Download or read book Laser Diagnostics of Turbulent Flames in High Speed Flows written by Nathan Ryan Grady and published by . This book was released on 2015 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Laser Diagnostics Techniques for Combustion written by Quaid Rafique Vohra and published by . This book was released on 2017 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studying turbulent combustion at the fundamental level is a primary requirement to construct robust, accurate, efficient models to predict the performance of complex combustion systems. Laser based diagnostics offer significant advantage of probing multiple facets of the combustion processes simultaneously and are capable of providing quantitative information of the highly coupled phenomenon. Design of a vitiated co-flow burner is presented for laser diagnostics of turbulent flames. A foundation was laid to be able to perform Rayleigh scattering, Coherent Ani-Stokes Raman Spectroscopy, Heterodyne velocimetry and Particle scattering. Experiment facilities were developed and tests were performed for feasibility, and performance of test equipment. The present work focused on developing facilities for combined diagnostics of, temperature, species, concentration and velocity measurement. Machine vision cameras were studied for their performance with Rayleigh scattering for temperature, high resolution spectrometer is put to test to resolve rotational/vibrational bands from chemiluminesence for species concentration. An optical design for Narrowband CARS is presented. An experimental setup for multiphase turbulent flow is presented and methods were developed for image analysis in a multiphase turbulent flow. An experimental setup for simultaneous measurement of gas species concentration, particle concentration and particle velocity is presented. The final section discusses analysis of diode lasers and optics to perform seedless Laser Heterodyne Velocimetry. The current work also discusses some of the common problems and solutions for laboratory experiments using laser diagnostics.
Download or read book Experimental Study of Laminar and Turbulent Flame Stabilization Using Laser Diagnostics written by Stanislav Kostka and published by . This book was released on 2009 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Premixed Flames written by Nedunchezhian Swaminathan and published by Cambridge University Press. This book was released on 2011-04-25 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: A work on turbulent premixed combustion is important because of increased concern about the environmental impact of combustion and the search for new combustion concepts and technologies. An improved understanding of lean fuel turbulent premixed flames must play a central role in the fundamental science of these new concepts. Lean premixed flames have the potential to offer ultra-low emission levels, but they are notoriously susceptible to combustion oscillations. Thus, sophisticated control measures are inevitably required. The editors' intent is to set out the modeling aspects in the field of turbulent premixed combustion. Good progress has been made on this topic, and this cohesive volume contains contributions from international experts on various subtopics of the lean premixed flame problem.
Download or read book Optical and Laser Diagnostics written by C Arcoumanis and published by CRC Press. This book was released on 2016-04-19 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the automotive industry to blood flow monitoring, optical techniques and laser diagnostics are becoming integral parts in engineering and medical instrumentation. Written by leading global experts from industry, academic groups, and laboratories, this volume provides an international perspective on both existing applications and leading-edge r
Download or read book Study of Turbulent Burning Velocity Using Laser Diagnostics in Turbulent Premixed Flames written by Sergei Aleksandrovich Filatyev and published by . This book was released on 2003 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow and Combustion in Advanced Gas Turbine Combustors written by Johannes Janicka and published by Springer Science & Business Media. This book was released on 2012-10-29 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: With regard to both the environmental sustainability and operating efficiency demands, modern combustion research has to face two main objectives, the optimization of combustion efficiency and the reduction of pollutants. This book reports on the combustion research activities carried out within the Collaborative Research Center (SFB) 568 “Flow and Combustion in Future Gas Turbine Combustion Chambers” funded by the German Research Foundation (DFG). This aimed at designing a completely integrated modeling and numerical simulation of the occurring very complex, coupled and interacting physico-chemical processes, such as turbulent heat and mass transport, single or multi-phase flows phenomena, chemical reactions/combustion and radiation, able to support the development of advanced gas turbine chamber concepts
Download or read book Theories of Turbulent Combustion in High Speed Flows written by and published by . This book was released on 1993 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research involves theoretical studies of the chemical and fluid mechanical phenomena which make turbulent combustion in high-speed flows different from such combustion in low-speed flows. Finite-rate chemistry plays a significant role in high-speed flows because of the small ratios of flow times to chemical times. The studies address ignition and extinction phenomena in nonpremixed turbulent combustion of hydrogen-air systems by both numerical and asymptotic methods. Attention also is paid to effects of compressibility in high-speed turbulent combustion, with consideration given to interdispersal configurations of shocklets and flamelets. Efforts are made to provide a firmer foundation for the modeling of high-speed turbulent reacting flows, to aid in the development of a formulation which gives results that can be compared with experiments, on turbulent combustion ... Turbulent flames, Diffusion flames, Supersonic combustion.
