Measurement and Correlation of the Thermal Conductivity of 2,3,3,3-Tetrafluoroprop-1-ene (R1234yf) and trans-1,3,3,3-Tetrafluoropropene (R1234ze(E))

New experimental data on the thermal conductivity of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) are reported that allow the development of wide-range correlations. These new experimental data, covering a temperature range of (242 to 344) K for R1234yf and (203 to 344) K for R1234ze(E) at a pressure range of (0.1 to 23) MPa, are used to develop correlations for the thermal conductivity. The experimental data reported here have an uncertainty of less than 1 % for liquid measurements and for gas at pressures above 1 MPa, increasing to 3 % for gas at low pressures (less than 1 MPa). On the basis of the uncertainty of and comparisons with the present data, the thermal-conductivity correlations for R1234yf and R1234ze(E) are estimated to have relative expanded uncertainties of 3 % at a 95 % confidence level.