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<p class="MsoNormal"><span style="color:#1F497D">Hi all,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I’m giving it another try…I am still looking for a solution to locally refine a mesh created from an STL 3D surface.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Since I am using the Netgen algorithm for meshing, I was wondering whether there is a possibility to pass a Netgen msz-File and accomplish the desired behavior in this way.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Else I’d just need a hint on how to include Points (defining local mesh size) into a Volume defined by a 3D surface loaded from an STL file (see my previous message).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Many thanks even for the slightest hint!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Fabian<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> gmsh [mailto:gmsh-bounces@ace20.montefiore.ulg.ac.be]
<b>On Behalf Of </b>BRAUN Fabian<br>
<b>Sent:</b> 28 July 2014 15:16<br>
<b>To:</b> gmsh@geuz.org<br>
<b>Subject:</b> [Gmsh] local mesh refinement of STL<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dear all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For bio-impedance simulations I am creating a 3D volume mesh (of a human thorax) out of a 3D surface mesh from an STL file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Now I would like my volume mesh to be finer in certain regions (e.g. aorta and heart regions have 10-fold finer mesh than the other elements).<o:p></o:p></p>
<p class="MsoNormal" style="text-autospace:none">What I’ve tried after having read the documentation (<a href="http://geuz.org/gmsh/doc/texinfo/gmsh.html#Specifying-mesh-element-sizes">http://geuz.org/gmsh/doc/texinfo/gmsh.html#Specifying-mesh-element-sizes</a>)
is to seed the regions which I want to be meshed finer with a grid of points as follows:
<o:p></o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">Point(1)={x1,y1,z1,MaxSizeLocalRefined};<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">…<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">Point(N)={xN,yN,zN,MaxSizeLocalRefined};<o:p></o:p></span></p>
<p class="MsoNormal">However, I am unsure of how to embed these points into the volume of the STL mesh. (I guess they somehow need to be included into the Volume(1).)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Above there is the initial .geo file (without the point grid) which is automatically generated by the EIT EIDORS toolbox’ function place_elec_on_surf.m (<a href="http://eidors3d.sourceforge.net/doc/eidors/models/place_elec_on_surf.html">http://eidors3d.sourceforge.net/doc/eidors/models/place_elec_on_surf.html</a>).
<o:p></o:p></p>
<p class="MsoNormal">--------start geo file------<o:p></o:p></p>
<p class="MsoNormal">Merge "thorax.stl";<o:p></o:p></p>
<p class="MsoNormal">Surface Loop(1) = {1};<o:p></o:p></p>
<p class="MsoNormal">Volume(1) = {1};<o:p></o:p></p>
<p class="MsoNormal">Physical Volume('object') = {1};<o:p></o:p></p>
<p class="MsoNormal">Mesh.Algorithm3D=4;<o:p></o:p></p>
<p class="MsoNormal">Mesh.OptimizeNetgen=1;<o:p></o:p></p>
<p class="MsoNormal">-------end geo file-------<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any suggestions of how to modify the above geo file to force a finer mesh in certain regions?<o:p></o:p></p>
<p class="MsoNormal"><br>
Thank you very much for your hints in advance!<o:p></o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Fabian<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">PS: I’m running gmsh 2.8.5 on a Win64 machine<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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