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[ICEM] Operation "Mirror Blocks" defect

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Old   March 22, 2012, 14:16
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4) taking another look at that squished disk, I think I see both an Ogrid and an HGrid overlapping... Perhaps you tried to put an Ogrid only within that pipe? You should run that OGrid thru the entire model instead...

If I get a chance, I will come back and show you later.

Simon
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Old   March 22, 2012, 16:08
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@Far: forget about question no. 2 - obviously I had forgotten the Elbow-Tutorial...argh; thx for the reminder.

@PSYMN:
"3) At the interface between the pipes, is there a surface? If it is open flow, there shouldn't be and the blocking should be continuous without trying to project that between face to anything... If there is a surface, a continuous blocking will ignore it anyway..."

--> Yes, I set them when I created the model to show the area where the fluid enters...also a case of low concentration...

The rest I must check/try tomorrow.


I wish you a good night respectivly a good start in the day...well, whatever time it is at your place right now
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Old   March 22, 2012, 16:10
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I got the 3d blocking. You did not copy all blocking (initial 2d blocking) to other end?
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Old   March 23, 2012, 05:44
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I did copy the 2D-Blocking so that I got half of the top- surface of cylinder blocked and it worked quite well (model g6). But the extrusion in Z-direction by -70 produces a somehow twisted structure on the bottom side which gives me a bad quality.
--> model g6 mistakes:
a) the copy of the 2d-Blocking "almost" worked correctly. There are only some minor problems: in the copied part there are more bad elements than there are in the original part (picture: copying 2d model g6)
b) I didn't copy the geometry from the top to the bottom - is this maybe the reason for the 3d - extrusion problems? The edges going through the cylinder from top to bottom also need curves or surfaces?

I also experimented a little bit with the periodicity options and improved the mesh a little (model g14) for the 90 degree 2d blocking...well, and then the copy procedure of the 2d blocking doesn't work as it did before...
-->model g14 mistakes:
a) I wasn't able to copy the entire blocking (of the 90° segment) as I was before - Error message (picture 1).
b) The blocking in the copied parts was different to the original blocking. One can see that by the bad elements of the Determinant 2x2x2 (picture: wrong copy blocks).
Attached Images
File Type: png picture1.png (8.0 KB, 16 views)
File Type: jpg wrong copy blocks.jpg (67.9 KB, 30 views)
File Type: jpg copying 2d model g6.jpg (43.5 KB, 21 views)
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Old   March 23, 2012, 08:37
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May be on Monday, I shall work on 3d and try to complete the blocking. And also give some time to comprehend the last post my self.
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Old   March 28, 2012, 08:05
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Hey Far,

I still have problems with the rotate block function even when I follow the instructions: rotate geometry, rotate blocks, update associations. It's the same with the translate function for creating 3D blocking out of my 2D topology (translate blocking).
In both cases the copied mesh isn't equal to the original mesh.

You said that you already created the 3D Mesh. Would you give me your 2D topology you used to create your 3D blocking? I want to test it on my computer. If it works I know that the mistake is something I did before, if it doesn't work the mistake must be somewhere in my settings.


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Last edited by despaired student; March 28, 2012 at 11:05.
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Old   March 28, 2012, 10:14
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Ya, Sure.

I am working on similar problem here, this may be helpful to you.
Suggestion on how to mesh this geometry by structered(Fuel Rod)
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Old   March 28, 2012, 11:17
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Hi,
I've read the thread. When the association-problems appear after "rotate blocks" or "translate block" then it is very likely that these are the same problems.

Could this be a problem of too low computational power or could the amount of copied blocks be too big?
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Old   March 28, 2012, 12:11
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I am thinking to copy few blocks at moment and then associate them properly. And repeating that procedure for other blocks. I shall post those files within day or two.

Quote:
Could this be a problem of too low computational power or could the amount of copied blocks be too big?
I don't think so. Simon is the appropriate person to comment on this aspect.
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Old   March 28, 2012, 15:17
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Quote:
I am thinking to copy few blocks at moment and then associate them properly. And repeating that procedure for other blocks.
I've already tried this procedure - no luck, the same problems.
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Old   March 29, 2012, 03:49
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Quote:
Originally Posted by jeevankumarb View Post
I created 2D block and extruded in either direction and then made the splits.

Suggestion on how to mesh this geometry by structered(Fuel Rod)

This is exactly the method we are using.
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Old   April 3, 2012, 04:19
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I've tried this procedure several times but I always had negative results. I'm very sure that the problem is somehow connected to the size of the blocking because it works with smaller blocking.
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Old   April 17, 2012, 05:57
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Hi Far and other helpers,

I received good results by dissociating all edges and vertices before using "mirror blocks" or "rotate blocks". Afterwards you must/can re-associate the vertices and edges.
In this case there was no pre-mesh shown after extrusion...don't know why? But I'm sure that a pre-mesh had been created because I could create a mesh and by quality control one could see the chosen elements within the geometry so somehow there was a pre-mesh...

It was also possible to extrude the mesh - not the pre-mesh. I'm not sure if this is what you were talking about. In this case I misunderstood the meaning.

Maybe these information help if someone else has similar problems.


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Old   April 17, 2012, 08:46
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Thanks for getting back to us on this.

Your "workaround" of dissociating the blocking from the geometry may be a clue to what ever the problem is. I will mention it to development. I know they recently (in the past release or two) added an option so that copy/rotating the blocking would bring a copy of the associated geometry with it also... I wonder if it is an issue in that code.

As for extrude, we were talking about extruding the blocking faces. It is more flexible than a mesh extrusion. But since it didn't work for you, good job figuring out a work around.

Best regards...

Simon
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Old   April 17, 2012, 09:27
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I should clear my statement at one point: rotate and mirror blocks worked quite good with all edges and vertices dissociated but Create Block >> 2D to 3D >> Method: translate still does not work properly.

Here I had to use the real mesh for extrusion.


@PSYMN: You mentioned the last two versions of ICEM. I'm currently using Icem 14.0 but started with ICEM 13.0

First I tried a way recommended by Far
1. rotate geometry
2. rotate blocking
3. update associations
--> Here most problems occurred within the associations in the O-grids. Other parts were also affected but mainly O-grids.

Last edited by despaired student; April 18, 2012 at 09:31.
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Old   April 18, 2012, 09:39
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The function create blocking>>2D to 3D>>Method translate worked for a value of 70 which is the length of the geometry... but I had to dissociate edges and vertices before doing this...
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Old   April 18, 2012, 21:36
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I was not able to reproduce any problems on my end. Can you be more specific about what was going wrong for you?
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Old   April 25, 2012, 03:44
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I've send you the link to a video-download where you can see the problems.

enclosed are the .tin, .blk files etc.
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Old   March 4, 2013, 11:05
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hi far

I could not find these tutorials. Message I get is that they are removed from website. Can you please see if URL is correct.

regards
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Old   March 4, 2013, 11:22
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Which post# you are referring? Anyhow which tuts you want?
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