Parallel Computational Fluid Dynamics, Turin, Italy, 25 - 27 May 2022, pp.1
We present an efficient nodal discontinuous Galerkin method for approximating nearly incompressible flows using the Lattice-Boltzmann equations on unstructured triangular and quadrilateral meshes. The equations are discretized in time using semi-analytic time integration scheme enabling higher CFL numbers in stiff regimes. Performance portability of the solver on different platforms is achieved by using the open concurrent compute abstraction, OCCA. We optimize the performance of the most time-consuming kernels by tuning the fine-grain parallelism, memory utilization, and maximizing bandwidth. Accuracy and performance of the method are tested using distinct numerical cases including Couette flow, isothermal vortex and flow around square cylinder test cases. Preliminary numerical results confirm we achieve the design order accuracy in time and space.