Numerical Analysis of Regenerator and Stirling Type Pulse Tube Cryocooler

Abstract

For producing temperature up to cryogenic range the cryocooler is the most important device and the cryogenic regenerator is the vital part of a cryocooler. Pulse tube refrigerators are increasingly become popular in this generation due to its higher reliability, no moving parts in cold end, easy design and fabrication technique, less maintenance, less wear and tear etc. Regenerator is a device which transfers energy between two fluids flowing in same area by storing it in a matrix. It is compact in size and periodic type of heat exchanger in which the flowing fluid is always in direct contact with the solid heat transfer surface area.
The present work is directed upon the numerical analysis of regenerator and Stirling type Pulse tube cryocooler using commercial software ANSYS FLUENT. The wire mesh screen matrix is chosen as regenerator material. The 3D model of regenerator is created with suitable dimensions using WORKBENCH. Then, a numerical simulation is carried out to evaluate the performance of regenerator and analyse the fluid and heat flow characteristics of the regenerator.
The numerical work is further extended to study the performance of inertance type pulse tube refrigerator (ITPTR). The present work is carried out for single stage cryocooler. It consists of only one regenerator. This numerical analysis is done by varying the operating frequency. The fluid and heat flow characterstic variations in ITPTR are presented in the thesis.