coupling issues between the CFD code and DEM code

Submitted by leflix on Thu, 08/11/2011 - 12:32

Does any one here know how the coupling between the CFD code and the DEM code is done?
I mean, first one have to compute fluid velocity and pressure accounting from volume fraction through mass conservation and momentum equations.
This operation is generally processed by a velocity-pressure coupling algorithm like SIMPLE, PISO, Chorin projection, etc....
Does someone have some insights on this process and specifically how the mass conservation equation accounting the volume fraction is used for this purpose?

cgoniva's picture

cgoniva | Thu, 08/11/2011 - 14:04

Hello leflix,

the equations to be solved (modified NSE, similar to those for porous media) are written in:
system/files/CFDEM_currentState_Goniva_0.pdf slide 10.

Cheers,
Chris

leflix | Sat, 08/13/2011 - 12:26

Thanks Chris, but the problem is not how the modified NS equations are derived it's true that you can find them in many papers and I perfectly know them.
But what is never explained is how the velociy-pressure coupling algorithm (SIMPLE, PISO, Projection method etc...) is derived from these equations and especially the treatment of the temporal term of the mass conservation equation.
I would need some insights on this specific topic: the velocity-pressure coupling algorithm.

Thanks a lot.

cheng1988sjtu | Mon, 11/12/2012 - 19:10

The mass conservation term is implicitly implemented in the pressure step, that's why you see ddt(voidfraction) in p-equation.

C.Z. U of D

Oliver.pasqual | Sun, 10/07/2012 - 11:26

dear export,
I want to model a porous plate in the fluidized bed. few information has been captured after searching this topic on the forum.
through reading the pdf material you given, few insights attack me on how to modify the coupling code under the framework of CFD-DEM.
could you give me some suggestions on the modification for the coupling procedure of this topic?
Great Thanks!
o.p

cgoniva's picture

cgoniva | Mon, 10/22/2012 - 16:13

Hi,

there should be plenty of information on modelling porous media in the cfdonline forum. These approaches should also work in cfdem.

Cheers,
Chris

cgoniva's picture

cgoniva | Fri, 08/12/2011 - 07:59

There are many publications on unresolved CFD-DEM,
e.g. the group of JAM Kuipers:
Link et al. Flow regimes in a spout-fluid bed:A combined experimental and simulation study ,

or publications of Zhou and Zhu
e.g. Discrete particle simulation of particulate systems: Theoretical developments

Cheers,
Chris