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A Preliminary Investigation of the Performance of a Short Length Turbojet Combustor Using Vaporized Hydrocarbon Fuels

Description: Two short turbojet combustors designed for use with vaporized hydrocarbon fuels were tested in a one-quarter annular duct. The experimental combustors consisted of many small "swirl-can" combustor elements manifolded together. This design approach allowed the secondary mixing zone to be considerably reduced over that of conventional combustors. The over-all combustion lengths, for the two configurations were 13.5 and 11.0 inches, approximately one-half the length of the shortest conventional combustors. These short combustors did not provide combustion efficiencies as high as those for conventional combustors at low pressures. However, over the range of combustor-inlet total-pressures expected in aircraft capable of flight at Mach numbers of 2.5 and above, these short combustors gave very high efficiencies. A combustion efficiency of 97 percent was obtained at a combustor-inlet total-pressure of 25.0 inches of mercury absolute, reference velocity of 120 feet per second, and inlet-air total temperature of 1160 deg R. By proportioning the fuel flow between the manifold rows of can combustor elements, control of the combustor-outlet radial total-temperature profile was demonstrated. Combustor totalpressure loss varied from 0.75 percent of the inlet total pressure at isothermal conditions and a reference velocity of 75 feet per second to 5.5 percent at a total-temperature ratio of 1.8 and a reference velocity of 180 feet per second.
Date: January 7, 1958
Creator: Jones, R. E. & Pawlik, E. V.

Preliminary investigation of the performance of a single tubular combustor at pressure up to 12 atmospheres

Description: The effects of combustor operation at conditions representative of those encountered in high pressure-ratio turbojet engines or at high flight speeds on carbon deposition, exhaust smoke, and combustion efficiency were studied in a single tubular combustor. Carbon deposition and smoke formation tests were conducted over a range of combustor-inlet pressures from 33 to 173 pounds per square inch absolute and combustor reference velocities from 78 to 143 feet per second. Combustion efficiency tests were conducted over a range of pressures from 58 to 117 pounds per square inch absolute and velocities from 89 to 172 feet per second.
Date: January 28, 1954
Creator: Wear, Jerrold D & Butze, Helmut F

Preliminary Investigation of the Static Longitudinal and Lateral Stability Characteristics of a 0.05-Scale Model of the Convair F2Y-1 Airplane at High Subsonic Speeds

Description: At the request of the Bureau of Aeronautics, Department of the Navy, National Advisory Committee for Aeronautics has conducted a preliminary investigation at high subsonic speeds of the static longitudinal and lateral stability characteristics of a 0.05-scale model of the Convair F2Y-1 water-based fighter airplane. The tests covered a Mach number range from 0.5 to 0.94 and corresponding Reynolds numbers, based on the wing mean aerodynamic chord, from 3.3 x 10(exp 6) to 4.3 x 10(exp 6). The maximum angle-of-attack range (obtained at the lower Mach numbers) was from -2 degrees to 25 degrees. Sideslip angles from -4 degrees to 12 degrees also were investigated. The investigation included effects of various arrangements of wing fences and of rocket packages.
Date: January 12, 1954
Creator: Spreemann, Kenneth P. & Few, Albert G., Jr.

Preliminary investigation of the supersonic flow field downstream of wire-mesh nozzles in a constant-area duct / Lawrence I. Gould

Description: An investigation was conducted in a 3.4- by 3.4-inch duct to determine the characteristics of the supersonic flow downstream of four wire-mesh screen nozzles with nominal design Mach numbers in the range between 1.97 and 2.58. Two types of disturbances were observed in the flow field: a fine network of interacting expansion and compression waves which were formed immediately downstream of the screens and appeared to dissipate within 25 to 40 wave intersections; and relatively strong oblique shock waves that originated at the junctions of the screens and the walls and were reflected throughout the length of the duct. Regions of fairly uniform flow were found to exist. The total-pressure loss across the screens varied from 22 percent at Mach number 1.58 to 43 percent at Mach number 2.06.
Date: August 14, 1951
Creator: Gould, Lawrence I

A Preliminary Investigation of Triassic Rocks in the Lukachukai Mountains, Arizona

Description: Abstract: During the summer of 1955, two test holes were drilled into the Triassic Chinle Formation in the Lukachukai Mountains near Cove, Arizona, to obtain geologic information. Brief airborne and ground reconnaissance was made of Triassic outcrops near Cove. No anomalous radioactivity was found in the test holes, but chemical tests showed concentrations of heavy metals in conglomerate lenses in the Chinle Formation. Channel sandstones in the middle part of the Petrified Forest Member appear to be the most favorable for mineralization. The Shinarump Member, here underlain by a permeable unit, and occurring at depths greater than 500 feet, appears less promising for uranium exploration.
Date: December 3, 1956
Creator: Kosatka, Raymond F.

Preliminary investigation of use of conical flow separation for efficient supersonic diffusion

Description: Use of flow separation on a rod projecting upstream of a blunt body to decelerate the supersonic stream ahead of an annular nose inlet was investigated at Mach numbers of 1.76, 1.93, and 2.10. Maximum pressure recoveries were obtained with rod tip projections about 1.5 times the radius of the spherical nose and were higher than those obtained with single-shock solid cones. Subcritical operation was similar to that observed with solid-cone inlets, but the effect of angle of attack on maximum pressure recovery was more severe.
Date: December 17, 1951
Creator: Moeckel, W E & Evans, P J , Jr

Preliminary investigation on boundary layer control by means of suction and pressure with the U.S.A. 27 airfoil

Description: The tests described in this report constitute a preliminary investigation of airfoil boundary layer control, as carried out in the atmospheric wind tunnel of the Langley Memorial Aeronautical Laboratory, from February to August, 1927. Tests were made on a U.S.A. 27 airfoil section with various slot shapes and combinations, and at various amounts of pressure or suction on the slots. The lift of airfoils can be increased by removing or by accelerating the boundary layer. Removing the boundary layer by suction is more economical than to accelerate it by jet action. Gauze-covered suction slots apparently give the best results. When not in operation, all suction slots tested had a detrimental effect upon the aerodynamic characteristics of the airfoil which was not apparent with the backward-opening pressure slots. Thick, blunt-nose airfoils would seem to give best results with boundary layer control.
Date: May 1, 1928
Creator: Reid, E G & Bamber, M J