The report summarizes source material on combustion for flight-propulsion engineers. First, several chapters review fundamental processes such as fuel-air mixture preparation, gas flow and mixing, flammability and ignition, flame propagation in both homogenous and heterogenous media, flame stabilization, combustion oscillations, and smoke and carbon formation. The practical significance and the relation of these processes to theory are presented. A second series of chapters describes the observed performance and design problems of engine combustors of the principal types. An attempt is made to interpret performance in terms of the fundamental processes and theories previously reviewed. Third, the design of high-speed combustion systems is discussed. Combustor design principles that can be established from basic considerations and from experience with actual combustors are described. Finally, future requirements for aircraft engine combustion systems are examined.
Report discussing an aerodynamic control effectiveness study using free-flight, rocket-propelled test vehicles. Information about the effects of wing sweepback, aspect ratio, taper ratio, and section thickness ratio on the rolling effectiveness of full-span, sealed ailerons is provided.
This report includes the description and results of an experiment evaluating the amount of adhesion existing between the liquid boron oxide and various materials used in engines.
Report presenting an investigation in the 16-foot transonic tunnel to determine the effects of leading-edge slats on the aerodynamic and longitudinal stability characteristics of a model of a swept-wing fighter-type airplane. Two different spanwise extents of leading-edge slats were tested, from 35 to 95 percent semispan and from 46 to 95 percent semispan. Results regarding the lift characteristics, drag characteristics and lift-drag ratios, stability characteristics, and flow-study pictures are provided.
"Tests have been conducted in the Langley 8-foot transonic tunnel on a 0.04956-scale model of the Convair F-102A airplane which employed an indented and extended fuselage, cambered wing leading edges, and deflected wing tips. Force and moment characteristics were obtained for Mach numbers from 0.60 to 1.135 at angles of attack up to 20 degrees. In addition, tests were made over a limited angle-of-attack range to determine the effects of the cambered leading edges, deflected tips, and a nose section with a smooth area distribution" (p. 1).
From Introduction: "Numerous tests of tip controls on delta wings at transonic and low supersonic speeds have shown that such configurations provide satisfactory rolling-moment effectiveness, and that the hinge can be controlled by proper location of the hinge line (ref. 1). The purpose of the present tests is to determine the characteristics of such a configuration at Mach number of 4.04 and a Reynolds number of 5.8 X 10^6, based on the wing mean aerodynamic chord."
Report presenting an investigation to determine the aerodynamic characteristics of a cruciform 70 degree delta-wing missile configuration with 70 degree delta canard control surfaces at M = 1.41 in the 4- by 4-foot supersonic pressure tunnel. Modifications to the configuration included variation of the body length and canard area and the substitution of a series of very small span wings for the cruciform delta wings and canard controls.
"A summary and analysis have been made of the results of various investigations to determine the aerodynamic characteristics of a supersonic aircraft configuration. The configuration has a wing with 40 degree sweepback at the quarter-chord line, aspect ratio 4, taper ratio 0.5, and 10-percent-thick circular-arc sections normal to the quarter-chord line. Experimental data were available for a Mach number range from 0.16 to 2.32. Results obtained from wing-flow, rocket-model, transonic-bump, and tunnel tests are presented and, where possible, are supplemented by empirical and theoretical calculations" (p. 1).
From Introduction: "This paper presents the results of the investigation of wing-alone and wing-fuselage combinations employing a wing with the quarter-chord line swept back 35^o, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section."
From Introduction: "This report presents the results of an investigation in the NACA Lewis 1- by 1-foot supersonic wind tunnel of two flat-bottomed bodies to determine their aerodynamic characteristics at a Mach number of 3.12."
From Summary: "The effects of externally mounted rockets and fuel tanks on the aerodynamic characteristics of an airplane model with a swept-back wing are presented in this report."
