Design and Experimental Validation of a Power-Free Diffusion Absorption Refrigerator for Lunar Rovers

Abstract

Diffusion absorption refrigerator (DAR) systems operate solely by heat input and gravity and do not require mechanical compressors or electrical power. They are suitable for environments with limited or unstable power supplies, such as future lunar missions, where strict resource constraints demand reliable and low-power thermal management. In this study, a numerical model was developed to predict DAR performance under reduced-gravity conditions. The model incorporates thermodynamic conservation laws, fluid dynamics, heat and mass transfer, and gravitational effects. It identifies how the structural configuration of each component influences overall system performance. Based on the numerical results, an experimental apparatus was constructed. Experiments were conducted under atmospheric pressure to validate the model assumptions. The system achieved a cooling temperature of −16 ℃ at a heat input of 60 W. This result confirms that the apparatus provides meaningful cooling capacity. The comparison between experimental data and numerical predictions evaluates the validity of the model and identifies the sources of discrepancies.