GPU-Accelerated Algebraic Multigrid for Applied CFD

Current trends in high performance computing (HPC) are advancing towards the use of graphics processing units (GPUs) to achieve speed-ups for linear algebra matrix operations that are common in applied computational fluid dynamics (CFD) solvers. In recent years GPUs have been developed exclusively for computational tasks as massively-parallel co-processors to x86-based CPUs, and provides new HPC opportunities for industry application of CFD software from commercial vendors who mostly deploy implicit sparse iterative solvers.In order to speed the adoption of GPUs for applied CFD, NVIDIA has developed a library of multi-level linear solvers that include algebraic multigrid (AMG) and others that are common to commercial CFD software. This paper examines the parallelization of all phases of AMG including hierarchy construction and ILU factorization and solve, and provides examples of deployment in the coupled incompressible solver in ANSYS Fluent 14.5 released in Dec 2012. Future work will be discussed on the open research in the area of algebraic multigrid on massively parallel processors.