Report presenting an investigation to determine separately the aerodynamic characteristics of a Douglas Aircraft Company store and a semispan delta-wing-fuselage configuration in the presence of one another. The store was located at the 50-percent-semispan station with the store nose both ahead of and behind the wing leading edge for two longitudinal and three vertical positions.
Report presenting an experimental investigation to determine the aerodynamic characteristics of a slender cone-cylinder body of revolution in the 1- by 1-foot supersonic wind tunnel. Viscous drag and three component forces were measured at Mach number 3.12 and a range of Reynolds numbers and angles of attack. Results regarding pressure distributions, boundary layer, and forces are provided.
Report presenting an investigation of the aerodynamic interference effects associated with a missile configuration, consisting of a pointed body of revolution with one or two ramjet engines strut-mounted in a vertical plane through the center line of the body, at several engine locations relative to the body and a range of angles of attack. The experimental data indicated increases in slope of the normal force curve with outward movement of the engines. Results regarding the characteristics of isolated components, characteristics of representative configurations, interference effects, and effect of engine location on lift-drag ratio are provided.
Report presenting the air-flow behavior over the wing of an XP-51 airplane including photographs of tufts attached to the wing surface and chordwise pressure distributions. A comparison of tuft studies from flight results are compared with results from wind-tunnel testing. Three types of flow were observed: steady flow, unsteady flow, and break-away flow are provided.
"The XF-12 airplane was designed by Republic Aviation Corporation to provide the Army Air Forces with a high performance, photo reconnaissance aircraft. A series of air-stream surveys were made n the vicinity of the empennage of a 1/8.33-scale powered model of the XF-12 airplane in the Langley 19-foot pressure tunnel. Surveys of the vortical-tail region were made through a range of yaw angles of plus or minus 20 degrees at a high and low angle of attack" (p. 1).
From Introduction: "The investigation reported herein was therefore undertaken to extend this study to altitude conditions in which the low fuel-flow rates occur over the full range of engine speeds."
An investigation of tail-pipe burning was conducted in the NACA Lewis altitude wind tunnel with a full-scale turbojet engine and an 29-inch-diameter tail-pipe burner. Effects of fuel distribution and number and arrangement of stages on performance and operational characteristics of several fuel-cooled flame holders are presented and discussed. Operation with a three-stage flame holder having the large stage upstream was the most efficient. Combustion efficiency was slightly increased at high altitudes by injecting fuel upstream of the flame holder.
Report discussing three fuels conforming to AN-F-58 specification were investigated in order to determine the influence of boiling temperatures and aromatic content on altitude performance in single combustor of a 4600-pound-thrust turbojet engine.
From Introduction: "Experimental investigations of the combustion characteristics of diborane, pentaborane, and pentaborane-hydrocarbon blends in modified turbojet combustors have been conducted at this laboratory at the request of the Bureau of Aeronautics, Department of the Navy, as part of Project Zip. Results of these single-combustor tests are presented in references 2 to 5."
"Ignition of the fuel-air mixture in an afterburner of turbojet engine at altitude has often proved to be a different problem to solve. Electrical ignition has not proven satisfactory because of the unreliability of such systems (ref. 1). The ignition data reported herein were obtained for two after-burner configurations. Autoignition data are included for both configurations and hot-streak-ignition data, for only one. "
"Investigations were conducted in the Cleveland altitude wind tunnel to determine the performance and operational characteristics of the 19B-2, 19B-8, and 19XS-1 turbojet engines. One objective was to determine the effect of altitude, flight Mach number, and tail-pipe-nozzle area on the performance characteristics of the six-stage and ten-stage axial-flow compressors of the 19B-8 and 19XB-1 engines, respectively, The data were obtained over a range of simulated altitudes and flight Mach numbers" (p. 1).
The performance characteristics of the 19B-8 and 19XB-1 turbojet engines and the windmilling-drag characteristics of the 19B-6 engine were determined in the Cleveland altitude wind tunnel. The investigations were conducted on the 19B-8 engine at simulated altitudes from 5000 to 25,000 feet with various free-stream ram-pressure ratios and on the 19XB--1 engine at simulated altitudes from 5000 to 30,000 feet with approximately static free-stream conditions.
