Hybrid Rocket Motor (HRM) Test Stand: An Investigation of the Effects of Additives

Abstract

In comparison to solid and liquid fueled rockets, hybrids are attractive for their relatively low cost, simple design, and safety, while combining some of the characteristics of both liquid and solid fueled rockets. This paper describes a hybrid rocket motor (HRM) design that was constructed for testing fuels with little to no known experimental data. The HRM utilizes nitrous oxide as the propellant oxidizer and was chemically combusted with paraffin wax based fuels. Paraffin wax is a relatively new type of hybrid rocket fuel and has ample opportunity for research. The paraffin wax was tested alone as a baseline comparison test as well as mixed with two additives: lithium aluminum hydride and magnesium powder. These additives act as performance enhancers in the fuel grain with each additive mixed at 5% and 10% of the fuel mass. This project allowed for 25 total test fires with different propellant combinations. The data was compiled, analyzed, and has given insight to the magnitude in which the new type of fuel and/or the use of additives affect the efficiency of the hybrid rocket engine.