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Ideal design and precise analysis of refrigeration processes require accurate knowledge of the thermophysical properties of the involved fluids. Design calculations and process analysis are typically carried out considering only the working fluid, i.e., the pure refrigerant or refrigerant blend, which is usually ‘contaminated’ with the lubricant oil of the compressor. The oil affects the properties of the working fluid by shifting the evaporation temperature, density, and especially viscosity. Due to the difficulty in modeling all required thermophysical properties (mainly: density, heat capacity, entropy, enthalpy, viscosity, and thermal conductivity) of oils and oil-refrigerant mixtures, analysis of refrigeration processes considering the refrigerant being mixed with oil remains a challenge today. Recently, we have developed a novel modeling approach that requires less than 20 experimental data points to develop a model set for all required properties of an oil, and one additional mixture data point to predict the properties of an oil-refrigerant mixture. Here, we present the application of this modeling approach to the thermo-economic analysis of refrigeration machines and compare it to only considering pure refrigerant. A software package is being developed for such an analysis, the main components of which, a fluid properties package and a simple process analysis, have already been completed. The subsequent step is to implement the software package to process simulation software, such as DWSIM or EBSILON Professional.

Schlagwörter: Design, Lubricant, Mixture, Refrigerant, Viscosity, Software