Discussion Forum

I am simulating a 2-D chamber containing water with no initial CO2 concentration and a headspace with the laminal flow of CO2 entering from the top. The CO2 flow enters the chamber with a normal flow velocity of Uin (m/s) and an inflow concentration of Cin (mol/m3). This laminar flow is going to reach the interface and then diffuse to the water. No mass transfer resistance is assumed at the interface. So, the interface reaches the equilibrium right away, obeying Henry’s law. The CO2 concentration is required to be tracked at each time in both water and headspace.

I am using the laminar flow module for the headspace and the Transport of diluted species module for both water and headspace. For the laminar flow module, the leaking wall is used as the boundary condition at the interface and the fluid velocity is set to the components of the velocity profile, (u,v).

For the Transport of diluted species modules, it is considered that the mass transfer in the headspace is done just by convection, setting the diffusion coefficient to zero, and in water by diffusion, setting the diffusion coefficient to D.

However, I am not sure about the boundary conditions at the interface for the Transport of diluted species modules. It should be in a way that considers both the convection (v*C) and Henry’s law, the jump of the concentrations at the interface.

Any suggestions and ideas are really appreciated!