摘要
利用分块联合求解的思想 ,在贴体正交曲线网格上 ,用k ε双方程模型和简化的SOLA方法对圆柱面上微小后向台阶的紊流绕流场进行了数值研究 ,探讨了台阶几何高度、安装位置、绕流雷诺数对流场的影响及圆柱面上微小后向台阶扰流减阻的物理机制。数值分析发现 ,对圆柱面上安装的微小后向台阶 ,在宽广的雷诺数范围内 ,存在着一个“有效再附区域” ,从后向台阶处形成的分离流动若能在有效再附区域内形成流动再附 ,则该再附流动在圆柱面上的分离点将落在常规分离点的下游 ,从而导致圆柱绕流阻力的减小。这种分离点的后移 。
Results of numerical simulation for viscous incompressible turbulent flow field over a tiny rearward facing step on circular cylinder are presented.The Domain Subdividing and Matching method and the Simplified SOLA solution are engaged in the simulation. The effects of the step's height,installed position and Reynolds number on the flow field are obtained and discussed. The results show that, if the rearward facing step is installed on the cylinder surface at a suitable point, a reattached boundary layer will be produced at the downstream of the step lagged in a small distance on the cylinder s surface and will re separate from the cylinder s surface.The reattachment point and the re separated point will exchange as the step's height and installed point exchanging.There is an effective reattachment region. If the fluid flow separated from the sharp edge of the rearward step reattaches in the effective region, the re separated point will occur at the downstream of the cross section of the cylinder and the drag will be reduced. This pattern is not directly connected with the flow in laminar nor in turbulent.[WT5HZ]
出处
《重庆大学学报（自然科学版）》
CAS
CSCD
2000年第2期87-91,共5页
Journal of Chongqing University
基金
重庆优秀中青年科技专家基金资助项目!( 95 0 0 2 2 )
关键词
不可压缩流动
数值模拟
紊流流动
绕流场
viscous incompressible flow
numerical simulation
turbulent flow
separated flow
boundary layer
