Hello users:
How does CFDEM calculate particles force on fluid cells?
As I understand , For calculating Drag force on particles we should at first obtain " inter-phase momentum transfer coefficient due to drag" which is shown in Kochhill drag by "betap".
As I saw in the papers , this parameter "betap" is used again when we want to obtain forces from particles on fluid cells. the question is that whether the existed solver consider this parameter ? If yes , How? from which Formula? If not, should I my own add the force from particle to fluid through source tern in momentum equation?
I know the forces from fluid on particles however I do not know how the forces from particle to fluids is applied in momentum equation "Ueqn".
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I saw the solvers and I found "ksl" coefficient. what does this coefficient mean and what is its application in momentum equation?
Is there any relation between ksl and particles force on fluid?
cgoniva | Wed, 08/20/2014 - 10:00
Hello,
Hello,
the drag on each particle is calculated (e.g. by Koch Hill drag law you mentioned) and used in the DEM simulations,
these forces are then summed up over all particles in a cell - this is stored in the Ksl field. Ksl*(Up-Uf) is then used in the momentum equation.
See more details for instance here: http://www.cfdem.com/forums/cite-cfdem-coupling
If you wanna go into details, you might be interested in the upcoming course: http://www.cfdem.com/media/downloads/flyer_course_DCS.pdf
Cheers,
Chris