A simple generalized equation for compressed liquid isochoric heat capacity of pure and mixture refrigerants

This work aims to develop a generalized equation for compressed liquid isochoric specific heat capacity (c _v ). The form of the equation was proposed based on the isochoric specific heat capacity calculation equation derived by the Peng-Robinson equation of state. The generalized coefficients were determined by 1734 liquid experimental c _v data from 17 refrigerants. With known critical point, acentric factor and idea gas isochoric specific heat capacity, the developed equation can represent the liquid c _v of 17 refrigerants well with the average absolute relative deviation of 1.55%. Large deviations are most likely to appear near the critical point. Comparisons were made to the calculation deviations from the Peng-Robinson equation of state and the multiproperty equations in REFPROP 9.1 software. It indicates that the developed equation provide a simple and reliable method for the calculation of the liquid c _v . Additionally, 9 mixture refrigerants were calculated by the proposed generalized equation with the average absolute relative deviation of 3.13%.