Nonnewtonian fluid modeling
 

Hi all,

I am trying to model ice-cream flow in a branched ducts using Fluent. Ice cream is a viscoelastic substance. Do I need to model it as a viscoelastic fluid and use Polyflow or is it enough to model it with a generalized nonnewtonian model when the case is steady state and I am interested in the flow rates rather than in accurate velocity flow fields representation? I have learnt that high Weissenberg number can be the reference to this distinction but I couldn't find any information what is high We number. Do you have any sugestions about it and how do I choose a proper time scale to calculate the We number? There is a high slip velocity on the wall. Therefore do you have any suggestions about asignig wall boudary conditions? I have found that problems with convergence occur when switching into no-slip wall bc's for 3D case.

Regards, Adam