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At present, the difficulty in the research of auto cascade refrigeration system lies in the selection of the mixed refrigerant ratio and the design of system process. Accurate thermodynamic data is the key to solve those problems. In this paper, isothermal vapor liquid equilibrium (VLE) behavior was experimentally studied for the strongly-zeotropic ternary mixture 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) + trifluoromethane (R23) + tetrafluoromethane (R14) at 253.15 K, 263.15 K, and 273.15 K. The pressures and the vapor mass fractions were found to be thermodynamically consistent and were satisfactorily correlated with the NRTL-RK model and the MUNIFAC-SRK model. The average absolute relative deviations of pressure (AARD- p), and the average absolute deviations of vapor phase mass fraction (AAD- y 1 , AAD- y 2 and AAD- y 3) are less than 0.25%, 0.0032, 0.0048 and 0.0040 for the MUNIFAC-SRK model, respectively, which are better than those of 0.4%, 0.0138, 0.0198 and 0.0049 for the NRTL-RK model. The results of the MUNIFAC-SRK model showed excellent agreement with the experimental values. The isothermal three-dimensional VLE behavior and the isothermal-isobaric ternary VLE diagrams under 1500 kPa were also established using a flash calculation method. [ABSTRACT FROM AUTHOR]

Highlights • A counter flow dew point evaporative cooling system is developed and investigated. • 1D and 3D models of the heat and mass transfer in the cooling system are developed. • On average, the 1D model temperature predictions are 1.86% lower than the 3D model. • The 3D and 1D models predict experimental results within 8.5% and 10%, respectively. • The cooling system can reach wet-bulb effectiveness values as high as 125%. Abstract In this study, the performance of a counter flow dew point evaporative cooling system has been examined, numerically and experimentally. A one-dimensional (1D) model of the heat and mass transfer in the cooling system is presented. In order to assess the 1D model, a detailed three-dimensional (3D) model is developed. Experimental results showed that the wet-bulb effectiveness of the cooling system could reach values as high as 125%. The predicted variations of air temperature along the channels of the cooling system by both models are in fair agreement. On average, the 1D model predicts lower outlet temperatures by about 1.86% relative to the 3D model. While the computational time of the 3D model is about three orders of magnitude higher than the 1D model. The predicted outlet temperature of the cooling system by the 1D and 3D models match the experimental results within 10% and 8.5%, respectively. [ABSTRACT FROM AUTHOR]