用基于M-SST模型的DES数值模拟喷流流场

COMPUTATION OF LATERAL TURBULENT JETS USING M-SST DES MODEL

脱体涡数值模拟方法(dettached eddy simulation,DES)是把雷诺平均Navier-Stokes方程(RANS)方法及大涡模拟方法(LES)结合起来模拟有脱体涡的湍流流场的数值模拟方法,其主要思想是在物面附近解雷诺平均Navier-Stokes方程、在其他区域采用Smagorinski大涡模拟方法。本文在剪切应力传输(SST)湍流模型的基础上用DES及混合非结构网格数值模拟具有横向喷流的湍流流场,算法采用Osher逆风格式,利用该套程序(包括网格生成及算法),对导弹在不同马赫数下的喷流流场进行了数值模拟,并与同时开展的实验研究的结果进行了对比,结果表明用该方法处理这类问题是较准确的。

DES(detached eddy simulation) is a hybrid method combining RANS and LES to simulate fiowfields with detached eddies. The main idea is that, RANS is used near the wall and LES method is used in the other region of the field. In this paper, DES method based on M-SST was used to simulate the complicate turbulence flows on hybrid unstructured grids and the Osher scheme was used for the spatial discretisation. The computations of the flow around a missile with a lateral jet was performed by using the newly-developed codes. The obtained results demonstrate that DES method is efficient for some simulation of the separated turbulence fiowfields.