<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252">
</head>
<body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div><br>
</div>
<div>Hello Isabel,</div>
<div><br>
</div>
<div>it seems to me that the model is correct</div>
<div>and that the Neumann B.C. is correctly taken into account.</div>
<div><br>
</div>
<div>The formulation, however is a bit unusual.</div>
<div><br>
</div>
<div>As you did not say what application it is, </div>
<div>I shall assume it be a thermal problem. </div>
<div><br>
</div>
<div>The Dirichlet B.C. on the side of the cylinder </div>
<div>imposes a normal/radial heat flux. </div>
<div>The Neumann B.C. on the planar faces, </div>
<div>on the other hand, </div>
<div>imposes an axial heat flux (in X direction).</div>
<div>The two B.C’s are thus kind of contradictory </div>
<div>on the edges of the cylindre,</div>
<div>hence the strange looking of the computed gradient of temperature (ValueDNVolume).</div>
<div><br>
</div>
<div>Note also that the PostProcessing quantity</div>
<div><br>
</div>
<div> { Name ValueDNSurfaces; Value { Local { [ {d N} ]; In Superficies; Jacobian Sur; Integration Int;} } }</div>
<div><br>
</div>
<div>only returns the tangential part of the gradient</div>
<div>(the one that lives in the surface).</div>
<div>This might be the reason why you felt</div>
<div>the Neumann B.C. was not taken into consideration. </div>
<div><br>
</div>
<div>Hope this helps,</div>
<div><br>
</div>
<div>Fr. </div>
<div><br>
</div>
<br>
<div>
<div>Le 10 oct. 2019 à 13:59, Isabel Martínez <<a href="mailto:isabelXXI21@hotmail.com">isabelXXI21@hotmail.com</a>> a écrit :</div>
<br class="Apple-interchange-newline">
<blockquote type="cite">
<div dir="ltr" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);">
<span>Dear all:<br>
</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);">
<div><br>
</div>
<div>This is the first time I am using getdp. I am trying to solve a Laplace problem with mixed boundary conditions in a cylinder. The equations are:<br>
</div>
<div><br>
</div>
<div>- Laplacian N = 0 inside the cylinder.<br>
</div>
<div><br>
</div>
<div>N = 0 on the side of the cylinder.<br>
</div>
<div>grad N * normal[] = - CompX[Normal[]] on the bases of the cylinder.<br>
</div>
<div><br>
</div>
<div>I have my .geo and .pro files, but when getdp computes the solution the Neumann condition is not fulfilled. I checked the normal vectors with the gui of gmsh and the postprocesing of getdp and they looked good. I tried with different ways of define my
geometry but it gives me the same results.<br>
</div>
<div><br>
</div>
<div>I put the Dirichlet condition as a constraint and the weak formulation is:<br>
</div>
<div>[Dof{d N} ,{d N} ]_inside the cylinder<br>
</div>
<div>+ [CompX[Normal[]] ,{N} ]_on the bases of the cylinder.<br>
</div>
<div><br>
</div>
<div>I am using getdp-3.2.0 and gmsh-4.4.1 for Windows64. I also tried with the version from the 1st of October of 2019 of ONELAB.<br>
</div>
<div><br>
</div>
<div>I can't find what is wrong, I would be thankful if someone can help me. I attached the .geo and .pro files.<br>
</div>
<div><br>
</div>
<div>Thank you in advance.<br>
</div>
<div>Isabel.<br>
</div>
<span></span><br>
</div>
<span><Geo.geo></span><span><Pro.pro></span>_______________________________________________<br>
getdp mailing list<br>
<a href="mailto:getdp@onelab.info">getdp@onelab.info</a><br>
<a href="https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fonelab.info%2Fmailman%2Flistinfo%2Fgetdp&data=02%7C01%7C%7C58a0e7b3c60849ec66b108d74e059809%7C7ab090d4fa2e4ecfbc7c4127b4d582ec%7C0%7C0%7C637063658844341350&sdata=Mo5OEQmr9erw1j8n50K%2Bq74TXK3soK8V91XsW2qBDcQ%3D&reserved=0">https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Fonelab.info%2Fmailman%2Flistinfo%2Fgetdp&data=02%7C01%7C%7C58a0e7b3c60849ec66b108d74e059809%7C7ab090d4fa2e4ecfbc7c4127b4d582ec%7C0%7C0%7C637063658844341350&sdata=Mo5OEQmr9erw1j8n50K%2Bq74TXK3soK8V91XsW2qBDcQ%3D&reserved=0</a></div>
</blockquote>
</div>
<br>
<div apple-content-edited="true">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div>
<div style="orphans: 2; widows: 2;">
<div>--</div>
<div>François Henrotte Dr Ir - <span style="text-align: -webkit-auto;"><a href="mailto:francois.henrotte@uclouvain.be">francois.henrotte@uclouvain.be</a></span><span style="text-align: -webkit-auto;"> - </span><span style="text-align: -webkit-auto;"><a href="mailto:francois.henrotte@uliege.be">francois.henrotte@uliege.be</a> </span></div>
<div>UCLouvain - Bât. Euler a.217 - Av. G. Lemaître 4-6 , <span style="text-align: -webkit-auto;">B-1348 Louvain-la-Neuve - </span><span style="text-align: -webkit-auto;">+32(0)10 47 23 64 </span></div>
<div><span style="text-align: -webkit-auto;">ULiège - Institut Montefiore I154 - Allée de la Découverte 10, B-4000 Liège - +32(0)4 366 37 36 </span></div>
<div><span style="text-align: -webkit-auto;"><br>
</span></div>
</div>
</div>
<div><span style="text-align: -webkit-auto;"><br>
</span></div>
</div>
<br class="Apple-interchange-newline">
</div>
<br class="Apple-interchange-newline">
<br class="Apple-interchange-newline">
</div>
<br>
</body>
</html>