Experimental study of high test peroxide micro-thrusters for small satellites

The results of an experimental study of a milli-Newton high test hydrogen peroxide microthruster are presented. The microthruster, which has been developed through the years by the Microsatellites and Space Microsystems Lab of the University of Bologna jointly with Sitael Forlì and FBK Trento, is now at its second design iteration. The target field of application for such microthrusters lies within small satellites with mass lower than 50 kg. Propulsion systems exploiting either heterogeneous or homogeneous hydrogen peroxide catalysis have been widely investigated in last decades as an alternative and "more green" solution compared to commonly used chemical monopropellant systems as Hydrazine based ones. Nevertheless, an in-depth analysis of the influence of operative conditions on the chemical decomposition of hydrogen peroxide for MEMS sized thrusters still lacks. This work tries to fill the gap, by proposing the design and implementation of the high test peroxide microthrusters test campaign that should allow to assess the efficiency of an heterogenous catalysis decomposition of hydrogen peroxide induced by a pillar patterned catalytic chamber. The results of the experimental study suggests that the design of the catalytic chamber along with the presence of integrated heating films allow to obtain an almost complete propellant decomposition, with mass flow rates in the range of 0.6 to 0.8 mg s−1 when 2 W of heat are supplied to the thruster. Nevertheless, some technical and technological issues still have to be addressed, as the deposition of evaporation residue within the catalytic chamber and the fluid backflow.