Abstract: By comparing and analyzing the numerical simulation results with the experimental data,the accuracy of numerical simulation is verified. By changing the width of flume model to change the blockage ratio,the wake characteristics is analyzed under the condition of the blockage ratio of 9.8%,14.7% and 29.5% respectively using STAR-CCM+. The results show that variation of blocking ratio will not only change the fluid velocity outside the sweep area,but also affect the recovery in the far wake,and also affect the rotation and turbulent kinetic energy distribution. However,with the increase of the flume width,the blockage ratio decreases,the influence on wake characteristics is gradually weakened.