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应用三维大涡模拟(LES)方法对C1x模拟试验器进行了数值模拟,以研究转角涡脱落引起的声涡耦合现象.结果表明:与二维和轴对称LES相比,三维LES方法可以准确捕获转角涡脱落运动的三维特性及锁频现象.根据转角涡脱落是否在腔内形成声反馈循环过程可将其分为两类问题,第1类形成声反馈循环涡;第2类形成自耗散涡.燃烧室的台阶扩张比、台阶前后长径比是影响两类转角涡脱落现象的重要结构参数.
The numerical simulations of the C1x simulator were carried out by using the three-dimensional large eddy simulation (LES) method to study the acoustic vorticity coupling caused by the angular vortex shedding.The results show that the three-dimensional LES method can accurately capture The three-dimensional characteristics and frequency-locking phenomenon of angular vortex shedding can be divided into two types according to whether the vortex shedding forms acoustic feedback loop in the cavity, the first type forms the acoustic feedback circulating vortex and the second type forms self-dissipative Vortex. The step expansion ratio of the combustion chamber and the aspect ratio before and after the step are important structural parameters that affect the phenomenon of two kinds of corner vortex shedding.