[lammps-users] The parameters for z-cylinder wall

Dear all,

I’ve found many discussions about the subject in the mail list. However I have not enough confidence about my setting yet. Please just have a look about them. Thanks.

In fact the z-cylinder wall just describes a system that no period in xy-plane (round boundary) but z-axis. To the special case, several parameters will be related in the lammps:

dimension 3

boundary f f p

fix npt GB npt/asphere 0.8 0.8 0.1 aniso NULL NULL NULL NULL 2 2 20 dilate partial.

Whether we only need to just adjust the pressure for z ? And to realize such adjustment we need using “aniso” to and setting NULL to xy? Is there any fault in the setting above? Thanks in advance!

I suggest you try the commands you post questions about.
If the syntax is in error, LAMMPS will complain. If you
monitor the simulation, you will see if it does what you
expect. In this case, you would expect the x,y box dimensions
to stay constant and z to fluctuate. Using the proper
thermo_style custom options you can see if this happens.