Design, Analysis, and Verification of a Sealed Container for Lunar Regolith Simulant Containing Water Ice

This paper presents a design method for a sealed container intended to hold lunar regolith simulant containing water ice, developed for ground-equivalent drilling tests of the Chang’E-7 mission. Taking into account the characteristics of vacuum and low-temperature testing environments, the container features a composite inner-outer lid structure and a knife-edge soft metal sealing mechanism to ensure effective sample containment. To study the influencing factors of the knife-edge soft metal seal, a theoretical model of the gas leak rate in the transitional flow regime was established, which identified the primary determinants of sealing performance. Finite element simulations were employed to optimize the geometry of the knife-edge. Subsequently, a series of performance verification tests were conducted in a thermal-vacuum environment with a pressure level of 10 −2 Pa and a temperature of −75 °C. The results indicated that the leakage rate of the container remained below 2.34×10 −9 Pa·m 3 /s, the air intake error was within ±5%, and the water content loss rate was less than 30%. These findings demonstrate that the container provides high-fidelity sealing of the lunar regolith simulant containing water ice, thereby fulfilling the requirements of the Chang’E-7 drilling tests for reliable sample containment.