Development of a thermodynamic model for a cold cycle 3He-4He dilution refrigerator

A thermodynamic model of a He-3-He-4 cold cycle dilution refrigerator with no actively-driven mechanical components is developed and investigated. The refrigerator employs a reversible superfluid magnetic pump, passive check valves, a phase separation chamber, and a series of recuperative heat exchangers to continuously circulate He-3-He-4 and maintain a He-3 concentration gradient across the mixing chamber. The model predicts cooling power and mixing chamber temperature for a range of design and operating parameters, allowing an evaluation of feasibility for potential He-3-He-4 cold cycle dilution refrigerator prototype designs. Model simulations for a prototype refrigerator design are presented. (C) 2016 Elsevier Ltd. All rights reserved.