Help for pull atoms back in Lammps

Dear all,

   Recently, i simulate a case needing pull some atoms back to the domain. I tried boundary command of "f","s","m","p" , but they are not right. Because the domain lower boundary is fixed and upper boundary is open. Some atoms escape from upper bounday, and needed to pull back after each step. It seems the "shrink wrap" is not right. Thanks!

Bests,

Eric

Dear all,

Recently, i simulate a case needing pull some atoms back to the domain. I tried boundary command of "f","s","m","p" , but they are not right. Because the domain lower boundary is fixed and upper boundary is open. Some atoms escape from upper bounday, and needed to pull back after each step. It seems the "shrink wrap" is not right. Thanks!

no, it isn't.

to be more precise. this has nothing to do with boundary conditions.

axel.

As the boundary doc page states, shrink-wrap boundaries simply
fit the box to the atoms. They don't impose any extra force
on the atoms. You might look at the fix wall commands if
you want to constrain atom motion.

Steve