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Sorry, I still don't get the problem:<br>
<br>
If you solve the elasticity problem as a single field problem
(solving only for displacement directly) then you don't have stress
or strain in the weak form and also not in the local operator. So,
why is it costly to compute the stress in the driver before passing
to the vtk writer?<br>
<br>
As Felix already pointed out, a mixed approach would directly give
you stress and displacement (you could also include strain) as a
solution vector.<br>
<br>
As Christian E. pointed out the subsampling can help you if your
visualization tool cannot handle higher order/discontinous basis
functions.<br>
<br>
Best,<br>
Nicolas<br>
<br>
<br>
<br>
On 07/20/2011 03:34 PM, Christian Simon wrote:
<blockquote
cite="mid:OF9F10B41D.E6F54095-ONC12578D3.0048F9C0-C12578D3.004A8671@twt-gmbh.de"
type="cite"><font face="Vorgabe Sans
Serif,Verdana,Arial,Helvetica,Sans-Serif" size="2"><font
face="Vorgabe Sans Serif,Verdana,Arial,Helvetica,Sans-Serif"
size="2">Dear Nicolas,<br>
<br>
yes, the deformation is my primary variable. In order to
compute the the deformation, I need to compute the stress (it
is necessary in the residuum). So I have the stress only in
the local operator.<br>
<br>
Thanks in advance,<br>
Christian<br>
<br>
<br>
<br>
<font color="#990099">-----Nicolas Schwenck <a
moz-do-not-send="true" class="moz-txt-link-rfc2396E"
href="mailto:nicolas.schwenck@iws.uni-stuttgart.de"><nicolas.schwenck@iws.uni-stuttgart.de></a>
schrieb: -----</font>
<div>
<blockquote style="border-left: 2px solid black;
padding-right: 0px; padding-left: 5px; margin-left: 5px;
margin-right: 0px;">An: <a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="mailto:dune-pdelab@dune-project.org">dune-pdelab@dune-project.org</a>,
Christian Simon <a moz-do-not-send="true"
class="moz-txt-link-rfc2396E"
href="mailto:christian.simon@twt-gmbh.de"><christian.simon@twt-gmbh.de></a><br>
Von: Nicolas Schwenck <a moz-do-not-send="true"
class="moz-txt-link-rfc2396E"
href="mailto:nicolas.schwenck@iws.uni-stuttgart.de"><nicolas.schwenck@iws.uni-stuttgart.de></a><br>
Datum: 20.07.2011 15:08<br>
Betreff: Re: [dune-pdelab] Visualization of Gauss point
data<br>
<br>
<!--Notes ACF
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">--> On 07/20/2011 02:45 PM, Christian
Simon wrote:
<blockquote
cite="mid:OFEC3D423D.850CBC78-ONC12578D3.00460D76-C12578D3.00460DB2@twt-gmbh.de"
type="cite"><font face="Vorgabe Sans
Serif,Verdana,Arial,Helvetica,Sans-Serif" size="2"><font
face="Vorgabe Sans
Serif,Verdana,Arial,Helvetica,Sans-Serif" size="2"><font
face="Vorgabe Sans
Serif,Verdana,Arial,Helvetica,Sans-Serif" size="2">Dear
all,<br>
<br>
I moved this question from the dune mailing list
to the dune-pdelab mailing list.<br>
<br>
Here is the problem:<br>
I computed stresses at the Gauss points resulting
from the deformation gradients in my local
operator. Now I wonder, how I can visualize these
stresses via vtkwriter directly from the local
operator, which is on element basis, without a
second calculation of the variable in the driver
*_Q2.hh or somewhere else? Or is there a way to
assign these stress values to a vector container
and visualize it in the driver *_Q2.hh?<br>
<br>
Maybe it is possible to extrapolate these values
to the nodes within the operator and assign the
values to a vector container, which in turn can be
visualized by the vtkwriter?<br>
<br>
Is this there a solution for this problem?<br>
</font></font></font><br>
</blockquote>
<br>
Dear Christian,<br>
<br>
Just to clarify: <br>
<br>
Do you have the deformation as primary variable for which
you solve and with this solution you reconstruct the
stress?<br>
<br>
If that is true I don't get why do you have the stress in
the local operator.<br>
<br>
Or do you use a mixed approach, where you solve for the
stress and deformation? But then you still would get the
solution not in the operator but in the driver as a
solution vector.<br>
<br>
Best,<br>
Nicolas<br>
<br>
<font face="Courier New,Courier,Feste Breite" size="2">--
<br>
_____________________________________________________________________<br>
<br>
Dipl.-Ing. Nicolas Schwenck<br>
<br>
IWS, Universität Stuttgart phone: +49 711 685 64736<br>
Pfaffenwaldring 61 fax: +49 711 685 60430<br>
D-70569 Stuttgart<br>
<br>
email: <a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="mailto:nicolas.schwenck@iws.uni-stuttgart.de">nicolas.schwenck@iws.uni-stuttgart.de</a><br>
url: <a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="http://www.hydrosys.uni-stuttgart.de">www.hydrosys.uni-stuttgart.de</a><br>
_____________________________________________________________________<br>
<br>
</font> </blockquote>
</div>
</font></font>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
_____________________________________________________________________
Dipl.-Ing. Nicolas Schwenck
IWS, Universität Stuttgart phone: +49 711 685 64736
Pfaffenwaldring 61 fax: +49 711 685 60430
D-70569 Stuttgart
email: <a class="moz-txt-link-abbreviated" href="mailto:nicolas.schwenck@iws.uni-stuttgart.de">nicolas.schwenck@iws.uni-stuttgart.de</a>
url: <a class="moz-txt-link-abbreviated" href="http://www.hydrosys.uni-stuttgart.de">www.hydrosys.uni-stuttgart.de</a>
_____________________________________________________________________
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