均匀吸气控制下后台阶流动的数值模拟  

Numerical simulation of a backward-facing step flow controlled by steady suction

作　　者：郑朝荣[1] 张耀春[1] 张建胜[2] 张文元[1] 

机构地区：[1]哈尔滨工业大学土木工程学院,哈尔滨150090 [2]浙江工业大学建筑工程学院,杭州310014

出　　处：《哈尔滨工业大学学报》2012年第4期23-27,共5页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(51108142);中国博士后基金(2011M500672);浙江省自然科学基金(Y1110128)

摘　　要：为检验本文数值方法及其求解策略模拟均匀吸气控制下钝体绕流的可行性,分别采用基于LES(large eddy simulation)方法的DKEM(dynamic kinetic energy subgrid-scale model)模型和基于RANS(ReynoldsAveraged Navier-Stokes)方法的SST(shear stress transport)k-ω模型对均匀吸气控制下三维后台阶(backward-facing step,BFS)的流动分离和再附进行了数值模拟.比较了数值模拟和实验所得的平均风压系数分布和再附长度,结果表明:LES方法在本文精细网格下能得到较精确的预测结果;不同流量系数CQ的吸气控制均能较显著地减小后台阶流动的环绕区范围和再附长度,改善台阶后的流场结构;随着CQ绝对值的增加,吸气控制效果逐渐显著.To verify the feasibility of the numerical methods and solution strategies for simulating the flows around bluff bodies controlled by steady suction, the separation and reattachment over a suction-controlled backward-facing step （BFS） flow is numerically investigated using the dynamic kinetic energy subgrid-seale model （DKEM） model based on the large eddy simulation （LES） method and the SST -to model based on the Reynolds averaged Navier-Stokes （RANS） method, respectively. Comparisons of the mean pressure coefficient and reattachment length between the numerical simulations and the existed experiment are also conducted to prove the validity. The results indicate that the LES can acquire exact results under the refined grid adopted in the paper. Suction control with any suction flow coefficient CQ can reduce the recirculation zone and reattaeh- ment length, and thus improve the flow fields downstream the step. With the increasing increments of the ab- solute CQ, the effect of suction control is more significant.

关 键 词：后台阶 吸气控制 数值模拟 流动分离 再附长度 

分 类 号：O359[理学—流体力学]