Abstract
In this research, Poiseuille turbulent square duct flow simulations with single-relaxation time lattice Boltzmann method (SRT LBM) and entropic lattice Boltzmann method (ELBM) on multi-GPU are studied. Taking the advantage of GPU, computation times can be shortened, thus fully developed turbulent flow is achieved easily and a fine mesh is able to be employed. Although the LBM with D3Q27 model is needed essentially for turbulent duct flow explored by Kang and Hassan in 2013, SRT LBM and ELBM with different models (i.e.D3Q15, D3Q19 and D3Q27) are still adopted to investigate the influence of D3Q15 and D3Q19 in laminar duct flow at friction Reynolds number Reτ = 20 and in turbulent duct flow at Reτ = 360. To simulate turbulent duct flow with LES model, Smagorinsky subgrid-scale model with Van Direct damping function is utilized. And, the effect of simulations with and without LES model are discussed in detail. Meanwhile, turbulent duct flow simulations at Reτ= 360 in different grid sizes of 540 × 90 × 90, 552 × 138 × 138 and 1080 × 180 × 180 are conducted as grid sensitivity test to obtain optimal mesh size related Reτ. Then, turbulent duct flow simulations with D3Q27 SRT LBM at Reτ = 600 are demonstrated. From physical phenomena viewpoint, turbulent structure is investigated in the turbulent duct flow at Reτ = 360. In addition, parallel performance of multi-GPU cluster is also discussed.