<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 6 Feb 2018, at 11:38, Benedikt Oswald <<a href="mailto:benedikt.oswald@lspr.swiss" class="">benedikt.oswald@lspr.swiss</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Dear gmsh<br class=""><br class="">I create geometries in FreeCAD; I export them either in STEP or BREP format.<br class=""><br class="">Then I import them into gmsh for meshing.<br class=""><br class="">However, gmsh (3.0.7, current daily snapshot) has a tendency to not<br class="">resolve smooth rounded geometry in this case.<br class=""><br class="">Is there an elegant way to teach gmsh how to resolve which portions of<br class="">the STEP/BREP<br class=""><br class="">geometry ?<br class=""></div></div></blockquote><div><br class=""></div><div>You can either do it by hand, by explicitly assigning mesh sizes to points (or by using fields) - see e.g. <font face="Menlo" class=""><a href="https://gitlab.onelab.info/gmsh/gmsh/blob/master/demos/boolean/baffles.geo" class="">https://gitlab.onelab.info/gmsh/gmsh/blob/master/demos/boolean/baffles.geo</a></font></div><div><br class=""></div><div>You could also refine automatically depending on curvature (it’s a bit slow in the current implementation, but has the advantage of being more automatic):</div><div><br class=""></div><div>Merge "ring-rev-100.brep";</div><div>Physical Volume(100) = {1}; // volume ring</div><div>Physical Volume(200) = {2}; // air volume</div><div>Physical Surface(1000) = {7}; // outer truncation boundary</div><div>Mesh.CharacteristicLengthMin = 10;</div><div>Mesh.CharacteristicLengthMax = 100;</div><div>Mesh.CharacteristicLengthFromCurvature = 1;</div><div>Mesh.MinimumCirclePoints = 20; // points per 2*pi</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><blockquote type="cite" class=""><div class=""><div class=""><br class="">I use an intermediate file such as ring-rev-100-aux.geo with this contents:<br class=""><br class="">Merge "ring-rev-100.brep";<br class="">Physical Volume(100) = {1}; // volume ring<br class="">Physical Volume(200) = {2}; // air volume<br class="">Physical Surface(1000) = {7}; // outer truncation boundary<br class=""><br class="">to assign physical tags to volumes & surface ?<br class=""><br class="">Greetings & thanks, Benedikt<br class=""><br class=""><br class=""><br class=""><br class="">----------------------------------------------------------------------------------------------------------------------<br class="">Dr. sc. techn. Benedikt Oswald - first engineer - LSPR AG - phone +41 43 366 90 74<br class="">Grubenstrasse 9, CH-8045 Zürich, <a href="mailto:benedikt.oswald@lspr.swiss" class="">benedikt.oswald@lspr.swiss</a><br class="">----------------------------------------------------------------------------------------------------------------------<br class=""><br class=""><span id="cid:05A83158-0FE5-4C85-97D1-77F7ACEBF5F6@home"><ring-rev-100.brep></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></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>
</div>
<br class=""></body></html>