SI2 Lighting Talk: GEM3D Project

We are developing a massively parallel, open-source computational fluid dynamics (CFD) software package (GEM3D) to study microscale atmospheric flows over complex terrain with super-fine numerical resolutions. Our package uses block structured Cartesian adaptive mesh refinement (AMR) methods to provide a practical, accurate method for geometrically modeling complex terrain and large-eddy simulation techniques with novel dynamic sub-grid scale models for physically modeling incompressible flows in complex terrain. In this poster, we report on some recent results from two sub-projects of the main project. The first is on the development of a highly scalable red-black binarized-octree for generating and managing the adaptively refined grids. The second is on the development of a scalable solver for the Pressure Poisson equation on multi-block Cartesian grids. We compare a custom non-overlapped domain decomposition technique with a more standard Krylov iterative method preconditioned with algebraic multigrid (AMG) for solving the discretized Poisson equation.