The mechanical expansion reentry vehicle has become the focus of deep space exploration because of its good deceleration effect and high stability. However, due to its special aerodynamic shape, its surface heat flux characteristics are different from traditional reentry vehicles. In this paper, the Two-Temperature model is introduced to simulate heat flux distribution. The influence of different structure parameters and flight parameters on the flow field structure and surface heat flux is also analyzed. The research shows that the Two-Temperature model can improve the prediction accuracy and that the heat flux may peak at the both the head and shoulder of the vehicle. Structural parameters RB, RN, and θ have an obvious negative effect on QO. RB, RN, RR, and LZ have a negative correlation with QR. QR drops first and then rises as θ increases and RS decreases. Flight parameters Ma have a positive effect on QO and QR while H is negative; α makes the heat flux distribution asymmetric.
As humans continue to explore the aerospace field, higher demands have been placed on new types of propulsion systems. Meanwhile, active secondary flow has been applied to various aspects of engines over the past seventy years, significantly enhancing engine performance. For the new generation of propulsion systems, active secondary flow remains a highly promising technology. This article provides an overview of the application of active secondary flow in engines, including a review of the past research on the secondary jet flow field, and an introduction of the more prominent applications of the jet in engines and its research progress. Finally, the problems existing in the current application of the secondary jet are summarized, and the future direction of the research is anticipated.