LAGRANGIAN SIMULATION OF A REACTING MIXING LAYER AT LOW HEAT RELEASE

The vortex-scalar element method, a Lagrangian scheme which utilizes vortex elements to discretize the vorticity field and scalar elements to represent species or temperature fields, is utilized in the numerical simulation of a two-dimensional, non-premixed, incompressible reacting mixing layer at high Reynolds and Peclet numbers without resorting to turbulence models. In non-reacting flow, conserved scalar mean and fluctuation profiles show good agreement with experimental measurements. In reacting flow, results indicate that for the temperature-independent kinetics, the chemical reaction starts immediately downstream of the splitter plate, where mixing starts. With Arrhenius kinetics, ignition delay, which depends on the reactant's temperature, is observed. In this case, strong stretch along the braids may cause local quenching due to the temperature drop associated with large diffusive fluxes. Harmonic forcing changes the layer structure and the mixing rates in accordance with experimental results.