Vapor Compression Refrigeration System for Space Exploration

Food preservation is going to be a key need for long term human space flight and vapor compression cooling technology is considered to be a leading enabler to preserve food. This research underlines the key benefits of vapor compression refrigeration systems for space applications considering the energy efficiency, weight of the system, overall space management, scalability and most importantly reliability of the system. Major concerns with vapor compression systems are related to liquid floodback on the compressor and based on the learning from parabolic flight tests and an inclinable test stand, this said system tries to address liquid floodback related challenges by employing design modifications especially in the region of variable speed compressor working logic with help of suction line heat exchanger. The paper will also provide a future roadmap to optimize system weight, temperature of application, energy efficiency, reliability of the system, and scalability using a “Yardstick” approach which can provide different specifications for storage capacity. The research conducted did not consider other refrigeration system technologies. Additionally, a prototype vapor compression compartment that would fit several International Space Station (ISS) drawer sizes is presented.