Lattice Boltzmann Simulation of Flow past a Sphere up to Reynolds Number of 300

摘要

In this paper, lattice Boltzmann method (LBM) is used to numerically simulate the flow past a sphere at low Reynolds numbers (Re) of 100, 150, 200, 250 and 300, respectively. For Re below 200, the flow is separated, steady, axisymmetric and topologically similar, and the wake is laminar; for Re between 210 and 270, steady and planar-symmetric flow is observed; and for Re between 280 and 375, the flow becomes unsteady but planar-symmetry is maintained. The above Reynolds numbers are chosen to stand for the above these different flow regimes. To get better accuracy, a local mesh refinement technique is adopted. The calculation has been validated against measurement and other available numerical simulation. The present calculation compares well with available results in mean drag coefficient, separation angle, and vortex position.