rotate the wall

Submitted by shokeyi on Tue, 08/13/2013 - 23:06

Hi everyone,
I tried to give the wall an angle velocity with "fix move/mesh" command. It gives as "fix c1 all move/mesh mesh cad1 rotate/variable origin 0 0 0 axis 1 1 1 omega 0.5". However, the result shows "ERROR: Variable name 1 for fix move/mesh rotate dynamic does not exist (mesh_mover.cpp:329)". Does anyone know how to modify it? My LIGGGHTS version is 2.2. Thanks.

richti83's picture

richti83 | Wed, 08/14/2013 - 09:40

Hi
for the move rotate/variable style you need a variable as input for omega. For example
variable w equal 2*PI*n
fix c1 all move/mesh mesh cad1 rotate/variable origin 0 0 0 axis 1 1 1 omega v_w

the v_ indicates for the parser that a variable name will follow and w is the name of the variable.
The advantage is, that you can manipulate the rotational speed (for example by setting variable n equal step*0.1 for an accelerated motion)
If you want to have an static motion use fix move rotate instead and set
variable T equal 1/$w
fix c1 all move/mesh mesh cad1 rotate/variable origin 0 0 0 axis 1 1 1 period $T
It will be faster because $T is only evaluated once (while v_w is evalutated every iteration step)
Take care of the difference between ${variable-name} and v_VARIABLENAME.

Best,
Christian

I'm not an associate of DCS GmbH and not a core developer of LIGGGHTS®
but I have 7 years user experience using LIGGGHTS®, ParaView and LINUX