Abstract: One of the high-enthalpy intermittent wind tunnels is the free-pistonshock tunnel, where a free heavy piston compressor is used. It is first suggested and built by Prof. R. J.Stalker at the Australian National University, Canberra, Australia. The free-piston shock tunnel is unique in its ability to provide very-high-temperature, high-pressure test conditions, and can be used to produce test section flows with stagnation enthalpies greater than those corresponding to earth satellite velocity, so this type of...