Theoretical And Experimental Study On Thermodynamic Properties Of Fluoroethane And Its Mixture Refrigerants

According to the revisions of the Montreal Protocol, HCFCs will be phased out. At present, the research on the alternative refrigerants is very active in the world. The study on the thermodynamic properties of alternative refrigerants, especially pvTx properties, is not only very important to choose the most promising alternative refrigerants, but also to the study of thermophysical properties. Fluoroethane (HFC-161, C₂H₅F) is considered as a promising refrigerant, especially as an important component of the mixture (HFC-161/125/32) to replace HCFC-22. The researches on thermodynamic properties of HFC-161 and its mixture refrigerants, including accurate experiments of thermodynamic properties and theoretical analyses, are introduced in this dissertation.The measurement system for pvTx properties of refrigerants with high accuracy was developed. It consists of a temperature measurement (range: -40-300℃, tempeature uncertainty less than ±14 mK), a pressure measurement (range: 0-6.0 MPa, pressure uncertainty less than ±1.3 kPa), a thermostat bath (range: -40-180℃), a vacuum system, a mixture make-up system, etc.The vapor pressure of HFC-161 was measured with temperatures ranging from the normal boiling point to the critical point, and a vapor pressure equation of HFC-161 was developed. The normal boiling point and acentric factor were also determined.The gaseous and supercritical pvT properties of HFC-161 were measured using the isochoric method. The new correlations of saturated vapor and liquid densities were developed in a wide temperature range.An equation of state in Helmholtz free energy for HFC-161 was proposed with temperatures ranging from the triple point to 413.29 K, and pressures up to 5.8 MPa, which can be used to cover the experimental data in all fluid phases, and capable of representing all the updated measurements of thermodynamic properties precisely. The derived properties can also be calculated correctly from this equation of state. The formulas of thermodynamic properties calculation, and the saturated enthalpy and...