From Introduction: "Because of the unusual nature of this equipment, and because it is proving to be very useful for certain kinds of aerodynamic research, this report has been prepared. It contains a description of the equipment and its use to obtain aerodynamic coefficients. The imperfections in the wind-tunnel air stream and their effect on model tests are also discussed."
Memorandum presenting a description of the Ames supersonic free-flight wind tunnel, which is a new piece of equipment for aerodynamic research at high supersonic Mach numbers. It has a wide Mach number range extending from low supersonic speeds to Mach numbers in excess of 10. The air stream in the tunnel is imperfect, mainly due to a symmetrical pair of oblique shock waves which reflect down the test section.
From Introduction: "In this study wide variations in many of the pertinent aerodynamic were investigated at subsonic and supersonic speeds. The effects of large changes in principal axis inclination and mass distribution are also included. The primary purpose of this paper is to summarize the information obtained from the analog calculations and to compare the results with the trends predicted from a slightly modified version of reference 2."
This report presents an analysis of a compound engine operating with manifold pressures ranging from 60 to 110 lb/sq in. absolute and discusses the effects of engine limits (peak cylinder pressure and turbine-inlet temperature) and component efficiency.
Report presenting analytical estimates of the thrust, efficiency, drag, and weight of the air-turborocket engine. The effects of changes in the engine components on design and off-design performance are emphasized. Results regarding the performance, effect of design parameters, effect of subsonic cruising Mach number, geometry variations, engine weight estimates, and comparison with turbojet engines are provided.
From Introduction: "The use of automatic controls to reduce the tendency for rolling divergence has been investigated in references 2 and 3. These studies have considered the effect of artificial changes in certain stability derivatives on the rolling divergence, and have shown that increased damping in pitch may be quite effective in reducing the divergent tendency. In the present report, a different type of automatic control is investigated."
From Introduction: "The purpose of the present paper is to summarize the available data on the effects of wing-fuselage-tail and wing-nacelle interference on the distribution of the air load among aircraft components. Some discussion is also given of the effects of center-of-gravity position."
From Introduction: "This report presents the cooling-air requirements of a "paper" air-cooled turbojet engine operating over a wide range of flight Mach numbers and altitudes. The results are presented for a two-stage-turbine turbo-jet engine having a turbine-inlet temperature of 2500^o R and operating at sea-level static conditions and flight Mach numbers from 0.90 to 2.5 and flight altitudes from 40,000 to 70,000 feet. In addition, the effect of decreasing the blade-inlet cooling-air temperature on the required coolant-flow ratio is presented."
Memorandum presenting an investigation of the steady-state wing loads conducted on a Boeing B-52 airplane over a range of Mach numbers and altitudes. Results regarding flight tests and air-load calculations are provided.
From Introduction: "This paper presents the results obtained during the phase of the B-52 flight investigation concerned with the steady-state wing loads. Where possible, the effects of Mach number and flexibility on the measured load are analyzed and presented."
From Summary: "Calculated velocity and temperature distributions, as well as relations among Nusselt number, Reynolds number, and friction factor, are presented. The effect of variation of fluid properties across the tube on the Nusselt number and friction factor correlations can be eliminated by evaluating the properties at a reference temperature which is a function of both the wall temperature and the ratio of wall-to-bulk temperatures."
The following report covers an investigation that was done to supplement available experimental data on flow fields behind wings of an aircraft at supersonic speeds, as well as to furnish more quantitative information on the choice of the theoretical method for a given configuration and the accuracy to be expected when using such a method.
Report presenting the wing-section pressure-distribution and wing-panel load characteristics of the Douglas D-558-II airplane for a range of Mach numbers and airplane normal-force coefficients. At subsonic speeds, the pressure distributions are characterized by a high negative-pressure peak with an abrupt pressure recovery as a result of the leading-edge expansion over the upper surface at moderate angles of attack.
