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strange problem with structured mesh

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Old   March 5, 2014, 17:55
Post strange problem with structured mesh
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Fangping
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I am a novice in pointwise. I just want to try a structured mesh for a 10*10 rectangle. First I just set the dimension as 81 for each connector and made the structure domain, see figure.1 below. However when I increased the dimension to a higher number such as 91, it didn't work, why? see figure.2.
It is very strange and frustrated. Any help is appreciated.
1.jpg

2.jpg
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Old   March 6, 2014, 00:41
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I suggest you to split the connector to half on all four sides and mesh for the four partitions.
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Old   March 6, 2014, 09:45
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That is strange. It should not be necessary to split the connectors for such a trivial grid.

I created such a domain but didn't see this problem. Can you attach the grid for me to look at? While you can't upload .pw files, if you change the extension to .zip, you can attach it.
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Old   March 6, 2014, 09:59
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Quote:
Originally Posted by cnsidero View Post
That is strange. It should not be necessary to split the connectors for such a trivial grid.

I created such a domain but didn't see this problem. Can you attach the grid for me to look at? While you can't upload .pw files, if you change the extension to .zip, you can attach it.
Thank you so much, Chris. Please see the attach.
Attachment 29159
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Old   March 6, 2014, 11:55
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The forum didn't link the attachment. Send me a PM and you can arrange to email it to me.
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Old   March 6, 2014, 15:23
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Fangping

I loaded your .pw file into Pointwise and it looks OK (see image). Which version of Pointwise are you using?
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File Type: jpg rectangle-OK.jpg (33.5 KB, 29 views)
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Old   March 6, 2014, 15:28
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Quote:
Originally Posted by cnsidero View Post
Fangping

I loaded your .pw file into Pointwise and it looks OK (see image). Which version of Pointwise are you using?
It is V17.1R4.
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Old   March 6, 2014, 15:49
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That's the version I tested it with (see previous image).

Are you still experiencing this problem? My only suggestion at this point is to select the domain and reinitialize it (button with little blue square with yellow star on the corner).
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Old   March 6, 2014, 15:51
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Similarly for a very simple extrusion problem. If I set the dimension number less than 90 and extrudes it for 10 steps, it works (figure.1). However once I increases the dimension number over 90, it doesn't work neither (figure.2).
1.jpg

2.jpg
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Old   March 7, 2014, 09:12
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That's very weird behavior. Do you see the same behavior if you use more than 91 points?
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Old   March 7, 2014, 09:55
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Quote:
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That's very weird behavior. Do you see the same behavior if you use more than 91 points?
Yes, as long as I use more than 85 points it doesn't work.
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Old   March 7, 2014, 10:39
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Can you report to me the model and tolerance values from File>Properties.

If it's not that, I'm leaning towards this being some obscure platform related bug. Which OS are you running? 32 or 64bit?
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Old   March 7, 2014, 10:53
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Quote:
Originally Posted by cnsidero View Post
Can you report to me the model and tolerance values from File>Properties.

If it's not that, I'm leaning towards this being some obscure platform related bug. Which OS are you running? 32 or 64bit?
model size: 1000.0
node: 0.0001
connector: 0.0001
grid point: 1.0e-7

my OS is 64-bit.
Thanks!
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Old   March 7, 2014, 10:57
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I did have one other thought. Can you change the display precision to double (Edit>Preferences, Graphics) and see if you get the same result. I might be a rendering issue.

If that's not it, I'm out of ideas :-/
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Old   March 7, 2014, 11:56
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Quote:
Originally Posted by cnsidero View Post
I did have one other thought. Can you change the display precision to double (Edit>Preferences, Graphics) and see if you get the same result. I might be a rendering issue.

If that's not it, I'm out of ideas :-/
Oh, it works, thank you so much, Chris! you helped me a lot.
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Old   March 7, 2014, 12:41
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Phew. Now that I know I am also able to replicate the issue. I'm surprised it was that sensitive.

Perhaps Pointwise can educate us on why that it does this. Strange when the range of floating point values only vary a couple of orders of magnitude. Perhaps you should submit a bug report and have them look at it.

Last edited by cnsidero; March 7, 2014 at 14:27.
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