Hybrid Propulsion System: Novel Propellant Design for Mars Ascent Vehicles

This chapter briefly introduces hybrid rocket propulsion for general audience. Advantageous of hybrid rockets over solids and liquids are presented. This chapter also explains how to design a test setup for hybrid motor firings. Hybrid propulsion provides sustainable, safe and low cost systems for space missions. Therefore, this chapter proposes hybrid propulsion system for Mars Ascent Vehicles. Paraffin wax is the fuel of the rocket. Propulsion system uses CO2/N2O mixture as the oxidizer. The goal is to understand the ignition capability of the CO2 as an in-situ oxidizer on Mars. CO2 is known as major combustion product in the nature. However, it can only burn with metallic powders. Thus, metallic additives are added in the fuel grain. Results show that CO2 increase slows down the chemical kinetics thus reduces the adiabatic flame temperature. Maximum flammability limit is achieved at 75% CO2 by mass in the oxidizer mixture. Flame temperature is 1700 K at 75% CO2. Ignition quenches below the 1700 K.