HFC-125气相声速和理想气体比定压热容的研究

Study on speed of sound and ideal-gas heat capacity at constant pressure for HFC-125

分析了气相声速与理想气体比定压热容的热力学关系 ,用超声变程干涉仪测定了HFC -12 5的 4 9组气相声速值 ,温度范围 2 73- 313K ,压力范围 32 - 4 79kPa。根据这些实验数据 ,获得了HFC - 12 5的理想气体比定压热容和声速第二维里系数 ,并分别拟合得到了理想气体比定压热容和声速第二维里系数与温度的函数关系。使用方阱势能模型导出了HFC - 12 5的第二维里系数 。

Based on thermodynamics, the relationship between thermodynamic parameters and gaseous speed of sound was analyzed. A total of 49 data points of speed of sound for gaseous HFC-125 were measured for temperatures from 273 to 313 K and pressures from 32 to 479 kPa with a cylindrical, variable-path acoustic interferometer. The ideal-gas heat capacity at constant pressure and the second acoustic virial coefficients were determined over the temperature range from the speed of sound measurements and correlated their functions with temperature. The second virial coefficients were derived by the square-well potential model and compared with available data.