Electric Pump Cooling System Design For High Performance Moon Engine

HERACLES (Human-Enhanced Robotic Architecture and Capability for Lunar Exploration and Science) is a robotic transport system designed for the transportation of resources to and from the Moon, funded by the European Space Agency (ESA), the Japanese space agency (JAXA), and the Canadian Space Agency (CSA). The program includes a lander called the European Large Logistic Lander (EL3), a lunar ascent element, and a rover. The lunar lander can be implemented in various configurations depending on the needs, with a payload of approximately 1.5 tons. The system has been designed to support the Artemis program and to conduct lunar exploration using the Lunar Gateway as a starting point. The main objectives of the EL3 mission involve the transportation of resources useful for future human exploration, demonstrating and certifying new technologies and procedures useful for future Mars exploration, and enabling the transportation of lunar samples back to Earth. The objective is to be achieved through the use of an electric pump-fed engine that ensures the supply of energy to the propellants compared to the low pressure present in the tanks. The use of electric pumps for access to space has been used since 2017 when the Electron, a liquid-propellant rocket from the American-New Zealand company Rocket Lab, was first launched; however, they have never been used for space applications. As demonstrated by the Electron, the use of electric pumps for pumping propellants from the tanks to the combustion chamber allows for increased pumping cycle efficiency with a simpler and more compact design, but with a higher weight due to the presence of batteries needed to power the electric motors. The EL3 mission also involves the use of a pair of electric motors for pump operation. Despite the high efficiency of the motors and developed inverters, the system requires a dedicated apparatus for the disposal of excess heat, which if not properly dissipated would accumulate on the mechanical parts, affecting their performance. The purpose of this thesis is to determine the best method for removing and disposing of heat generated by the electric apparatus and thus maintaining the temperatures of the two systems within the established limit, all while meeting the required specifications. To begin the study, existing thermal control systems in literature were analyzed. Subsequently, each solution was applied to the case at hand to identify the best option capable of meeting the mission requirements. Since it is required to operate in space, the removed heat must be rejected externally or accumulated internally without compromising the functionality of the components by subjecting them to high temperatures; the study also involves the identification of one or more elements that can absorb heat without causing significant problems for the system.