Download or read book High Resolution Measurements of Supersonic Shear Flow Mixing and Combustion written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation of compressibility effects on the large-scale structure scaling laws, and entrainment and mixing rates in supersonic, planar, turbulent, bluff-body wakes was conducted. The compressibility effects in supersonic wakes were found to differ significantly from those in supersonic mixing layers. Results at free stream Mach numbers 2 and 3 showed that the large-scale structure of incompressible turbulent wakes was recovered in supersonic wakes at downstream locations where the local Mach number became sufficiently small. No organized large-scale structure was found where the local Mach number was greater than O.7. Unlike supersonic mixing layers, the results showed that the principal effect of compressibility in supersonic wakes was a local self-induced forcing, where reflected expansion waves from the near-field recompression region intersected the wake.
Download or read book High Resolution Measurements of Supersonic Mixing and Combustion in Coflowing Turbulent Jets written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study of compressibility effects on the large scale structure and outer variable scaling laws of a coflowing turbulent jet was partially completed. Results showed distinct large scale structure and classical incompressible scaling where the convective Mach number has decreased to subsonic values. At supersonic convective Mach numbers no large scale structure was seen and incompressible scalings were dramatically modified. Experiments also showed strong effects due to oblique shock wave interactions with combustion in supersonic turbulent jets. OH PLIF imaging measurements comparing subsonic and supersonic jets documented striking differences in their mixing and combustion properties. Combined OH/CH PLIF imaging measurements found large differences in the combustion properties of jet flames created by small differences in the fuel injection design. A theoretical study of density effects due to combustion heat release on the outer variable scalings of turbulent shear flows was completed. This study produced a general methodology for predicting the changes in such quantities as growth rates, velocity decay, and entrainment and mixing rates due to heat release. Comparisons with measured heat release effects in the literature, including planar and axisymmetric jet flames as well as mixing layers, showed excellent agreement with this general approach.
Download or read book Support for Graduate Research in Supersonic Reacting Flows written by Mark Godfrey Mungal and published by . This book was released on 1998 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work was aimed at obtaining a more fundamental understanding of mixing and combustion in supersonic flows. Advanced laser based techniques for measurements in an existing supersonic shear layer facility were primarily used. The main scientific question addressed was a comparison of the similarities and differences between mixing and reaction when compressibility plays a significant role. To this end, Particle Image Velocimetry (PIV) was used to obtain detailed, whole field velocity measurements under a range of compressibility conditions. These measurements are complementary to earlier measurements of scalar concentrations in similar flows. New observations concerning the nature of the instantaneous velocity and vorticity fields were made as a function of compressibility. In addition, Planar Laser Mie Scattering is used to obtain structure velocity measurements for comparison with the actual fluid velocities.
Download or read book Turbulent Shear Layers in Supersonic Flow written by Alexander J. Smits and published by Springer Science & Business Media. This book was released on 2006-05-11 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: A good understanding of turbulent compressible flows is essential to the design and operation of high-speed vehicles. Such flows occur, for example, in the external flow over the surfaces of supersonic aircraft, and in the internal flow through the engines. Our ability to predict the aerodynamic lift, drag, propulsion and maneuverability of high-speed vehicles is crucially dependent on our knowledge of turbulent shear layers, and our understanding of their behavior in the presence of shock waves and regions of changing pressure. Turbulent Shear Layers in Supersonic Flow provides a comprehensive introduction to the field, and helps provide a basis for future work in this area. Wherever possible we use the available experimental work, and the results from numerical simulations to illustrate and develop a physical understanding of turbulent compressible flows.
