Direct Numerical Simulation and Large Eddy Simulation on a Turbulent Wall-Bounded Flow Using Lattice Boltzmann Method and Multiple GPUs
State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, 28 xianning west road, Xi’an 710049, China
Mathematical Problems in Engineering, 2014
@article{kobayashi2014direct,
title={Direct Numerical Simulation and Large Eddy Simulation on a Turbulent Wall-Bounded Flow Using Lattice Boltzmann Method and Multiple GPUs},
author={KOBAYASHI, Hiromichi and AOKI, Takayuki},
year={2014}
}
Direct numerical simulation (DNS) and large eddy simulation (LES) were performed on the wall-bounded flow at Re_tau = 180 using lattice Boltzmann method (LBM) and multiple Graphic Processing Units (GPUs). In the DNS, 8 K20M GPUs were adopted. The maximum number of meshes is 6.7×10^7, which results in the non-dimensional mesh size of Delta+=1.41 for the whole solution domain. It took 24 hours for GPU-LBM solver to simulate 3×10^6 LBM steps. The aspect ratio of resolution domain was tested to obtain accurate results for DNS. As a result, both the mean velocity and turbulent variables, such as Reynolds stress and velocity fluctuations, perfectly agree with the results of Moser et al [5] when the aspect ratios in streamwise and spanwise directions are 8 and 2 respectively. As for the LES, the local grid refinement technique was tested and then used. Using 1.76×10^6 grids and Smagorinsky const (Cs) =0.13, good results were obtained. The ability and validity of LBM on simulating turbulent flow were verified.
February 16, 2014 by hgpu