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[ICEM] Meshing problem in Formula one

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Old   January 13, 2013, 12:43
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i'll check that link in my lab , in canada you are limited by data from you internet provider. you have a limit of 30Gb. you pay for additional mb you download what it is ? tutorial ? about the define cut, you will need it for the volume meshing process...
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Old   January 13, 2013, 12:46
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My limit is 15 GB .

Downside of Tgrid is that, it is only volume mesher and no additional tools are there. Need surface mesh.

Tyre is closed surface and road is also part of closed outer boundary. So no need to define thin cuts ...
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Old   January 13, 2013, 12:49
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My limit is 15 GB
i tought unlimited internet is everywhere but canada....

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Tyre is closed surface and road is also part of closed outer boundary.
I'm not sure i understand what you mean by that
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Old   January 13, 2013, 12:51
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Quote:
Originally Posted by diamondx View Post
I'm not sure i understand what you mean by that
1. It is not a sharp interface.

2. Moreover it is required for octree method, not for the method I am following i.e. surface mesh + denauly volume meshing

3. It is not inside the volume but rather a boundary.

PS. This is my rough experience with ICEM tetra, so pls apply this info on your own risk.....
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Old   January 14, 2013, 05:38
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I am working step by step and therefore progress is very slow.

These are my observations :

1. Good geometry is important

2. I need to set the many local parameters along with the curve parameters.

I have one query here:

The common curve between two surfaces should be part of which surface ? Surface 1 or 2? or Both (how is that possible?) ? If I dont build the topology then I have to create the one curve for each surface! In this case how to define the curve parameters?







You have meshed all surfaces with Patch dependent method or have skipped some surfaces to allow octree algorithm to mesh those with patch independent?
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Old   January 14, 2013, 05:43
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All surfaces with patch dependent. Just working like gamibt . But it is cumbersome job.
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Old   January 14, 2013, 06:07
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I need to set the many local parameters along with the curve parameters.
Only surface mesh parameters are not working? which local parameters and curve parameters other than no. of nodes?

What's the difference you have found between Patch Independent and Patch Dependent?
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Old   January 14, 2013, 06:34
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Originally Posted by cfd seeker View Post
Only surface mesh parameters are not working? which local parameters and curve parameters other than no. of nodes?
Every thing is working now. There are many parameters such as global mesh parameters (I dont know whether they have something to do with surface mesh), surface mesh parameters, Part mesh parameters etc

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What's the difference you have found between Patch Independent and Patch Dependent?
I am not using PI in surface mesh mode, as I am not able to understand its working.
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Old   January 14, 2013, 06:42
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There are many parameters such as global mesh parameters (I dont know whether they have something to do with surface mesh), surface mesh parameters, Part mesh parameters etc
I am asking this because part mesh parameters overrides global parameters, surface mesh parameters overrides part parameters and curve parameters overrides surface parameters....but if you skip something for curve parameters it will take that from surface, parts or global which ever is set before curve parameters. So if you had to go down to curve parameters to properly capture the geometry then you can directly set "Global Parameters" and then set "Curve parameters"
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Old   January 14, 2013, 06:51
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Quote:
Originally Posted by cfd seeker View Post
I am asking this because part mesh parameters overrides global parameters, surface mesh parameters overrides part parameters and curve parameters overrides surface parameters....but if you skip something for curve parameters it will take that from surface, parts or global which ever is set before curve parameters. So if you had to go down to curve parameters to properly capture the geometry then you can directly set "Global Parameters" and then set "Curve parameters"
Not really. Surfaces mesh parameters are used for the interior of surface. Curve mesh parameters are used for the boundary. Shell mesh parameters serves as the direction provider (means how ICEM should work) + limiter.

It is somehow complicated setting...
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Old   January 14, 2013, 08:04
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a) Patch dependent
This is working now. But always get the problem in innder region while the mesh at the boundary is fixed through curve mesh parameters. I am also using the following options:

i) respect line elements (is this necessary?)

ii) protect boundary elements

iii) project to surface

iv) adpat mesh interior (affected by surface mesh parameters and succesfully used it in this model. Got idea from the one of the Simon's post)

v) Try harder 1 and some times 3. But dont see any effect in current method
What are these parameters? Can you explain their effect on the final mesh? they effect octree or delaunay?
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Old   January 14, 2013, 08:33
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Quote:
Originally Posted by cfd seeker View Post
What are these parameters? Can you explain their effect on the final mesh? they effect octree or delaunay?

i) respect line elements (is this necessary?)
This is to force algorithm that it follows the curve parameters religiously. But I think it is more important in PI, as patch dependent always use the curve info

ii) protect boundary elements
Same as above. But it has something to do with element instead of line elements

iii) project to surface
Project the mesh to surface. Some times there is high curvature and no of elements are low. This option tries to match the coarse mesh with surface definition.

