Download or read book Kinetic Mechanisms for Premixed Laminar Steady State Hydrogen Nitrous Oxide Flames written by and published by . This book was released on 1986 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report pertains to the detailed kinetics governing premixed, laminar, one-dimensional hydrogen/nitrous oxide flames. The long range goal is to understand the kinetics governing propellant decomposition, where nitrogen chemistry is important. Hydrogen/nitrous oxide flames are the simplest case of a flame controlled by nitrogen chemistry. A model has been developed for premixed, laminar, one-dimensional hydrogen/nitrous oxide flames. Results have been compared with a range of experimental data. The present model roughly reproduces the data, but inaccuracies still exist. Sensitivity and screening analyses have been used to indicate the additional experimental data needed to improve the model. Keywords: Burning Velocity.
Download or read book Kinetic Mechanisms for Premixed Laminar Steady State Methane Air Flames written by T. P. Coffee and published by . This book was released on 1983 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: A number of kinetic schemes have been used to model premixed, laminar, one-dimensional methane/air flames. Seven such kinetic schemes, including two new models, are compared with one another and with experimental data. The two new models, one with 14 species and one with 20 species, both agree with the experimental data over a range of stoichiometries from lean to rich. All of the models show good agreement for lean to slightly rich flames. This does not validate any of the models, even for this limited range. Rather, it is shown that the quantities measured are fairly insensitive to much of the mechanism. Therefore, models with incorrect kinetics can agree with the experimental data. In particular, the contribution of the C2 species to methane combustion is examined. While these species are important, we conclude that there is insufficient data to determine quantitatively the effects of the C2 chemistry reactions.
Download or read book Reduced Kinetic Mechanisms for Applications in Combustion Systems written by Norbert Peters and published by Springer Science & Business Media. This book was released on 2008-09-11 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: In general, combustion is a spatially three-dimensional, highly complex physi co-chemical process oftransient nature. Models are therefore needed that sim to such a degree that it becomes amenable plify a given combustion problem to theoretical or numerical analysis but that are not so restrictive as to distort the underlying physics or chemistry. In particular, in view of worldwide efforts to conserve energy and to control pollutant formation, models of combustion chemistry are needed that are sufficiently accurate to allow confident predic tions of flame structures. Reduced kinetic mechanisms, which are the topic of the present book, represent such combustion-chemistry models. Historically combustion chemistry was first described as a global one-step reaction in which fuel and oxidizer react to form a single product. Even when detailed mechanisms ofelementary reactions became available, empirical one step kinetic approximations were needed in order to make problems amenable to theoretical analysis. This situation began to change inthe early 1970s when computing facilities became more powerful and more widely available, thereby facilitating numerical analysis of relatively simple combustion problems, typi cally steady one-dimensional flames, with moderately detailed mechanisms of elementary reactions. However, even on the fastest and most powerful com puters available today, numerical simulations of, say, laminar, steady, three dimensional reacting flows with reasonably detailed and hence realistic ki netic mechanisms of elementary reactions are not possible.
Download or read book Fossil Energy Update written by and published by . This book was released on 1978 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reduced Kinetic Mechanisms for Premixed Laminar Flames written by Weigang Wang and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetic Mechanism Structure and Properties of Premixed Flames in Hydrogen oxygen nitrogen Mixtures written by G. Dixon Lewis and published by . This book was released on 1979 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Kinetic Modeling of Hydrogen Combustion Limits written by and published by . This book was released on 2008 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed chemical kinetic model is used to explore the flammability and detonability of hydrogen mixtures. In the case of flammability, a detailed chemical kinetic mechanism for hydrogen is coupled to the CHEMKIN Premix code to compute premixed, laminar flame speeds. The detailed chemical kinetic model reproduces flame speeds in the literature over a range of equivalence ratios, pressures and reactant temperatures. A series of calculation were performed to assess the key parameters determining the flammability of hydrogen mixtures. Increased reactant temperature was found to greatly increase the flame speed and the flammability of the mixture. The effect of added diluents was assessed. Addition of water and carbon dioxide were found to reduce the flame speed and thus the flammability of a hydrogen mixture approximately equally well and much more than the addition of nitrogen. The detailed chemical kinetic model was used to explore the detonability of hydrogen mixtures. A Zeldovich-von Neumann-Doring (ZND) detonation model coupled with detailed chemical kinetics was used to model the detonation. The effectiveness on different diluents was assessed in reducing the detonability of a hydrogen mixture. Carbon dioxide was found to be most effective in reducing the detonability followed by water and nitrogen. The chemical action of chemical inhibitors on reducing the flammability of hydrogen mixtures is discussed. Bromine and organophosphorus inhibitors act through catalytic cycles that recombine H and OH radicals in the flame. The reduction in H and OH radicals reduces chain branching in the flame through the H + O2 = OH + O chain branching reaction. The reduction in chain branching and radical production reduces the flame speed and thus the flammability of the hydrogen mixture.
