Numerical Study of Two-Stage-to-Obit Spacecraft Interstage Separation Mode

The design of the interstage separation mode of Two-Stage-to-Orbit (TSTO) spacecraft is very important. Numerical simulation can accurately predict the multi-body separation problem of fluid-structure coupling, such as stage separation. Coupled fluid control equations and rigid body motion equation, unstructured overset grid technology and dual-time method are used to solve the stage separation process of TSTO at Mach number 6 and altitude of 30 km. The motion characteristics and aerodynamic interference characteristics of the two stages are studied when the TSTO is separated at different angles of attack. The result shows that there will be strong aerodynamic interference between the two stages in the process of TSTO separation, which seriously affects the attitude control of the two stages and increases the risk. Compared with the separation at positive angle of attack, the separation of two stages at negative angle of attack has a larger distance and lower aerodynamic interference intensity, which is more favourable for the separation of the stages.