Dear LAMMPS users,
I have a question about the fix add force, the documentation says that it adds force per atoms. If I want to calculate the total force added by this fix, should I multiply the force I used in the input file to the number of atoms in the group that fix is applied to?
Thank you for your help.
Dear LAMMPS users,
I have a question about the fix add force, the documentation says that it
adds force per atoms. If I want to calculate the total force added by this
fix, should I multiply the force I used in the input file to the number of
atoms in the group that fix is applied to?
yes and no. the total force is (obviously) the *sum* over all individual
forces. you can use a multiplication only, if you are adding the same force
to each atom in the group the fix is applied to, i.e. in case you use a
constant or an equal style variable, as then the sum over all individual
forces is that same as multiplying the individual force with the number of
particles in the group.
axel.