本文采用大涡模拟对平板前缘分离在周期性来流激励作用下的流动结构进行了数值研究.将计算得到的结果与实验数据进行了对比.在此基础上,对涡量等值面和Q准则可视化手段进行了比较.通过研究不同外部周期性激励频率抑制分离的效果,讨论了有效外部扰动频率与分离区域特征频率的关系.结果显示,外部频率为∫shear、(∫),shed、1/2(∫)ahear时分离抑制明显,其中1/2(∫)shear效果最佳.当分离区域显著减小时,流动具有明显的周期性;当在外部扰动作用下的分离抑制效果很弱时,外部扰动无法直接在分离区域中促成对应尺度的涡生成.
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