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本文采用多重直接力 内嵌边界法计算流体与粗糙壁面之间的相互作用力,直接数值模拟了粗糙壁面上湍流边界层的流动状况.粗糙壁面则通过流向和展向分别叠加正弦函数的方法产生.研究发现,峰值较大的位置优先诱导产生出涡结构,并且加大了涡结构的倾斜角度.此外,较大峰值处的粗糙度所产生出的“喷出”和“扫入”事件更加强烈,其对外层的作用范围也就更大.同时粗糙壁面的峰值大小对于雷诺应力的输运也起着至关重要的作用.“,”A direct numerical simulation was performed to investigate turbulent flow over a rough wall using a combined between multiple direct forces and inner boundary method.The rough wall was generated by the superposition of spanwise and streamwise sinusoidal functions.The simulation showed that vortex structures were induced preferentially at the locations of lager peak and the inclination degree of vortex structure was also increased.In addition,the lager peak produced fiercer incident of “ejection” and “sweep” and their effects extended larger.The size of rough wall peak also had significant effects on the transportation of Reynolds stresses.