Download or read book Experimental and Theoretical Investigation of Flame Propagation Through Compositionally Stratified Methane Air Mixtures written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Investigation of Flame Propagation in Methane air Mixtures in Circular Tubes written by Been-Jhy Houng and published by . This book was released on 1981 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ignition and Flame Propagation Within Stratified Methane air Mixtures Formed by Convective Diffusion microform written by Hei Tung Lam and published by National Library of Canada. This book was released on 1984 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Investigation of the Flame Propagation Through a Stratified Mixture written by Keshav S. Varde and published by . This book was released on 1971 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Methane Flame Propagation in a Compositionally Stratified Gas written by Taekyu Kang and published by . This book was released on 2005 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Flame Propagation Characteristics in Layered Gas Mixtures written by Israel Liebman and published by . This book was released on 1968 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Formation and Flammability of Stratified Methane air Mixtures written by Henry E. Perlee 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 On the Experimental and Theoretical Investigations of Lean Partially Premixed Combustion Burning Speed Flame Instability and Plasma Formation of Alternative Fuels at High Temperatures and Pressures written by Omid Askari and published by . This book was released on 2016 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation investigates the combustion and injection fundamental characteristics of different alternative fuels both experimentally and theoretically. The subjects such as lean partially premixed combustion of methane/hydrogen/air/diluent, methane high pressure direct-injection, thermal plasma formation, thermodynamic properties of hydrocarbon/air mixtures at high temperatures, laminar flames and flame morphology of synthetic gas (syngas) and Gas-to-Liquid (GTL) fuels were extensively studied in this work. These subjects will be summarized in three following paragraphs. The fundamentals of spray and partially premixed combustion characteristics of directly injected methane in a constant volume combustion chamber have been experimentally studied. The injected fuel jet generates turbulence in the vessel and forms a turbulent heterogeneous fuel-air mixture in the vessel, similar to that in a Compressed Natural Gas (CNG) Direct-Injection (DI) engines. The effect of different characteristics parameters such as spark delay time, stratification ratio, turbulence intensity, fuel injection pressure, chamber pressure, chamber temperature, Exhaust Gas recirculation (EGR) addition, hydrogen addition and equivalence ratio on flame propagation and emission concentrations were analyzed. As a part of this work and for the purpose of control and calibration of high pressure injector, spray development and characteristics including spray tip penetration, spray cone angle and overall equivalence ratio were evaluated under a wide range of fuel injection pressures of 30 to 90 atm and different chamber pressures of 1 to 5 atm. Thermodynamic properties of hydrocarbon/air plasma mixtures at ultra-high temperatures must be precisely calculated due to important influence on the flame kernel formation and propagation in combusting flows and spark discharge applications. A new algorithm based on the statistical thermodynamics was developed to calculate the ultra-high temperature plasma composition and thermodynamic properties. The method was applied to compute the thermodynamic properties of hydrogen/air and methane/air plasma mixtures for a wide range of temperatures (1,000-100,000 K), pressures (10−6-100 atm) and different equivalence ratios within flammability limit. In calculating the individual thermodynamic properties of the atomic species, the Debye-Huckel cutoff criterion has been used for terminating the series expression of the electronic partition function. A new differential-based multi-shell model was developed in conjunction with Schlieren photography to measure laminar burning speed and to study the flame instabilities for different alternative fuels such as syngas and GTL. Flame instabilities such as cracking and wrinkling were observed during flame propagation and discussed in terms of the hydrodynamic and thermo-diffusive effects. Laminar burning speeds were measured using pressure rise data during flame propagation and power law correlations were developed over a wide range of temperatures, pressures and equivalence ratios. As a part of this work, the effect of EGR addition and substitution of nitrogen with helium in air on flame morphology and laminar burning speed were extensively investigated. The effect of cell formation on flame surface area of syngas fuel in terms of a newly defined parameter called cellularity factor was also evaluated. In addition to that the experimental onset of auto-ignition and theoretical ignition delay times of premixed GTL/air mixture were determined at high pressures and low temperatures over a wide range of equivalence ratios.

