Thermodynamic Properties of Propane. III. A Reference Equation of State for Temperatures from the Melting Line to 650 K and Pressures up to 1000 MPa

An equation of state is presented for the thermodynamic properties of propane that is valid for temperatures from the triple point temperature (85.525 K) to 650 K and for pressures up to 1000 MPa. The formulation can be used for the calculation of all thermodynamic properties, including density, heat capacity, speed of sound, energy, and saturation properties. Comparisons to available experimental data are given that establish the accuracy of calculated properties. The approximate uncertainties of properties calculated with the new equation are 0.01 % to 0.03 % in density below 350 K, 0.5 % in heat capacities, 0.03 % in the speed of sound between (260 and 420) K, and 0.02 % in vapor pressure above 180 K. Deviations in the critical region are higher for all properties except vapor pressure.