Development of inline high frequency miniature pulse tube crycryocooler for 80 K applications

In today's world, miniaturization is the buzz word. It is not only the production of low temperatures that is important, but also the size of the equipment. It is imperative that a Pulse Tube Cryocooler must be operated close to its resonance frequency to deliver an optimum performance. Increasing the resonance frequency of a system not only decreases the cool down time but also the overall size of the system. However, the viscous dissipation losses become more and more predominant at higher frequencies. The present paper reports the development of High Frequency Pulse Tube Cryocooler operating at 148 Hz. The total pulse tube - regenerator volume of this system is as low as 1.72cc. A low temperature of 90 K is obtained in less than 5 minutes while the no load temperature of the system is 86 K. The experimental investigations aimed to study the performance dependence on the operating and dimensional parameter changes. The operating parameters include variation in charging pressure, frequency. The dimensional changes include variations in the lengths of inertance tube, pulse tube and regenerator.