Download or read book ARO and AFOSR Contractors Meeting in Chemical Propulsion Held in Virginia Beach Virginia on 3 6 June 1996 written by David M. Mann and published by . This book was released on 1996 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Partial contents: Supercritical droplet behavior; Fundamentals of acoustic instabilities in liquid-propellant rockets; Modeling liquid jet atomization proceses; Liquid-propellant droplets dynamics and combustions in supercritical forced convective environments; Contributions of shear coaxial injectors to liquid rocket motor combustion instabilities; High pressure combustion studies under combustion driven oscillatory flow conditions; Droplet collision on liquid propellant combustion; Combustion and plumes; Development of a collisional radiative emission model for strongly nonequilibrium flows; Energy transfer processes in the production of excited states in reacting rocket flows; modeling nonequilibrium radiation in high altitude plumes; kinetics of plume radiation, and of HEDMs and metallic fuels combustion; Nonsteady combustion mechanisms of advanced solid propellants; Chemical mechanisms at the burning surface. p15
Download or read book Combustion Related Shear Flow Dynamics in Elliptic Supersonic Jets written by K. C. Schadow and published by . This book was released on 1987 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: An elliptic jet having an aspect ratio of 3:1 was studied and compared to a circular jet at three Mach numbers: M = 0.15, 1 and 1.3. Hot-wire measurements and Schlieren photography were employed in this study. The superior mixing characteristics of an elliptic jet relative to a circular jet, which were found in previous works in subsonic jets, prevail in the sonic jet and are further augmented by the shock structures of the supersonic underexpanded jet. The major and minor axes switch at a distance of 3 diameters from the nozzle, and the spreading rate of the minor axis side is twice that of a subsonic jet. The experimental data are supported by results of the linear instability analysis of the supersonic elliptic jet which show that the initial vortices are bending at the major axis side in a similar way to the process which occurs in a subsonic elliptic jet.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Speed Reacting Flows Research to Understand Processes in Supersonic Combustors written by H. Krier and published by . This book was released on 1987 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this program is to determine the fundamental fluid dynamic mechanisms occurring in the mixing and entrainment processes in the free shear layer formed between two high-speed (supersonic/sonic) streams. How the fluid mixing and subsequent combustion depends upon compressibility, as well as other parameters of the free shear layer process, is currently being investigated in an experimental study of the two-dimensional, compressible, turbulent reactive free shear layer. Use of non-intrusive, laser-based diagnostics including laser Schlieren for flow visualization, Laser Doppler Velocimetry (LDV) for velocity and turbulence measurement, and Planar Laser-Induced Fluorescence (PLIF) for temperature and concentration measurements are being employed.
Download or read book Some Optical Techniques for Temperature and Concentration Measurements of Combustion in Supersonic Streams written by Erwin A. Lezberg and published by . This book was released on 1964 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unsteady Supersonic Combustion written by Mingbo Sun and published by Springer Nature. This book was released on 2020-04-14 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the unsteady phenomena needed to understand supersonic combustion. Following an initial chapter that introduces readers to the basic concepts in and classical studies on unsteady supersonic combustion, the book highlights recent studies on unsteady phenomena, which offer insights on e.g. interactions between acoustic waves and flames, flow dominating instability, ignition instability, flame flashback, and near-blowout-limit combustion. In turn, the book discusses in detail the fundamental mechanisms of these phenomena, and puts forward practical suggestions for future scramjet design.
Download or read book Basic Instability Mechanisms in Chemically Reacting Subsonic and Supersonic Flows written by Tau-Yi Toong and published by . This book was released on 1989 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Flow Mixing and Combustion Using Ramp Nozzle written by K. Yu and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1994 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 28th AIAA Fluid Dynamics Conference 4th AIAA Shear Flow Control Conference written by and published by . This book was released on 1997 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mixing Chemical Reactions and Combustion in Subsonic and Supersonic Turbulent Flows written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work completed, or in progress, by the end of the first grant year includes a study of the effects of initial conditions on high Reynolds number shear layers, where it was shown that they also influence molecular mixing far downstream of the splitter plate; moderate Reynolds number, liquid-phase transverse jets in a cross flow, including their three-dimensional structure; the discovery of a power-law similarity in the surface-to root-area ratio of scalar structures in liquid-phase turbulent jets; numerical investigations of hydrocarbon ignition and the effects of additives in a high-strain rate environment, as would be encountered in air-breathing scramjet propulsion; and further advances and applications of velocity-field measurements from image sequences of convected scalars.
Download or read book Aeronautical Engineering written by and published by . This book was released on 1993 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
