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-   -   meshing process stops (after surf meshing?) (http://www.cfd-online.com/Forums/openfoam-meshing-open/84105-meshing-process-stops-after-surf-meshing.html)

vaina74 January 20, 2011 05:15

meshing process stops (after surf meshing?)
 
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Hi everybody.

I use Netgen 4.9.13 on Ubuntu 10.04 LTS 64bit. When I launch a meshing process, it often stops after the surface meshing stage (I think). It usually (but not only) happens with refinement criteria finer than 'coarse'. Today it stops with less than 200,000 surf elementes. How can I get rid of that? My laptop is a Dell Precision M4400: has an Intel Core 2 Duo T9550 (2.66 GHz), 4 Gb RAM, a NVIDIA Quadro FX 770M.
I attach the .brep geometry.

vaina74 January 20, 2011 10:21

I fixed the problem. Probably Netgen hates faces with high curvaturers in many directions, so I 'fragmented' them. Now Netgen sees the bottom of the process.

umassche May 26, 2011 16:33

Hi, I have the same problem with Netgen crashing at the surface meshing step. What do u mean u "fragmented" them? U mean by triangulating the geometry?

vaina74 May 27, 2011 01:33

1 Attachment(s)
NETGEN crashes for a lot of reasons :-)
Anyway, I meant that NETGEN doesn't like highly curved surfaces, so I had to partition them and obtain more (smaller) faces. In my case, I worked with propellers and had to separate the blade suction side from pressure side and each of them is partitioned (see the pic).
But I can't understand what's your problem. Maybe your geometry is not so good, I need more informations about that.

umassche May 27, 2011 02:24

my geometry is an STL surface geometry file of a pipe inside a pipe. During the surface meshing step NetGen crashes with the error message "Segmentation fault". However meshing completes without this problem when I try the same thing on a MacbookPro with 64 bit version. Mine is a Dell Inspiron 1525 with a simple nothing-fancy VGA and 3GB ram with Ubuntu 11.04 and runs the 32 bit version. Other STL files that I have found (even complex looking ones) in tutorials etc. work fine on my Dell when meshing.

vaina74 May 27, 2011 02:32

Maybe your problem depends on your system architecture. I don't know how much heavy is your mesh, but read post #7 here.


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