二维不可压流中的一种边界元方法

BOUNDARY ELEMENT METHOD IN TWO-DIMENSIONAL INCOMPRESSIBLE FLOW

本文用矢量格林公式把连续方程变换成积分方程。对于位流问题,涡只存在于边界层内,可以导出边界层外缘处切向速度等于-x,x为涡强。如果假定物面上速度为0,则边界层中线上的切向速度为-1/2x。然后,离散积分方程,解出X,继而求得边界层外缘处速度分布。

The paper discusses applications of boundary element method in the solution of problems involving 2D incompressible flow. The continuity equation is translated into an integral equation by the vector Green formula. For potential flow, vorticity only distributes in the interior of boundary layer, then the tangential velocity at the outer edge of the boundary layer equals-χ, where χ is the strength of the vortex. If no-slip condition on the solid surface is assumed, the tangential velocity on the middle line of the boundary layer equals-0.5χ. The intergral equation is numerically solved, the strength of the vortex obtained, and distribution of the velocity is found.