Bluff body flow simulation using lattice Boltzmann equation with multiple relaxation time

Numerical simulations using multiple-relaxation-time lattice Boltzmann model (MRT-LBM) are carried out for a long slender rigid circular cylinder in a cross flow to examine three-dimensional wake effect on the flow-induced forces. A mesh refinement technique is applied in the MRT-LBM calculation. The aim is to assess the validity and efficiency of the MRT-LBM model in three-dimensional calculation. In order to simulate the practical situation correctly, wall boundary conditions are specified at both ends of the cylinder. The aspect ratio of the slender cylinder is 16. The calculation is compared with results obtained from a finite volume method (FVM) and a lattice BGK model [Bhatnagar PL, Gross EP, Krook M. A model for collision processes in gases. 1. Small amplitude processes in charged and neutral one-component systems. Phys Rev 1954;94:511–25] with refined grid. Good agreement is obtained. It is found that the MRT-LBM is more efficient and faster in three-dimensional calculations.