prediction of conductivity coefficient for fluorocarbon refrigerants r11, r22 and r32 by cubic equations

Today, due to the industrial activities and applications that coolers and refrigerants play in industry as well as homes, having a suitable refrigerator with suitable physical conditions that is appropriate to the needs and applications is very necessary. in this regard, knowing and obtaining the correct physical properties of a refrigerant with appropriate accuracy is very important, in this field, many experimental methods have been introduced, but the method of using cubic equations with two terms of molecular attraction and repulsion to obtaining the physical properties of various compounds has been widely used in recent years. in this article, we have tried to use the pr equation of state as the basis of the model and change it as the tpk model to obtain the thermal conductivity coefficient of refrigerants with high accuracy. among the refrigerants studied, the relative error of r-22, which was 0.042%, was the lowest error and r-11 was 0.192%, the highest error. the rate of deviation and absolute error in these two materials is 1.39 and 2.45 degrees in all ranges of points used. in this method, in order to obtain the best coefficients for each of the selected refrigerants, the fminsearch optimization algorithm, which is a local optimization algorithm, obtains the minimum amount of the specified objective function in the requested region.