Studies on the ballistic range/shock tunnel driven by circular variable section shock tube

The continuous development of the aerospace industry has prompted the space vehicle to pursue higher and higher flight performance. Accordingly, higher requirements have been put forward for flight simulation ground experiment equipment such as ballistic ranges/shock tunnels. A circular variable-section shock tube driving ballistic range/shock tunnel was proposed in this paper to improve the flight simulation capability of the ballistic range/shock tunnel. The wall profile of the circular variable-section shock tube was designed using the nonlinear characteristic line theory of the axisymmetric coordinate system in shock wave dynamics. The flow fields of the circular variable-section shock tube and the ballistic range/shock tunnel driven by the circular variable-section shock tube were analyzed through numerical simulation, and the performance of the circular variable-section shock tube driving ballistic range/shock tunnel was evaluated. The results obtained showed that: the designed circular variable-section shock tube wall profile can ensure the quality of the flow field during the shock wave motion process; using a variable-section shock tube with a diameter ratio of 35 cm:10 cm and a low-pressure area pressure of 1000 kPa to generate 3Ma incident plane shock waves to drive a ballistic target can theoretically accelerate a mass of 0.678 kg to a flight speed of 2040 m s−1 in a vacuum tube of 3 m (corresponding to 6Ma flight in 300 K atmosphere); using the driving mode of a converging section of the variable-section shock tube followed by an expanding nozzle to drive the shock tunnel can reproduce the aerothermodynamic environment of the real atmosphere when an aircraft flies at 6Ma. In general, it is feasible and advantageous to use a circular variable-section shock tube to drive ballistic targets/shock tunnels.