EXPERIMENTAL CHARACTERIZATION OF A HYDROGEN PEROXIDE-BASED THRUSTER FOR SMALL SATELLITES

The growing interest of the space market in the use of small satellites (e.g. CubeSats) requires the research of proper miniaturized propulsive systems for attitude, trajectory and orbit control. Chemical propulsion can be suitable for this kind of application, when the required ΔV is too low for electric propulsion systems. In particular, monopropellant and hybrid rockets can provide good Isp performance, re-ignition and throttling capability with relative system simplicity, due to the single flow feed line. Being the research oriented towards green solutions, chemical thrusters based on hydrogen peroxide are studied as candidates for these applications. Their performance is strictly related to the catalytic chamber: the catalyst’s task is to decrease the activation energy leading to the decomposition reaction acceleration. The heat released by decomposition can be then converted directly into propulsive energy for monopropellants, which can provide the necessary power for mixture ignition in the case of hybrids. In this scenario, the University of Naples “Federico II” (UNINA) is involved in several projects in which hydrogen peroxide finds its application as a monopropellant or oxidizer in the case of the hybrid system, in combination with polymeric fuel grains. A laboratory is available at the Grazzanise (CE) military base where, in collaboration with the Air Force Academy, a test bench has been set up to carry out tests on various rocket engines. Small thrusters (1N class) have been designed to provide nanosatellites with formation flying and orbital manoeuvre capability, and ground breadboards were tested. A load cell was used to measure the thrust, while pressure transducers and thermocouples have been positioned at different points in the chamber and upstream of the nozzle. Results are discussed to study the effects of several parameters including chamber pressure and catalyst material on decomposition efficiency and thruster performance for the monopropellant configuration. Further activities are ongoing for the complete characterization of this kind of architecture in both propulsive modes, to optimize the design for a flight application.