Numerical Study of Liquid Phase Hydrogen Peroxide Decomposition in Catalytic Micro-reactors

Hydrogen peroxide has recently been considered as a monopropellant in micropropulsion systems for the next generation of miniaturized satellites (‘nanosats’) due to its high energy density, modest specific impulse and “green” characteristics. Efforts at the University of Vermont have focused on the development of a MEMS-based microthruster that uses the catalyzed decomposition of hydrogen peroxide to generate thrust and impulse-bits commensurate with the intended micropropulsion application. The present study is a computational effort to investigate the initial decomposition of the monopropellant as it enters a catalytic chamber. Two-dimensional numerical models of the monopropellant in microchannel geometry have been developed and used to characterize the performance of the monopropellant before vaporization occurs. The results of these studies show that in the absence of a non-diffusive mixing mechanism at the microscale, decomposition of the monopropellant occurs very slowly. A method for enhancing decomposition via the introduction of gas bubbles into the flow is studied, and found to increase decomposition for a given length by over 57%.