Never mind, just found out, it depends on the characteristic length of the points used to generate the surfaces...
-----Messaggio originale----- Da: gmsh [mailto:gmsh-boun...@ace20.montefiore.ulg.ac.be] Per conto di Alessandro Vicini Inviato: giovedì 22 novembre 2018 09:44 A: Christophe Geuzaine Cc: gmsh@onelab.info Oggetto: [Gmsh] R: Problems with 2D mesh Ok, got it. Another question then on the behavior of Mesh.CharacteristicLengthExtendFromBoundary: why does it also affects the mesh density on the outer surface (where no transfinite lines are set)? Thank you. Alessandro -----Messaggio originale----- Da: Christophe Geuzaine [mailto:cgeuza...@uliege.be] Inviato: mercoledì 21 novembre 2018 17:32 A: Alessandro Vicini Cc: gmsh@onelab.info Oggetto: Re: [Gmsh] Problems with 2D mesh > On 20 Nov 2018, at 09:10, Alessandro Vicini <alessandro.vic...@sitael.com> > wrote: > > Hello Christophe, > > the surface mesh is wrong if you set > Mesh.CharacteristicLengthExtendFromBoundary = 0. I have just tried > latest version 4.0.5, but the behavior is the same… The surface mesh looks correct to me: you constrain the size of the line elements on the edges of the parallelepipeds with Transfinite constraints, but the mesh size field computed by attractor_TestCase.geo on these parallelepipeds is much larger than this constraint (see the picture I sent in my previous mail). You thus get refined edges, but the largest possible surface elements connected to them. Remove your Transfinite constraints and you will obtain the correct uniform (but very coarse) mesh on the parallelepipeds. Setting Mesh.CharacteristicLengthExtendFromBoundary = 1 will use the edge size constraint to set the size of the triangles - discarding your coarser mesh size specification done in attractor_TestCase.geo, leading to a denser, uniform mesh. So everything seems to be working as expected... > > A. > > > Da: Christophe Geuzaine [mailto:cgeuza...@uliege.be] > Inviato: lunedì 19 novembre 2018 19:41 > A: Alessandro Vicini > Cc: gmsh@onelab.info > Oggetto: Re: [Gmsh] Problems with 2D mesh > > > > > On 19 Nov 2018, at 12:25, Alessandro Vicini <alessandro.vic...@sitael.com> > wrote: > > > With the attached geo file (TestCase) I have a problem in the 2D mesh > of some of the internal faces (see attached picture) if I set > Mesh.CharacteristicLengthExtendFromBoundary = 0 (which is what I would like > to do), regardless of the meshing algorithm. The mesh is ok when > Mesh.CharacteristicLengthExtendFromBoundary = 1. I'm using v4.0.1. Is there a > way to solve this? Thank you. > > > The mesh size looks OK to me given your mesh size field (I've tested with > Gmsh 4.0.5): > > > <image001.png> > > > > A.V. > <TestCase.geo><attractor_TestCase.geo><TestCase.jpg>__________________ > _____________________________ > gmsh mailing list > gmsh@onelab.info > > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fonelab.info%2Fmailman%2Fl > istinfo%2Fgmsh&e=69b77ccd&h=f5c42a45&f=y&p=y > > — > Prof. Christophe Geuzaine > University of Liege, Electrical Engineering and Computer Science > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fwww.montefiore.ulg.ac.be% > 2F~geuzaine&e=69b77ccd&h=e4f3613a&f=y&p=y > > Free software: > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fgmsh.info&e=69b77ccd&h=ec > 49fb48&f=y&p=y | > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fgetdp.info&e=69b77ccd&h=0 > e857c64&f=y&p=y | > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fonelab.info&e=69b77ccd&h= > e3a8f919&f=y&p=y > > _______________________________________________ > gmsh mailing list > gmsh@onelab.info > > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fonelab.info%2Fmailman%2Fl > istinfo%2Fgmsh&e=69b77ccd&h=f5c42a45&f=y&p=y — Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science https://urlsand.esvalabs.com/?u=http%3A%2F%2Fwww.montefiore.ulg.ac.be%2F~geuzaine&e=69b77ccd&h=e4f3613a&f=y&p=y Free software: https://urlsand.esvalabs.com/?u=http%3A%2F%2Fgmsh.info&e=69b77ccd&h=ec49fb48&f=y&p=y | https://urlsand.esvalabs.com/?u=http%3A%2F%2Fgetdp.info&e=69b77ccd&h=0e857c64&f=y&p=y | https://urlsand.esvalabs.com/?u=http%3A%2F%2Fonelab.info&e=69b77ccd&h=e3a8f919&f=y&p=y _______________________________________________ gmsh mailing list gmsh@onelab.info https://urlsand.esvalabs.com/?u=http%3A%2F%2Fonelab.info%2Fmailman%2Flistinfo%2Fgmsh&e=69b77ccd&h=f5c42a45&f=y&p=y _______________________________________________ gmsh mailing list gmsh@onelab.info http://onelab.info/mailman/listinfo/gmsh
