用Lattice Boltzmann方法计算矩形柱的绕流问题

Lattice Boltzmann Simulation of Flow Past a Rectangular Cylinder

采用二维9速度Lattice Boltzmann模型,数值模拟流体流过矩形截面柱体的绕流问题.在边界处,采用二阶精度的插值边界处理方法,计算了流动的Strouhal数及柱体受到的升力和阻力系数,给出了流场的流线和等涡线图.使来流方向与矩形柱的长边方向平行,计算结果表明,改变矩形的长/宽比,流场的Strouhal数随长/宽比呈线性变化.

A two-dimensional nine-velocity Lattice Boltzmann model was employed to simulate the tlow past a rectangular elongated cylinder numerically. The second-order interpolation scheme was used for the boundary treatment. The Strouhal number, the drag coefficient and lift coefficient were calculated. The streamlines and the vorticity contours were presented. Under varying the length/width ratio of the rectangular, and keeping the inlet velocity to be parallel to the length side of the rectangular cylinder, numerical results show that the Strouhal number varies linearly with the length/width ratio.