Download or read book Transition to Renewable Energy Systems written by Detlef Stolten and published by John Wiley & Sons. This book was released on 2013-05-13 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this ready reference, top academic researchers, industry players and government officers join forces to develop commercial concepts for the transition from current nuclear or fossil fuel-based energy to renewable energy systems within a limited time span. They take into account the latest science and technology, including an analysis of the feasibility and impact on the environment, economy and society. In so doing, they discuss such complex topics as electrical and gas grids, fossil power plants and energy storage technologies. The contributions also include robust, conceivable and breakthrough technologies that will be viable and implementable by 2020.
Download or read book Reduced Kinetic Mechanisms for Applications in Combustion Systems written by Norbert Peters and published by Springer. This book was released on 2014-03-12 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: In general, combustion is a spatially three-dimensional, highly complex physi co-chemical process oftransient nature. Models are therefore needed that sim to such a degree that it becomes amenable plify a given combustion problem to theoretical or numerical analysis but that are not so restrictive as to distort the underlying physics or chemistry. In particular, in view of worldwide efforts to conserve energy and to control pollutant formation, models of combustion chemistry are needed that are sufficiently accurate to allow confident predic tions of flame structures. Reduced kinetic mechanisms, which are the topic of the present book, represent such combustion-chemistry models. Historically combustion chemistry was first described as a global one-step reaction in which fuel and oxidizer react to form a single product. Even when detailed mechanisms ofelementary reactions became available, empirical one step kinetic approximations were needed in order to make problems amenable to theoretical analysis. This situation began to change inthe early 1970s when computing facilities became more powerful and more widely available, thereby facilitating numerical analysis of relatively simple combustion problems, typi cally steady one-dimensional flames, with moderately detailed mechanisms of elementary reactions. However, even on the fastest and most powerful com puters available today, numerical simulations of, say, laminar, steady, three dimensional reacting flows with reasonably detailed and hence realistic ki netic mechanisms of elementary reactions are not possible.
Download or read book The Overall Reaction Concept in Premixed Laminar Steady State Flames I Stoichiometries written by T. P. Coffee and published by . This book was released on 1983 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion processes normally involve a large number of chemical species, related through a complicated reaction network and strongly interacting with the fluid flow and molecular transport. A common approach is to simplify the system by assuming a single overall or global reaction. In this paper, we will examine the adequacy of the overall reaction model for premixed, laminar, one-dimensional, steady-state flames. Our procedure is to first solve the equations governing the detailed chemistry model. The overall reaction rate parameters are then found from a least squares fit of the heat release profile. The overall reaction model equation can then be solved and the solution compared with the detailed model solution. This is done for three different flames over a range of stoichiometries. The single reaction model gives quite accurate results for flame speed. The temperature and heat release profiles are also generally accurate. The accuracy of the major species profiles varies from fair to good. However, the optimal overall kinetic parameters do vary with stoichiometry.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Diluents on Laminar Premixed Hydrogen Flames in Microgravity written by Li Qiao and published by . This book was released on 2007 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1997 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reacting Flows written by G. S. S. Ludford and published by American Mathematical Soc.. This book was released on 1986-12-31 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: These two volumes represent the culmination of the Special Year `84-'85 in Reacting Flows held at Cornell University. As the proceedings of the 1985 AMS/SIAM Summer Seminar in Applied Mathematics, the volumes focus on both mathematical and computational questions in combustion and chemical reactors. They are addressed to researchers and graduate students in the theory of reacting flows. Together they provide a sound basis and many incentives for future research, especially in computational aspects of reacting flows. Although the theory of reacting flows has developed rapidly, researchers in the two subareas of combustion and chemical reactors have not communicated. The main goal of this seminar was to synthesize the mathematical theory and bring it to the interface with large-scale computing. All of the papers have high research value, but the first five introductory lectures should be especially noted.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1985 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Methods for Partial Differential Equations written by Ivo Babushka and published by SIAM. This book was released on 1989-01-01 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Proceedings of the Workshop on Adaptive Computational Methods for Partial Differential Equations, Rensselaer Polytechnic Institute, October 13-15, 1988"--T.p. verso.
