采用RANS和LES相结合的数值计算方法,系统分析了给定条件下二维平板横置小肋对湍流摩擦阻力的影响.并开展了小肋外形及布置参数的优化研究.使用RANS方法计算平板阻力,而LES方法则着重分析流场变化过程,以分析减阻机理.通过对不同外形和参数小肋的CFD计算结果的比较分析,得到了该计算条件下减阻效果最佳的小肋参数,与光滑平板对比,最大减阻近4％.通过对流场的分析可以看到,横置小肋之间产生涡柱,改变了流体与平板的作用方式及近壁速度剖面,进而可以降低摩擦阻力.研究为进一步分析横置小肋在更宽速度和雷诺数范围内的有效性及开展全面的参数优化研究提供了基础.%The drag reduction effects of laterally configured riblets on flat plate are systematically studied using a combination of RANS and LES methods. The effects of different riblet shapes, geometry parameters and number of riblets are analyzed and optimized. The RANS code is used to calculate the drag values while the LES is used to investigate the detailed flow patterns in the boundary layers due to the presence of the riblets. Optimal parameters are obtained using response surface method based on CFD results. It can be seen from the numerical study that 4% drag reduction can be achieved comparing to flat plate. This is primarily caused by the reduction in turbulent frictions drag. The research provides a basis for further research on turbulent drag reduction using lateral riblets.
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