Transient and POD analyses of supersonic intake for combined-cycle engine

This study investigated the flow characteristics of the high-flow path of a two-dimensional supersonic intake in a turbine-based combined-cycle engine utilizing Reynolds-averaged Navier–Stokes (RANS) and detached eddy simulation (DES) turbulence schemes with a moving mesh in ANSYS to analyze the flow effects of varying rotational cowl angles. In addition, proper orthogonal decomposition (POD) was employed to analyze the flow modes. This study revealed that the mass flow rate and pressure recovery increased linearly with an increasing cowl opening angle, and fluctuations were observed when the cowl was positioned parallel to the ramp surface in DES transient solutions. Conversely, a significant decrease in mass flow rate and pressure recovery ratio occurred when the cowl angle was located at fixed − 4.78° in steady solutions. POD utilizing snapshots derived from RANS k-wSST and DES indicated that the first to fourth modes were dominant, accurately representing the original velocity field with a cumulative mode energy ratio of over 80 %.