The different rates of change of density and viscosity in going from the dilute gas to the dense fluid state give rise to kinematic viscosities that, in the slightly supercritical region, are exceptionally low. As a consequence, the ratio of buoyant to inertial forces is more than two orders of magnitude higher than in ordinary liquids at any given Reynolds number, and natural convection often controls the rate and mechanism of mass transfer. Experiments were designed to measure true diffusion coefficients (in the absence of buoyancy effects) as well as apparent diffusion coefficients (under the influence of variable buoyant forces), and significant differences were observed. Hydrodynamic behavior is approached at high pressure, and provides a useful framework for data analysis, correlation and extrapolation.
|Title of host publication
|Supercrit Fluid Technol
|Elsevier (Process Technol Proc v 3)
|Number of pages
|Published - 1985
All Science Journal Classification (ASJC) codes
- General Engineering