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基于离散涡方法求得的非定常、不稳定流场和颗粒的Lagrangian运动方程,数值计算了四种St数下的泥沙粒子在圆柱绕流场中的运动.计算结果证明了颗粒运动与流体旋涡存在着明确的相关结构:在钝体(圆柱)表面附着泥沙,当流体流过钝体时产生具有剧烈分离的不稳定流动,带动钝体表面泥沙起浮.对于小St数(0.15~0.59)与中等St数(1.33~2.36)的泥沙颗粒被流体旋涡所带起,井被卷入流体旋涡结构内,被卷入流体旋涡结构内的泥沙颗粒在运动过程中始终分布于旋涡区,即在旋涡区聚集.“,”The present research on the influence of vortex on particle motion in liquid-particle twophase flow was carried out numerically. On each time step, the unsteady and/or unstable flow field is evaluated with the Vortex Method; Based upon the obtained flow field, the Lagrangian equation for particle motion is then solved simultaneously. The numerical result proves that the definite interrelated structure exists between the particle motion and the fluid vortices: Unstable flow with massive separation is caused while fluid passes a blunt,the separated fluid flow picks up the sediment adhering to the surface of the blunt. For small values of St(0.15~0.59) and intermediate values of St(1.33~2.36), solid particles (sediment) are drawn into the vortex structures. The solid particles drawn into the vortex structures always distribute in the vortex regions, i.e. the particles accumulate in the vortex regions.