rotating container

Hi all

In the LIGGGHTS doc I've read about modeling a rotating container using the rotate keyword. I'd like to rotate a container with one particle inside. For more details I've adhered the in.rot file. My questions are:

1) Why do I need the lattice command for rotating?
2) What changes are necessary that the particle can move free and falling down under gravity?
3) Is it sufficient modeling the container just with the simulation box?
4) Why does the rotation not work with the rotate keyword in region? If I don't use the fix command (line 41) nothing will rotate. But when I use the fix, I don't need the rotate keyword in region anymore.
5) How can I visualize the region in paraview (not the bounding box, the true "rotating" region)?

Any help is welcome.
Claudio

Attachment	Size
in.rot_.txt	1.51 KB
in.rotorStator.txt	3.91 KB

Forums:

LIGGGHTS® - User Forum

msbentley | Thu, 10/20/2011 - 14:43

Hi Claudio, As far as I know,

Hi Claudio,

As far as I know, the rotate command is used to rotate groups of atoms without applying a realistic physical force. It does not represent a moving container. For this you could, for example, define your container as a mesh and use the fix move/mesh/gran to rotate it. You can also dump the position of the mesh over time (see the dump command) to visualise it in ParaView.

Alternatively you can use the standard wall command with the shear parameter to apply rotation (I think!).

Gravity isn't being applied to your particles because you haven't used a time integration fix, e.g. fix nve/sphere.

It is probably easiest to start with a simple simulation, e.g. add particles to a box and let them fall under gravity, and build the simulation from there.

Cheers, Mark

Claudio Wolfer | Thu, 10/20/2011 - 15:21

Hi Mark Thanks for help. I

Hi Mark

Thanks for help. I will create a mesh and build my case in the style of in.movingMeshGran (the only tutorial who uses the rotate keyword).

More hints are still welcome.
Claudio

raguelmoon | Thu, 10/27/2011 - 05:54

Hi user, You can rotate

Hi user,
You can rotate container with wall command and apply shear as Mark told. I used this technique to rotate cylindrical container. Also mesh can be rotated same way.

cheers, Ram

jooj | Mon, 01/02/2012 - 21:17

Can you attach input file for

Can you attach input file for rotating cylindrical container ?
Thx in advance !!

Claudio Wolfer | Tue, 01/10/2012 - 10:53

Attachment

Hi jooj

Above I attached an input file i used for a rotating geometry.
I hope it helps.

Claudio

Riccardo Maione | Tue, 01/21/2014 - 17:58

Hi Claudio

have you removed your file, because i can't see it anymore,

Riccardo