快速涡方法中涡片扩散的新算法（英文）

A New Scheme for Vortex Sheet Diffusion in Fast Vortex Methods

在Ploumhans粘性涡方法的基础上,文章研究了一种用于三维非定常流场计算的快速涡方法。同时根据壁面无滑移边界条件,提出了一种新的涡片扩散方法。通过将涡量分配给流场内的涡粒子,模拟了物面产生的涡量扩散到流体中的过程。为了降低计算量并保证较高的计算精度,采用了自适应快速多极方法进行速度及速度梯度的计算。该方法应用于球突然启动瞬态流动数值模拟,通过与实验数据及其他数值计算结果进行比较,验证了方法的可行性。

Following Ploumhans,a fast vortex method was developed for the analyses of three-dimensional unsteady flow.A new diffusion method is proposed for the vorticity creation close to a 3D body surface,in which a number of vortex particles are introduced into the flow field to satisfy the nonslip boundary condition on the boundary.An adaptive Fast Multipole Method(FMM)is used for velocity and its gradient computing to achieve high accuracy at a reasonable cost.The new scheme is applied to the simulations of starting flow around a sphere at Re=300 and 500 for investigating the feasibility.