Key words: thermal gravity-driven convection, thermodynamic critical point, adiabatic heating (piston effect), stratification, adiabatic temperature gradient
Common features of gravity-driven convection near the thermodynamic critical point are considered. Abnormal physical properties of supercritical fluids (unbounded growth of specific heat at constant pressure and coefficients of isothermal compressibility and thermal expansion, tending to zero of thermal diffusion coefficient while approaching to the critical point) cause peculiarities in convective flows and heat transfer. Hydrodynamic behavior of supercritical fluids is influenced by the density stratification and characterized by intensification of internal motions, reduction of convection space scale, forming the piston effect, existence of multiple time scales in dynamic and heat processes.
doi:10.1134/S1990793114080132