Experimental studies of thermoacoustic drive for the development of a pulse tube cryocooler

Abstract

Thermoacoustically driven Pulse Tube Cryocooler (PTC) totally eliminates the moving components and is totally reliable towards cryogenic applications. In an objective to development of such a system, we need to design the Thermo Acoustic Prime Mover (TAPM) to drive the Pulse Tube cryocooler. We have made detailed design of the standing wave twin TAPM using the simplified linear thermoacoustic model of short stack and boundary layer approximations, based on the procedures outlined by Swift [1] and Tijani [2]. The theoretical design indicates the dependence of the system performance on stack geometry and its relative position with respect to other components for different working fluids. Based on the above design, the TAPM with different resonator lengths were fabricated and experimented. Studies have been conducted to evaluate their performance characteristics with respect to several parameters such as the resonator length, the working fluid and the operating pressure. The optimized TAPM has been used as the prime mover for a single stage Pulse Tube Cryocooler. A temperature difference of ~42 K has been measured between the hot and cold ends of the Pulse Tube. These results are presented here.