1 Multi-Scale Turbulence Model in Simulation of Supersonic Crossflow Part 2: Inclined Injection

The multi-scale turbulence approach is useful in predicting mean flows in problems containing complex turbulent structures that are otherwise unattainable using standard Reynolds-averaged Navier-Stokes models. In crossflow simulations using the multi-scale turbulence approach, modifying the sub-filter turbulent mass diffusion based on the resolved field was useful in simulation of normal injection with coarser grids. Inclined injection angles are commonly evaluated for improved mixing performance; this work is therefore aimed at assessing the multi-scale approach with inclined injection in supersonic crossflow. Reynolds-averaged Navier-Stokes and multi-scale without the adaptive turbulent Schmidt number approach are compared to experimental fuel concentration measurements. Unlike previous normal injection results, multi-scale alone did not improve the results significantly even with a grid of nearly 30 million cells. Turbulent fluctuations of the normal and inclined injections are compared showing vortical structures that are scattered and of higher frequency in the latter case. The adaptive approach is then used with the same grid in the inclined case in order to improve the prediction of turbulent mixing. Results with the adaptive turbulent Schmidt number approach are superior to both RAN