Interaction between stl mesh wall in DEM and water in CFD

Submitted by Rachel on Tue, 11/14/2017 - 20:19

Dear all,

When I applied cfdemPisoSolver in my simulation, I found there is no interaction between stl mesh wall in liggghts part and water in openFoam part. Now, I am wondering whether there exist a method to define the contact betwwen water and walls?

In other words, if I want to simulation a similar problem about the drop process of a container full of water, how to define the interaction between water and the container? Is there any method? Any suggersions or clues are appreciated!

Best regards,
Rachel

Forums:

medvedeg | Wed, 11/15/2017 - 11:07

Hallo Rachel,

walls in LIGGGHTS (stl mesh) and walls on CFD side exist separately. For water you have to create a CFD mesh and define appropriate boundary conditions for every field (U,p, etc.) in CFD/0 folder.

Alexander Podlozhnyuk

Rachel | Wed, 11/15/2017 - 17:16

Hello, thanks for your reply. Yes, as I know in the CFD part, we can define the boundary conditions in CFD/0 folder, while do you know how to define the moving boundary conditions? Such as when we drop a bottle of water, the bottle may expericnece some displacements and will influence the water field, how to realize the function of moving boundary condiitons in CFDEM modelling? Many thanks.

Rachel

paul | Thu, 11/16/2017 - 21:16

There is a substantial difference between a "moving boundary" and "motion/velocity at a boundary".

The first is a very difficult problem AFAIK not possible compatible w/ CFDEM as here the mesh is actually moving/deforming.
The second is what Alexander referred to. If you do not understand, please have a look at the OpenFOAM user guide (esp the cavity case) where this is explained in detail.

CFDEMcoupling really works well in cases where your simulation domain is fixed (static mesh - rotating mesh is paid only AFAIR) and you want describe particulate motion depending on flow and vice versa. Nothing more (okay, maybe heat transfer) and nothing less. Everything else would require a lot of development work.