rotate mesh with surface velocity

Submitted by Nils Borghoff on Mon, 11/06/2017 - 13:05

Hello everybody,

I want to simulate a belt conveyor which also rotates around a defined axis.
Normaly I used this command to give the surface of the belt velocity components

fix cv1 all mesh/surface/stress file belt_1.stl type 3 scale 0.001 surface_vel ${beltvX} ${beltvY} ${beltvZ}

Then I want ro rotate this mesh with following command

fix rotatecv1 all move/mesh mesh cv1 rotate origin 0.0 698.8 0.0 axis 0.0 0.0 1.0 period ${time1}

But this leads to an error: Illegal fix move/mesh command, cannot apply move to a mesh using keyword `velocity`or àngular_velocity`(../fix_move_mesh.cpp:91)

I am using LIGGGHTS-PUBLIC 3.5.0, compiled 2017-01-13
Is there any other method to combine these two actions? I hope of a lot of good solutions.

Best regards,
Nils

Westbrink | Mon, 11/06/2017 - 16:12

Hello Nils,

I discussed the same topic last time with some developers of LIGGGHTS. As far as I know, is this feature not possible.
You can try an iterative approach in a loop like:

fix surface_vel
unfix surface_vel
fix rotation
unfix rotation
...

Kind regards,
Fabian

Nils Borghoff | Tue, 11/07/2017 - 08:25

Hi Fabian,

thanks for your comment. We also think about this solution, but we hoped that there is a better one. I think, it is circumstantial to recalculate the new velocity components in X, Y and Z in each iterational step.
Best regards,
Nils

arnom's picture

arnom | Mon, 11/13/2017 - 17:24

Hi Nils,

this feature is not implemented at the moment as it would require some non-trivial modifications as you pointed out. If you require such a feature we could implement this for you as part of the LIGGGHTS premium version. If you are interested please contact my colleagues at office@dcs-computing.com for further details.

Best,
Arno

DCS team member & LIGGGHTS(R) core developer