Operator splitting methods for the computation of reacting flows
Abstract
Chemical kinetic modeling must give as accurate a description as possible of the multistep, multicomponent chemistry that is typically associated with most real combusting systems. Once the governing equations are established and a chemical kinetic scheme is postulated, however, a major obstacle to attaining a numerical solution to the problem arises. This is the stiffness problem, and it is caused by the wide range of time scales associated with reactive collisions between molecules and/or atoms. A general approach, developed with particular reference to elliptic flows, to overcoming the stiffness problem is outlined. A way of splitting the species conservation equation by introducing a new chemical splitting parameter is described. For the case of elliptic flow with a unimolecular reversible chemical reaction, a convergence analysis provides insight into the conditions under which a converged solution will be obtained. The existence of an optimum value of the chemical splitting parameter is seen as suggesting the possibility of accelerating convergence. Calculated results from test problems involving linear and nonlinear chemical kinetic models are presented.
 Publication:

Computers and Fluids
 Pub Date:
 1983
 Bibcode:
 1983CF.....11...95G
 Keywords:

 Chemical Reactions;
 Combustible Flow;
 Computational Fluid Dynamics;
 Operators (Mathematics);
 Reaction Kinetics;
 Conservation Equations;
 Convergence;
 Mathematical Models;
 Molecular Collisions;
 Splitting;
 Stiffness;
 Fluid Mechanics and Heat Transfer