Dispersion coefficient
in 1D, accounts for macroscopic 2D convective motion of fluid elements (due to gas sparging) ~ 0.1 $m^2/s$.
- this motion of the fluid is confined to the limits of the domain, and T solved in the liquid phase can't escape the system by dispersion:
- --> $J_{T_2,disp}|_{\partial \Omega}=0$ (Neumann BC)
Diffusion coefficient
accounts for microscopic brownian motion of T particles in the fluid ~ $10^{-9} m^2/s$
- T can escape the system by diffusion. We could use a Robin BC
- --> $J_{T_2,diff}|_{\partial \Omega} = h_l c_T$
Dispersion and diffusion fluxes are both modelled by a Fick's law, which corresponds to a second order term on the T concentration in the equations.
When sparging is ON, dispersion clearly dominates -> no need for Robin BC for the moment, but could be nice to implement in the futur
Dispersion coefficient
in 1D, accounts for macroscopic 2D convective motion of fluid elements (due to gas sparging) ~ 0.1$m^2/s$ .
Diffusion coefficient
accounts for microscopic brownian motion of T particles in the fluid ~$10^{-9} m^2/s$
Dispersion and diffusion fluxes are both modelled by a Fick's law, which corresponds to a second order term on the T concentration in the equations.
When sparging is ON, dispersion clearly dominates -> no need for Robin BC for the moment, but could be nice to implement in the futur