Design and analysis of emergency protection scheme for manned spacecraft under leakage condition

Spacecraft may encounter emergency pressure relief situations during manned space exploration missions, such as when micrometeoroids break through the bulkheads. The pressure emergency is one of the main threats to the missions in low earth orbit or deep space explorations to the Moon and Mars. It is critical to develop a pressure protection scheme for emergency contingencies. In this study, in order to improve the safety and reliability of spacecraft protection, a periodic recompression recovery scheme (PRRS) is proposed for cabin pressure protection. The PRRS adopts a combined mode of cabin emergency recompression, cabin pressure maintenance, gas recovery, and spacesuit protection, which can provide astronauts with a variety of safety protection methods. A mathematical model of cabin pressure control is established by using the lumped parameter method, and the gas consumption of three types of pressure protection systems are compared. The PRRS adopts the mature technologies and could provide the reliable pressure emergency protection. Compared with the traditional continuous gas supply scheme, the PRRS can reduce gas consumption by more than 85%. In the case of limited spacecraft gas resources, the PRRS promises a longer survival time for returning astronauts. This study can provide a design idea for the overall design of manned spacecraft in the future.