Dynamic characteristics analysis of gas leakage and safety strategies in space stations

Gas leakage in space stations poses a severe threat to astronaut safety and mission reliability. The study proposes a dynamic gas leakage model based on one-dimensional isentropic flow theory and choked flow leakage characteristics, analyzing quantitative relationships among equivalent leakage area, module volume, and leakage duration. A leakage time prediction equation is derived and validated through case studies that calculate leakage time thresholds for experimental, node, and service modules under non-replenishment conditions. Furthermore, by considering pressure recovery dynamics, the gas replenishment time for different modules under varying equivalent leakage areas is determined, with the critical maximum tolerable leakage area quantified as 7 mm². This enables the calculation of reference times for evacuation protocols when this threshold is exceeded. The proposed dynamic leakage model, leakage time prediction equation, and gas replenishment time prediction provide theoretical support for optimizing on-orbit emergency response and maintenance strategies, offering critical operational references for safeguarding astronauts’ lives while demonstrating significant engineering value for space station operational safety.