<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 25 May 2018, at 16:26, Quentin Goestchel <<a href="mailto:quentin.goestchel@ens-cachan.fr" class="">quentin.goestchel@ens-cachan.fr</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
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<div text="#000000" bgcolor="#FFFFFF" class=""><p class="">Dear Sir or Madam,</p><p class=""> I would like to thank you for the great work which has been done
to develop the open-source Gmsh software. <br class="">
</p><p class="">I am currently working on a 3D numerical method and I think I
have found a bug in the 3D meshing algorithm. I was trying to
generate a transfinite bulk in a mesh (to have a constant
orthogonality of the elements), and an unstructured layer around
it, as shown in the enclosed "sphereTransfinite.png". <br class=""></p></div></div></blockquote><div><br class=""></div><div>This is "normal" the (non-recombined) 3D transfinite algorithm does not try to enforce the compatibility between the volume and surface meshes. It's actually impossible without modifying the 2D mesh a posteriori in some configuration (since we also generate the 2D mesh first). You should specify the corners of the transfinite interpolation in the right order to have the match.</div><div><br class=""></div><div>PS: Using Extrusion instead of Transfinite, Gmsh will try to perform the modifications automatically.</div><br class=""><blockquote type="cite" class=""><div class=""><div text="#000000" bgcolor="#FFFFFF" class=""><p class="">
</p><p class="">Everything was going fine until I noticed a big error on my
discretized spherical surface, computed with the sum of the areas
of the boundary faces. I found out that my code was unable to find
the neighbours of many tetrahedrons around the bulk mesh because
many faces were not matching but crossing each other edges, as
shown in sphereTransfinite_err.png . <br class="">
</p><p class="">I didn't find any topics about such problem so I assume that you
didn't know about it, but I might be wrong. <br class="">
</p><p class="">Best regards, <br class="">
</p>
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<span style="font-size: 12pt;" class="">Quentin
Goestchel</span>
<span class="nd" style="font-size: 17px;"> | </span><span class="nl"><i class="">Etudiant - Année ARPE </i></span>
<br class="nd">
Département Génie Civil <br class="">
<a href="tel:+33683755753" style="color:
#00778b;text-decoration: none;" class="">+33(0)6
83 75 57 53</a>
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<span class="nl" style="text-align:
left;font-size: 9pt;"><a href="mailto:prenom.nom@ens-paris-saclay.fr" style="color: #00778b;text-decoration: none;" class=""><span style="color:
#00778b;white-space: nowrap;" class="">quentin.goestchel<span class="">@</span>ens-paris-saclay<span class="">.</span>fr</span></a>
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<span id="cid:73485356-7987-4870-88A0-75851CAA9770@home"><sphereTransfinite.png></span><span id="cid:D0F9A114-3082-4C96-983E-5226B0D70FC2@home"><sphereTransfinite_err.png></span><span id="cid:2D9AFF67-924E-47A8-ABB3-E17A1DC4C7B5@home"><sphereTransfinite.geo></span>_______________________________________________<br class="">gmsh mailing list<br class=""><a href="mailto:gmsh@onelab.info" class="">gmsh@onelab.info</a><br class="">http://onelab.info/mailman/listinfo/gmsh<br class=""></div></blockquote></div><br class=""><div class="">
<div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">— </div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Prof. Christophe Geuzaine<br class="">University of Liege, Electrical Engineering and Computer Science <br class=""><a href="http://www.montefiore.ulg.ac.be/~geuzaine" class="">http://www.montefiore.ulg.ac.be/~geuzaine</a><br class=""><br class="">Free software: http://gmsh.info | http://getdp.info | http://onelab.info</div></div>
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