Pressure Wave Generator for a Pulse Tube Cooler

Abstract

This paper describes the concept of a pressure wave generator for a pulse tube cooler without the use of a mechanical compressor. To understand the basic mechanism, a work amplifier was fabricated and tested. It consists of a work input piston, a regenerator with heat exchanger on both sides, a work transfer tube, a resonator, and a work receiver. These five critical components are connected in series. The pressure wave is generated by the piston at the resonance frequency of the resonator. By heating the heat exchanger, which is located at the work transfer tube side of the regenerator, the input work from the piston is amplified through the regenerator and flows out from the work transfer tube due to the conversion of the heat flow into the work flow. This amplification mechanism makes it possible for the input work to be replaced by a part ofthe output work through the feedback line. Finally, it becomes a self-actuated pressure wave generator without any external input work.

This study mainly discusses the performance of each component to improve the total performance of the system. A simplified analytical method using the equivalent PV work and preliminary experimental results is also given.