TOWARDS FFT-BASED DIRECT NUMERICAL SIMULATIONS OF TURBULENT FLOWS ON A GPU

Abstract

The accurate simulation of turbulence and the implementation of corresponding turbulence models are both critical to the understanding of the complex physics behind turbulent flows in a variety of science and engineering applications. Despite the tremendous increase in the computing power of central processing units (CPUs), direct numerical simulation of highly turbulent flows is still not feasible due to the need for resolving the smallest length scale, and today's CPUs cannot keep pace with demand. The recent development of graphics processing units (GPU) has led to the general improvement in the performance of various algorithms. This study investigates the applicability of GPU technology in the context of fast-Fourier transform (FFT)-based pseudo-spectral methods for DNS of turbulent flows for the Taylor–Green vortex problem. They are implemented on a single GPU and a speedup of unto 31x is obtained in comparison to a single CPU.