Lagrangian particle tracking.

[Norbert Modlinski]

Dear Support and Users.

I have few questions regarding the particle tracking module:

1. Is it possible to run Lagrangian tracking with steady-state algorithm for continuous phase (idtvar = -1)? How does it refer to "isttio" key word?

2. How to visualize the particle tracks in Paraview. In results I obtain: deplacement.CASE and trajectoire.ensight.CASE files in LAGR.... folder. When I open the second file the PV crashes giving the following error:

ERROR: In /home/kitware/Kitware/ParaView-3.8.1/source/Servers/Filters/vtkEnSightReader2.cxx, line 307
vtkEnSightGoldReader2 (0x2536010): error reading geometry file
 
ERROR: In /home/kitware/Kitware/ParaView-3.8.1/source/VTK/Filtering/vtkExecutive.cxx, line 756
vtkCompositeDataPipeline (0x25a0c00): Algorithm vtkEnSightGoldReader2(0x2536010) returned failure for request: vtkInformation (0x26da290)
Debug: Off
Modified Time: 77304
Reference Count: 1
Registered Events: (none)
Request: REQUEST_DATA
FROM_OUTPUT_PORT: 0
FORWARD_DIRECTION: 0
ALGORITHM_AFTER_FORWARD: 1


When I open the first file the data is read without any warning but I cannot obtain any visualization.

Which filter should I use for the  deplacement.CASE file? Do I have to use this file separately or in combination with general result file (CHR.case)?

3. What does the "dtref" mean in case of calculation on frozen velocity field? Is this a integral time step and Lagrangian iteration simply mean integration step? Are the particles injected only in the first Lagrangian iteration?

Look forward to receive your answer.

Best regards
Norbert

[Matthieu Guillaud]

Hello,

these is some answers, which I hope will be helpful.

1) We can't  do calculation with coupling Lagrangian model and fluide
case with idtvar=-1 but what you can do is coupling the Lagrangian
model with a frozen velocity field which was previously calculated with
idtvar=-1.

2) Can you tell me what's the version of Code_Saturne you use?

3) In case of calculation on frozen velocity field "dtref" is the time step of the integration for the Lagrangian.
     You can inject your particles when you want, at the first
iteration, or at any 'n' time step. You can choose that on the GUI or
in the uslag2.f90 file.

Best regards.

Matthieu Guillaud

[Matthieu Guillaud]

Hello M Modlinski,
 
to answer your second question, there is a problem with Code_Saturne. So I attach the patch used to fix the problem.

It contains two files that you have to use.

You can look at the topic :
http://code-saturne.org/forum/viewtopic.php?f=9&t=907

where the problem was talked about.

Regards.

M Guillaud

[Norbert Modlinski]

Hell Matthieu,
 
I use the 2.0.0-rc2 version of CS. I think the patch files are already included in that version. I use 3.8.0 version of ParaView. Shall I switch to 3.9.0? 
When I open the deplacement.CASE file the data is read without any warning but I cannot obtain any visualization. Do I have to use any specific filter in PV?
Thank you
Regards
Norbert

[Matthieu Guillaud]

Hello Norbert,
 
sorry for the delay...
I don't know if you resolved your problem but I know that there is a new version of paraview : 3.10.0-RC1.
You said that you were using Code_Saturne 2.0.0-rc2, now you can download 2.0.1.
Tell me if you still have the problem with the new versions.
 
 
Regards,
Matthieu

[Norbert Modlinski]

Hi Matthieu,
 
I have just compiled the 2.0.1 version of CS and Paraview 3.10.0-RC1. It seems to work now. 
Thank you.
 
Regards
Norbert