Isobaric Heat Capacity Measurements of Supercritical R1234yf

R1234yf
(2,3,3,3-tetrafluoropropene) is a low global warming potential
(GWP) replacement for R134a, a fluid commonly used as a refrigerant
in domestic and automotive air conditioning systems and as a working
fluid in organic Rankine cycles. The use of R1234yf in energy conversion
cycles requires an accurate determination of its thermophysical properties,
including the isobaric heat capacity (cP). Using a custom-made flow calorimeter, experimental cP measurements of supercritical R1234yf were made at temperatures T = 373.15 to 413.5 K and absolute pressures P = 3.5 to 10 MPa. The experimental apparatus was calibrated using
R134a to increase the measurement accuracy. The heat capacity measurements
of R1234yf were compared to available published experimental data
and to values obtained from a multiparameter equation of state (EOS).
The measured cP values agreed well with
the EOS, providing an average absolute deviation (AAD) of 1.6%.