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<div><div><div dir="ltr" style="color: rgb(38, 40, 42);">Hello Christophe,</div><div dir="ltr" style="color: rgb(38, 40, 42);"><br clear="none"></div><div dir="ltr" style="color: rgb(38, 40, 42);">there appear to be problems with my email formatting.</div><div dir="ltr" style="color: rgb(38, 40, 42);"><br clear="none"></div><div dir="ltr" style="color: rgb(38, 40, 42);">To avoid that I re-send the previous message as a file (hopefully this should work)<br clear="none"></div><div dir="ltr" style="color: rgb(38, 40, 42);"><br clear="none"></div><div dir="ltr" style="color: rgb(38, 40, 42);">Regards,</div><div dir="ltr" style="color: rgb(38, 40, 42);"><br clear="none"></div><div dir="ltr" style="color: rgb(38, 40, 42);">Marco</div><div dir="ltr" data-setdir="false"><br></div></div></div><div><br></div>
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Il mercoledì 4 novembre 2020, 09:14:51 CET, Christophe Geuzaine <cgeuzaine@uliege.be> ha scritto:
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<div><div dir="ltr"><br clear="none"><br clear="none">> On 22 Oct 2020, at 12:56, Marco Antolovic <<a shape="rect" href="mailto:marco_antolovic@yahoo.it" rel="nofollow" target="_blank">marco_antolovic@yahoo.it</a>> wrote:<br clear="none">> <br clear="none">> Hi all,<br clear="none">> <br clear="none">> I'm trying to find the best way to approach the following problem:<br clear="none">> <br clear="none">> I have a parallelepiped with the edge alone z much smaller than that along x and y (this is typical, for example, <br clear="none">> for PCB traces) and I would like to guarantee, in the volume, a predefined number of layers (np_layers) along z<br clear="none">> edge.<br clear="none">> <br clear="none">> If I build the structure in gmsh this is quite simple to obtain by saying:<br clear="none">> <br clear="none">> SetFactory("OpenCASCADE");<br clear="none">> thickness = 140e-6;<br clear="none">> nr_layers = 4;<br clear="none">> surf=newreg;<br clear="none">> Rectangle(surf)={.001,0,0,.001,.001,0};<br clear="none">> Extruded_surf() = Extrude { 0,0, thickness } { Surface{surf}; Layers{nr_layers}; Recombine;};<br clear="none">> <br clear="none">> But how can I apply this in case the parallelepiped is coming from a step file? The command above<br clear="none">> (Extrude{...}{... Layers{}}) can't be used.<br clear="none"><br clear="none">Indeed, we would need to "reverse engineer" the fact that the volume has indeed been created by extrusion. See<br clear="none"><br clear="none"><a shape="rect" href="https://gitlab.onelab.info/gmsh/gmsh/-/issues/929" rel="nofollow" target="_blank">https://gitlab.onelab.info/gmsh/gmsh/-/issues/929</a><br clear="none"><br clear="none">for the issue tracking this feature request.<br clear="none"><br clear="none">Christophe<div class="ydpfc6e8dbcyqt7698873874" id="ydpfc6e8dbcyqtfd84497"><br clear="none"><br clear="none"><br clear="none">> <br clear="none">> I was thinking about slicing the Volume with some planes (see example below)<br clear="none">> <br clear="none">> SetFactory("OpenCASCADE");<br clear="none">> thickness = 140e-6;<br clear="none">> nr_layers = 4;<br clear="none">> surf=newreg;<br clear="none">> Rectangle(surf)={.001,0,0,.001,.001,0};<br clear="none">> Extruded_surf() = Extrude { 0,0, thickness } { Surface{surf};};<br clear="none">> vol() = Extruded_surf(1);<br clear="none">> For i In {1:nr_layers-1}<br clear="none">> surf1(i-1)=newreg;<br clear="none">> Rectangle(surf1(i-1)) = {.001, 0, thickness/nr_layers*i, .001, .001};<br clear="none">> EndFor<br clear="none">> results() = BooleanFragments{Volume{vol()};Delete;}{Surface{surf1()}; Delete;};<br clear="none">> <br clear="none">> but when trying to recombine the triangles in the layers I get the following error:<br clear="none">> <br clear="none">> Error : Pyramid top vertex already classified on volume 2 (!= 3) - non-manifold quad boundaries not supported<br clear="none">> yet<br clear="none">> <br clear="none">> Any suggestion on how to address the issue is much appreciated.<br clear="none">> <br clear="none">> Regards,<br clear="none">> <br clear="none">> Marco</div><br clear="none">> <br clear="none">> _______________________________________________<br clear="none">> gmsh mailing list<br clear="none">> <a shape="rect" href="mailto:gmsh@onelab.info" rel="nofollow" target="_blank">gmsh@onelab.info</a><br clear="none">> <a shape="rect" href="http://onelab.info/mailman/listinfo/gmsh" rel="nofollow" target="_blank">http://onelab.info/mailman/listinfo/gmsh</a><br clear="none"><br clear="none">— <br clear="none">Prof. Christophe Geuzaine<br clear="none">University of Liege, Electrical Engineering and Computer Science <br clear="none"><a shape="rect" href="http://people.montefiore.ulg.ac.be/geuzaine" rel="nofollow" target="_blank">http://people.montefiore.ulg.ac.be/geuzaine</a><div class="ydpfc6e8dbcyqt7698873874" id="ydpfc6e8dbcyqtfd81701"><br clear="none"><br clear="none"><br clear="none"><br clear="none"></div></div></div>
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