摘要
采用基于M enter k-ωSST两方程湍流模型的脱体涡模拟(D etached Eddy S im u lation,DES)方法,求解N av ier-Stokes方程,数值模拟了超音速下圆柱底部的大分离流动。脱体涡模拟在近物面区采用雷诺平均方法,在其它区域采用Sm agorinsk i大涡模拟方法,兼具前者计算量小的优点和后者能模拟大分离湍流流动的优势。与雷诺平均方法的计算结果进行对比发现,DES方法可以更好地模拟分离涡的发展,得到的底部径向压力分布的时间平均值与实验值吻合。
Aim. Having failed to find in the open literature detailed technical information in applying DES （Detached Eddy Simulation） to simulating massively detached flow of cylinder-base, we have to work out such information ourselves. In the full paper, we give brief introduction to DES method and to Menter＇s κ-ω SST two-equation turbulence model but we put our emphasis on technical details, some of which are particularly worth being discussed. We now discuss three of these details with the aid of calculated results shown in Figs. 2-6 in the full paper： （1） Fig. 2 gives two curves; the top curve is for RANS （ReynoldsAveraged Navier-Stokes） method and the bottom curve is for DES method; the curves show clearly that unsteady feature of flow can be discovered by DES but not by RANS; （2） Figs. 4 and 6 show instantaneous pressure contours at cylinder-base computed by DES and they show clearly that the flow is nonaxisymmetric; （3） with the results already calculated , we can magnify a small part of Fig. 4; such magnification can show that under shock disturbance, the separated large eddy breaks into many irregular small scale eddies.
出处
《西北工业大学学报》
EI
CAS
CSCD
北大核心
2006年第5期544-547,共4页
Journal of Northwestern Polytechnical University
关键词
脱体涡模拟
大涡模拟
大分离流动
Detached Eddy Simulation （DES）, unsteady feature, massively detached flow
