Numerical simulation of the mixing reaction flows in supersonic COIL

Mixing reaction flows in supersonic Chemical Oxygen Iodine Laser (COIL) were simulated by solving the Reynolds averaged Navier-Stokes equations and species continuity equations. Equations were solved using four-stage Runge-Kutta time-stepping scheme on structured viscous mesh. The simulation was carried out with AUSM+-up scheme employing the k-ε turbulence model. The method employed finite-rate chemistry and thermodynamic perfect gas properties for chemical reaction. The stiffness problem of chemical source was overcome by a relaxation iterative scheme. The I₂ mass fractions at the nozzle exit were presented. Results are in good agreement with the result of J.H. Miller et al in Computational Sciences Center of Excellence Air Vehicles Directorate concerning species concentrations.