A pulse tube cryocooler with a cold reservoir

• Published in: Cryogenics (Guildford) 2013-02, Vol.54, p.30-36
• Main Authors: Zhang, X.B., Zhang, K.H., Qiu, L.M., Gan, Z.H., Shen, X., Xiang, S.J.
• Format: Article
• Language: English
• Subjects: Cold pressing; Cold reservoir; Cooling; Cooling capacity; Displacement; Mass flow; Phase shifting; Pistons; Pressure waves; Pulse tube; Pulse tubes; Reservoirs
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/j.cryogenics.2012.12.001

► A new configuration of a PTC with a cold reservoir at the cold end was proposed. ► The cooling performance of the new configuration can be significantly improved. ► The verification experiments with a home-made GM PTC were implemented. ► There is an optimal flow conductance ratio of the cold orifice to the regenerator. Phase difference between pressure wave and mass flow is decisive to the cooling capacity of regenerative cryocoolers. Unlike the direct phase shifting using a piston or displacer in conventional Stirling or GM cryocoolers, the pulse tube cyocooler (PTC) indirectly adjusts the cold phase due to the absence of moving parts at the cold end. The present paper proposed and validated theoretically and experimentally a novel configuration of PTC, termed cold reservoir PTC, in which a reservoir together with an adjustable orifice is connected to the cold end of the pulse tube. The impedance from the additional orifice to the cold end helps to increase the mass flow in phase with the pressure wave at the cold end. Theoretical analyses with the linear model for the orifice and double-inlet PTCs indicate that the cooling performance can be improved by introducing the cold reservoir. The preliminary experiments with a home-made single-stage GM PTC further validated the results on the premise of minor opening of the cold-end orifice.