Definition of Wall Surface Properties?
 

Hi all,

I am currently attempting to model a simple/fun project to test capabilities. I have a "blob" of peanut butter in a cup inclined at 45 degrees and I am rotating the cup at 1 rad/s. The AMI patches are located at the centre of the cup with the outer region rotating.

However, when I simulate this, the peanut butter does not intuitively stick to the side of the cup and rotate all the way round with the wall, but remains at the bottom of the cup. Furthermore, the peanut butter seems to be flowing more than one would expect. The figure below illustrates the problem;

Attachment 57979

I had wondered whether this is anything to do with the definition of the wall properties of the cup? For example, I haven't found a way to define surface roughness which would aid adhesion to the cup wall as one would imagine in reality.

I've modelled a similar case using paddles to disrupt the fluid. In this case, the fluid seems to stick to the paddles and is dragged around the domain as expected - as shown below;

Attachment 57978

What skews my understanding of this problem is that I had previously simulated a 3D dam break (using ketchup!) and, while the bulk of the material falls quickly to the ground, the fluid close to the wall falls much more slowly, seemingly adhering to it.

Has anyone any thoughts on this? I've simplified my mesh and attached the case below if anyone is able to have a quick look, I'd be very grateful!

https://drive.google.com/open?id=0B3...jJkY1puUVl5eWc


Best regards,