Hi,
I work on a coupled air-heat-moisture model in building walls.
I use the Heat Transfer and Fluid Flow modules, with T and P as dependent variables, and a node for moisture transfer, with phi relative humidity as dependent variable.
On the boundary I need to write the following boundary condition :
-grad(phi)=0 if u.n >=0
phi=phi_0 if n . u < 0
It means that the iso-moisture lines are normal to the boundary when some air is flowing through it.
I know that I should use the weak formulation with the test() operator to write this boundary condition, but the COMSOL userguide doesn't helped me on for that.
I am wondering if somebody have already dealt with that and could share some experience.
C. Belleudy
I work on a coupled air-heat-moisture model in building walls.
I use the Heat Transfer and Fluid Flow modules, with T and P as dependent variables, and a node for moisture transfer, with phi relative humidity as dependent variable.
On the boundary I need to write the following boundary condition :
-grad(phi)=0 if u.n >=0
phi=phi_0 if n . u < 0
It means that the iso-moisture lines are normal to the boundary when some air is flowing through it.
I know that I should use the weak formulation with the test() operator to write this boundary condition, but the COMSOL userguide doesn't helped me on for that.
I am wondering if somebody have already dealt with that and could share some experience.
C. Belleudy