Dynamics of a Small-Scale Hydrogen Peroxide Vapor Propulsion System

Abstract

A novel thruster concept for CubeSats and other small satellites using hydrogen peroxide vapor as a propellant is presented and evaluated. This concept leads to the highest theoretical vacuum specific impulse of any hydrogen peroxide system (greater than 200 s) while retaining the advantages of small size and simple construction typical of liquid monopropellant systems. For a nominally sized thruster, the theoretical thrust can be varied from 0.5 to 8 mN simply by changing the temperature of the tank in which the liquid hydrogen peroxide is stored. Theoretical performance parameters of liquid and vapor thrusters are compared. A prototype system (tank, heater, platinum catalyst, and nozzle) is constructed and tested. It is found that, when vapor is allowed to flow over the catalyst, its temperature increases slowly at first and then increases rapidly when the vapor hydrogen peroxide () mole fraction exceeds approximately 0.5 and a catalyst temperature of about 400 K is reached. An analysis of the equilibrium state on the catalyst indicates that this temperature corresponds to the condition in which the surface coverage shifts from predominantly water to a significant fraction of open platinum sites where can adsorb and react.