A two-dimensional Reynolds averaged Navier Stokes (RANS) simulation of a dual mode ramjet (DMRJ) combustor is performed, modeling the University of Michigan dual-mode combustor experimental setup operating in reacting mode with different equivalence ratios (φ). The simulations are carried out using a k-ω SST turbulence model and a steady diffusion flamelet model for non-premixed combustion. Air enters the isolator at Mach 2.2, stagnation pressure and temperature of 549.2 kPa and 1400 K respectively. Hydrogen is injected transverse to the flow direction and upstream of the cavity flame holder to simulate ramjet (φ = 0.29) and scramjet (φ = 0.19) modes of operation. Wall static pressure plots are used to validate numerical results against experimental data. Analysis of flow separation in ramjet mode due to the presence of a shock train in the isolator is carried out by means of numerical Schlieren images overlapped with contours of negative axial velocity, showing the effects of shock wave boundary layer interaction (SWBLI). Active control through wall normal boundary layer bleed in the separated flow region is implemented, which weakens the shock train and moves it downstream closer to the cavity. Bleed results in an improved stagnation pressure recovery in ramjet mode, with a marginal increase in combustion efficiency.

对双模式冲压喷气发动机（DMRJ）燃烧器进行了二维雷诺平均Navier Stokes（RANS）模拟，对密歇根大学双模式燃烧器实验装置进行了建模，该实验装置以不同的当量比（φ）的反应模式运行。对于非预混燃烧，使用k- ωSST湍流模型和稳定扩散小火焰模型进行了模拟。空气以2.2马赫的速度进入隔离器，停滞压力和温度分别为549.2 kPa和1400K。垂直于流动方向并在型腔火焰保持器的上游注入氢气，以模拟冲压喷气发动机（φ  = 0.29）和超燃冲压发动机（φ = 0.19）操作模式。墙体静压图用于根据实验数据验证数值结果。由于在隔离器中存在冲击波，在冲压喷射模式下进行的流分离分析是通过与负轴向速度轮廓重叠的数字Schlieren图像进行的，显示了冲击波边界层相互作用（SWBLI）的影响。通过在分离的流动区域中通过壁法向边界层渗漏实现主动控制，这会削弱冲击波并将其向下游移动，使其更靠近空腔。排气导致冲压喷射模式中的停滞压力恢复得到改善，燃烧效率略有提高。