CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Visualization & Post-Processing Software > ParaView

[OpenFOAM] visualise vector field

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree5Likes
  • 1 Post By JR22
  • 4 Post By JR22

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 22, 2013, 11:12
Default visualise vector field
  #1
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
dear all,

i have a 3d domain, i slice it and i want to disply the velocity vector field..

below is what i see..
ie onluy the vector where it enters the domain and thats it..
can an1 help me please?
Attached Images
File Type: jpg off colour.jpg (20.5 KB, 319 views)
zaynah04 is offline   Reply With Quote

Old   March 24, 2013, 13:34
Default
  #2
Retired Super Moderator
 
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,974
Blog Entries: 45
Rep Power: 128
wyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to all
Hi zaynah,

A few questions:
  • Are you certain that you have the correct item selected in the pipeline browser, before using the Glyph filter?
  • Are you certain you have got a slice of the 3D domain? Perhaps you've selected a 2nd slice, which has reduced the 2D slice to a "1D" line.
  • Are you certain you've made the slice along the correct axis?
  • What are the configuration values you've used for the Glyph filter?
Best regards,
Bruno
__________________
wyldckat is offline   Reply With Quote

Old   March 25, 2013, 07:27
Default
  #3
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
Quote:
Originally Posted by wyldckat View Post
Hi zaynah,

A few questions:
  • Are you certain that you have the correct item selected in the pipeline browser, before using the Glyph filter?
  • Are you certain you have got a slice of the 3D domain? Perhaps you've selected a 2nd slice, which has reduced the 2D slice to a "1D" line.
  • Are you certain you've made the slice along the correct axis?
  • What are the configuration values you've used for the Glyph filter?
Best regards,
Bruno
yes i selected the right item in pipeline..
yes i have a slice off the 3d domain..i slice it from muy 3d domain,
yeh i have made the slice along right axis.. sometiems i use x axis sometimes along z axis..

for glyph in properties panel of object inspector i use scale mode off

in display i use U and then magnitude

thnaks alot for taking time to reply
zay
zaynah04 is offline   Reply With Quote

Old   March 25, 2013, 16:25
Default
  #4
Retired Super Moderator
 
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,974
Blog Entries: 45
Rep Power: 128
wyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to all
What about the number of glyphs to be represented?
For reference, the options I was asking about are the ones listed here: http://paraview.org/OnlineHelpCurrent/Glyph.html
__________________
wyldckat is offline   Reply With Quote

Old   March 25, 2013, 23:17
Default
  #5
Senior Member
 
JR22's Avatar
 
Jose Rey
Join Date: Oct 2012
Posts: 134
Rep Power: 17
JR22 will become famous soon enough
Within the Glyph panel, Check the "Scale Mode", try changing it from "vector" to "off". If for some reason you have vectors of large magnitude at the boundary, they will dominate the display (making smaller arrows/2D Glyphs) look much smaller (possibly dots).
zaynah04 likes this.
JR22 is offline   Reply With Quote

Old   March 25, 2013, 23:18
Default
  #6
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
Quote:
Originally Posted by JR22 View Post
Within the Glyph panel, Check the "Scale Mode", try changing it from "vector" to "off". If for some reason you have vectors of large magnitude at the boundary, they will dominate the display (making smaller arrows/2D Glyphs) look much smaller (possibly dots).

yesh this i had done already.
zaynah04 is offline   Reply With Quote

Old   March 25, 2013, 23:52
Default
  #7
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
Quote:
Originally Posted by wyldckat View Post
What about the number of glyphs to be represented?
For reference, the options I was asking about are the ones listed here: http://paraview.org/OnlineHelpCurrent/Glyph.html
Dear Wyldcat

thanks again for taking time and reply to me.

i am sending you 2 screenshots
its same thing one with only the glyph seen and one with bith glyph and slice seen.



ps: scale mode =off
set scale factor=1
max no of points=5000
glyph type=2D glyph, arrow
Attached Images
File Type: jpg zr.jpg (75.5 KB, 227 views)
File Type: jpg 2.jpg (61.4 KB, 187 views)
zaynah04 is offline   Reply With Quote

Old   March 26, 2013, 04:39
Default
  #8
Retired Super Moderator
 
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,974
Blog Entries: 45
Rep Power: 128
wyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to all
Try increasing "max no of points" to 10x more or 100x...

