带凹腔的支板火焰稳定器三维大涡模拟

为研究支板冷态流场,应用LES(大涡模拟)的方法对带凹腔的支板火焰稳定器在Ma=0.06和 Ma=0.09两种工况下分别进行三维数值模拟.对比试验和仿真结果表明:三维大涡模拟结果具有与试验相似的流场结构,定量对比试验和LES结果的尾涡脱落频率的最大相对误差为9.4%；支板尾部截面流向时均速度的最大相对误差为7.7%.表明数值模拟方法和边界条件设置的正确性和可信度.又对支板的三维流场进行分析:速度越大,支板尾涡的尺寸和强度越大；支板流场存在明显的三维效应,并且随着速度变大,三维效应越明显. 

Three-dimensional large eddy simulation of strut flame-holder with cavity

In order to study the cold flow field of strut,three-dimensional LES (large eddy simulation) of strut flame-holder with cavity at Ma =0.06 and Ma =0.09 was carried out respectively.The simulation results were compared with experiment data.It showed that the flow field structure of three-dimensional LES was similar with that of experiment.What's more,two quantitative comparisons in the frequency of wake vortex and time-averaged stream-wise velocity on strut rear section were made.And the maximum relative errors were 9.4％ and 7.7％ respectively,proving that the model of numerical calculation at boundary conditions was correct and believable.Then by analyzing the three-dimensional flow field of strut,a conclusion that the faster velocity means the bigger size and intensity of wake vortex.Besides,the result of three-dimensional LES shows an obvious phenomenon of three-dimensional effect which gets stronger when the velocity gets faster.