Spectral Large-Eddy Simulation/Filtered Mass Density Function (LES/FMDF) for Simulation of Turbulent Combustion Interaction in High Speed Flow on Unstructured Grids

摘要

This report was developed under a STTR contract for topic OSD10-T001, The goal of this project is to develop advanced large-eddy simulation (LES) software based on a 'high-order spectral element method on unstructured grid' for simulation of high speed turbulent reacting flows. The combustion modeling is via the accurate, pdf-based, 'filtered mass density function (FMDF)' method. In FMDF, the turbulence combustion interaction term is naturally closed and does not require additional modeling. Shocks are captured with the entropy viscosity (EV) method that provides additional viscosity at the location of the shock to stabilize the solution but preserves the high order of the solution away from the shock. Explicit (spectral) filtering is used to model the filtered small scales in LES. This method has a negligible computational overhead and can be implemented independently of the geometry or the size of the grid. The results provided in this Phase I report demonstrate the proof of concept for these methods.