Thermodynamic properties of the R-415A refrigerant in the vapor phase and on the condensation line

The speed of sound in the R-415A refrigerant vapor and its density and pressure on the condensation line were measured by the ultrasonic interferometer and constant-volume piezometer methods within a range of temperatures from $293$ to $373\text{ K}$ and pressures from $0.04$ to $0.5$–$2.45\text{ MPa}$. The temperature, pressure, density and speed of sound measurement errors were $\pm20\text{ mK}$, $\pm4\text{ kPa}$, and $\pm(0.1$–$0.2)\%$, respectively. The temperature dependence of the ideal-gas heat capacity was calculated on the basis of the obtained data. The obtained results were compared with the properties calculated by the REFPROP software.