Measurement of Anisotropic Hydrodynamic Parameters of Pulse Tube or Stirling Cryocooler Regenerators

• Main Authors: Cha, J S, Ghiaasiaan, S M, Desai, P V
• Format: Conference Proceeding
• Language: English
• ISSN: 0094-243X
• DOI: 10.1063/1.2202622

Pulse tube refrigeration (PTR) systems are often modeled as one-dimensional flow fields. However, recent computational fluid dynamics (CFD) - based investigations have shown that multi-dimensional flow effects can be significant in the regenerator of a PTR, especially when the aspect ratio of the regenerator is small. Anisotropic hydrodynamic parameters of regenerators are therefore needed for the realistic simulation of their multi-dimensional flow phenomena. In this paper we report on measurements of the lateral or radial permeability and Forchheimer's inertial coefficient of a widely used PTR regenerator filler. Using helium as the working fluid, steady-state pressure drops were measured over a wide range of flow rates in annular test sections that contained regenerator fillers. The aforementioned hydrodynamic parameters were then obtained by comparing the data with the results of CFD calculations that simulated the test sections and their vicinity. CFD simulations of the experiments were performed iteratively, whereby permeability and Forchheimer coefficient that brought about agreement between data and simulation results were calculated.