Download or read book THEORETICAL INVESTIGATION OF ONE DIMENSIONAL FLAME PROPAGATION written by J. E. BROADWELL, J. R. SELLARS and published by . This book was released on 1955 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of Flame Propagation Through Step Changes in Mixture Composition written by Caroline Sørensen (S.M.) and published by . This book was released on 2016 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flame speed is a central metric in the field of combustion. While particular mixtures have characteristic flame speeds, it has also been shown that in compositionally stratified mixtures, flames exhibit a path dependency, or memory effect. The goal of the experimental work presented in this thesis was to investigate the behavior of flame speed over step changes in equivalence ratios. This sharp stratification was achieved using a soap bubble blown at the center of a combustion bomb. A laser was used to ignite the mixture from the center. Flame speed was calculated from both a pressure trace analysis and from measuring the movement of the flame front through high speed Schlieren imaging. Both methods demonstrated good correlation with the literature for homogeneous charges. However, the analysis necessarily assumes a spherical flame, but the Schlieren video showed that the laser ignition system induced a significant protrusion in the flame front. This protrusion smooths the transition from the flame speed of the inner mixture to that of the outer. Therefore, it was demonstrated that this setup is not suitable for the measurement of flame speed transitional behavior over step-changes in equivalence ratio.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2008 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation Into Combustion Torch Jet Ignition of Methane air Ethylene air and Propane air Mixtures written by Ukwatte Lokuliyanage Indika Upendra Perera and published by . This book was released on 2010 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ignitability and the ignition delay time of a combustible mixture in a long combustion chamber, ignited by a hot combustion torch jet generated in a pre-chamber was investigated experimentally in relation to application as a viable igniter method for wave rotor combustors. Methane-air, ethylene-air, and propane-air in varying equivalence ratios were investigated as the combustible mixture in the combustion chamber. The effects of variation in the torch jet fuel, initial equivalence ratio in the pre-chamber, and nozzle geometry on the ignitability and the ignition delay time of combustible mixtures were observed and analyzed. The single-channel wave-rotor combustion rig at Combustion and Propulsion Research Laboratory at the Purdue School of Engineering and Technology at Indiana University-Purdue University, Indianapolis was used for this study. High-speed video imaging techniques to observe the ignition and flame propagation in the combustion chamber and fast-response pressure transducers to measure the dynamic pressure fluctuations in the combustion chambers were used in the current study. The present work explains how the experimental procedure and preliminary testing was carried out in order to conduct the necessary testing to find the ignitability and ignition delay time of a combustible mixture. Ignitability of methane, ethylene, and propane were much broader in range compared to conventional spark ignitable lean and rich limit equivalence ratios. The methane and propane ignition lean limits were similar to radical activated ignition lean limits found in previous studies of the same fuels. Ethylene exhibited the widest range in equivalence ratios from 0.4 to 2.4, while methane had the narrowest ranging from equivalence ratio 0.4 to 1.4. The ignition delay studies indicated both chemical kinetics and mixing between the combustion torch jet and the combustible mixture were critical. The mixing phenomena dominated chemical kinetics; unlike in ignition delay studies conducted using shock heated ignition techniques. Ethylene-air mixtures had the shortest ignition delay times ~1 ms for lean but near-stoichiometric mixtures. Methane and propane indicated similar ignition delay time characteristics with lean near-stoichiometric mixtures. The fuel-air equivalence ratio which was used to generate the combustion torch jet and the torch jet nozzle geometry had a direct influence over the ignition delay time in the main chamber combustible mixture. The slightly rich fuel-air ratios used to generate the combustion torch jet had the lowest delay times in igniting the main chamber fuel-air mixtures.

Download or read book Flame Propagation Through Methane air Mixtures Involving Concentration Gradients Formed by Mass Transfer Phenomena written by Tsang, Peter W and published by 1974.. This book was released on 1974 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Theoretical Study of the Kinetics Propagation and Suppression of Methane air Flames written by William C. Hecker and published by . This book was released on 1975 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flame Propagation in Mixtures of Natural Gas and of Methane with Air written by C. G. Dunkle and published by . This book was released on 1926 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Preliminary Investigation of Flame Propagation in Stratified Media microform written by Tsang, P. W and published by National Library of Canada. This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Discrete Flame Propagation Regime in Particulate Suspensions written by Alex Wright and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Suspensions of solid metal powders burning in a gaseous oxidizer can be modelled as a reaction-diffusion wave propagating through a heterogeneous mixture with discrete energetic sources. This is in contrast with more conventional models of flame propagation in areas such as gas combustion, where the reaction front and heat release profiles are homogenized continuous features. Under certain conditions the spatial dependence of the source term becomes important, and may affect the behaviour of the flame. This so-called discrete regime has lacked sufficient experimental verification. The present thesis discusses microgravity-based experiments that were performed, and introduces new lab-based experimental techniques for observing flames propagating in this discrete regime. Flame speed measurements corroborated the theoretical predictions, namely, an independence of flame speed upon oxygen concentration. Instabilities associated with metal dust flames were also investigated. Another fundamental property of solid fuels is their particle burn time. This parameter is important for determining the discreetness of a mixture, and supporting experiments were performed to determine the burning time of micron-sized iron powder particles. It was seen that the combustion process can terminate with either gradual burnout or premature explosion, depending on composition. The burn time results showed qualitative agreement with theoretical predictions. This work will support experiments on a sounding rocket microgravity platform scheduled for launch in 2016." --