Isobaric heat capacities of R245fa and R236fa in liquid phase at temperatures from (315 to 365) K and pressures up to 5.5 MPa

摘要

Isobaric heat capacities of compressed liquid 1,1,1,3,3-pentafluoropropane (R245fa) and 1,1,1,3,3,3-hexafluoropropane (R236fa) were measured by scanning calorimetry. The experimental system basically consists of a calvet calorimeter (Setaram C80) and a pressure balance unit. A total of 55 data points for liquid R245fa and 52 data points for liquid R236fa were obtained at temperatures from (315 to 365) K and pressures up to 5.5 MPa. The uncertainties for the heat capacity of R245fa and R236fa were estimated to be (1.8 and 1.6)%, respectively. The experimental data was correlated to an empirical equation, the form of which was decided by stepwise fit method. The average absolute percentage deviations between the data points and the equation were (0.23 and 0.10)% for R245fa and R236fa. (C) 2015 Elsevier Ltd. All rights reserved.