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how to use quad mesh in comsol 4
Posted Jun 16, 2010, 10:37 p.m. EDT 7 Replies
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Hi
Actually I couldn’t use the free quad mesh and also I don’t know how to quad mesh my geometry,
I tried to use swept method but I encounter with some errors.
I would appreciate you if you let me know how to mesh it.
I tried to attached my simulation to this message but the error #2028 was appeared in my screen.
Actually I couldn’t use the free quad mesh and also I don’t know how to quad mesh my geometry,
I tried to use swept method but I encounter with some errors.
I would appreciate you if you let me know how to mesh it.
I tried to attached my simulation to this message but the error #2028 was appeared in my screen.
7 Replies Last Post Jun 25, 2010, 3:20 a.m. EDT
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Posted:
1 decade ago
Hi
if you are still in 3.5, know that there are less limitations in V4 it's easier (also because the volume are represented differently, again this depends if you are in extrenal CAD mode or COMSOL graphics mode) but the principles remain. I agree it took me some time too to catch the essentials.
My best homework exercice was/is to make a simple rectangle (start in 2D then extrude in 3D and continue, note that in 2D a quad or a tet are equivalent on an edge, it differs on the surfaces) and mesh that one, by first selecting an edge/ surface then use the sweep function for the surfaces (sory swwep is only in 3D), first automatic then by hand, same for quads, try also out by hand meshing one or two edges first
Then you split one of the edges by adding a point somewhere (a line cutting the face in 3D but enforce the split with the geoemetry commands so it appears in the "analysed geoemtry") i.e. in the middle of an edge, the geometry has not changed, but the number of faces has, try it out again same procedure but starting sequentially in the 4 directions.
You will notice that the sweep function has some limitations, and requires that the mesh on the start and arrival paralle faces are identical (use the copy mesh function) and you can go from N faces to 1 (or the opposite I always forget ;) but not the other way.
Then you can try out the quads/mapped on a L shaped surface (2D) made as a) one surface no interiour boundaries b) two adjacent rectangles
Once you have uderstood these functionalities, you should be well tooled to mesh a full complex CAD model (start with fine mesh on delicate and critical items, then move outwards with coarser mesh
Have fun Comsoling
Ivar
if you are still in 3.5, know that there are less limitations in V4 it's easier (also because the volume are represented differently, again this depends if you are in extrenal CAD mode or COMSOL graphics mode) but the principles remain. I agree it took me some time too to catch the essentials.
My best homework exercice was/is to make a simple rectangle (start in 2D then extrude in 3D and continue, note that in 2D a quad or a tet are equivalent on an edge, it differs on the surfaces) and mesh that one, by first selecting an edge/ surface then use the sweep function for the surfaces (sory swwep is only in 3D), first automatic then by hand, same for quads, try also out by hand meshing one or two edges first
Then you split one of the edges by adding a point somewhere (a line cutting the face in 3D but enforce the split with the geoemetry commands so it appears in the "analysed geoemtry") i.e. in the middle of an edge, the geometry has not changed, but the number of faces has, try it out again same procedure but starting sequentially in the 4 directions.
You will notice that the sweep function has some limitations, and requires that the mesh on the start and arrival paralle faces are identical (use the copy mesh function) and you can go from N faces to 1 (or the opposite I always forget ;) but not the other way.
Then you can try out the quads/mapped on a L shaped surface (2D) made as a) one surface no interiour boundaries b) two adjacent rectangles
Once you have uderstood these functionalities, you should be well tooled to mesh a full complex CAD model (start with fine mesh on delicate and critical items, then move outwards with coarser mesh
Have fun Comsoling
Ivar
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Posted:
1 decade ago
Hi again
here is an example of 3.5 that you an normally import into 4 too, but you can make better items easily
Ivar
here is an example of 3.5 that you an normally import into 4 too, but you can make better items easily
Ivar
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Posted:
1 decade ago
thanks for quick respond
I tried whatever you told me,but unfortunately it didn't work.
is there any way to import *.inp in comsol 3.5 a or 4?
the abacouse software is the only software the meshed my geometry as quad(hex).
i want to know how could i used the meshed file(*.inp) in comsol .
or how could i used txt file of inp and replace nodes and *Element, type=C3D8R into my geometry ?
