viscous contribution in flow engine

Hello,

I want to model the undrained triaxial compression of a suspension (relatively dense).
I want to use the PFV model from oedemeter.py.
Shear may not be dominant in my case however in order to deal with viscous effects (shear stresses),
Marzougui et al 2015 introduced indeed lubrication forces on particles in the PFV model: is this not taken
 into account in special cases in the flow engine in yade or i have to add special "lubrication" interactions
 between particles ?? (if it exists).

Best,

Fr.