Numerical Methods in Laminar Flame Propagation
Title | Numerical Methods in Laminar Flame Propagation PDF eBook |
Author | Norbert Peters |
Publisher | Vieweg+teubner Verlag |
Pages | 218 |
Release | 1982 |
Genre | Mathematics |
ISBN |
This volume collects the results of a workshop held at Aachen, West-Germany, Oct. 12 - Oct. 14, 1981. The purpose in bringing together scientists actively working in the field of numerical methods in flame propagation was two-fold: 1. To confront them with recent results obtained by large ac tivation-energy asymptotics and to check these numerically. 2. To compare different numerical codes and different trans port models for flat flame calculations with complex che mistry. Two test problems were formulated by the editors to meet these objectives. Test problem A was an unsteady propagating flat flame with one-step chemistry and Lewis number different from unity while test problem B was the steady, stoichiometric hy drogen-air flame with prescribed complex chemistry. The parti cipants were asked to solve one or both test problems and to present recent work of their own choice at the meeting. The results of the numerical calculations of test problem A are challenging just as much for scientists employing numerical me thods as for those devoted to large activation-energy asympto tics: Satisfactory agreement between the five different groups were obtained only for two out of six cases, those with Lewis number Le equal to one. The very strong oscillations that oc cur at Le = 2 and a nondimensional activation energy of 20 were accurately resolved only by one group. This case is par ticular interesting because the asymptotic theory so far pre dicts instability but not oscillations.
Reacting Flows
Title | Reacting Flows PDF eBook |
Author | G. S. S. Ludford |
Publisher | American Mathematical Soc. |
Pages | 538 |
Release | 1986-12-31 |
Genre | Mathematics |
ISBN | 9780821896921 |
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.
Variational Methods for Free Surface Interfaces
Title | Variational Methods for Free Surface Interfaces PDF eBook |
Author | Paul Concus |
Publisher | Springer Science & Business Media |
Pages | 201 |
Release | 2012-12-06 |
Genre | Science |
ISBN | 1461246563 |
Vallombrosa Center was host during the week September 7-12, 1985 to about 40 mathematicians, physical scientists, and engineers, who share a common interest in free surface phenomena. This volume includes a selection of contributions by participants and also a few papers by interested scientists who were unable to attend in person. Although a proceedings volume cannot recapture entirely the stimulus of personal interaction that ultimately is the best justification for such a gathering, we do offer what we hope is a representative sampling of the contributions, indicating something of the varied and interrelated ways with which these classical but largely unsettled questions are currently being attacked. For the participants, and also for other specialists, the 23 papers that follow should help to establish and to maintain the new ideas and insights that were presented, as active working tools. Much of the material will certainly be of interest also for a broader audience, as it impinges and overlaps with varying directions of scientific development. On behalf of the organizing committee, we thank the speakers for excellent, well-prepared lectures. Additionally, the many lively informal discussions did much to contribute to the success of the conference.
The Theory of Steady Laminar Spherical Flame Propagation
Title | The Theory of Steady Laminar Spherical Flame Propagation PDF eBook |
Author | D. B. Spalding |
Publisher | |
Pages | |
Release | 1952 |
Genre | |
ISBN |
Numerical Aspects of Laminar Flame Simulation
Title | Numerical Aspects of Laminar Flame Simulation PDF eBook |
Author | Bas van't Hof |
Publisher | |
Pages | 152 |
Release | 1998 |
Genre | Combustion |
ISBN | 9789038606415 |
Computation of Steady and Unsteady Laminar Flames
Title | Computation of Steady and Unsteady Laminar Flames PDF eBook |
Author | National Aeronautics and Space Administration (NASA) |
Publisher | Createspace Independent Publishing Platform |
Pages | 36 |
Release | 2018-06-15 |
Genre | |
ISBN | 9781721193950 |
In this paper we describe the numerical analysis underlying our efforts to develop an accurate and reliable code for simulating flame propagation using complex physical and chemical models. We discuss our spatial and temporal discretization schemes, which in our current implementations range in order from two to six. In space we use staggered meshes to define discrete divergence and gradient operators, allowing us to approximate complex diffusion operators while maintaining ellipticity. Our temporal discretization is based on the use of preconditioning to produce a highly efficient linearly implicit method with good stability properties. High order for time accurate simulations is obtained through the use of extrapolation or deferred correction procedures. We also discuss our techniques for computing stationary flames. The primary issue here is the automatic generation of initial approximations for the application of Newton's method. We use a novel time-stepping procedure, which allows the dynamic updating of the flame speed and forces the flame front towards a specified location. Numerical experiments are presented, primarily for the stationary flame problem. These illustrate the reliability of our techniques, and the dependence of the results on various code parameters. Hagstrom, Thomas and Radhakrishnan, Krishnan and Zhou, Ruhai Glenn Research Center NASA/CR-1999-209305, NAS 1.26:209305, AIAA Paper 98-3246, ICOMP-99-07, E-11826
Reduced Kinetic Mechanisms for Applications in Combustion Systems
Title | Reduced Kinetic Mechanisms for Applications in Combustion Systems PDF eBook |
Author | Norbert Peters |
Publisher | Springer Science & Business Media |
Pages | 364 |
Release | 2008-09-11 |
Genre | Science |
ISBN | 3540475435 |
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.