Forty-four vapor pressures of Refrigerant 152 a (CH3 CHF2 : 1, 1-difluoroethane) between 273 and 386 K were measured in the range of pressures from 0.26 to 4.48 MPa. Ten saturated liquid densities and eleven saturated vapor densities near the critical point were also measured in the range of temperatures from 370 K to the critical temperature which corresponds to a density variation of 153 to 635 kg·m-3. The experimental uncertainties of temperature, pressure and density measurements were estimated within ±10 mK, ±0.8 kPa and ±0. 55 %, respectively. On the basis of these results, the critical temperature, critical pressure and critical density of R 152 a were determined to be 386.44 K, 4.5198 MPa and 368 kg·m-3, respectively, in consideration of the meniscus disappearing level as well as the intensity of the critical opalescence. In addition, the correlation of vapor pressure and that of the vapor-liquid coexistence curve were also proposed.
|Number of pages||7|
|Journal||Transactions of the Japan Society of Mechanical Engineers Series B|
|Publication status||Published - 1987|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanical Engineering