EXPERIMENTAL STUDIES OF THE PLASMA PROPELLANT INTERFACE FOR ELECTROTHERMAL CHEMICAL LAUNCHERS

A plasma-propellant interaction experiment ''PIPE'' has been construct ed to investigate the plasma-propellant interface physics, and plasma augmentation to the propellant burn rate. The experimental facility co nsists of an electrothermal plasma source that injects plasma to the s urface of solid or liquid propellants. The source (ET) is powered by a 340 mu F Maxwell capacitor (17 kJ at 10 kV, up to 100 kA, 400 mu s pu lse duration) via a pulse forming network (PFN). Experiments with JA2 granular solid propellant under vacuum operation (20 Torr base pressur e) showed incomplete burn of the propellant. However, the overall cham ber pressure is a factor of two higher than,that without propellant. P reliminary measurements showed that the burn rate with plasma injectio n has been increased by a factor of three at a pressure of 0.7 kbar co mpared to conventional ignition.