Hi~ i have a question for drag force.
nowdays, i study a simulation flow about liggghts, especially, coupling with openfoam.
i want to find how to affect flow( liquid or gas) to particle. so, i look at files for coupling(fix_cfd_coupling.cpp, fix_cfd_coupling_force.cpp and so on)
I found a drag force add to orient force(f) in function post_force(int).
but i could not find how to calculate dragforce( fix_dragforce_->array_atom).
Where is this force calculated?
thx for read my question, with my odd(?) english.