Negative Total Fluid Mass Source - VOF
 

Hi, I'm me too interested to use a negative "Total Fluid Mass Source" in my VOF simulation to let out air from my mold for the glass forming. I'using a VOF omogeneous model. How I can let out only air from the wall rather than the glass, which must to touch the walls of the mold to cool down without going out too? Is necessary to use a non omogeneous VOF model? In this last case how can I calculate the correct Cd between air and glass? Is it possible set another option to avoid the specification of the Cd?

Thank you