Dynamic modeling and cycle performance analysis of a 3He sorption cooler

A 3 He sorption cooler is an attractive solution for sub-Kelvin applications due to its vibration-free operation, compact structure, and high reliability. However, existing studies mainly focus on experimental performance under specific operating conditions, while quantitative cycle-level performance prediction and optimization remain limited at the design stage. To address this gap, the present study develops a dynamic cycle-performance model that quantitatively simulates the evolution of the system temperature, pressure, and 3 He distribution throughout a complete operating cycle, and predicts cycle-level performance metrics including the effective operating time ratio, the equivalent input power, and the average cooling efficiency. Based on the model, the effects of main sorption-pump parameters, including the activated-carbon mass, activated-carbon bulk density, desorption temperature, and total 3 He charge amount, are systematically analyzed. Parametric studies identify the optimal activated-carbon mass, bulk density, desorption temperature, and total 3 He charge amount for a cooling load of 1.061 μ W at 0.3 K, corresponding to peak effective operating time ratios of 99.6%–99.9%, minimum equivalent input powers of 1.16–1.63 W, and maximum average cooling efficiencies of 6.50 × 1 0 − 7 – 9.12 × 1 0 − 7 . The proposed model provides a useful tool for cycle performance prediction and trade-off analysis, and offers guidance for the development of compact and high-reliability cryogenic platforms for low-temperature applications.