In the present study, the accurate determination of the vapor phase pvTx behavior of binary mixtures of 1,1,1,2-Tetrafluoroethane (R134a) + 2,3,3,3-Tetrafluoroprop-1-ene (R1234yf) by using a Burnett apparatus was demonstrated. Measurements have been performed over the temperature range from (303 to 388) K and at pressures up to 5023 kPa covering the mole fractions of x_R134a = (0.000, 0.099, 0.328, 0.523, 0.726, 0.919, 1.000). The combined expanded uncertainties of temperature, pressure, mole fraction and vapor density with a level of confidence of 0.95 (k = 2) were estimated to be 24 mK, 1.6 kPa, 0.01 and within 0.2% over the entire temperature, pressure and mole fraction ranges, respectively. In order to facilitate practical industrial applications and explore the thermophysical behavior of the second and third virial coefficients, the experimental vapor density data of this work were used to develop the virial equation of state with the average absolute deviation of compressibility factor lower than 0.52% for each composition. Furthermore, the obtained gaseous pvTx properties of R134a/R1234yf mixtures were compared with the multi-parameter equation of state of REFPROP 10.0 (Lemmon et al., 2018) and the relative deviations were less than 1.2%.

在本研究中，使用1,1,1,2-四氟乙烷 (R134a) + 2,3,3,3-四氟丙-1-烯 (R1234yf) 的二元混合物的气相pvTx行为的准确测定演示了伯内特装置。已在 (303 至 388) K 的温度范围内和高达 5023 kPa 的压力下进行测量，涵盖x _R134a  = (0.000, 0.099, 0.328, 0.523, 0.726, 0.919, 1.000)的摩尔分数。温度、压力、摩尔分数和蒸汽密度的综合扩展不确定性，置信水平为 0.95 ( k = 2) 分别在整个温度、压力和摩尔分数范围内估计为 24 mK、1.6 kPa、0.01 和 0.2% 以内。为了便于实际工业应用和探索第二和第三维里系数的热物理行为，本工作的实验蒸汽密度数据被用于开发压缩系数的平均绝对偏差小于0.52%的维里状态方程。每个组成。此外，获得的 R134a/R1234yf 混合物的气态pvTx特性与 REFPROP 10.0 的多参数状态方程（Lemmon 等，2018）进行了比较，相对偏差小于 1.2%。