Problem in meshing

sophie-l · April 12, 2009, 16:20

hello everybody,
i have 2 cylinders: the first is the big one and it isvertical and the other is small and tangent to the first.
i splited the 2 volumes, than meshed the big one with hexa. When i am trying to mesh the small one (with tetra) a message appears:
check the skewness of your face meshes and make suree the mesh face sizes are not too large in areas of small gaps.
what should i do?
thanks for ure help

sophie-l · April 13, 2009, 12:10

someone told me that i must do non conform meshing....what is this?

-mAx- · April 14, 2009, 02:59

Your mesh with tetra-hexcore at the junction.
you may have hexa mesh at the biggest junction, but not at the smallest because of the tangential edges ( I assume)
********
volume create height 1.7145 radius1 0.04445 radius3 0.04445 offset 0 0 \
0.85725 zaxis frustum
volume create height 0.1 radius1 0.015875 radius3 0.015875 offset 0 0 0.05 \
zaxis frustum
volume move "volume.2" dangle -63 vector 0 1 0 origin 0 0 0
volume move "volume.2" offset 0 0 1.5621
volume move "volume.2" offset 0 0.028575 0
volume create height 0.3 radius1 0.0381 radius3 0.0381 offset 0 0 0.15 zaxis frustum
volume move "volume.3" dangle -90 vector 1 0 0 origin 0 0 0
volume move "volume.3" offset 0 0 0.1016
default set "GRAPHICS.GENERAL.CONNECTIVITY_BASED_COLORING" numeric 1
default set "GRAPHICS.GENERAL.CONNECTIVITY_BASED_COLORING" numeric 0
volume unite volumes "volume.1" "volume.3"
volume unite volumes "volume.1" "volume.2"
vertex summarize "vertex.7"
face cmove "face.1" multiple 1 offset 0 0 0.5
face move "face.11" offset 0 0 -0.2
face move "face.11" offset 0 0 -0.1
volume split "volume.1" faces "face.11" connected
face cmove "face.3" multiple 1 offset 0 0 -0.1
face move "face.13" offset 0 0 -0.1
volume split "volume.1" faces "face.13" connected
face cmove "face.9" multiple 1 offset 0 -0.2 0
volume split "volume.2" faces "face.15" connected
undo begingroup
blayer create first 0.001 growth 1.2 total 0.005368 rows 4 transition 1 trows \
0 uniform
blayer attach "b_layer.1" volume "volume.2" "volume.2" "volume.4" "volume.1" \
"volume.3" "volume.3" face "face.2" "face.16" "face.10" "face.14" "face.12" \
"face.5" add
undo endgroup
face mesh "face.15" pave size 0.01
volume mesh "volume.4" cooper source "face.15" "face.9" size 0.01
face mesh "face.11" pave size 0.01
volume mesh "volume.1" cooper source "face.11" "face.13" size 0.01
sfunction create sourcefaces "face.5" startsize 0.005 growthrate 1.2 \
sizelimit 0.01 attachvolumes "volume.3" fixed
sfunction bgrid attachvolumes "volume.3"
volume mesh "volume.3" hexcore native offsetlayers 3 quadsplit hangingnodes \
size 1
volume mesh "volume.2" hexcore native offsetlayers 3 quadsplit hangingnodes \
size 0.01

April 12, 2009, 16:20	Problem in meshing	#1
sophie-l New Member sophie Join Date: Apr 2009 Posts: 8 Rep Power: 17	hello everybody, i have 2 cylinders: the first is the big one and it isvertical and the other is small and tangent to the first. i splited the 2 volumes, than meshed the big one with hexa. When i am trying to mesh the small one (with tetra) a message appears: check the skewness of your face meshes and make suree the mesh face sizes are not too large in areas of small gaps. what should i do? thanks for ure help

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April 13, 2009, 12:10		#2
sophie-l New Member sophie Join Date: Apr 2009 Posts: 8 Rep Power: 17	someone told me that i must do non conform meshing....what is this?

April 14, 2009, 02:59		#3
-mAx- Super Moderator Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,297 Rep Power: 41	Your mesh with tetra-hexcore at the junction. you may have hexa mesh at the biggest junction, but not at the smallest because of the tangential edges ( I assume) ******** volume create height 1.7145 radius1 0.04445 radius3 0.04445 offset 0 0 \ 0.85725 zaxis frustum volume create height 0.1 radius1 0.015875 radius3 0.015875 offset 0 0 0.05 \ zaxis frustum volume move "volume.2" dangle -63 vector 0 1 0 origin 0 0 0 volume move "volume.2" offset 0 0 1.5621 volume move "volume.2" offset 0 0.028575 0 volume create height 0.3 radius1 0.0381 radius3 0.0381 offset 0 0 0.15 zaxis frustum volume move "volume.3" dangle -90 vector 1 0 0 origin 0 0 0 volume move "volume.3" offset 0 0 0.1016 default set "GRAPHICS.GENERAL.CONNECTIVITY_BASED_COLORING" numeric 1 default set "GRAPHICS.GENERAL.CONNECTIVITY_BASED_COLORING" numeric 0 volume unite volumes "volume.1" "volume.3" volume unite volumes "volume.1" "volume.2" vertex summarize "vertex.7" face cmove "face.1" multiple 1 offset 0 0 0.5 face move "face.11" offset 0 0 -0.2 face move "face.11" offset 0 0 -0.1 volume split "volume.1" faces "face.11" connected face cmove "face.3" multiple 1 offset 0 0 -0.1 face move "face.13" offset 0 0 -0.1 volume split "volume.1" faces "face.13" connected face cmove "face.9" multiple 1 offset 0 -0.2 0 volume split "volume.2" faces "face.15" connected undo begingroup blayer create first 0.001 growth 1.2 total 0.005368 rows 4 transition 1 trows \ 0 uniform blayer attach "b_layer.1" volume "volume.2" "volume.2" "volume.4" "volume.1" \ "volume.3" "volume.3" face "face.2" "face.16" "face.10" "face.14" "face.12" \ "face.5" add undo endgroup face mesh "face.15" pave size 0.01 volume mesh "volume.4" cooper source "face.15" "face.9" size 0.01 face mesh "face.11" pave size 0.01 volume mesh "volume.1" cooper source "face.11" "face.13" size 0.01 sfunction create sourcefaces "face.5" startsize 0.005 growthrate 1.2 \ sizelimit 0.01 attachvolumes "volume.3" fixed sfunction bgrid attachvolumes "volume.3" volume mesh "volume.3" hexcore native offsetlayers 3 quadsplit hangingnodes \ size 1 volume mesh "volume.2" hexcore native offsetlayers 3 quadsplit hangingnodes \ size 0.01