Dear lammps users,
In granular particles I set random diameter for each particle using this commands :
variable Diam atom random(a,b,c)
set region mybox diameter v_Diam
and I want to add fixed (all time) force for each atom using addforce or setforce by a formula which includes per atom diameter, is there any idea?
Best regards,
Dear lammps users,
In granular particles I set random diameter for each particle using this
commands :
variable Diam atom random(a,b,c)
set region mybox diameter v_Diamand I want to add fixed (all time) force for each atom using addforce or
setforce by a formula which includes per atom diameter, is there any idea?
the first idea that comes to my mind is that you should _at the very
least_ make some effort yourself. however, considering what you write
in your e-mail, it appears to me so blatantly obvious what you can do,
that i am surprised that you are even asking. i for myself would be
embarrassed to ask for how to access a property in a variable, that
you have just set yourself *from* a variable.
axel.
Judging that you were the same guy asking about the Archimedes force, i.e. bouyancy, just use fix gravity. Of course, without additional time-scales from collisions or other modeled terms, i.e. drag laws, there will be no difference between the dynamics of your bouyancy corrected and purely gravity driven cases.
I am curious what you are modeling, that bouyancy is the main affector on the dynamics if you are not accounting for compressibility effects or interfaces. In most settling problems we are concerned with hydrodynamics not hydrostatics.
A per-atom variable, that you pass to fix addforce,
can reference a per-atom compute. The compute property/atom
command can reference any per-atom property (see its doc page),
including radius or diameter.
Steve
thank you all,