Download or read book The Effects of Compressibility on a Supersonic Mixing Layer written by D. Nixon and published by . This book was released on 1989 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the work is to identify the flow mechanism that cause the decrease in spreading rate of supersonic mixing layers as the convective Mach number increases and to suggest means of enhancing the mixing. Two approaches have been taken, one numerical and one analytic. A computer code, TMRC, has been used to simulate both time and space developing mixing layers to get some indication of the flow physics. To complement the numerical study a simple analysis has been developed which explains the variation of mixing rate with convective Mach number. The analysis seems to indicate that little can be done to Mach number. The analysis seems to indicate that little can be done to enhance mixing as such although the real problem of simultaneous mixing and combustion may be more amendable to control. Keywords: Mixing layers; Compressible flow; Fluid dynamics; Airflow. (KT).
Download or read book The Effects of Compressibility on a Supersonic Mixing Layer written by D. Nixon and published by . This book was released on 1991 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the work is to identify the flow mechanisms that cause the decrease in spreading rate of supersonic mixing layers as the convective Mach number increases and to suggest means of enhancing the mixing. Two approaches have been taken, one numerical and one analytic. A computer code, TMRC, has been used to simulate both time and space developing two-dimensional mixing layers to get some indication of the flow physics. In addition, three-dimensional spatially developing mixing layers have been simulated. The numerical studies indicate that some accuracy problems may exist in existing algorithms. To complement the numerical study a simple analysis has been developed which explains the variation of mixing rate with convective Mach number. The analysis seems to indicate that little can be done to enhance mixing as such, although the real problem of simultaneous mixing and combustion may be more amenable to control. The analysis has been extended to include heat release as a first step in this direction.
Download or read book Compressibility Effect on the Supersonic Reacting Mixing Layer written by O. H. Planche and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Compressibility Effects on Fluid Entrainment by Turbulent Mixing Layers written by Jacques A. F. Hill and published by . This book was released on 1964 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compressibility Turbulence and High Speed Flow written by Thomas B. Gatski and published by Academic Press. This book was released on 2013-03-05 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compressibility, Turbulence and High Speed Flow introduces the reader to the field of compressible turbulence and compressible turbulent flows across a broad speed range, through a unique complimentary treatment of both the theoretical foundations and the measurement and analysis tools currently used. The book provides the reader with the necessary background and current trends in the theoretical and experimental aspects of compressible turbulent flows and compressible turbulence. Detailed derivations of the pertinent equations describing the motion of such turbulent flows is provided and an extensive discussion of the various approaches used in predicting both free shear and wall bounded flows is presented. Experimental measurement techniques common to the compressible flow regime are introduced with particular emphasis on the unique challenges presented by high speed flows. Both experimental and numerical simulation work is supplied throughout to provide the reader with an overall perspective of current trends. - An introduction to current techniques in compressible turbulent flow analysis - An approach that enables engineers to identify and solve complex compressible flow challenges - Prediction methodologies, including the Reynolds-averaged Navier Stokes (RANS) method, scale filtered methods and direct numerical simulation (DNS) - Current strategies focusing on compressible flow control
Download or read book Zero Wavenumber Modes of a Compressible Supersonic Mixing Layer written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1990 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 79 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 Compressibility Turbulence and High Speed Flow written by Thomas B. Gatski and published by Elsevier. This book was released on 2009-02-27 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the reader to the field of compressible turbulence and compressible turbulent flows across a broad speed range through a unique complimentary treatment of both the theoretical foundations and the measurement and analysis tools currently used. For the computation of turbulent compressible flows, current methods of averaging and filtering are presented so that the reader is exposed to a consistent development of applicable equation sets for both the mean or resolved fields as well as the transport equations for the turbulent stress field. For the measurement of turbulent compressible