Hi!
Maybe this should go to the LAMMPS mailing list but I'm using LIGGGHTS ... :) Mainly for information:
Is it a bug or intended behavior that there can be a linear motion when using fix move/mesh/gran rotate?
#Example:
atom_style granular
dimension 3
boundary m m m
newton off
communicate single vel yes
units si
region R_gesamt block -0.05 0.05 -0.05 0.05 -0.15 0.15 units box
create_box 1 R_gesamt
# Material properties
fix m1 all property/global youngsModulus peratomtype 2.63e5
fix m2 all property/global poissonsRatio peratomtype 0.27
fix m3 all property/global coefficientRestitution peratomtypepair 1 0.02
fix m4 all property/global coefficientFriction peratomtypepair 1 0.8
fix m6 all property/global cohesionEnergyDensity peratomtypepair 1 30.
pair_style gran/hertz/history 1 1
pair_coeff * *
timestep 0.00001
fix F_fl4 all mesh/gran plate.stl 1 0.001 -15.0 -15.0 70. 0. 0. 0.
fix F_fl all wall/gran/hertz/history 1 1 mesh/gran 1 F_fl4
dump D_stl all stl 800 geometrie01-*.stl
fix F_moveBox1 all move/mesh/gran rotate 0.015 0.015 0.070 0. 1. 0. 2. F_fl4 1
run 50000
fix F_moveBox1 all move/mesh/gran rotate 0.015 -0.015 0.070 0. 1. 0. 2. F_fl4 1
run 50000
fix F_moveBox1 all move/mesh/gran rotate 0.015 0.0 0.070 0. 1. 0. 2. F_fl4 1
run 50000
# ======
#plate.stl:
solid Mesh
facet normal 0.000000 0.000000 -1.000000
outer loop
vertex 0.000000 0.000000 0.000000
vertex 0.000000 30.000000 0.000000
vertex 30.000000 30.000000 0.000000
endloop
endfacet
facet normal 0.000000 0.000000 -1.000000
outer loop
vertex 30.000000 0.000000 0.000000
vertex 0.000000 0.000000 0.000000
vertex 30.000000 30.000000 0.000000
endloop
endfacet
endsolid Mesh
#=====
Regards,
Christian
ckloss | Thu, 05/06/2010 - 15:39
Re: fix move/mesh/gran rotate
Hi Christian,
>>Maybe this should go to the LAMMPS mailing list but I'm using LIGGGHTS ... :)
fix move/mesh/gran is not available in LAMMPS, it is specific to LIGGGHTS (as mentioned in the doc)
>>Mainly for information: Is it a bug or intended behavior that there can be a linear motion
>>when using fix move/mesh/gran rotate?
I am not sure if I understand the question right. The command is fix move/mesh/gran, and is has styles 'linear' ,'wiggle' and 'rotate', so one fix move/mesh/gran either rotates, wiggles or translates the mesh.
Christoph
cgrohs | Fri, 05/07/2010 - 10:11
Re:Re: fix move/mesh/gran rotate
Hi Christoph,
When you run my example you'll see a linear movement of the plate in y direction for the first and second "run" command although the fix move/mesh/gran rotate is used. The movement depends on the y coordinate of the origin point of axis of rotation. In the third "run" this value is 0.0 and therefore no linear movement of the plate occurs.
I thought that fix move/mesh/gran rotate leads to pure rotation, independent of the origin point of the axis of rotation.
Christian
ckloss | Fri, 05/07/2010 - 14:18
Re: Re:Re: fix move/mesh/gran rotate
Hi Christian,
you are right. This behavior is not intended. Thanks for reporting this. As soon as I have time, I'll have a look.
Christoph
ckloss | Fri, 05/14/2010 - 09:38
Re: Re:Re: fix move/mesh/gran rotate
Hi Christian,
the bug seems to be a LAMMPS bug. I will notify Steve and include the patch once available
Christoph
cgrohs | Fri, 05/14/2010 - 12:20
Re:
Hi Christoph,
that was why I said maybe it should go to the LAMMPS mailing list. But this way it's easier for me! :-) Thank you for putting so much effort into LIGGGHTS!
Christian
ckloss | Wed, 05/19/2010 - 18:05
Re:
There has been a LAMMPS patch that will be included in LIGGGHTS 1.0.2, downloadable today or tomorrow.
That should fix this issue.
regards,
Christoph