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 High Resolution Measurements of Supersonic Shear Flow Mixing and Combustion written by Werner Dahm and published by . This book was released on 1998 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: An initial experimental study of the effects of compressibility on the outer variable scalings and large-scale structure of a supersonic coflowing turbulent jet operating in the wake-like mode was completed. The results showed that the large-scale structure is clearly evident in the downstream portion of the flow, where the convective Mach number has become subsonic. However the structures appear to be suppressed in the upstream portion of the flow, at supersonic convective Mach numbers. The results also showed that the local flow width and growth rate in the downstream portions of the flow are good in agreement with the scaling laws for the corresponding incompressible flow.
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 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 Jet in Supersonic Crossflow written by Mingbo Sun and published by Springer. This book was released on 2019-02-18 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on research into jets in supersonic crossflow carried out by the authors’ team over the past 15 years, this book summarizes and presents many cutting-edge findings and analyses on this subject. It tackles the complicated mixing process of gas jets and atomization process of liquid jets in supersonic crossflow, and studies their physical mechanisms. Advanced experimental and numerical techniques are applied to further readers’ understanding of atomization, mixing, and combustion of fuel jets in supersonic crossflow, which can promote superior fuel injection design in scramjet engines. The book offers a valuable reference guide for all researchers and engineers working on the design of scramjet engines, and will also benefit graduate students majoring in aeronautical and aerospace engineering.
Download or read book An Investieation of Supersonic Combustion and Heterogeneous Turbulent Jet Mixing Related to the Design operation of Scram Jets written by Ian Thomas Osgerby and published by . This book was released on 1965 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation with an Interferometer of the Turbulent Mixing of a Free Supersonic Jet written by Paul B. Gooderum and published by . This book was released on 1949 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: The free turbulent mixing of a supersonic jet was investigated with an interferometer, of which a description is given. Density and velocity distributions through the mixing zone were obtained. The velocity distribution was found to be similar to those for imcompressible jets over only the subsonic portion of the mixing pattern.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Investigation of Supersonic Combustion and Heterogeneous Turbulent Jet Mixing Related to the Design operation of Scramjets written by Ian Thomas Osgerby and published by . This book was released on 1965 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical kinetic calculations of the combustion time in a constant area scramjet combustion (Mo=7) indicate reaction times 0.00001 secs., and show that the combustion process is usually controlled by diffusion. The mixing process in concentric fueld/air jets is investigated by means of integral forms of the equations of motion and slow mixing requires about 50 diameter. Initial contraction of the slow inner jet is predicted by the theory, and verified by experiment. The simulation of scramjet combustion conditions by a shock tunnel is considered feasible. (Author).
Download or read book Supersonic Jet Exhaust Noise Investigation Volume II Technical Report written by Paul R. Knott and published by . This book was released on 1976 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report discusses detailed accounts of major theoretical and experimental investigations directed toward obtaining better understanding and mathematical specification of supersonic turbulent jets. Complete theoretical discussions are given describing the influence of a jet's mean flow shrouding on acoustic radiation of heated and unheated jets, approximate closed form acoustic expressions for turbulent mixing noise characterized by self-noise and shear-noise are given, and theoretical aero-acoustic formulations for the orderly structure of supersonic jets are reviewed. Extensive theory/data comparisons of developed acoustic models are given. Experimental investigations aimed at studying high velocity jet refraction, and the influence of jet swirl and upstream combustion roughness on jet noise is presented. Additionally, an extensive series of laser velocimeter measurements for high velocity and high temperature simple circular jets is discussed. Results include hot-film/laser velocimeter comparisons for ambient jets, mean velocity and turbulent velocity plume surveys of heated supersonic shock-free and shocked flow nozzles, and a demonstration experiment illustrating the capability of performing in-jet turbulence to far-field acoustic cross-correlation. (Author).
Download or read book Supersonic Mixing of Two phase Co flowing Jets written by Clayton LaPointe and published by . This book was released on 1970 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Mixing of Jets and Turbulent Boundary Layers written by Harry Edward Bailey and published by . This book was released on 1958 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Mixing in Supersonic High temperature Exhaust Jets written by Lei-Yong Jiang and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1996 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Mixing and Combustion of a Hydrogen Jet in a Coaxial High temperature Test Gas written by H. L. Beach and published by . This book was released on 1972 with total page 10 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 Piv Measurements of Supersonic Internally Mixed Dual Stream Jets written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-22 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: While externally mixed, or separate flow, nozzle systems are most common in high bypass-ratio aircraft, they are not as attractive for use in lower bypass-ratio systems and on aircraft that will fly supersonically. The noise of such propulsion systems is also dominated by jet noise, making the study and noise reduction of these exhaust systems very important, both for military aircraft and future civilian supersonic aircraft. This paper presents particle image velocimetry of internally mixed nozzle with different area ratios between core and bypass, and nozzles that are ideally expanded and convergent. Such configurations independently control the geometry of the internal mixing layer and of the external shock structure. These allow exploration of the impact of shocks on the turbulent mixing layers, the impact of bypass ratio on broadband shock noise and mixing noise, and the impact of temperature on the turbulent flow field. At the 2009 AIAA/CEAS Aeroacoustics Conference the authors presented data and analysis from a series of tests that looked at the acoustics of supersonic jets from internally mixed nozzles. In that paper the broadband shock and mixing noise components of the jet noise were independently manipulated by holding Mach number constant while varying bypass ratio and jet temperature. Significant portions of that analysis was predicated on assumptions regarding the flow fields of these jets, both shock structure and turbulence. In this paper we add to that analysis by presenting particle image velocimetry measurements of the flow fields of many of those jets. In addition, the turbulent velocity data documented here will be very useful for validation of computational flow codes that are being developed to design advanced nozzles for future aircraft. Bridges, James E. and Wernet, Mark P. Glenn Research Center PARTICLE IMAGE VELOCIMETRY; SUPERSONIC JET FLOW; AIRPORTS; AIRCRAFT NOISE; SUPERSONIC AIRCRAFT; AEROACOUSTICS; DIRECTIVITY; FAR FIELDS; NOISE REDUCTION; NOZZLE FLOW; CONVERGENT-DIVERGENT NOZZLES; BYPASS RATIO; FLOW DISTRIBUTION
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:
