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Old   November 10, 2015, 10:23
Default mesh overlap
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saeed
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Hi,
I am trying Structure mesh and for some specific reason meshes overlap each other for instance 40% of domain 4 completely overlap dom 5 .
dom 4 BC`s is wall and dom 5 is Interface now my question is:
can fluent solve this kind of cases i mean what will happen if meshes overlap?
since i am using Extrude i cant split the domain because the block which is made by this command will be interrupted and i can`t reblock it
also I`m so willing for a suggestion for this problem to solve ?
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Old   November 11, 2015, 11:16
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David Garlisch
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I do not understand the description.

Please post some pictures or attach an example .pw file.

And please read this post.
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Old   November 13, 2015, 11:55
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Dear David:
here is the link of PW file and a picture.
http://www.filetolink.com/c16048dc30
I used Extrude Command(normal--->Adjacent grid) to make the Block 8 which includes Domain 4.
It`s Hard for me to use multiblock method to have St.Mesh threfore i`m trying the Extrude which looks more simple but the problem is:if I split Domain 4 the block8 will be deleted.
1-I wanted to know is there any way to prevent such problem or solve it?
2-If i Carry on with this method while Domain 4 and 5 are overlapped and they have various Bc`s (dom4=Wall & dom5=interface) can fluent handle such thing?
Best Regards
Attached Images
File Type: jpg Overlapping.jpg (106.5 KB, 10 views)

Last edited by mollaee.saeed; November 13, 2015 at 14:29.
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Old   November 16, 2015, 12:20
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David Garlisch
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I did not download the PW file you posted to filetolink. They wanted access to my facebook or google page to do the download. No thanks!

However, if I understand the image correctly, I think you will need to split the domains as you mentioned. Yes the extruded hex block will be deleted. However, if after splitting, the opposing IJK faces are balanced (a face can be 1 or more domains), you can use Create > Assemble Special > Block... to manually rebuild the structured block.

I have attached a simple collection of domains that can be assembled into a str block.

I hope this helps.
Attached Images
File Type: png AssembleSpecial.png (14.6 KB, 5 views)
Attached Files
File Type: zip AssembleSpecial.zip (18.9 KB, 4 views)

Last edited by dgarlisch; November 16, 2015 at 12:26. Reason: attachements
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Old   November 17, 2015, 01:31
Default PW File
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Unfortunately My opposing faces are not Balanced and it is hard to balance them or at least it is hard for me to do it and it was the main reason for using the Extrude but in extruding, in addition to the problem that was mentioned,there is some gaps that will appear after using extruding command which are completely confused me
I think it is important to say that the major problem for now is on top layer in the tip
Here is my PW file i Uploaded into Dropbox
https://www.dropbox.com/s/rzmkqbdwgj...cture.rar?dl=0

Best Regards
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Old   November 18, 2015, 11:58
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David Garlisch
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I was able to download the file without giving away all my personal info to an unknown-to-me website! Thanks!

I took a look at the file. You definitely have a complex topology. Since you want a structured grid, this is probably beyond my ability to answer.

However, as I assume you already know, you must have everything balanced to build structured blocks. You probably need to spend some time figuring out the high level block topology needed to handle this design. Then, you will know which tools to use to create the blocks. For more complex blocks, you will most likely be building some domains "by hand" and assembling the blocks accordingly.

Anyone else willing to tackle this?
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Old   November 23, 2015, 04:48
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Dear David:
Thanks a lot for the time that you spend on this problem.
best Regards
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Old   December 1, 2015, 13:15
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Hi Mollaee,

I took a look at the Pointwise project file you shared (i.e. 6.pw). I noticed that you created a few blocks, and then you added connectors that overlapped the connectors already being used by existing blocks. Typically, you want to avoid this and instead have adjacent domains share a single edge (which may be composed of multiple connectors), and likewise blocks should share a single face (which may, or may not be composed of multiple domains). Doing so ensures that the interface between each block is point matched. There are some rare occasions where using non-matching interfaces is a valid approach, but you have to ensure your solver supports this capability. However, doing so is usually a last resort for a very complicated model. Your case is simple enough, where you should be able to avoid this entirely.

I've gone ahead and created a block in the region where you were originally having overlap using an extrusion. You can download the Pointwise project file using this link. Here the block is point matched with the existing domains which you created. Notice, however that the inner blocks that you have created are not point matched, because you have used multiple overlapping domains to create your blocks. You will likely want to revisit this and ensure the interfaces between adjacent blocks share the same set of domains. I hope this helps.

Best Regards,


Zach

Last edited by RcktMan77; December 17, 2015 at 13:38.
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