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Reply To: Boundary conditions for waterAirflatInterface2d

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Hi Callum,

I want to emphasize again, that this model for thermodynamic multicomponent multiphase mixtures has been introduced to OpenLB without boundary conditions as you can see from the example cases. Even for the inlet, it might need extra work to have a functioning velocity boundary condition. E.g. how does the pseudopotential force work on your bc as there will be some neighbouring nodes that are missing? Or as this model has density ratios, how do you determine the density at the inlet, it needs to be set as well as the velocity as in these multiphase models the density is not uniform everywhere.

If you would just like to have a simulation with water and air without the exact thermodynamics, you could also have a look into the free surface models. They are easier, but have the drawback that you only solve the momentum equation for the liquid. In the future, there will be high density ratio phase field models in OpenLB, too, with which it will be possible to simulate water-air systems too (without the mixture thermodynamics though).

Kind regards