Optimum mixture composition
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.
KeywordsHeat Exchanger Design Variable Heat Load Mixture Composition Exergy Efficiency
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