Effects of Thermal Conductance in the Cooling Stage of a 4K-GM Refrigerator on Refrigeration Capacity
This paper describes the effects of thermal conductance in the cooling stage of a 4K-GM refrigerator on its refrigeration capacity. Calculation of the temperature difference between the gas and cooling stage in the expansion space of a 4K-GM refrigerator has shown that the thermal conductance between the gas and cooling stage is inadequate, and the heat transfer loss is too large to be ignored. Hence, we have made improvements in the shape and material of the cooling stage to increase thermal conductance, and have been successful in increasing refrigeration capacity at 4.2 K from 2.2 W to 3.0 W.
KeywordsHeat Transfer Thermal Conductance Cooling Stage Heat Transfer Area Expansion Space
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