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June 6, 2012, 10:48 |
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#21 |
Super Moderator
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I am not happy with mesh. I dont know why mesh goes circular to square shape and then again square to circular. In this type of geometry where internal and external parts have similar shape, we should have the very good looking circular mesh. Any idea why this is happing?
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June 7, 2012, 01:37 |
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#22 |
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
I Followed it but the main problem is the bottom circle of the hemisphere. It itself need a 2D O-grid but in 3D blocking it is not possible as I know.
here is a 2D o-grid for a circle. Last edited by reza45000; June 7, 2012 at 03:23. |
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June 7, 2012, 03:07 |
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#23 | |
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
Quote:
as you mentioned it is not a good one, look at the min angle: we have 0-9 degree cells. |
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June 7, 2012, 03:35 |
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#24 |
Super Moderator
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No, It is not true. You must have activated solid part. I was talking about the general mesh shape otherwise quality is good and angle is higher than 40.
I guess we are on different track. I guess circle should be hollow. Can you describe your problem again with geometry pics to be modelled and some additional description? |
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June 7, 2012, 04:49 |
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#25 | |
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
Quote:
and we need farfield as I created in the geometry file. |
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June 7, 2012, 05:30 |
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#26 |
Super Moderator
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Ok , got it. Nevertheless, we still make the hemishpere as hollow since fluid is not going inside.
In this case the far feild on the other side should be rectangular in shape to ease the meshing. |
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June 7, 2012, 05:45 |
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#27 |
Super Moderator
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In the mean time for hemisphere section, use strategy we have just discussed. And in the other part with flat end (cylindrical enclosure), use simple topology and then create o-grid inside circular base all the way to end of cylindrical domain. Got it?
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June 7, 2012, 06:41 |
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#28 | ||
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
Quote:
Quote:
I think my problem is the mesh on the bottom of hemisphere (as I showed in previous comments) that we should make a 2d o-grid on that circle but I couldn't do it. If you have time to make a correct blocking, I will appreciate. |
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June 8, 2012, 08:21 |
Done
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#30 |
Super Moderator
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Done. It has some tricky part, when I was trying to snap vertices to hemisphere. Unlike the space cube tutorial where all things were done nicely with associate vertex to point on the inner cube, but this is not the case with this problem.
Enjoy and let me know if you get same problem as discussed above. |
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June 11, 2012, 03:40 |
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#32 | |
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
Quote:
Thanks again. |
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June 11, 2012, 06:24 |
I learn to feel the ICEM
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#33 |
Super Moderator
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I guess, now I am feeling the ICEM from heart. For example in this case if you snap the outer block first and then inner block, you will get the mesh problems as I have stated previously. You have to snap vertices at once. So make all oblocks, change material and snap the vertices.
Mine vertices for inner block were placed at Y= 1.9, while Reza's vertices (same vertices) were found to be at Y = 2.9. When used above trick or method, I have also got the vertices at Y = 2.9. Have fun. |
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June 11, 2012, 06:26 |
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#34 | |
Super Moderator
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Quote:
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June 11, 2012, 07:46 |
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#35 |
New Member
reza
Join Date: May 2012
Posts: 7
Rep Power: 13 |
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July 8, 2012, 04:21 |
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#37 | |
Super Moderator
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Quote:
I found the reason for this. This is because I have forgot to switch back transfinite degree = Quadratic to transfinite degree = linear (linear is default option), so ICEM made it my default method and I was wondering for weeks that this is bug in ICEM. But now things are good . Mid and outlet plane with quadratic option: Mid and outlet plane with linear option |
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