中文摘要：

为研究非光滑圆柱绕流减阻性能,采用SST k-ω湍流模型对亚临界雷诺数R_e=40 000下凹坑圆柱绕流进行数值模拟及减阻性能研究。对凹坑深度、内部形状、分布形式进行了结构参数敏感性分析,研究各参数对凹坑圆柱绕流减阻性能的影响规律。结果表明：凹坑圆柱具有较好的绕流减阻效果;阻力系数、升力系数均随凹坑深度增加呈先减小后增大的变化趋势,且在h=0.015D时,凹坑圆柱绕流具有最佳减阻效果;圆柱形凹坑圆柱平均阻力系数为0.923,球面形凹坑圆柱平均阻力系数为0.94;菱形分布凹坑织构的圆柱绕流阻力系数平均值为0.923,矩形情况为0.973。

英文摘要：

In order to study the drag reduction performance of non-smooth circular cylinder,the SST k-ω turbulence model was been used to simulate the flow around a circular cylinder and studied the drag reduction performance of a circular cylinder at the subcritical Reynolds number R_e= 40 000. The sensitivity analysis of dimples ＇ structure parameters,which include the depth,the inner shape and the distribution of dimples is carried out to study the influence of various parameters on the drag reduction of the flow around a circular cylinder. The results show that the circular cylinder with dimples has a good effect on drag reduction. Drag coefficient and lift coefficient decrease with the increasement of dimple depth first and then decrease increase.Moreover,the circular cylinder with dimples has the best drag reduction effect when h = 0. 015 D. The average drag coefficient of the circular cylinder with cylindrical dimples is 0. 923 while the average drag coefficient of the circular cylinder with spherical dimples is 0. 94. The average drag coefficient of the circular cylinder with dimples by diamond distribution is 0. 923 while the average drag coefficient of the circular cylinder with dimples by rectangle is 0. 973.