Free Surface Flows of Non-Newtonian Fluids
 

What are the best tools for this?
The problem is extrusion of a few cubic centimeters of hydrogel and attachment to a surface (time scale = 30-120seconds).
Axi-symmetry assumption may be necessary.
Surface tension forces would be nice but could be ignored initially.
Non-Newtonian means fluid with elasticity not just shear dependent viscosity.
A challenge indeed! :eek:

Yes a challenge indeed, but slowing working on it as I get time. :-D

Extrusion is one of the application in my mind.

Extrusion < Attachment
 

The extrusion process is important but well analyzed in the literature (see 30year old work by Phan-Thien and Tanner with BEM). I have a lot of information there. The attachment process including adhesion, spreading, deformation and detachment from the extrusion needle are much less studied.

One approach is to assume axisymmetry and use a BEM formulation reducing the 3D problem to a 1D (also assuming negligible inertial terms). But the viscoelastic terms still need a volume grid to be determined. Small inertial effects could be also considered as a first order pertubation (using the same volume grid).

Thoughts?