Evaluation on Excess Entropy Scaling Method Predicting Thermal Transport Properties of Liquid HFC/HFO Refrigerants

Abstract

The application of the excess entropy scaling (EES) method to predict the viscosity, thermal conductivity and thermal diffusivity of HFC/HFO refrigerants is evaluated in this paper. The universal coefficients of the EES model were firstly obtained from the properties of HFC refrigerants, and the accuracy of the model was further investigated with HFO properties. It was suggested that the EES model correlated the viscosity very well with the average absolute deviations (AADs) of most HFC refrigerants lower than 6.55% except R32. The correlations also provided very good prediction on the viscosity for R1234yf and R1234ze(E), but not for R1336mzz(Z). The prediction of thermal conductivity for both HFC and HFO refrigerants was generally well with the maximum AAD of 11.44%. However, the paper also indicated that there were no universal thermal diffusivity coefficients for even HFC refrigerants, and the linear function could not fit the thermal diffusivity curve very well. Therefore, the exclusively two-order polynomial correlations based on the EES model were presented for each HFC/HFO refrigerant.