Hi, I would like to impleme
 

Hi,

I would like to implement a boundary condition for thermocapillary convection. Pardon my ignorance - but I am wondering if (what..) difference it would make if I consider it a momentum source somehow like

S=dT/dz*dG/dT*A/V

with T=Temperature, z =coordinate parallel to surface, A=area of a surface element, dG/dT dependency of surface tension on temperature, and V = Volume of the volume cell adjacent to the surface element

or as a fixed gradient condition:

mu* dU/dn=dG/dT*dT/dz

mu=viscosity, dU/dn velocity gradient perpendicular to surface

Thank you very much for any hint !