fix mesh/gran

Hello again!

I got an unexpected behavior with the "fix mesh/gran":
Originally I wanted to rotate a plane around the z-axis but nothing happend (F_fl0 in the example). Then I tried to rotate the plane around the y-axis (F_fl2 to F_fl6) but there is an additional (unexpected) rotation around the z-axis ... not what I wanted ...
Workaround would be to change the .stl-file ...
Regards,
Christian

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# Example:
atom_style granular
dimension 3
boundary m m m
newton off
communicate single vel yes
units si
region R_gesamt block -0.5 0.5 -0.5 0.5 -0.5 0.5 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_gravi all gravity 9.81 vector 0.0 0.0 -1.0
lattice sc 1.0
create_atoms 1 single 0 0 0
fix F_fl0 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 0.0 45.0
fix F_fl1 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 0.0 0.0
fix F_fl2 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 5.0 0.0
fix F_fl3 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 10.0 0.0
fix F_fl4 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 20.0 0.0
fix F_fl5 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 40.0 0.0
fix F_fl6 all mesh/gran winkel1.stl 1 0.001 0.0 0.0 0.0 0.0 80.0 0.0
run 1
dump D_stl all stl 1 geometrie02-*.stl
run 2 upto
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File winkel1.stl:
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solid Mesh
facet normal 1.000000 0.000000 -0.000000
outer loop
vertex -0.000000 70.000000 -0.000000
vertex 0.000000 70.000000 100.000000
vertex 0.000000 0.000000 100.000000
endloop
endfacet
facet normal 1.000000 0.000000 -0.000000
outer loop
vertex -0.000000 70.000000 -0.000000
vertex 0.000000 0.000000 100.000000
vertex -0.000000 0.000000 -0.000000
endloop
endfacet
endsolid Mesh
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