不同间隔比下串列双梯形柱绕流特性的数值模拟  

Numerical Simulation of Flow Characteristics Around Tandem Double Trapezoidal Columns with Different Spacing Ratios

作　　者：程文明[1] 李杭飞 杜润[1] 王玉璞[1] 王书标 CHENG Wenming;LI Hangfei;DU Run;WANG Yupu;WANG Shubiao(School of Mechanical Engineering,Southwest Jiaotong University//Sichuan Key Laboratory of Technology and Equipment of Rail Transit Operation and Maintenance,Chengdu 610031,Sichuan,China)

机构地区：[1]西南交通大学机械工程学院//轨道交通运维技术与装备四川省重点实验室,四川成都610031

出　　处：《华南理工大学学报（自然科学版）》2021年第12期61-68,共8页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51675450)。

摘　　要：基于计算流体软件Fluent,采用Realizable k-ε湍流模型,对雷诺数Re=6.6×105下不同间隔比的串列双梯形柱绕流特性进行仿真分析;选取间隔比S*在0.5~6之间的7种不同取值,对双梯形柱气动特性系数、涡量图和流线图进行阐述。结果表明:串列梯形柱绕流特性与串列圆柱和矩形柱相似,在不同间隔比下存在3种绕流模式,即模式Ⅰ(屏蔽区)、模式Ⅱ(再附区)和模式Ⅲ(撞击区);各模式间存在临界间隔比S*cr,在间隔比S*<1处双梯形柱间产生屏蔽区,1<S*<3时上游梯形柱尾迹在下游梯形柱上下表面产生再附,S*>3时双梯形柱形成各自的涡旋脱落轨迹,下游尾迹涡旋随间隔比的增加由单列交替脱落(模式Ⅰ)过渡为双列脱落(模式Ⅱ、模式Ⅲ);受上游梯形柱尾迹影响,模式Ⅰ下结构稳定性和气动特性参数较其他模式更好。With the computational fluid software Fluent,the Realizable k-εturbulence model was used to simulate the flow characteristics of the tandem double trapezoidal column with different spacing ratios under the Reynolds number Re=6.6×10^(5).Seven kinds of interval ratios with interval ratio S*between 0.5~6 were selected to explain the aerodynamic coefficient,vorticity diagram and streamline diagram of the double trapezoidal column.The results show that the flow characteristics of tandem trapezoidal columns are similar to tandem cylinders and rectangular columns,and there are three modes of flow with different spacing ratios:ModeⅠ(Shieldeing regime),ModeⅡ(Reattachment regime)and ModeⅢ(impinging regime).There is critical interval ratio S*cr between modes.A shielding area is generated between the double trapezoidal columns at the interval ratio of S*<1;the upstream trapezoidal column trails reattach to the upper and lower surfaces of the downstream trapezoidal column at 1<S*<3.The double trapezoidal column forms its own vortex shedding at S*<3,and the vortex of the downstream changes from a single row of alternating drop(ModeⅠ)to a double row of drop(ModeⅡ,ModeⅢ)with the increase of the interval ratio.Affected by the upstream trapezoidal column trails,the structural stability and aerodynamic parameters of ModeⅠare better than those of other modes.

关 键 词：串列梯形柱 间隔比 雷诺数 绕流特性 涡旋脱落 结构稳定性 

分 类 号：TH213.5[机械工程—机械制造及自动化]