flows, current techniques ranging from hot-wire anemometry to PIV are evaluated and limitations assessed. Characterizing dynamic features of free shear flows, including jets, mixing layers and wakes, and wall-bounded flows, including shock-turbulence and shock boundary-layer interactions, obtained from computations, experiments and simulations are discussed. - Describes prediction methodologies including the Reynolds-averaged Navier Stokes (RANS) method, scale filtered methods and direct numerical simulation (DNS) - Presents current measurement and data analysis techniques - Discusses the linkage between experimental and computational results necessary for validation of numerical predictions - Meshes the varied results of computational and experimental studies in both free and wall-bounded flows to provide an overall current view of the field
Download or read book Effect of Heat Release on the Spatial Stability of a Supersonic Reacting Mixing Layer written by T. L. Jackson and published by . This book was released on 1988 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compressible Turbulence Measurement in the Mixing Layer of an Adiabatic Normal Slot Injection Into Supersonic Flow written by Christopher Duane Whitcomb and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Compressible Turbulent Mixing written by and published by . This book was released on 1992 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Mixing Enhancement by Vorticity for High Speed Propulsion written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-16 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of a three year study on vortex enhancement of supersonic mixing are discussed. Recent interests in compressible mixing has spurred research in the field of high speed shear layers. It was established that shear layer growth diminishes with increasing convective Mach number; this Mach number is the relative Mach number of the large scale structures in the shear layer with respect to the Mach numbers on either side of the shear layer. The purpose was to evaluate the effect of swirl on compressible mixing rates. Previously analytical and experimental results seem to indicate that swirling flow may significantly modify the shear layer, in some cases resulting in enhanced mixing. Previous studies of the effect of swirl on compressible mixing were incomplete since the amount of swirl in the flowfield was not quantified. This study was undertaken to conclusively determine the effect of swirl on supersonic mixing, including the quantification of the swirl. Preliminary results indicate that the swirl modestly enhances the mixing rates. Settles, Gary S. Unspecified Center...
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of a Two Dimensional Self Similar Supersonic Turbulent Mixing Layer with Zero Pressure Gradient written by Hideo Ikawa and published by . This book was released on 1973 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of compressibility on the mixing layer was investigated at Mach number 2.47. Pitot pressure, static pressure and hot-wire surveys were made to investigate the mean flow and the fluctuation quantities. Similarities between supersonic and incompressible mixing layers are observed in normalized velocity profile, normalized power spectral density distribution and convection velocity distribution. Spreading rate, normalized shear stress and velocity fluctuation were found to be appreciably smaller than the respective incompressible results; e.g., the momentum thickness growth rates are 0.0073 and 0.035 for supersonic and incompressible flows, respectively. The difference between free and wall-bounded mixing layers is discussed. Development of turbulence structure of mixing layer with increasing Reynolds number was also investigated. (Author).
Download or read book IUTAM Symposium on Variable Density Low Speed Turbulent Flows written by Louis Fulachier and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: The General Assembly of the International Union of Theoretical and Applied Mechanics in its meeting on August 28, 1994, selected for 1996 only four Mechanics Symposia, of which ours is the only one related to Fluid Mechanics: Variable Density Low Speed Turbulent Flows. This IUTAM Symposium, organized by the Institut de Recherche sur les Phenomenes Hors Equilibre (Marseille), is the logical continuation of the meetings previously organized or co-organized - on the French or European level, such as Euromech 237, Marseille, 1988 - by the same research group ofMarseille. This meeting focused specifically on the structure of turbulent flows in which density varies strongly : the effect of this variation on the velocity and scalar fields is in no sense negligible. We were mainly concerned with low-speed flows subjected to strong local changes of density as a consequence of heat or mass transfer or of chemical reactions. Compressible turbulent flows - such a!" supersonic ones - were also considered in order to underline their similarities to and their differences from low-speed variable density flows.
Download or read book A Numerical Investigation of the Compressible Mixing Layer written by N. D. Sandham and published by . This book was released on 1989 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