Report presenting an investigation of the effects of various mass, aerodynamic, and dimensional parameters on the dynamic lateral stability of the Douglas D-558-2 airplane. Results regarding an airplane with the flaps and gear retracted, airplane at sea level with flaps deflected 50 degrees and landing gear lowered, and effect of assumed modifications to airplane are provided.
From Introduction: "The investigation is discussed in the present report is an analysis of the turbojet engine as the power plant for bombers capable of supersonic flight speeds. A similar analysis, in which the turbojet engine is considered for the propulsion of supersonic fighter aircraft, is presented in reference 1. Two plans are considered in this report."
Report presenting an investigation of thrust augmentation by injection of water and water-alcohol mixtures in the combustion chambers at sea-level zero-ram flight conditions on 4000-pound-thrust axial-flow and centrifugal-flow turbojet engines. Thrust augmentation, compressor characteristics, fuel flow, and turbine-outlet-temperature distributions are presented for various injection rates and water-alcohol mixtures.
From Summary: "Procedures for applying these analytical methods to experimentally measured blade-metal temperatures are presented. Data are presented for the leading and trailing edge of a symmetrical water-cooled blade to illustrate the validity of the methods for those portions of the blade. In addition to the application to turbine blades, the methods can be applied to any heat-transfer apparatus having a profile that can be approximated by the shape discussed."
Memorandum presenting the effects of wing modification and stability augmentation on the computed longitudinal behavior in the pitch-up region and probable pilot opinion of the pitch-up characteristics of two current fighter airplanes. An exploration of the addition of a wing-leading edge is included. Results regarding computed pitch-up behavior and probable pilot opinion are provided.
From Introduction: "Analyses that provide a basis for comparing the centrifugal-stress distributions inherent in jet-engine turbine blades of several designs currently in use were therefore made and are presented."
From Introduction: "The purpose of this report is to further analyze the turbine performance results of reference 1 with the objective of isolating the contribution of the cooling air to the turbine performance and establishing some systematic relation between these cooling-air effects and the turbine operational parameters."
Memorandum presenting a theoretical investigation to determine the reasons for poor airplane response to longitudinal control. Some effects of airplane configuration on the response, primarily for short time periods, were also determined. Results regarding a comparison of three airplanes, the effect of changes on airplane B, and the effect of changes on airplane C are provided.
From Introduction: "A theoretical investigation was conducted in order to determine what effect the differences in aerodynamic characteristics would have on the short-time response to elevator control of this type of airplane as compared with the responses of a conventional airplane, without regard to any possible psychological influences. The results of this investigation are presented in this paper."
Report presenting the combustion efficiencies of 10 experimental jet-propulsion fuels that are approximately 200 degrees Fahrenheit cuts of five selected crudes available in large quantities in a turbojet engine combustor at altitude conditions.
Report presenting an investigation of the validity of application of the simplified-radial-equilibrium equation to axial-flow turbomachines. Two different types of equations were used. Results regarding the interpretation of the data, single stages, middle and end stages of the multistage compressor, application of the radial-equilibrium equation, and the solution for the velocity distributions are provided.
From Introduction: "The purpose of this paper is to present an analytical method for the design of two-dimensional related selection of a blade for particular rotor conditions may be made quickly and easily and its performance deduced from tests of representative sections in cascade."
Report presenting a simple geometric relation that allows the effect of geometric dihedral on the rolling moment due to sideslip at transonic and supersonic speeds to be estimated if the damping in roll or rolling moment due to differential wing incidence is known. There is no experimental information available to check certain equations, but the approximations look promising at this time.
An analysis has been made of available experimental data to show the effects of most variables that are predominant in determining base pressure at supersonic speeds. Two dimensional bases and bases of bodies of revolution, restricted to turbulent boundary layers, are covered.
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