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<p>Dear Christoph,</p>
<p><br>
</p>
<p>We try to mesh a three dimensional fracture embedded in a
cylindrically shaped rock volume.</p>
<p>We can mesh the fracture and the cylinder separately but for
later use as input for a numerical simulation, we have to
subtract or intersect the two volumes.</p>
<p><br>
</p>
<p>Unfortunately, gmsh provides an error message regarding our
surface loop.</p>
<p>Gmsh complains that our surface loop is not a valid openCascade
entity.</p>
<p><br>
</p>
<p>Do you have any suggestion to perform boolean operation with our
geometries?</p>
<p>Please find attached our input geo-file.</p>
<p><br>
</p>
<p>kind regards</p>
<p><br>
</p>
<p>Guido<br>
</p>
<p><br>
</p>
<p><img src="cid:part1.80E60E8D.114EF88B@gfz-potsdam.de" alt=""></p>
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