Thermodynamic Properties Of The Seven Fluorine Propane (hfc-227ea)

According to the revisions of the Montreal Protocol, CFCs and HCFCs will be phased out. At the present, HFC-227ea(1, 1, 1,2, 3, 3, 3- Heptafluoropropane) isconsidered as a harmless refrigerants to ozone layer and a possible alternative refrigerant to replace CFC12 and CFC114, and blends containing HFC-227ea are potential alternatives to R22 and R502.MBWR(Modified Benedict-Webb-Rubin) equation of state was selected asthe pVT eqution of state for HFC-227ea. Based on pVT experimental data of HFC-227ea published in literature, we fitted a pVT equation of state for HFC-227ea, and determined the adjustable coefficients of the pVT equation for HFC-227ea. This equation is suitable for conditions of the pressure from 0.03MPa to 53MPa, density from 2.9kg/m3 to 1800kg/m3, and temperature from 204K to 473K. The average absolute deviations of this equation for gaseous phase pressure, vapor pressure and liquid density are 0.296%, 0.213% and 0.148%, respectively. And then according to the differential relationship of entropy, internal energy and enthalpy, pVT equation of state for HFC-227ea and the ralionship of specific heat, we deduced the calculation equation of thermodynamic properties(enthalpy, entropy ,specific heat)of HFC-227ea, calculated the enthalpy ,entropy, specific heat of HFC-227ea, and given pressure-enthalpy chart(p-H chart, temperature 245-455K, pressure 0.03-10MPa, density 2-1500kg/m3), temperature-entropy chart(T-s chart, temperature 235-450K, pressure 0.0015-20MPa, density 0.2-1400kg/m3), specific heat at constant pressure graphical chart(C_p-T chart, temperature 280-460K, pressure l-5MPa) of HFC-227ea. We described some thermodynamic properties over the entire thermophysical surface.