Combustion Studies on Paraffin Wax in Gaseous Oxygen and Nitrous Oxide

A series of static hybrid rocket firings were done in a laboratory scale motor using paraffin wax fuel with gaseous oxygen and nitrous oxide oxidizers. A five element swirl injector was used to inject the oxidizer at the head end of the motor. A pyrotechnic igniter was used to initiate the combustion. The combustion of fuel grain was carried out for a fixed duration and at different oxidizer injection pressures. The local regression rates, average regression rates and fuel mass consumption rates were found to increase with injection pressure; however it was observed that increase in oxygen injection pressure result in dense white smoky exhaust. The local regression rate, mass consumption rate and average regression rate were found of lower value for nitrous oxide oxidizer as compared to gaseous oxygen at same injection pressure.