Experimental Investigation of Liquid Phase Breakup in Solid Fuel Rockets

Abstract

Solid rocket motors (SRM)s commonly use aluminized composite propellants. The combustion of aluminum composite propellants in SRM chambers lead to high temperature and pressure conditions resulting in the liquid alumina as a combustion product. The presence of liquid alumina in the flow presents problems such as; chemical erosion of propellant, and mechanical erosion of nozzle. One method of solving the problem of liquid alumina in flow is to change the SRM geometry to induce liquid breakup and suspend the alumina in the flow thus avoiding erosive behavior. To validate numerical simulation methods for geometric breakup induction simulation models of alumina flow can be compared to air and liquid water flows, and the air-liquid water flow models then compared to water-air experimental results. This study investigates experimental geometric induced liquid breakup behavior for the implementation of the alumina flow and nozzle geometry simulation in SRM design. A rectangular chamber was considered for experimental and simulation to explore the air-water flow behavior. The suspension of water was induced with a triangular shaped jump. The resulting two phase flow was examined using photography technique. Significant incitement in the air-water behavior was observed due to geometry modification. Replication of experimental results was simulated with some accuracy.