A COMPACT SHOCK-ASSISTED FREE-PISTON DRIVER FOR IMPULSE FACILITIES

A free-piston driver that employs entropy-raising shock processes with diaphragm rupture has been constructed, which promises significant th eoretical advantages over isentropic compression. Results from a range of conditions with helium and argon driver gases are reported. Signif icant performance gains were achieved in some test cases. Heat losses are shown to have a strong effect on driver processes. Measurements co mpare well with predictions from a quasi-one-dimensional numerical cod e.