Download or read book Coherent Structures in Turbulent Flames written by A. J. Yule and published by . This book was released on 1979 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diagnostic and data analysis techniques have been used to investigate the structure of turbulent jet reacting flows with well defined initial and boundary conditions. In the transition region of a turbulent jet flame a double-vortex structure has been found: with outer vortices, which may originate from Kelvin-Helmholtz or Rayleigh type instabilities, and inner vortices which are influenced strongly by one or more combustion instability mechanisms. Measurements of mean velocity, turbulence intensity, ionization current, mean temperature and peak frequencies are presented together with data derived from high speed color schlieren photography and laser schlieren spectra.
Download or read book Advanced Diagnostics in Combustion Science written by Zhen-Yu Tian and published by Springer Nature. This book was released on 2023-07-12 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook, supported by the Textbook Publishing Center of University of Chinese Academy of Sciences, provides a fundamental introduction to advanced diagnostics techniques for graduate students majoring in combustion science, chemistry, and chemical engineering-related subjects. The textbook provides an overview with respect to the spectroscopic methods in advanced diagnostics techniques such as gas chromatography/mass spectrometry, thermochemical analysis, Raman scattering, and nuclear magnetic resonance. It then describes the comprehensive basic theory, equipment structure, and testing methods of diagnostic techniques and summarizes the analysis methods commonly used in combustion chemical reaction processes. This can provide graduate students with important guidance and comprehensive understanding of diagnostics techniques before performing physics and chemistry experiments. In addition, it provides an introduction into using common mathematical and graphics packages for students to acquire and practice the tools to comply with international standards. The textbook is concise and illustrative and includes hot issues and current progress of diagnostics. In addition, exercises and questions are included at the end of each chapter for students to practice and gain hands-on experience. Given its scope, the textbook is of great benefit to graduate students in combustion chemistry and engineering and other related areas such as environmental science, optical engineering, and thermal science and is also beneficial for researchers with interdisciplinary backgrounds.
Download or read book Propagation of Free Flames in Laminar and Turbulent flow Fields written by Ray E. Bolz and published by . This book was released on 1960 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Combustion Diagnostics written by KoHse-HoingHaus and published by Taylor & Francis US. This book was released on 2002-04-26 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: The editors have assembled a world-class group of contributors who address the questions the combustion diagnostic community faces. They are chemists who identify the species to be measured and the interfering substances that may be present; physicists, who push the limits of laser spectroscopy and laser devices and who conceive suitable measurement schemes; and engineers, who know combustion systems and processes. This book assists in providing guidance for the planning of combustion experiments, in judging research strategies and in conceiving new ideas for combustion research. It provides a snapshot of the available diagnostic methods and thier typical applications from the perspective of leading experts in the field.
Download or read book The Micro World Observed by Ultra High Speed Cameras written by Kinko Tsuji and published by Springer. This book was released on 2017-08-30 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is about ultra high-speed cameras, which enable us to see what we normally do not see. These are objects that are moving very fast, or that we just ignore. Ultra high-speed cameras invite us to a wonderland of microseconds. There Alice (the reader) meets a ultra high-speed rabbit (this volume) and travels together through this wonderland from the year 1887 to 2017. They go to the horse riding ground and see how a horse gallops. The rabbit takes her to a showroom where various cameras and illumination devices are presented. Then, he sends Alice into semiconductor labyrinths, wind tunnels, mechanical processing factories, and dangerous explosive fields. Sometimes Alice is large, and at other times she is very small. She sits even inside a car engine. She falls down together with a droplet. She enters a microbubble, is thrown out with a jet stream, and finds herself in a human body. Waking up from her dream, she sees children playing a game: “I see what you do not see, and this is....”. Alice thinks: “The ultra high-speed rabbit showed me many things which I had never seen. Now I will go again to this wonderland, and try to find something new.
