EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Study of Opposed Jet Diffusion Flame

Download or read book Study of Opposed Jet Diffusion Flame written by Pravin V. Ajmera and published by . This book was released on 1965 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Studies of Opposed Jet Diffusion Flames

Download or read book Studies of Opposed Jet Diffusion Flames written by Natver Kasanji Patel and published by . This book was released on 1973 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Study of Opposed jet Diffusion Flames Under Impressed Electric Fields

Download or read book A Study of Opposed jet Diffusion Flames Under Impressed Electric Fields written by Bernard J. Rezy and published by . This book was released on with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Computational Study of Dry CO O2 Opposed jet Diffusion Flame and Its Flammability Limits

Download or read book A Computational Study of Dry CO O2 Opposed jet Diffusion Flame and Its Flammability Limits written by Franco Carmine Frate and published by . This book was released on 2000 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Opposed Jet Turbulent Diffusion Flames

Download or read book Opposed Jet Turbulent Diffusion Flames written by Lawrence Talbot and published by . This book was released on 1990 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Hydrocarbon atomic Oxygen Opposed Jet Diffusion Flame Studies

Download or read book Hydrocarbon atomic Oxygen Opposed Jet Diffusion Flame Studies written by Vinay L. Tejani and published by . This book was released on 1972 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Temperature Study of H2 air Opposed Jet Diffusion Flames

Download or read book Temperature Study of H2 air Opposed Jet Diffusion Flames written by S. Yeralan and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Modeling of Hydrogen Air Diffusion Flame

Download or read book Modeling of Hydrogen Air Diffusion Flame written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-28 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work performed during the first six months of the project duration for NASA Grant (NAG-1-861) is reported. An analytical and computational study of opposed jet diffusion flame for the purpose of understanding the effects of contaminants in the reactants and thermal diffusion of light species on extinction and reignition of diffusion flames is in progress. The methodologies attempted so far are described. Isaac, K. M. NASA-CR-181357, NAS 1.26:181357 NAG1-861...

Book Flammability Study of Polymer Fuels Using Opposed Jet Diffusion Flame Technique

Download or read book Flammability Study of Polymer Fuels Using Opposed Jet Diffusion Flame Technique written by Surendra N. Singhal and published by . This book was released on with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments emphasizying the extinction phenomena and the near-limit burning characteristics are performed on polymers, PMMA (Polymethylmethacrylate) and Delrin, using an Opposed-Jet Diffusion Flame apparatus. The measurements include burning rate and peak flame temperature and the variables are jet velocity and the oxidizer mole fraction. The measurements indicate the burning rate in the near-limit region departs from a power law relationship indicating the importance of finite rate chemical kinetics in this regime. Consistently, the peak flame temperature measurements prior to extinction show a sharp rate of decrease. Extinction does not occur on a sharp boundary in the oxygen mole fraction-jet velocity plane, but rather in a region (its size may depend on the experimental set-up and external disturbances) wherein extinction occurs in a random manner. The extinction statistics suggest that this is due to the quenching sensitivity of the near-limit flame to disturbances. Determination of chemical kinetic data using extinction 'boundary' is likely to have scatters due to the finiteness of the extinction region. It is suggested that matching of the burning rate curve in the near limit regime may give more reliable chemical kinetic data. (Author).

Book On the Extinction of Opposed jet Diffusion Flames a Physical Criterion for Extinction

Download or read book On the Extinction of Opposed jet Diffusion Flames a Physical Criterion for Extinction written by R. F. Chaiken and published by . This book was released on 1965 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A physical criterion for the extinction of opposed-jet diffusion flames is presented. This criterion, when used in conjunction with the Spalding Theory of mixing in opposed-gas jets, enables the apparent flame strength to be related to (1) the effective maximum chemical reaction rate in the opposed-jet flame, and (2) the laminar flame speed of an equivalent pre-mixed diffusion flame. The derived relationships differ somewhat from similar relationships given by Spalding's earlier theoretical treatment of the phenomena in the thin-flame approximation, but do yield quantitatively similar results when compared with experimental data reported for opposed-jet diffusion flames involving oxidation of simple hydrocarbons and ammonia. (Author).

Book Burner Stabilities of Jet Diffusion Flames

Download or read book Burner Stabilities of Jet Diffusion Flames written by James Phillip Seaba and published by . This book was released on 1990 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: The near field lift-off phenomena associated with jet diffusion flames were investigated. Lift-off is defined as the instant when the luminous flame zone detaches from the burner exit, stabilizing itself downstream. The lift-off of the jet diffusion flames were studied using a fuel jet centered in a large coflowing air annulus. Fuels used consisted of methane and propane. The fuels are diluted with nitrogen, argon, and helium. Annulus, diluted fuel, and external nozzle geometry effects are studied for the jet diffusion flame. The jet diffusion flame is sensitive to the annulus velocity, the lift-off velocity decreasing with increasing annular velocity. Lift-off velocity decreases as dilution concentrations of the fuel jet increase. The external geometry effects influence the lift-off velocity, especially at higher annular flow rates. Two theories have explained the lift-off of jet diffusion flames. The locally premixed theory which assumes that the fuel and oxidant are fully premixed prior to combustion. The lift-off of the flame zone occurs due to the convective velocity of the premixed reactants exceeding the local flame speed. The second theory, the laminar flamelet model, states that the diffusion of reactants into the flame zone exceeds the chemical reaction rate, causing the flame to extinguish at the flame base, lifting the flame from the nozzle to a position downstream. The two models were evaluated by the different lift-off velocities produced by annulus and diluent effects. Laser Doppler anemometry (LDA) was used to characterize the flow field at and near the base of the jet diffusion flame. The local straining rate across the flame was approximated by the gradient of the mean radial velocity in the radial direction for the pure and diluted methane conditions. The straining rate was in qualitative agreement with that reported in the literature for counter-flow methane diffusion flames near extinction.

Book Two Dimensional Direct Numerical Simulation of Opposed Jet Hydrogen Air Flames Transition From a Diffusion to an Edge Flame

Download or read book Two Dimensional Direct Numerical Simulation of Opposed Jet Hydrogen Air Flames Transition From a Diffusion to an Edge Flame written by and published by . This book was released on 2000 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: In an opposed-jet diffusion flame experiment, under certain conditions, after the extinction of the diffusion flame, an edge flame can be obtained. It was reported recently in a numerical and an experimental work and is responsible for an interesting transition between two distinct burning flames (multiple solutions). Motivated by our previous numerical results, obtained with simplified kinetics and some recently reported experimental data, we performed direct numerical simulations of this transition to investigate the underlying physical mechanisms. The appearance of an edge flame after the extinction of the diffusion flame, the hysteresis reported in the experiments, and the existence of multiple vigorously burning flames at identical conditions are all captured by our simulations. Our numerical results show that, in the absence of an inert coflow curtain, when the diffusion flame disk is extinguished, an edge flame forms and propagates in the mixing layer. After the formation of this edge flame, even when the applied strain rate is reduced to the initial subcritical value, the diffusion flame disk does not reappear, because the local fluid velocity still exceeds the propagation speed of the edge flame. This hysteresis has significant implications in the common submodel that utilizes the strain rate as a parameter to determine local reignition in flamelet models; it indicates that a subcritical strain rate is not a sufficient condition for the reignition of a diffusion flame. Further investigation of this phenomenon is clearly needed to refine submodels of local extinction and reignition in the flamelet models for turbulent diffusion flames. The opposed-jet configuration provides a convenient platform to analyze edge flames which are stabilized aerodynamically in a two-dimensional geometry, thus making matching two-dimensional direct numerical simulations effective.