fix mesh/surface/stress/servo

Submitted by rasoul on Wed, 10/09/2013 - 08:10

For using "fix mesh/surface/stress/servo" I have to implement mesh (file filename.stl).
How can I do that?
I do not input mesh in my simulation.
Is there any other ways?

Thanks a lot in advance,

rasoul | Wed, 10/09/2013 - 22:50

I implement "fix xwalls1 all wall/gran/hertz/history primitive type 1 xplane ${XL}" in 6 direction for bounding my simulation domain and I use "mesh/surface/stress/servo" for adding stress (psi) to the one surface/edge of a simulation domain (box) which is poured by particles.
Mr. Kloss suggested me to use this command for doing that.

AGl | Thu, 10/10/2013 - 07:19

As far as I know "mesh/surface/stress/servo' can control mesh only.

ckloss's picture

ckloss | Thu, 10/10/2013 - 10:39

>>As far as I know "mesh/surface/stress/servo' can control mesh only.
Correct - but mesh walls can do anything that can be done with primitive walls


rasoul | Sun, 10/13/2013 - 12:07

How can I implement "mesh/surface/stress/servo" using primitive walls?
I say this because in the "mesh/surface/stress/servo" command, we have to use "File Filename.stl", but I do not have any .stl file in my simulation and I control the simulation domain by primitive walls.

I am looking forward to hearing from you.

PaulWinkler's picture

PaulWinkler | Mon, 11/04/2013 - 15:47


if you want to simulate a stress controlled compression, you have to replace your primitive walls by meshes. Build your mesh in gmsh or any other program. Only ASCII .stl files are supported (imho) yet. You can even edit them with an text editor, syntax is easy to learn. Load the mesh and use it as wall, now you can use mesh/surface/stress/servo in the proper way.
If you just want to move your primitive to do a simulation controlled by displacement, use fix move.



rasoul | Mon, 11/04/2013 - 20:55


I implemented mesh walls (stl file), but I faced an error. This is about unit system.
"ERROR: Mesh error: dimensions too small - use different unit system (multi_node_mesh_parallel_I.h536"

If anyone knows its reason, I am looking forward to know that.


rasoul | Tue, 11/05/2013 - 23:16


Yes, I am using SI and my meshes is 3D.

I am looking forward to hearing you.

Rasoul | Wed, 07/09/2014 - 16:24

Hi, there
How could it keep the pressure constant on the meshed wall as the lateral wall area increases during compression in the tri-axial compression test?
And another thing, how to implement it for a cylinder sample?

keeping moving forwards