which force is included in the momentum transfer

Submitted by rqwang on Mon, 11/12/2012 - 05:41

Hi,

May I ask a question about the momentum transfer between solid and fluid phases?

Where can I specify the range of the forces included for momentum transport from solid phase to fluid?

Is MeiLift included? Could anyone give me a clue?

Thanks.

rq

alice's picture

alice | Mon, 11/12/2012 - 09:09

Hello,
the user can choose amongst a number of force models implemented (oen of which is the MeiLift model). You can find them at src/lagrangian/cfdemParticle/subModels/forceModels. If you want to use one of them, you have to indicate it by adding the keyword to the couplingProperties dict in the CFD/constant folder of your case.
Cheers,
Alice

rqwang | Mon, 11/12/2012 - 14:37

Hi Alice,

Thank you for your reply. My question was what force will be transferred from dem to cfd. At last, I realized in the source code of the force model, treatDEM = false means the force will be transferred and =true means not.

Thanks.

rq

cgoniva's picture

cgoniva | Tue, 12/04/2012 - 13:31

Hi,

there is no force transferred from DEM to CFD -
particle data is transferred from DEM to CFD - drag/lift is calculated and transferred to DEM and used in the CFD momentum balance. By default most (drag)forces have treatImplicit=true; meaning it comes to the Ksl term and to the DEM. if you set treatDEM=true; it should only be considered in the DEM. (in doubt, please have a look at the code to be sure)

Cheers,
Chris