Conceptual Design of a Synergistic Propulsion System for the International Space Station (ISS)

In this study, three different concepts of synergistic propulsion systems for the orbit control system of the International Space Station (ISS) are proposed. Their application was examined by means of numerical simulation. As propellants, selected waste fluids from the Environmental Control and Life Support System (ECLSS) are used. Possible future evolutions towards a highly regenerative life support system are taken into account. Resistojets and/or arcjets were chosen as thrusters. A detailed concept of an arcjet fueled by waste fluids was developed. It is based on the development of direct-current-arc-plasma generators suitable for the utilization of oxygen- containing gases like water steam, oxygen and carbon dioxide. The operation of the propulsion concepts onboard ISS was examined numerically with the software tool IRIS++, which allows the attitude and orbit dynamics of spacecrafts to be simulated. Results demonstrate that the drift phase during a reboost cycle can be increased significantly. A comparison of the system mass between the synergistic propulsion systems and the conventional system shows a high potential of reducing mass supplies to ISS.