A pulse forming network and test fixture for screening electrothermal chemical candidate propellants

A pulse power supply has been designed to support the development and evaluation of candidate propellants for an electrothermal chemical gun program at the Army Research, Development and Engineering Center. The flexibility needed for this evaluation is achieved through the modular design of the test fixture and power supply. The test fixture is composed of a plasma chamber and an instrumented combustion chamber interconnected by a convergent-divergent nozzle. The combustion chamber is terminated by an exhaust nozzle and overall thrust is measured. The volume of both chambers and nozzle configurations can be varied to optimize performance. A 10 mm gun tube is an option. The power supply is readily reconfigured to provide either an RLC or PFN (pulse forming network) discharge. Either configuration can store up to 34 kJ and provide a pulse between 0.5 and 2 ms. Load behavior and the effects of parasitic energy losses on circuit performance are presented. The results are compared with PSpice circuit models