비정렬 격자를 이용한 LES 기법 개발

DEVELOPMENT OF A LARGE EDDY SIMULATION METHOD ON UNSTRUCTURED MESHES

A large eddy simulation with explicit filters on unstructured mesh is presented. Two explicit filters are adopted for reducing the aliasing error of the nonlinear convective term and measuring the level of subgrid scale velocity fluctuation, respectively. The developed subgrid scale model is basically eddy viscosity model which depends on the explicitly filtered fields and needs no additional ad hoc wall treatment such as van Driest damping function. As a validation problem, the flows around a sphere at several Reynolds numbers, including laminar and turbulent regimes, are calculated and compared to experimental data and numerical results in the literature.