Combustion Behaviour of Advanced Solid Propellants.

Abstract

The study reports the effect of incorporation of Al and ammonium perchlorate (AP) individually and in combinatipn with each other on combustion pattern and specific impulse (Isp) of minimum signature propellants. Incorporation of Al obviates the combustion instability problems; however, it has marginal, effect on burning rates. The composition containing AP and zirconium silicate combination gives superior performance; however, its Isp is considerably lower than the composition incorporating 9 per cent AP. A combination of 6 per cent AP and 3 per cent Al gave 20 per cent enhancement in burning rate. and 12 s increase in Isp as compared to purely nitramine-based composition, cal-val results also reveal increase in energy output on incorporating AP and Al. Hot stage microscopic and propellant combustion studies indicate occurrence of intense decomposition reaction in case of AP-based compositions. To get useful information on these aspects and to provide supporting evidence for various prevailing theories3-8, nitramine-based double-base (DB) compositions with varying quantities of AP and AI were prepared and evaluated. A unique feature of this study was determination of ballistics including Isp by statically evaluating the grains in a small rocket motor while other researchers have reported strand and burner results and theoretical/sp for nitramine and AP based CMDB9. I.