[Gmsh] gmsh produces an overrefinement mesh

[Christophe Geuzaine]

> On 8 Apr 2019, at 15:45, Octavio Castillo Reyes <ocastilloreyes at gmail.com> wrote:
> 
> Thank you for your answer. 
> 
> The overrefinement is on points 9, 10, 11, 12, where a size dg*4 is set. However, if I remove the attractor field, the elements are larger at those points. I do not know what I'm forgetting.
> 
> Can you give me some tips?

Your background field

Field[1] = Attractor;
Field[1].NodesList = {101:105};
Field[2] = Threshold;
Field[2].IField = 1;
Field[2].LcMin = 10;
Field[2].LcMax = 100;  // <== 
Field[2].DistMin = 100;
Field[2].DistMax = 300;
Background Field = 2;

requests a mesh size of 100 when you are more than 300 away from the attractor nodes.

Remember than Gmsh uses the minimum value of all mesh size constraints ; so here it will be 100.

Christophe

> 
> Best regards
> 
> 
> 
> 
> 
> On Mon, Apr 8, 2019 at 3:31 PM Christophe Geuzaine <cgeuzaine at uliege.be> wrote:
> 
> 
> > On 8 Apr 2019, at 12:39, Octavio Castillo Reyes <ocastilloreyes at gmail.com> wrote:
> > 
> > Dear all, 
> > 
> > I'm working with a tetrahedral mesh and I would like to add refinement on regions near to some points. However, I do not understand why gmsh produces a mesh over refined (whole domain, which is not desirable).
> > 
> > I attach an example of my .geo file to this email. I hope you have an opportunity to review it and tell me what I'm doing wrong.
> > 
> 
> The sizes are consistent with what you ask, i.e. size = 200 everywhere except close to some points. Where do you see overrefinement?
> 
> Christophe
> 
> > Thank you
> > 
> > 
> > 
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> — 
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science 
> http://www.montefiore.ulg.ac.be/~geuzaine
> 
> 
> 
> <Screenshot from 2019-04-08 15-36-32.png>

— 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science 
http://www.montefiore.ulg.ac.be/~geuzaine