about coupling intervals

Submitted by openfoam on Wed, 12/12/2012 - 14:50

I'm a new cfdem user, about coupling intervals, I have several questions:

1. How to calculate its value?
2. In the DEM/in.XXX file, there is a command about coupling:
fix cfd all couple/cfd couple_every n mpi
what's the relationship between coupling intervals and value n. They are equivalent ?
3. The meaning of coupling intervals, I think it's:
run CFD $couplinginterval and then run DEM, the DEM step number defined in "run n" command in in.XXX file.
Is there anything wrong?

Thanks anyway,
Zhao