Simulations combining small oscillations and simple shear

LAMMPS LAMMPS General Discussion
1

Hello.
I am using LAMMPS version lammps-22Dec2022 on the CentOS operating system. I would like to apply sinusoidal small oscillations and simple shear simultaneously to the system, with oscillations in the yz plane and shear in the xy plane as shown in the figure below.
combine_shear_oscillation
To achieve this, the oscillations and shear should deform the box, followed by updating particle positions and velocities using the NVT thermostat. The core commands I have considered are as follows:

fix           shear_deform all deform 1 xy erate ${shear_rate} remap v
fix           wiggle_deform all deform 1 yz wiggle $(v_A) $(v_T) remap v units box
compute       unbiased_temp all temp/profile 1 0 1 y $(v_ybins) out bin
fix           move all nvt temp 1.0 1.0 $(100*dt)
fix_modify    move temp unbiased_temp

It appears that LAMMPS does not allow applying two types of deform simultaneously to the box. Therefore, if there is a way to achieve similar functionality in LAMMPS, I would greatly appreciate any guidance.

Thank you in advance.

2

The reason for LAMMPS to refuse such a combination is that those two deformations are not independent since you have requested two shearing deformations that share one dimension (well, it is obviously not possible in a 3d system to have two independent shearing deformations).

3

Is this what you want?

fix           shear_deform all deform 1 xy erate ${shear_rate}  yz wiggle $(v_A) $(v_T) remap v units box
4

Thanks for your reply, I’ll try the commands you showed.