iv) adpat mesh interior (affected by surface mesh parameters and successfully used it in this model. Got idea from the one of the Simon's post)
Yes this is the main trick. It uses the surface mesh parameters to mesh the interior of geometry. Because Patch dependent method always uses the curve info but not the surface mesh parameters in default mode. So turning on this option will forces the surfaces mesh parameters to work with curve mesh parameters. It is profound effect on the overall surface mesh.

v) Try harder 1 and some times 3. But dont see any effect in current method
I dont see any effect in my case. But you remember the wind body tutorials where it is used to mesh the highly curved nose geometry by setting it to 3

I have tried to answer all questions in simplest way, but I am still in learning mode so if you have some input please do share.
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Old   January 14, 2013, 09:40
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Thanks far thanks a lot for taking out time to share all the info. I thiank we can learnmore by sharing info

Quote:
iv) adpat mesh interior (affected by surface mesh parameters and successfully used it in this model. Got idea from the one of the Simon's post)
Yes this is the main trick. It uses the surface mesh parameters to mesh the interior of geometry. Because Patch dependent method always uses the curve info but not the surface mesh parameters in default mode. So turning on this option will forces the surfaces mesh parameters to work with curve mesh parameters. It is profound effect on the overall surface mesh.
Can you please post few pics which show the effect of this parameter......
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Old   January 14, 2013, 10:19
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You have meshed all surfaces with Patch dependent method or have skipped some surfaces to allow octree algorithm to mesh those with patch independent?
He has to mesh all the surfaces... he cannot skipe some. because later he will have to apply delaunay... octree mesh will not work or it will change his actual surface mesh.
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Old   January 14, 2013, 10:26
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Downside of Tgrid is that, it is only volume mesher and no additional tools are there. Need surface mesh.
Not quite true. TGrid can re-triangulate surface meshes using sizing functions etc (and by surface meshes we mean Faceted geometry - and you can easily convert NURBS into fitted faceted surfaces even in ICEM). However, v14.5 TGrid (now called Fluent Meshing) also supports geometry import and surface meshing from geometry (like STEP files etc), and then making a volume mesh from the generated surface mesh.

If you weren't such a girl and reared your ugly head on GTalk/Skype here and there, I could've helped you with this already.

xoxo turbofar
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Old   January 14, 2013, 10:29
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Not quite true. TGrid can re-triangulate surface meshes using sizing functions etc (and by surface meshes we mean Faceted geometry - and you can easily convert NURBS into fitted faceted surfaces even in ICEM). However, v14.5 TGrid (now called Fluent Meshing) also supports geometry import and surface meshing from geometry (like STEP files etc), and then making a volume mesh from the generated surface mesh.
True. But not as strong as the true mesher like ICEM, Gambit, Gridgen... are ...

Tgrid is now called Fluent meshing? standalone or in workbench?


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If you weren't such a girl and reared your ugly head on GTalk/Skype here and there, I could've helped you with this already.

xoxo turbofar
ROFL
Hey I tried to connect with you. But you are not being shown in my Gtalk. do you know how to do this?
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Old   January 14, 2013, 10:32
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I could've helped you with this already.

xoxo turbofar
Hey you know, I enjoy learning and meshing
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Old   January 14, 2013, 10:36
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Quote:
Originally Posted by Far View Post
True. But not as strong as the true mesher like ICEM, Gambit, Gridgen... are ...
In fact, you might be surprised. All the sizing functions (proximity, curvature, min angle, element size, body of influence hard/soft) that are implemented in ANSYS Meshing (workbench meshing module) are from TGrid. There are also tools for manual repair of holes etc, if you combined some of these with the new/improved wrapping algorithm.. Magic can happen.

Quote:
Originally Posted by Far View Post
Tgrid is now called Fluent meshing? standalone or in workbench?
It's available both in Workbench and as standalone, you just start Fluent and there's an option to switch to meshing mode.

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Hey I tried to connect with you. But you are not being shown in my Gtalk. do you know how to do this?
FILTHY LIES! You are shown as offline on my GTalk, and everyone else is online and dandy. Fix it. I miss the good old times when you whispered sweet nothings to me in late night hours. Hu ha.
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Old   January 14, 2013, 10:41
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Originally Posted by scipy View Post
In fact, you might be surprised. All the sizing functions (proximity, curvature, min angle, element size, body of influence hard/soft) that are implemented in ANSYS Meshing (workbench meshing module) are from TGrid. There are also tools for manual repair of holes etc, if you combined some of these with the new/improved wrapping algorithm.. Magic can happen.
Hey I know this. I am talking about the difference between true mesher and the Tgrid. I know Tgrid algorithms are in Ansys meshing and ICEM.

Body of influence is know as wake region I think in Tgrid. Right ?

Yeah I saw these manual repair tools and are awesome. Like adding the missing face...
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Old   January 14, 2013, 10:45
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I miss the good old times when you whispered sweet nothings to me in late night hours. Hu ha.
Hey I thought you are girl. Thats why I talked to you in late hours. And those sweet nothings were due to fact that somebody was home

But I wasted my time, as you are in crotia and turned to be boy instead hehehe\



Ok. Any serious input to the topic ?
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