Numerical study on the flow characteristics of a start supersonic inlet using direct numerical simulation

This study investigates the internal flow field characteristics of a start inlet using the direct numerical simulation method. The results indicate that a transition of the laminar boundary layer is observed under the influence of the reattachment shock wave. The first incident shock wave/boundary layer interaction (SWBLI) shows similar characteristics with traditional SWBLI studies. However, due to the different state of the incoming boundary layer, the second λ SWBLI shows that this SWBLI does not have a significant effect on the low-frequency component. The expansion corner has a stronger effect on turbulent features than the λ shock, but the opposite is true for the average features. Therefore, special care should be taken when directly applying the conclusions of the SWBLI to the complex flow field of inlets. In addition, the turbulent injection and sweeping events at the ld/δ0=0.3 plane in the isolator exhibit an opposite behavior to that observed in the incoming boundary layer. The significance of this study is to reveal the features of turbulence in a start supersonic inlet.