Preliminary Design and Sizing of an Orbiter Propulsion S/S for a Mars Mission Using EcosimPro

This Master's thesis contributes to the Deep Space Platform (DSP) Phase A study, conducted in collaboration with Thales Alenia Space Italy (TASI) for the Technical Offer commissioned by the Italian Space Agency: "Phase A Industrial Activities of the Deep Space Platform Programme for Multi-Mission Activities Beyond Low Earth Orbit". The company's objective is to deliver a low-cost, high-flexibility, multi-mission platform tailored for the New Space Economy and designed to support future missions to the Moon, Mars, and Near-Earth Asteroids (NEAs). The primary focus of this work is the development of the platform's Chemical Propulsion Subsystem (S/S) numerical model, utilising the EcosimPro simulation environment and its leverage of the specialized European Space Propulsion System Simulation (ESPSS) libraries. These libraries result from the European Space Agency's endeavour to establish an official European platform dedicated to analysing and simulating the behaviour and performance of complex spacecraft and launch-vehicle propulsion technologies, with the strategic aim of reducing the future necessity and cost of performing extensive physical testing on propulsion systems. The modelling process followed a phased, bottom-up approach: first, defining the Pressure Control Assembly to manage the gaseous section and verify correct tank pressurisation; second, modelling the Liquid Feed System to simulate the operation of the Reaction Control Thrusters and the Main Engine; and finally, integrating these into the complete EcosimPro system schematic, encompassing the entire fluid network from pressurant gas tanks to the thrusters and main engine. This comprehensive model served as the base for preliminary analyses, demonstrating a correct transient behaviour of system variables. Crucially, the validation of key component dimensions, such as pipes and tanks, performed within the model, produced performance characteristics comparable to the experimental data provided by component manufacturers. The resulting numerical framework supports the detailed design and formal closure of system requirements for the DSP Propulsion S/S, thereby establishing the technical foundation for the Reduced Development Model (DM). This DM will be essential for correlating and anchoring the EcosimPro model against empirical test data during the forthcoming Preliminary and Critical Design Review (PDR-CDR) phases.