<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div data-marker="__QUOTED_TEXT__"><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div>Hi Ernesto,<br></div><div><br data-mce-bogus="1"></div><div>Thank you very much for your advice!<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>I would like to enforce a B_theta boundary condition, which should correspond to KAXIS and MAGZ_VAR as you suggested. This seems consistent with the output of the standard NohCylindrical test problem having only MAGZ_VAR be non-zero.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>I tested putting ivar == MAGX_VAR just in case, to no avail. I am now starting to suspect that, by using the unsplit staggered mesh, I perhaps need to enforce a condition on the cell faces.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>Any other advice or suggestions is much appreciated!<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>Cheers,<br data-mce-bogus="1"></div><div>Greg.</div><div><br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><hr id="zwchr"><div><b>From: </b>"Ernesto Zurbriggen" <ezurbriggen@unc.edu.ar><br><b>To: </b>"flash-users" <flash-users@flash.uchicago.edu><br><b>Sent: </b>Friday, 24 August, 2018 16:59:00<br><b>Subject: </b>Re: [FLASH-USERS] Magnetic field boundary condition for NohCylindrical test problem<br></div><br><div><div dir="ltr">Hi Greg! <div>I'm not in the details, but remember that in cylindrical geometry (IAXIS,JAXIS,KAXIS)=(r,z,theta). </div><br><div>>>I am using the Unsplit Staggered Mesh MHD solver, and have included a modified Grid_bcApplyToRegion.F90 that alters the standard "reflect" condition on the HIGH face of IAXIS to: <br></div><div>So, if you would like to modify the BC on the HIGH face of IAXIS, </div><br><div>>> if(ivar == MAGZ_VAR) regionData(k-i,1:je,1:ke,ivar)= 1.0 <br></div><div>maybe you should put ivar == MAGX_VAR instead. </div><br><div>Best!</div><br><div>Ernesto </div><br class="gmail-Apple-interchange-newline"></div><br><div class="gmail_quote"><div dir="ltr">El vie., 24 ago. 2018 a las 5:48, Boyle, Gregory (<<a href="mailto:gregory.boyle@desy.de" target="_blank">gregory.boyle@desy.de</a>>) escribió:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear FLASH community,<br>
<br>
I am attempting to modify the the 2D NohCylindrical test problem (32.2.4) to include a permanent B_{\theta} condition at rightmost r boundary. This is a first step towards including the effect of a longitudinal current.<br>
<br>
I am using the Unsplit Staggered Mesh MHD solver, and have included a modified Grid_bcApplyToRegion.F90 that alters the standard "reflect" condition on the HIGH face of IAXIS to:<br>
<br>
k = 2*guard+1<br>
if(isFace)k=k+1<br>
do i = 1,guard<br>
regionData(k-i,1:je,1:ke,ivar)= regionData(i,1:je,1:ke,ivar)*sign<br>
if(ivar == MAGZ_VAR) regionData(k-i,1:je,1:ke,ivar)= 1.0<br>
end do<br>
<br>
However, when I look at the output it seems the condition of setting MAGZ_VAR to 1.0 is being ignored.<br>
<br>
Any suggestions would be greatly appreciated!<br>
<br>
Cheers,<br>
Greg.<br>
</blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><span style="background-color: #ead1dc; font-family: monospace, monospace;"><i><span style="color: #000000;">Dr. Ernesto Zurbriggen</span></i></span><div><span style="font-family: monospace, monospace;"><i style="background-color:rgb(234,209,220)"><br></i></span><div><span style="background-color:rgb(234,209,220)"><span style="font-family: monospace, monospace;"><i><span style="color: #444444;">Consejo Nacional de Investigaciones Científicas y Técnicas </span></i></span><i style="font-size:12.8px;font-family:monospace,monospace"><span style="color: #274e13;">(CONICET)</span></i><i style="font-family:monospace,monospace;font-size:12.8px"><span style="color: #444444;">, Instituto de Astronomía Teórica y Experimental </span><span style="color: #274e13;">(IATE)</span><span style="color: #444444;">.</span></i></span></div><div><i style="font-size:12.8px;color:rgb(68,68,68);font-family:monospace,monospace;background-color:rgb(234,209,220)"><br></i></div><div><span style="background-color:rgb(234,209,220)"><i style="font-size:12.8px;color:rgb(68,68,68);font-family:monospace,monospace">Universidad Nacional de Córdoba </i><i style="font-size:12.8px;font-family:monospace,monospace"><span style="color: #274e13;">(UNC)</span></i><i style="font-size:12.8px;color:rgb(68,68,68);font-family:monospace,monospace">, </i><span style="font-size: 12.8px; font-family: monospace, monospace;"><i><span style="color: #444444;">Observatorio Astronómico de Córdoba </span></i></span><i style="font-size:12.8px;font-family:monospace,monospace"><span style="color: #274e13;">(OAC)</span></i><i style="font-size:12.8px;color:rgb(68,68,68);font-family:monospace,monospace">.</i></span></div></div><div><i style="color:rgb(68,68,68);font-family:monospace,monospace;font-size:12.8px;background-color:rgb(234,209,220)"><br></i></div><div><i style="color:rgb(68,68,68);font-family:monospace,monospace;font-size:12.8px;background-color:rgb(234,209,220)">Teléfono: +54 0351 4331064-5, interno 222.</i></div><div><span style="font-size:12.8px"><i><span style="background-color:rgb(234,209,220)"><span style="color: #0000ff;"><u>Laprida 854, Bº Observatorio (CP 5000), Córdoba, Argentina</u></span><span style="color: #444444;">.</span></span><br></i></span><span style="color: #444444;"></span></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><br></div></div></body></html>