Download or read book Combustings Flow Diagnostics written by D.F.G. Durão and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of papers prepared for and presented at a NATO sponsored Advanced Study Institute which was held in Montechoro, Portugal during the period 16-27 April, 1990. This Institute was attended by approximately ninety delegates from fifteen countries and followed from a related Institute held in Vimeiro, Portugal in 1987 (see the book entitled "Instrumentation for Combustion and Flow in Engines", edited by D. F. G. Dur~o, J. H. Whitelaw and P. O. Witzel. The purposes of the first Institute related closely to instrumentation for use in gas-turbine combustors and the cylinders of internal-combustion engines. These topics were also addressed in the second Institute, though in a manner which was wider ranging and chosen to demonstrate and explain the development and application of measurement methods to combusting flows in general. The papers contained in this boo~ were selected to provide the reader with a comprehensive and up-to-date view of the variety of experimental techniques available to measure in combusting flows. Included are discussions of their range and applicability, potential accuracy and ease of use. Thus, the first paper provides a brief overview and the second an indication of those aspects of combustion which should influence the choice of flow property to be measured and the technique to be used.
Download or read book Advanced Turbulent Combustion Physics and Applications written by N. Swaminathan and published by Cambridge University Press. This book was released on 2022-01-06 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Explore a thorough and up to date overview of the current knowledge, developments and outstanding challenges in turbulent combustion and application. The balance among various renewable and combustion technologies are surveyed, and numerical and experimental tools are discussed along with recent advances. Covers combustion of gaseous, liquid and solid fuels and subsonic and supersonic flows. This detailed insight into the turbulence-combustion coupling with turbulence and other physical aspects, shared by a number of the world leading experts in the field, makes this an excellent reference for graduate students, researchers and practitioners in the field.
Download or read book The Interaction of High Speed Turbulence with Flames Turbulent Flame Speed written by and published by . This book was released on 2010 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct numerical simulations of the interaction of a premixed flame with subsonic, high-speed, homogeneous, isotropic, Kolmogorov-type turbulence in an unconfined system show anomalously high turbulent flame speeds, S(T) . Data from these simulations are analyzed to identify the origin of this anomaly. The simulations were performed with Athena-RFX, a massively parallel, fully compressible, high-order, dimensionally unsplit, reactive-flow code. A simplified reaction-diffusion model represents a stoichiometric H2-air mixture under the assumption of the Lewis number L(e) = 1. Global properties and the internal structure of the flame were analyzed in an earlier paper, which showed that this system represents turbulent combustion in the thin reaction zone regime with the average local flame speed equal to its laminar value, S(L). This paper shows that: (1) Flamelets inside the flame brush have a complex internal structure, in which the isosurfaces of higher fuel mass fractions are folded on progressively smaller scales. (2) Global properties of the turbulent flame are best represented by the structure of the region of peak reaction rate, which defines the flame surface. (3) The observed increase of S(T) relative to S(L) exceeds the corresponding increase of the flame surface area, A(T), relative to the surface area of the planar laminar flame, on average, by 30% and occasionally by as much as 50% in the course of system evolution. This exaggerrated response of S(T) shows that Damkohler's paradigm breaks down for sufficiently high-intensity turbulence, namely at Karlovitz numbers Ka ~ 20, even in the flows characterized by L(e) = 1. (4) The breakdown is the result of tight flame packing by turbulence, which causes frequent flame collisions and formation of regions of high flame curvature 1/ L, or "cusps," where L is the thermal width of the laminar flame.
Download or read book Freely Propagating Open Premixed Turbulent Flames Stabilized by Swirl written by and published by . This book was released on 1991 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel means has been developed for using weak swirl to stabilize freely propagating open premixed turbulent flames (swirl numbers between 0.05 to 0.3). By injecting a small amount of air tangentially into the co-flow of a concentric burner, stationary flames can be maintained above the burner exit for a large range of mixture, turbulence and flow conditions. The absence of physical surfaces in the vicinity of the flame provides free access to laser diagnostics. Laser Doppler anemometry and laser Mie scattering measurements of four flames with and without incident turbulence show that their features are typical of wrinkled laminar flames. The most distinct characteristics is that flame stabilization does not rely on flow recirculation. Centrifugal force induced by swirl causes flow divergence, and the flame is maintained at where the local mass flux balances the burning rate. The flame speeds can be estimated based on the centerline velocity vector, which is locally normal to the flame brush. This flame geometry is the closest approximation to the 1-D planar flame for determining fundamental properties to advance turbulent combustion theories. 18 refs.
