Download or read book Pressure Recovery in Constant Area Supersonic Diffusers written by Peter E. Merkli and published by . This book was released on 1974 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge of diffuser performance is largely based on specific configurations of a given facility, often leading to little generality. With new interest in diffuser performance, this report aims at giving a more general view of the view of the behavior of the simplest supersonic diffuser, the constant area duct. Experiments were performed in a wide range of Reynolds number, Mach number and a boundary layer parameter. No clear dependence of the pressure recovery on the Reynolds number was found in the range investigated, but charts based on the experiments and supported by a simplified model correlate the pressure recovery and the length of the recovery zone as functions of Mach number and boundary layer parameter.
Download or read book Calculation of Pressure Recovery in a Constant Area Supersonic Diffuser written by Ernst Becker and published by . This book was released on 1978 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pressure Recovery in Rectangular Adjustable Area Supersonic Diffusers written by Peter E. Merkli and published by . This book was released on 1975 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following an investigation of a simple, rectangular constant area duct supersonic diffuser, three types of variable area diffusers have been tested. Again these diffusers consisted essentially of a duct, but with two opposing pivoting elements to form a second throat smaller than the nozzle exit area. As expected, the performance of a refined diffuser can be better than that of a simple duct.
Download or read book The Flow Starting Process in Constant Area Supersonic Diffusers in a Ludwieg Tube written by Peter E. Merkli and published by . This book was released on 1976 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Ludwieg tube with a diaphragm located either upstream or downstream of the test section was used to investigate starting times of flow. For a downstream diaphragm location the starting times were found to be dependent on the diffuser length, but independent of the initial pressure ratio across nozzle and diffuser, as long as this ratio was low enough to allow supersonic flow to be established. For the upstream diaphragm location, the starting times were much shorter than those for downstream diaphragm location. In this second situation, the starting times, however, increased with the pressure ratio across the entire nozzle-diffuser section. For both upstream and downstream diaphragm locations the starting times for supersonic flow at the nozzle exit were longer for the longer diffusers. The lowest overall pressure ratio needed for the flow to start was about 1.2 times the value of the optimum operating pressure recovery ratio for steady flow. The latter ratio was found in previous experiments in a smaller continuous wind tunnel with a geometrically similar nozzle and diffuser. The required diffuser length for starting at the optimum pressure ratio corresponds to the expected recovery length of the diffuser as derived from the earlier work with steady flow.
Download or read book Supersonic Inlet Diffusers and Introduction to Internal Aerodynamics written by Rudolf Hermann and published by . This book was released on 1956 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preliminary Investigation of Supersonic Diffusers written by Arthur Kantrowitz and published by . This book was released on 1945 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summary: The deceleration of air from supersonic velocities in channels has been studied. It has become apparent that a normal shock in the diverging part of the diffuser is probably necessary for stable flow, and ways of minimizing the intensity of this shock have been developed. The effect of various geometrical parameters, especially contraction ratio in the entrance region, on the performance of supersonic diffusers has been investigated. By the use of these results, diffusers were designed which, starting without initial boundary layer, recovered 90 percent of the kinetic energy in supersonic air streams up to a Mach number of 1.85.
Download or read book Pressure Recovery and Related Properties in Supersonic Diffusers A Review written by and published by . This book was released on 1974 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report covers a literature survey on the status of present knowledge on supersonic diffusers. Three types of diffusers are examined: wind tunnel diffusers, ramjet inlets, and supersonic ejectors. No systematic study on wind tunnel diffusers has been found. The results obtained in specific studies, made in conjunction with the design and installation of a number of wind tunnels, show that 100% of normal shock recovery is obtained for M less than 10. Some systematic work exists for ramjet diffusers, with most of the attention being paid to external compression configurations. For supersonic ejectors, comprehensive studies have been made, and useful empirical design methods are available.
