Periodic flow hydrodynamic resistance parameters for woven screen matrices at cryogenic temperatures

Cryogenic Engineering Conference 2017

材料科学;物理学

Perrella, M.D.^1 ; Ghiaasiaan, S.M.^1

G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta

GA

30332, United States^1

关键词: Cryogenic temperatures;    Darcy permeability;    Hydrodynamic parameters;    Pulse tube cryocoolers;    Regenerator materials;    Temperature conditions;    Temperature models;    Thermal behaviours;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/278/1/012165/pdf
DOI  :  10.1088/1757-899X/278/1/012165

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

The regenerator is a critical component in all Stirling and Pulse Tube cryocoolers. It generally consists of a microporous metallic or rare-earth filler material contained within a cylindrical shell. Accurate modelling of the hydrodynamic and thermal behaviour of different regenerator materials is crucial to the successful design of cryogenic systems. Previous investigations have used experimental measurements at steady and periodic flow conditions in conjunction with pore-level CFD analysis to determine the pertinent hydrodynamic parameters, namely the Darcy permeability and Forchheimer coefficients. Due to the difficulty associated with experimental measurement at cryogenic temperatures, past investigations were mostly performed at ambient conditions and their results are assumed to be appropriate for cryogenic temperatures. In this study, a regenerator filled with woven screen matrices such as 400 mesh T316 stainless steel were assembled and experimentally tested under periodic helium flow at cryogenic temperatures. The mass flow and pressure drop data were analysed using CFD to determine the dimensionless friction factor, Darcy Permeability and Forchheimer coefficients. These results are compared to previous investigations at ambient temperature conditions, and the relevance of room-temperature models and correlations to cryogenic temperatures is critically assessed.