugene S.
System: The UNT Digital Library
Performance of Axial-Flow Supersonic Compressor on XJ-55-FF-1 Turbojet Engine 1: Preliminary Performance of Compressor (open access)

Performance of Axial-Flow Supersonic Compressor on XJ-55-FF-1 Turbojet Engine 1: Preliminary Performance of Compressor

An investigation was conducted to determine the performance characteristics of the axial-flow supersonic compressor of the XJ-55-FF-1 turbo Jet engine. The test unit consisted of a row of inlet guide vanes and a supersonic rotor; the stator vanes after the rotor were omitted. The maximum pressure ratio produced in the single stage was 2.28 at an equivalent tip speed or 1814 feet per second with an adiabatic efficiency of approximately 0.61, equivalent weight flow of 13.4 pounds per second. The maximum efficiency of 0.79 was obtained at an equivalent tip speed of 801 feet per second.
Date: January 30, 1949
Creator: Hartmann, Melvin J. & Graham, Robert C.
System: The UNT Digital Library