Zenker, Dr. Matthias wrote: > Of course. Here it is. > > BTW, I use gmsh 2.2.6 on a WIN XP SP 2, Pentium 4, 3.2 GHz, 1.5 GB RAM > computer. >
The default random perturbation factor seems to be a bit small in your case. The following (increased "-rand" from "1.e-9" to "1.e-7") gmsh small_cl.geo -2 -rand 1.e-7 seems to work just fine, but I had to stop it before the end due to insufficient memory on my laptop. Multiplying all the element sizes by 3 and using the faster del2d algorithm gmsh small_cl.geo -2 -rand 1.e-7 -clscale 3 -algo del2d produced a nice mesh with about 23 million triangles. > If I could force gmsh not to ignore the cl of the spline control points, > it would probably be faster for such a case (if it wouldn't crash). Is > there a trick to do that? Would it help to put isolated points with the > desired cl at the desired location? You should probably use Fields to fine-tune the element sizes. There are some examples on the mailing list, as well as in demos/fields.geo. > > Thank you and best regards, > > Matthias > >> -----Original Message----- >> From: Christophe Geuzaine [mailto:[email protected]] >> Sent: Monday, December 15, 2008 1:07 PM >> To: Zenker, Dr. Matthias >> Cc: [email protected] >> Subject: Re: [Gmsh] lower limit for characteristic length >> >> Zenker, Dr. Matthias wrote: >>> Hi there, >>> >>> the question remains: is there a lower limit for the characteristic >>> length cl, and why does gmsh crash when some points have a small cl? >> It shouldn't crash, except when "cl" divided by the overall >> size of model is getting close to machine accuracy (or more >> accurately, close to the value of the random pertutbation >> used in the meshing algorithms, which is 1e-9 by default). >> >> Could you send a file that shows the problem? >> >> >>> I would like to add another one: Is it possible that gmsh >> ignores the >>> cl of the control points of a spline except for the first and last >>> one? If >> That's what Gmsh does: the cls of the control points are ignored. >> >> >> >>> so, is there a way to force gmsh to take into account the cl of the >>> intermediate points also? >>> >>> Best regards, >>> >>> Matthias >>> >>> >> -------------------------------------------------------------- >> ---------- >>> *From:* [email protected] [mailto:[email protected]] *On >>> Behalf Of *Zenker, Dr. Matthias >>> *Sent:* Monday, November 17, 2008 10:49 AM >>> *To:* [email protected] >>> *Subject:* Re: [Gmsh] lower limit for characteristic length >>> >>> I was wrong, it crashes also for cl=0.0005 (but after a >> looong time, >>> and with a runtime error). >>> >>> >> -------------------------------------------------------------- >> ---------- >>> *From:* [email protected] >> [mailto:[email protected]] *On >>> Behalf Of *Zenker, Dr. Matthias >>> *Sent:* Monday, November 17, 2008 10:16 AM >>> *To:* [email protected] >>> *Subject:* [Gmsh] lower limit for characteristic length >>> >>> Hi, >>> >>> I wonder if there is a lower limit for the characteristic >>> length. I have a rather simple 2D geometry, and if >> I set the cl >>> for just two points to 0.0001, gmsh crashes during >> the meshing >>> after having given the error message "3 identical points in >>> Qtest". The .gmsh-errors file is not written. With >> cl=0.0005, >>> this does not happen (but it takes veeery long to >> compute the mesh). >>> Best regards, >>> >>> Matthias >>> >>> >> ---------------------------------------------------------------- >>> ERBE Elektromedizin GmbH >>> Dr.rer.nat. Matthias Zenker >>> Dipl. Phys. >>> Grundlagenentwicklung Technologie >>> Waldhoernlestrasse 17 >>> D-72072 Tuebingen >>> Tel.: + 49 (0) 7071 - 755 226 >>> Fax: + 49 (0) 7071 - 755 5226 >>> E-Mail: <_mailto:[email protected]_> >>> URL: _http://www.ERBE-med.de_ >>> >>> ---------------------------------------------------------------- >>> >>> >>> >>> >>> >>> ERBE Elektromedizin GmbH >>> Firmensitz: 72072 Tuebingen >>> Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede >>> Registergericht: Stuttgart HRB 380137 >>> >>> >>> >>> >>> >>> >>> ERBE Elektromedizin GmbH >>> Firmensitz: 72072 Tuebingen >>> Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede >>> Registergericht: Stuttgart HRB 380137 >>> >>> >>> >>> >>> >>> >>> ERBE Elektromedizin GmbH >>> Firmensitz: 72072 Tuebingen >>> Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede >>> Registergericht: Stuttgart HRB 380137 >>> >>> >>> >>> >> ---------------------------------------------------------------------- >>> -- >>> >>> _______________________________________________ >>> gmsh mailing list >>> [email protected] >>> http://www.geuz.org/mailman/listinfo/gmsh >> >> -- >> Prof. Christophe Geuzaine >> University of Liege, Electrical Engineering and Computer >> Science http://www.montefiore.ulg.ac.be/~geuzaine >> > > _____________________________________________________________________ > ERBE Elektromedizin GmbH > Firmensitz: 72072 Tuebingen > Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede > Registergericht: Stuttgart HRB 380137 > > > > ------------------------------------------------------------------------ > > _______________________________________________ > gmsh mailing list > [email protected] > http://www.geuz.org/mailman/listinfo/gmsh -- Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
