Simulation of spatial high speed mixing layers using LES

• The simulation of a spatial mixing layer is performed using LES.
• A detailed grid independence study is carried out.
• The growth rate is measured and compared with the experiments.
• Removal of the velocity deficit is studied.
• Study of attainment of self similarity is presented.

The present paper is concerned with the simulation of the spatial supersonic mixing layer using large eddy simulation, with PISO algorithm, using one equation eddy viscosity model for sub grid scale stress modelling, a fourth order spatial and a second order temporal scheme. The size of the domain is of a similar to that of experiments, and encompases the splitter plate effect. The calculations are ascertained to be grid independent for grid sizes of 1200×260,800×2001200×260,800×200 and 600×160600×160. The calculations are shown to match the experiments of Goebel and Dutton (1990) [1] and Papamoschou and Roshko (1988) [2] reasonably well, and are able to capture the effect of the reduced growth rate with increased McMc within the tolerance of experiments. The simulations are used further to study the removal of velocity deficit and the attainment of self similarity with increasing McMc.