Yue WANG, Yun Peng WANG
DOI Number: XXX-YYY-ZZZ
Conference number: HiSST 2024-00132
Parallel-staged two-stage-to-orbiter (TSTO) vehicle is one of the promising next-generation reusable launch vehicles and comprises the booster and the orbiter. However, the TSTO hypersonic stage separation introduces strong shock waves and results in complex aerodynamic interaction into the interstage flowfield, which increases the risk of the stage separation and would determine the success of the launch mission. Thus, the longitudinal stage separation (LSS) is proposed, in which the orbiter accelerates along the upper surface of the booster with the unnoticeable interstage gap, so the strong shock-shock interaction (SSI) might be absent in the interstage flowfield. The dynamic tests of the TSTO stage separation are conducted in the JF-12 hypersonic flight condition duplicated shock tunnel at Mach 7. The TSTO vehicle comprises the wave-rider and the spaceplane as the booster and the orbiter. The dynamic test methodology of the multi-body vehicle stage separation in the short effective test time ground facility is clarified, including the high-speed pneumatic ejection to launch vehicle model system (HPELS) to make the LSS and high-speed Schlieren visualization and image processing techniques to capture the separation trajectory. Besides, the unsteady shock wave structure and wall pressure are also observed and examined. The LSS of the TSTO vehicle in the JF-12 shock tunnel is examined at angles of attack (AoA) of 8.3 and 4.5 deg. The results show that the small interstage gap of LSS leads to weak type I and VI SSI, with short-duration weak shock reflections at a high AoA. Furthermore, no shock reflection is observed at a small AoA. Additionally, no stage re-contact is observed, and the safety and feasibility of the LSS principle for the parallel-staged TSTO vehicle are demonstrated.