• CN：11-2187/TH
• ISSN：0577-6686

›› 2012, Vol. 48 ›› Issue (14): 97-103.

• 论文 •

### 基于准 /LES模型的汽车外流场数值模拟

1. 武汉理工大学汽车工程学院;湖南大学汽车车身先进设计制造国家重点实验室
• 发布日期:2012-07-20

### Aerodynamic Simulations of Vehicle by Using the Hybrid Semi /LES Model

WANG Yiping;GU Zhengqi; DENG Yadong;SU Chuqi

1. School of Automotive Engineering, Wuhan University of Technology Key State Laboratory of Advanced Technology and Manufacture for Vehicle Body, Hunan University
• Published:2012-07-20

Abstract: The hybrid RANS/LES approach is employed to compute the exterior time-average flow field of a vehicle. The three-equation turbulence model is employed as the RANS part in current research. To overcome the numerical oscillation induced by the normal stress ( ) transport equation and the elliptic equation which is used to constructed relaxation function f22 in the model, the algebraic form of the normal stress ( ) equation and the new eddy-viscosity equation are derived, based on the Boussinesq approximation and non-dimensional analysis. Then, the new hybrid semi- /LES model which can be used to compute the vehicle exterior flow field is obtained. The control equations of the new model employed the same k and equations as those in the realizable /LES model in commercial software Fluent, with an algebraic equation for and new eddy-viscosity programmed by Fluent-UDF. The comparisons between the results obtained by semi- /LES model and other hybrid RANS/LES models, entire LES and wind tunnel experiment show that the new model is more accurate and efficient to simulate the flow separation around the body surface and the wake vortex.