Dual-jet coupling effects on flow field mechanism in shock wave/boundary layer interaction

In hypersonic flow, the coupling of shock wave/boundary layer interactions (SWBLI) induced by geometric discontinuity with shear layer will lead to a sudden increase in local heat flux. This paper focuses on the air rudder configuration and uses numerical simulation to investigate the regulation mechanisms of transverse jet, opposing jet, and their coupling effects on shock wave reconstruction, separation vortex evolution, and heat flux distribution. Numerical method was validated based on experimental data from the open literature and a grid-independent validation was completed. The results demonstrate that the bow shock induced by transverse jet can effectively suppress SWBLI on rudder lower surface, while the opposing jet reconstructing the leading-edge shock system to reduce local heat flux. However, single jet configurations induce detrimental local shock interactions, causing sharp heat flux peaks. In studies of dual-jet configurations, when the distance between the transverse jet and the rudder tip is three times the height of rudder, nearly 100 % coverage of the leading-edge region is achieved for protection, with heat flux reduced below 600 kW/m² in 50 % of the area. Compared to the average heat flux of 3567 kW/m² along the leading-edge symmetry line of baseline model, the dual-jet scheme demonstrates a reduction exceeding 2900 kW/m². This confirms the outstanding heat flux regulation effect of the synergistic action of dual-jet on the shock interaction flow field under appropriate configuration. Future research needs to establish a multi-parameter collaborative matching model to achieve synergistic optimization of the dual-jet scheme for both shock interference suppression and thermal environment control.