Download or read book Pressure Recovery Drag and Subcritical Stability Characteristics of Conical Supersonic Diffusers with Boundary layer Removal written by Leonard J. Obery and published by . This book was released on 1952 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Variation of Aspect Ratio on the Pressure Recovery in Super Sonic Diffusers written by and published by . This book was released on 1979 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: A systematic investigation was made of the gasdynamics of supersonic diffusers, in particular, diffusers applicable to gasdynamic or other types of flow lasers. The main conclusion was that almost all the research on supersonic diffusers was performed with specific application, namely a specific wind tunnel installation or an engine, in mind. Systematic studies on the gasdynamics of diffusers even of simple geometries were scarce, making it difficult, if not impossible, to extend existing work to other configurations. Despite the fact that some of the high Mach number wind tunnels operated with known unequilibrated internal modes, there was no research on nonequilibrium flow effects in diffusers in the literature consulted. Moreover, in most conventional wind tunnels, the cross-section of the test section is either circular or squarish. Consequently, most diffuser studies were concerned with circular, square, or rectangular cross-sections with comparable widths and heights, characterized by an aspect ratio, defined as the width to height ratio, of unity or close to unity.
Download or read book A Study of Pressure Recovery with Liquid Injection in a Supersonic Diffuser written by Hugh Elvin Youngblood and published by . This book was released on 1968 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design Point Pressure Recovery of a Highly Maneuverable Target Aircraft written by Kenneth W. Lee and published by . This book was released on 1973 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pressure Recovery in a Constant Area Diffuser for Chemical Lasers with Nozzle Base Relief written by D. A. Durran and published by . This book was released on 1975 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of pressure recovery in a supersonic flow in which energetic exothermic reactions occur has been performed that is applicable for a cw chemical laser. Analytical and experimental work has shown that typical HF(DF) laser flows can be recovered to approximately 200 Torr with the use of a constant-area diffuser. In addition, base relief, i.e., 'deadwater' regions, in the laser nozzle can be used to facilitate constant-pressure operation in the laser cavity without significantly reducing the potential for pressure recovery in the diffuser.
Download or read book Preliminary Attempts at Isothermal Compression of a Supersonic Air Stream written by E. Perchonok and published by . This book was released on 1956 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Guided by analytical predictions, preliminary experiments were undertaken in an attempt to achieve isothermal (constant static temperature) compression of a supersonic air stream. Application of the process to a supersonic inlet diffuser at free-stream Mach numbers of 1.9 and 3.0 did not produce the theoretically predicted total-pressure rise. Large total-pressure losses due to momentum exchange between the inlet air stream and the coolant occurred, as expected, but the compensating rise in pressure theoretically associated with the available evaporation cooling was not observed. Tests at a Mach number of 3.0 with a heated air stream and multipoint upstream injection suggest that some gain in diffuser pressure recovery might be obtained with a full-scale inlet at the high stagnation temperature of supersonic flight.
Download or read book The Use of Perforated Inlets for Efficient Supersonic Diffusion written by John C. Evvard and published by . This book was released on 1951 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Diffuser Research written by Peter P. Wegener and published by . This book was released on 1977 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research concerned a survey of existing literature on supersonic diffusers, and experimental study on pressure recovery of supersonic diffusers in a variety of facilities with a variety of configurations following a contoured Mach Number = 3 nozzle. The nozzle and test section were free of models and the diffusers were either of constant cross section (straight duct), or of variable cross section, and they were generally patterned to be representative of some classes of gasdynamic laser nozzles. The optimum pressure recovery of the operating facility and the minimum pressure recovery required to start supersonic flow at the nozzle end were determined. The facilities used were a small continuous operation supersonic wind tunnel and a Ludwieg tube operating as a blow down wind tunnel with a steady state in the millisecond region. Careful correlation with data from other facilities taken under different circumstances was performed, while a number of the results found were unique to the current investigation.
Download or read book Report written by United States. National Advisory Committee for Aeronautics and published by . This book was released on 1957 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Supersonic Aerodynamics written by George Rudinger and published by . This book was released on 1964 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:
