The isobaric heat capacity of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) at temperatures from (230 to 285) K and pressures up to 8 MPa using a new flow calorimeter

Abstract

In this paper, a new flow calorimeter was developed to measure the isobaric specific heat capacity (cp) of liquids. The uncertainties of temperature, pressure, and cp were estimated to be less than 11 mK, 0.02 MPa and 1.26%, respectively. The pure 1,1,1,2-tetrafluoroethane (R134a) was measured at temperatures from (230 to 285) K to quantitatively calculated the heat leakage at different temperatures. In order to verify the reliability of apparatus, the cp for R134a and difluoromethane (R32) were obtained at temperatures from (230 to 285) K and pressures up to 8 MPa. Measurements of R134a and R32 show good agreement with the reported data and the high-precision Helmholtz energy equations of state (EoSs). Finally, a total of 33 cp data for 2,3,3,3-Tetrafluoroprop-1-ene (R1234yf) were obtained at temperatures from (230 to 285) K and pressures up to 8 MPa. The presented cp data show good agreement with the published data and two Helmholtz energy EoSs developed by Akasaka et al. and Richter et al. with the average absolute relative deviations (AARDs) of 0.92% and 1.80%, respectively. The Helmholtz energy EoS developed by Akasaka et al. gives a better prediction performance for the cp of R1234yf at low temperature than the other EoS.