PROPERTIES OF PURE REFRIGERANTS AND REFRIGERANT MIXTURES FROM CUBIC EQUATIONS OF STATE

摘要

Vapour-liquid equilibrium, thermodynamic and volumetric properties were predicted for three pure hydrofluorocarbons (R32, R125 and R134a) as well as for binary and ternary mixtures of these refrigerants. Five cubic equations of state; GEOS3C (general cubic equation of state with 3 constants), SRK (Soave - Redlich - Kwong), PR (Peng - Robinson), SW (Schmidt-Wenzel) and C-l (Freze et al.) were used. A wide comparison with literature experimental data was made. For the refrigerant mixtures, classical van der Waals mixing rules without interaction parameters were used. The GEOS3C equation, with three pure component parameters estimated by matching several points on the saturation curve (vapour pressure and corresponding liquid volumes), compares favorably to other equations in literature, resting simple enough for applications.