The gaseous speed of sound, the ideal gas heat capacity at constant pressure, and the second Virial coefficient were determined for pentafluoroethane (HFC 125). A total of 49 data points of speed of sound for gas...The gaseous speed of sound, the ideal gas heat capacity at constant pressure, and the second Virial coefficient were determined for pentafluoroethane (HFC 125). 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 coefficient were determined over the temperature range from the speed of sound measurements and were correlated as functions of temperature. An analytical expression for the second Virial coefficient derived using the square well intermolecular potential model was compared with the data.展开更多
The speed of sound of the gaseous difluoromethane (HFC-32) and trifluoroiodomethane(CF3I) are measured with a cylindrical, variable-path acoustic interferometer operating at156.252 kHz. Temperatures ranged from 273.15...The speed of sound of the gaseous difluoromethane (HFC-32) and trifluoroiodomethane(CF3I) are measured with a cylindrical, variable-path acoustic interferometer operating at156.252 kHz. Temperatures ranged from 273.15 K to 333.15 K for both and pressures rangedfrom 48 kPa to 390 kPa for HFC-32 and from 58 to 276 kPa for CF3I, respectively Theuncertainty of the speed of sound was less than ±0.1%. The ideal-gas heat capacity atconstant pressure and the second acoustic virial coefficients for HFC-32 and CF3I werealso determined over the temperature range from the speed of sound measurements. Theideal-gas heat capacities at constant pressure and second virial coefficients calculated fromthese speed of sound measurements for both were compared with results from the literaturedetermined from PVT measurements and from speed of sound measurements, respectively.The uncertainty of the ideal-gas heat capacities at constant pressure were estimated to beless than ±1%.展开更多
基金Supported by the National Natural Science Foundation of China( No. 5 990 60 0 6)
文摘The gaseous speed of sound, the ideal gas heat capacity at constant pressure, and the second Virial coefficient were determined for pentafluoroethane (HFC 125). 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 coefficient were determined over the temperature range from the speed of sound measurements and were correlated as functions of temperature. An analytical expression for the second Virial coefficient derived using the square well intermolecular potential model was compared with the data.
文摘The speed of sound of the gaseous difluoromethane (HFC-32) and trifluoroiodomethane(CF3I) are measured with a cylindrical, variable-path acoustic interferometer operating at156.252 kHz. Temperatures ranged from 273.15 K to 333.15 K for both and pressures rangedfrom 48 kPa to 390 kPa for HFC-32 and from 58 to 276 kPa for CF3I, respectively Theuncertainty of the speed of sound was less than ±0.1%. The ideal-gas heat capacity atconstant pressure and the second acoustic virial coefficients for HFC-32 and CF3I werealso determined over the temperature range from the speed of sound measurements. Theideal-gas heat capacities at constant pressure and second virial coefficients calculated fromthese speed of sound measurements for both were compared with results from the literaturedetermined from PVT measurements and from speed of sound measurements, respectively.The uncertainty of the ideal-gas heat capacities at constant pressure were estimated to beless than ±1%.
