Optimum mixture composition

  • Gadhiraju Venkatarathnam
Part of the International Cryogenics Monograph Series book series (ICMS)


The exergy efficiency of any mixed refrigerant process depends on the mixture’s constituents and their concentration. The exergy efficiency of MRC refrigerators will be high when a second liquid phase occurs in the evaporator. Liquid-liquid immiscibility is observed at low temperatures in multicomponent mixtures of nitrogen–hydrocarbon, fluorocarbon–hydrocarbon, fluorocarbon–hydrochlorofluorocarbon and fluorocarbon–hydrofluorocarbon refrigerants [34, 55, 87, 89]. This immiscibility can be exploited to obtain a near-constant temperature evaporation with mixtures, as shown in Figs. 3.4 and 3.6 with both binary and multicomponent mixtures.


Heat Exchanger Design Variable Heat Load Mixture Composition Exergy Efficiency 
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© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringIndian Institute of Technology MadrasChennaiIndia

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