通孔柱体的流场特性研究  

Investigations on flow field characteristics of the through-hole cylinders

作　　者：高建国[1] 陈志华[1] 

机构地区：[1]南京理工大学瞬态物理实验室,南京210094

出　　处：《水动力学研究与进展（A辑）》2013年第6期754-760,共7页Chinese Journal of Hydrodynamics

摘　　要：当流体以一定速度绕经柱体时,会在物体表面产生分离,分离涡脱落产生尾部涡街,导致柱体阻力增加并产生振动,一定条件下还会造成柱体的解体。为了减小作用在柱体上的阻力并降低振动载荷,该文分别以通孔方柱与通孔圆柱为研究对象,通过大涡模拟数值计算了它们在Re?2.2×105时的流场,得到了相应的尾涡结构与升阻力系数曲线图。通过比较柱体通孔前后的流场发现,有通孔的柱体虽不能消除其尾涡的产生与脱落,但因通孔形成的涡系会降低柱体上下表面形成的分离涡尺寸,从而可有效减小柱体的阻力,同时还可降低其升力的脉动幅度。因此,柱体的通孔不失为一种简便易行的柱体减阻抑振被动控制方法。When the fluids pass a cylinder at certain velocity, the flow separation appears on the cylinder surface, and the separation induced vortexes will also shed from the wall surface to form typical vortex street. These phenomena can lead to the increase of cylinder drag as well as its vibration, and may also collapse the cylinder under certain conditions. In order to decrease the drag and vibration on the cylinders, the large eddy simulation is used to investigate numerically the flow field and force characteristics of both the through-hole circular and square cylinders at Re = 2.2×10^5, and obtain their corresponding vortex structures and the drag and lift coefficient curves. After comparing the calculated results of both circular and square cylinders with and without through-holes, the through-hole can not eliminate the vortex shedding, but the vortexes induced by the hole can decrease the size of vortexes shedding from the cylinder, which results in decreasing drag and vibrating amplitude of lift. Therefore, the through-hole of a cylinder can be considered as a simple and practical passive control method of reducing the cylinder drag and vibration.

关 键 词：柱体绕流 旋涡脱落 通孔 数值模拟 升阻力 

分 类 号：O352[理学—流体力学]