Effect of non-uniform incoming flow on the mixing enhancement in a scramjet cavity combustor

Abstract

Mixing in the combustion chamber is influenced by the velocity distribution of the inlet airflow. Numerical simulations are carried out by using the 3D coupled implicit Reynolds-averaged Navier-Stokes (RANS) equations and the SST k-ω turbulence model. This article compares the flow field characteristics of non-uniform flows with uniform flows. The results show that the penetration depth increases by 22% in the case of a decreasing velocity distribution along the longitudinal direction compared to the increasing velocity condition. The difference in total pressure loss compared to uniform flow is greater than 4%. The mixing coefficient in the cavity is only 81% of uniform flow. The two-hole jet flow approach is able to rapidly reach 90%. The study shows that the non-uniform inlet has a considerable impact on fuel mixing. The high velocity region near the jet hole contributes to the mixing performance of the engine combustion chamber.