Geometry, mesh and adaptivity for high reynolds number viscous flow simulations

点击翻译按钮获取中文摘要

While numerical methods and CFD have progressed tremendously in the last twenty years, their applicability to highly complex industrial problems is still limited by the efforts and time required by engineers to accurately model and discretize computational domains. The proposed research aims to help reduce the time required by engineers to prepare models through the development of innovative geometry and mesh manipulation methods addressing the needs of simulation. This research program also aims to enhance the accuracy and precision of high Reynolds number turbulent computational fluid dynamics (CFD) analysis used for the design of complex three dimensional mechanical devices, and particularly hydraulic turbomachinery. This proposal will investi- gate innovative approaches for 1) geometric modeling, 2) mesh generation and 3) a posteriori mesh adaptation in the context of CFD simulations of viscous, turbulent incompressible flows using finite volume solvers. The proposed research on geometric modeling aims to advance computational domain representation and manipula- tion. This research will investigate combining implicit and standard parametric boundary representation of a computational domain in order to benefit from complementary advantages of each representation for domain discretization and shape manipulation. Surface reparameterization techniques will be particularly investigated, through the construction of surrogate surfaces using alternate representations in support to subsequent domain discretization operations. Research on mesh generation will focus on the a priori construction of adequate el- ement size and shape control functions for the efficient generation of high quality computational grids. Control of element shape and size in the course of unstructured mesh generation is the source of many difficulties in the context of industrial applications. The proposed research will aim to identify efficient size specification approaches applicable to meshes of mixed element types. Themes related to a posteriori mesh adaptation include a posteriori error estimation for incompressible turbulent Navier-Stokes finite volume solutions, the combination of several variables to steer adaptation and convergence of mesh adaptation algorithms.