<br><div class="gmail_quote">Hello,<div><br></div><div>This is my first post to this list after being a casual observer for a while. Let me describe my problem. I have a data set that I produced in FLUENT that I am trying to load into a program that I wrote in VTK. As I am sure everyone knows FLUENT is a Computational Fluid Dynamics analysis package. One of the tenets of CFD that I exploit in my program is what is called the no slip condition. That the velocity will be zero at the wall or obstacle. The problem is that when I load my FLUENT data into VTK convert it to point data and then write it as a vtu file and then examine it in ParaView there are no points that have zero velocity, the points are there, there is just nowhere where its zero. But at the same time, if I export the data from FLUENT in ensight format and then read it into VTK or ParaView, it works as expected. Also, if I load the FLUENT data into the EnSight program it also works. Tecplot also works. Both of these programs show the zero velocity condition at the wall. So In summary here is my problem</div>
<div><br></div><div>FLUENT file -> CellDataToPointData -> Examine in VTK = No zero velocity locations (this is done in my main program, the attached is but a sample of what I am trying to do)</div>
<div>FLUENT file -> CellDataToPointData -> write to VTU -> ParaView examination = No zero velocity locations (this is what the attached program does)</div><div><div>
FLUENT -> Point Data formated ensight file -> ParaView examination = zero velocity locations as anticipated</div></div><div>EnSight reading fluent files -> write to ensight file -> Paraview examination = zero velocity locations as anticipated</div>
<div><br></div><div>From what I can tell there is something going on either with the Fluent reader in VTK or the celldatatopointdata that is producing different results and, in my opinion, changing the data.</div>
<div><br></div><div>As a side note, loading the FLUENT files directly into Paraview doesn't really seem to work. I am experiencing the same issue that is described here, </div><div><br></div><div>
<a href="http://www.mail-archive.com/paraview@paraview.org/msg10346.html" target="_blank">http://www.mail-archive.com/paraview@paraview.org/msg10346.html</a></div><div><br></div><div>but this is not just a ParaView problem, when I use thresholding in VTK to find the Zero Velocity boundries it works if I start from a FLUENT exported Ensight file but does not work if I start from a FLUENT file. The difference it seems is using FLUENT's celldatatopointdata or VTK's</div>
<div><br></div><div><a href="http://www.mail-archive.com/paraview@paraview.org/msg10346.html" target="_blank"></a>Now, the reader will have to understand a few things in order to hopefully provide some help.</div><div><br>
</div><div>1. I am doing University research and am not working for a commercial company</div>
<div>2. I am new to VTK and Paraview and CFD in general so go easy on me</div><div>3. There are quite possibly options I could be using in the FLUENT, the FLUENT reader or CellDataToPointData or XMLUnstructuredGridWriter that could solve my problem</div>
<div>4. I am not claiming that VTK is messing up and that I am guiltless, its probably some option I don't understand.</div><div>5. Maybe there is some way to have fluent not do a multiblock dataset?</div><div><br></div>
<div><br></div><div>Here is my test C++ code</div><div><br></div><div><div>#include<vtk/vtkPoints.h></div><div>#include<vtk/vtkPolyData.h></div><div>#include <vtk/vtkPolyDataWriter.h></div><div>#include <vtk/vtkUnstructuredGrid.h></div>
<div>#include <vtk/vtkIdList.h></div><div>#include <vtk/vtkFLUENTReader.h></div><div>#include <vtk/vtkUnstructuredGridWriter.h></div><div>#include <vtk/vtkCellDataToPointData.h></div><div>#include <vtk/vtkXMLUnstructuredGridWriter.h></div>
<div>#include <vtk/vtkMultiBlockDataSet.h></div><div><br></div><div>#include <vector></div><div><br></div><div>using namespace std;</div><div><br></div><div>int main () {</div><div><span style="white-space: pre-wrap;"> </span>cout << "Begin Reading File." << endl;</div>
<div><span style="white-space: pre-wrap;"> </span>vtkFLUENTReader *fluent = vtkFLUENTReader::New();</div><div><span style="white-space: pre-wrap;"> </span>fluent->SetFileName("./oneram6_fine_sep_2.cas");</div>
<div><span style="white-space: pre-wrap;"> </span>fluent->Update();</div><div><br></div><div><span style="white-space: pre-wrap;"> </span>vtkCellDataToPointData *c2p = vtkCellDataToPointData::New();</div>
<div><span style="white-space: pre-wrap;"> </span>c2p->SetInput(fluent->GetOutput()->GetBlock(0));</div><div><span style="white-space: pre-wrap;"> </span>c2p->Update();</div><div>
<br></div><div><span style="white-space: pre-wrap;"> </span>c2p->GetOutput()->Print(cout);</div><div><br></div><div><span style="white-space: pre-wrap;"> </span>vtkXMLUnstructuredGridWriter *xmlwriter = vtkXMLUnstructuredGridWriter::New();</div>
<div><span style="white-space: pre-wrap;"> </span>xmlwriter->SetInput(fluent->GetOutput()->GetBlock(0));</div><div><span style="white-space: pre-wrap;"> </span>xmlwriter->SetFileName("./sep_test.vtu");</div>
<div><span style="white-space: pre-wrap;"> </span>xmlwriter->SetDataModeToBinary();</div><div><span style="white-space: pre-wrap;"> </span>xmlwriter->Write();</div><div><br></div><div>
}</div></div><div><br></div><div>And here are some links to the FLUENT files that I am using, they are pretty giant, 1.5gb in total, but they are hosted at my school so hopefully it will be fast.</div><div><br></div><div>
<a href="http://cafestuff.groups.et.byu.net/oneram6_fine_sep_2.cas" target="_blank">http://cafestuff.groups.et.byu.net/oneram6_fine_sep_2.cas</a></div><div><a href="http://cafestuff.groups.et.byu.net/oneram6_fine_sep_2.dat" target="_blank">http://cafestuff.groups.et.byu.net/oneram6_fine_sep_2.dat</a></div>
<div><br></div><div><br></div><div>I would also be happy to make the EnSight versions of the same files available if that would help.</div><div><br></div><div>Let me know if there is anymore info that I could provide and thank you in advance, hopefully it is just some silly mistake of mine, it would really help my research to get this working.</div>
<div><br></div><font color="#888888"><div>Kevin Hoopes</div><div><a href="mailto:khoopes@byu.edu" target="_blank">khoopes@byu.edu</a></div>
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