[lammps-users] About setforce command

Dear all,

For one simulation body, I set its properties via fix as follows:
fix 1 body rigid single
fix 2 body setforce 0 0 0

Then I set the body’s velocity via command: velocity body set 2 0 0. I dump the body’s velocity during simulation, and I found that the x-velocity is indeed 2, however, the y- and z-velocity is not zero. Why this happened? Will anyone tell me how to make the y- and z-velocity keep zero during the simulation? Thanks


Don't make it a rigid body. The fix rigid command
does its own time integration. Just set the force
to zero on the atoms and set their initial velocities.


2008/3/16 jjzh505 <[email protected]>: