Simulation of chemically reacting flows in two-dimensional geometries

Abstract

Globally implicit solutions of the compressible Navier-Stokes equations including detailed chemistry in two space dimensions are performed by a method of lines. This has become possible by the recent development of numerical methods for the solution of stiff differential /algebraic equation systems together with the availability of fast computers with high storage capacity. Computations of ignition processes are performed by solving the corresponding conservation equations (i.e., conservation of total mass, momentum, energy, and species mass) using a detailed reaction mechanism for the ozone-oxygen system (consisting of six elementary reactions) and a multispecies transport model. Thermal ignition is simulated by an additional source term in the energy conservation equation. Spatial discretization on a two-dimensional grid that is adapted statically in two spatial directions leads to a differential/ algebraic equation system which is solved numerically by an implicit extrapolation method to overcome stiffness problems caused by the multiscale character of the system considered. Results are presented for the simulation of a laser-induced thermal ignition in an ozone-oxygen mixture in a cylindrical reaction vessel. However, the method can be generally applied to two-dimensional reactive flows in relatively simple geometries.