Development of the Atmosphere Management System of the EDEN Next Gen greenhouse module for long-term space missions

Abstract

Main goal of this thesis was to develop a first design of the atmosphere management system (AMS). This includes the sizing of the different components and the proof of feasibility concerning the required dimensions of the components compared to the available space in the module. Therefor, requirements regarding the supportive external infrastructure, the overall greenhouse module, and the AMS were identified. In addition, assumptions for the implementation of the AMS were defined. After a detailed systems analysis including the single components, their interrelations, the required interfaces, the occurring internal and external loads, and the definition of system boundaries, a system strategy was developed. Although the AMS of the MTF was completely redesigned for the operation in space conditions some adoptions could be made. Also during the design proceeding, particularly at the dimensioning process of the single components, some practices adopted from the MTF could be applied. The final outcome is a modular concept with the following components. Air circulation generated by fans guarantees a continuous air movement within the cultivation area and counteracts air pockets with the help of a duct system. This loop of cycling air forces the warm, humid, and VOC (volatile organic compound) enriched atmosphere of the cultivation area through the duct system equipped with a sequence of air treating units. After mechanically removing particles with a pre- and HEPA-filter, a condensing heat exchanger (CHX) dehumidifies the air and a heater unit tempers the cold air again. Afterwards trace contaminants are chemically eliminated by a VOC-filter. Finally, the air composition control regulates the oxygen and carbon dioxide concentration.