Plasma ignition and combustion

Electro-thermal-chemical (ETC) initiation and combustion offers the possibi lity to increase the performance of guns substantially as new propellant fo rmulations and high loading densities (HLD) can be safely ignited and burnt in an augmented way. This paper reports investigations of burning phenomen a in the low pressure region for JA2 and the effects of plasma interaction on ignition and study its influence on the burning rate. The comparison of transparent and opaque versions of the propellant is of special interest. E lectrically produced plasma can strongly influence the ignition and combust ion of solid propellants. Predominantly, plasma arcs influence strongly the burning of propellants by its radiation. The high intensity of the radiati on initiates burning with short time delays in the mus-range and high conve rsion during exposure also in the case of a stable burning. Radiation can p enetrate into the propellant interior and partially fragment at absorbing s tructures which could be artificially introduced or be inherently present a s in the case of a JA2 propellant. Simplified approaches based on the heat flow equation and radiation absorption can explain these effects at least o n a qualitative scale. Dynamic effects are understood by more sophisticated models.