Construction of Joule Thomson inversion curves for mixtures using equation of state

26th International Cryogenic Engineering Conference & International Cryogenic Materials Conference 2016

材料科学;物理学

Patankar, A.S.^1 ; Atrey, M.D.^1

Indian Institute of Technology Bombay, India^1

关键词: Gas liquefaction cycle;    Inversion temperature;    Joule-Thomson coefficient;    Joule-Thomson cryocoolers;    Joule-Thomson effect;    Joule-Thomson inversion curve;    Multi-component systems;    Peng-robinson equations of state;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/171/1/012086/pdf
DOI  :  10.1088/1757-899X/171/1/012086

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

The Joule-Thomson effect is at the heart of Joule-Thomson cryocoolers and gas liquefaction cycles. The effective harnessing of this phenomenon necessitates the knowledge of Joule-Thomson coefficient and the inversion curve. When the working fluid is a mixture, (in mix refrigerant Joule-Thomson cryocooler, MRJT) the phase diagrams, equations of state and inversion curves of multi-component systems become important. The lowest temperature attainable by such a cryocooler depends on the inversion characteristics of the mixture used. In this work the construction of differential Joule-Thomson inversion curves of mixtures using Redlich-Kwong, Soave-Redlich-Kwong and Peng-Robinson equations of state is investigated assuming single phase. It is demonstrated that inversion curves constructed for pure fluids can be improved by choosing an appropriate value of acentric factor. Inversion curves are used to predict maximum inversion temperatures of multicomponent systems. An application where this information is critical is a two-stage J-T cryocooler using a mixture as the working fluid, especially for the second stage. The pre-cooling temperature that the first stage is required to generate depends on the maximum inversion temperature of the second stage working fluid.