How to calculate the total forces acting on top and bottom walls with two meshes

Submitted by Huihui Weng on Wed, 02/19/2025 - 10:17

Hi all,

I define two gran/wall by two meshes:

# import the mesh for the top and bottom walls
fix bot_wall all mesh/surface/stress file wall_bot.stl type 1 stress on
fix top_wall all mesh/surface/stress file wall_top.stl type 1 stress on
fix zwalls all wall/gran model hertz tangential history mesh n_meshes 2 meshes top_wall bot_wall store_force_contact_stress yes

Then, I compute the force_normal, which includes both the top and bottom walls:

compute 1 all wall/gran/local force

Finally, I tried many ways to separate the different forces acting on the top and bottom walls, like to use compute reduce/region. But none of them work. Does someone know how to do that?

Best,
Huihui