I really need the quad mesh .
I tried whatever you told me,but unfortunately it didn't work.
is there any way to import *.inp in comsol 3.5 a or 4?
the abacouse software is the only software the meshed my geometry as quad(hex).
i want to know how could i used the meshed file(*.inp) in comsol .
or how could i used txt file of inp and replace nodes and *Element, type=C3D8R into my geometry ?
I really need the quad mesh .
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Posted:
1 decade ago
Hi
Well from my experience its only NASTRAN neutral files that can be imported as mesh structures in COMSOL, so try to get your model translater further to this format.
But there should be ways to model your case too in COMSOL, probably you need to "cut" it up with more internal boundaries.
Meshing is rather an art than a science though
Good luck
Ivar
Well from my experience its only NASTRAN neutral files that can be imported as mesh structures in COMSOL, so try to get your model translater further to this format.
But there should be ways to model your case too in COMSOL, probably you need to "cut" it up with more internal boundaries.
Meshing is rather an art than a science though
Good luck
Ivar
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Posted:
1 decade ago
thank you for your respond,
I tried the patran and the nastran.
in addition,I have another question , let me to explain in this way:
2 modules are used in my model
1-Fluid flow(Laminar Flow)
2-Transport of dilute species
How could I Solve my model first with the module 1 and then use the result and solve the model via the module 2?
I mean first solved my laminar flow model and then solve the mass transfer model.
I read the help But I don't know how to solve the sequence solver in the comsol 4.
I tried the patran and the nastran.
in addition,I have another question , let me to explain in this way:
2 modules are used in my model
1-Fluid flow(Laminar Flow)
2-Transport of dilute species
How could I Solve my model first with the module 1 and then use the result and solve the model via the module 2?
I mean first solved my laminar flow model and then solve the mass transfer model.
I read the help But I don't know how to solve the sequence solver in the comsol 4.
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
thank you for your respond,
I tried the patran and the nastran.
in addition,I have another question , let me to explain in this way:
2 modules are used in my model
1-Fluid flow(Laminar Flow)
2-Transport of dilute species
How could I Solve my model first with the module 1 and then use the result and solve the model via the module 2?
I mean first solved my laminar flow model and then solve the mass transfer model.
I read the help But I don't know how to solve the sequence solver in the comsol 4.
I tried the patran and the nastran.
in addition,I have another question , let me to explain in this way:
2 modules are used in my model
1-Fluid flow(Laminar Flow)
2-Transport of dilute species
How could I Solve my model first with the module 1 and then use the result and solve the model via the module 2?
I mean first solved my laminar flow model and then solve the mass transfer model.
I read the help But I don't know how to solve the sequence solver in the comsol 4.
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
check the forum, other have asked and solved this in V4. Basically you have two ways, either COMSOl understands the issue in its defualt "automatic " way and generates the good sequences, either you must edit and mke them yourself (i.e. starting from the one generated by COMSOL, but in4.0 you cannot easily insert something in the middle of a sequence, I have heard this will be possible soon :) and last you can override the "automatic settings for the physics and choose there the sequence to be the sole master on board, check the Advanced sub tab of the main physics node entry
have fun Comsoling
Ivar
check the forum, other have asked and solved this in V4. Basically you have two ways, either COMSOl understands the issue in its defualt "automatic " way and generates the good sequences, either you must edit and mke them yourself (i.e. starting from the one generated by COMSOL, but in4.0 you cannot easily insert something in the middle of a sequence, I have heard this will be possible soon :) and last you can override the "automatic settings for the physics and choose there the sequence to be the sole master on board, check the Advanced sub tab of the main physics node entry
have fun Comsoling
Ivar