Pressure boundary in transient simulation
 

Hi All,

I am modelling a stirred tank using the SG approach. I get a message in the solver output that " WARNING: TRANSIENT GRIDDING OPTION BEING USED WITHOUT A PRESSURE BOUNDARY, THE FLOW HAS TO BE DEFINED CAREFULLY TO ENSURE MASS CONSERVATION".

Yes, I had reported in the earlier posting that I had problems with mass conservation of a tracer.

I have define the top of the tank as no slip wall (free surface). Now, where am I supposed to define this pressure boundary?

Thanks for your time. Nyatoto