The Design Of The Aerodynamics And Structure Of A Large Pulse Tunnel

A hypersonic pulse tunnel is designed in this paper, which has multiple running modes based on gun tunnel and shock tube theory. Its design Mach number is 4, 5, 6, 7, 8 and 9, The max driving pressure is 20.0MPa, simulated altitude is 15, 20 and 25Km (matching Ma=4, 6 and 8 respectively). The nozzle of the tunnel has two calibers: 2.0m (for Ma=4.0, 5.0 and 6.0) and 2.5m (for Ma=7.0, 8.0 and 9.0).The max diameter and length of the test models is 1m and 4~5m. The whole length of the tunnel is 110m, with 22m driver section and 38m driven section. The inner diameter of the driver section and the driven section is 0.6m. There are three drive modes in this tunnel: air to air (gun tunnel), hydrogen and nitrogen to air (shock tunnel, Ma=6.0), helium and air to air (shock tunnel, Ma=8.0). Aerodynamic parameters measurement and flow visualization can be realized in this tunnel.The aerodynamic parameters, systematic design and structure analysis of tunnel are researched in this paper. The balanceable piston theory and perfect gas model are used as building block to design tunnel, and the resulting tunnel can generate uniform flow, which can provide long experimental time with high Mach number, given enthalpy and Reynolds number, thus, the scramjet and ramjet aircraft can be studied in this tunnel. Compared with the counterpart of foreign facilities, the basic structure and size are confirmed. According to the structure of this tunnel, the strength is checked and the security of structure is validated.