亚临界雷诺数线性剪切流场中圆柱的气动升力特性研究  

Investigation of Aerodynamic Lift of a Circular Cylinder in Linear Shear Flows at Subcritical Reynolds Number

作　　者：王通[1] 曹曙阳[1] 周强[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《力学季刊》2011年第4期473-479,共7页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(50978202);上海市浦江人才计划(10PJ1409700)

摘　　要：通过风洞模型试验和数值模拟研究亚临界雷诺数范围内线性剪切流场中圆柱的气动升力特性。剪切流强度采用由速度梯度、圆柱半径及圆柱中心前方来流的平均速度所定义的无量纲剪切参数β来表示。在风洞模型试验中使用主动控制风洞来方便地生成线性剪切流。在数值模拟中采用基于动态Smagorinsky亚格子模型的大涡模拟方法。研究发现,在亚临界雷诺数线性剪切流中,驻点向高速侧漂移,驻点移动对圆柱气动力有明显的影响;圆柱周围的压力分布不对称,产生一个由高速侧向低速侧作用的升力。Aerodynamic lift of a circular cylinder in linear shear flows with its axis normal to the plane of the velocity shear profile is investigated at subcritical Reynolds number numerically and experimentally.The shear parameter β,which is based on the velocity gradient,cylinder diameter and upstream mean velocity at the center plane of the cylinder,is defined to represent intensity of shear flow.Linear shear flows are easily generated in actively controlled wind tunnels for model experiments.Large eddy simulation with dynamic Smagorinsky subgrid model is performed to supply physical explanations of the flow phenomenon.It is found that the stagnation point shifts to the high velocity side in linear shear flows at subcritical Reynolds number and it influences the aerodynamic force acting on a circular cylinder greatly.A mean lift occurs due to the asymmetrical distribution of pressure around the cylinder,and it acts from the high velocity side to low velocity side at subcritical Reynolds number.

关 键 词：圆柱绕流 剪切流 气动升力 风洞 大涡模拟 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程]