There are a few possible issues that you might be having:
  • Values that are NaN or Inf, which might lead ParaView to have problems.
  • Values could be too small.
  • The glyphs might be showing in the back of the slice.
Any chance you can export the slice to VTK format and then share it here on the forum or Dropbox or similar? It would make it easier to diagnose the problem.
__________________
wyldckat is offline   Reply With Quote

Old   March 26, 2013, 07:21
Default
  #9
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
i convert to VTK format ... what must i do now can you please guide me?

Last edited by zaynah04; March 26, 2013 at 07:52.
zaynah04 is offline   Reply With Quote

Old   March 26, 2013, 07:23
Default
  #10
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
Quote:
Originally Posted by wyldckat View Post
  • Values that are NaN or Inf, which might lead ParaView to have problems.
can you please tell me where i can find NaN or Inf?

also please notice how the entering vector arrow is coloured whereas all remian zero in the domain..

Last edited by zaynah04; March 26, 2013 at 08:21.
zaynah04 is offline   Reply With Quote

Old   March 26, 2013, 10:01
Default
  #11
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
i have used another case, this time a 2D case and used glyph attached is the image..
we can see the glyph and the velocity colours..only the glyph are not coloured..

this is the whole trouble.. why is the arrows not geting coloured?

one case i use the colour by u and i choose x..
as i had sent wind along the x axis. and it was 0.7m/s, hence i saw a constant 0.7m/s over the whole doamain..

but it does nto change around the shape etc..

i think somehting is wrong somewhere..

Last edited by zaynah04; March 26, 2013 at 10:27.
zaynah04 is offline   Reply With Quote

Old   April 1, 2013, 08:06
Default
  #12
Retired Super Moderator
 
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,974
Blog Entries: 45
Rep Power: 128
wyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to allwyldckat is a name known to all
Hi zaynah,

Without the VTK files to look at the results myself, I'm unable to be of much help.

But for some of the questions you had:
  • You can export to VTK file through the menu entry "File -> Save Data", then choose the export format. But keep in mind that you can only export the selected item in the "Pipeline Browser". So:
    1. Select an item in the "Pipeline Browser".
    2. Go to the menu and click on "File -> Save Data".
    3. Choose to export to VTK (legacy) format.
  • To the see the raw values so you can check if there are any Inf or NaN values, use the "Spreadsheet" view: http://www.paraview.org/Wiki/ParaVie...readsheet_View
Best regards,
Bruno
__________________
wyldckat is offline   Reply With Quote

Old   April 1, 2013, 08:22
Default
  #13
Senior Member
 
JR22's Avatar
 
Jose Rey
Join Date: Oct 2012
Posts: 134
Rep Power: 17
JR22 will become famous soon enough
I just saw the last reply to this message and remembered that I've had plenty of instances where Paraview just arbitrarily ate a whole section of Glyphs when putting them in a slice. I wonder if you can:

1. Start from a VTK file, which you obtain by using the command foamToVTK in the terminal. It might work from the direct paraFoam file, but I haven't tested this.
2. Create a Plane from the Source menu,
3. Change the X and Y Resolution of the plane to something like 200x100 (x,y). By default, the resolution is 1x1, which is wrong if you are going to do step 4 below.
4. Use the Resample with Dataset filter (the source is the created plane, and the input is your entire dataset) on your main dataset.
5. Place your Glyph filter on the ResampleWithDataset object (which is your mapped surface). Make sure you place the Glyph filter on the ResampleWithDataset that has the cube icon, and not on the ones with the arrow (if you misplace the Glyph filter, it will not work).
6. Make sure that only the ResampleWithDataset object + the Glyphs are visible, as the plane itself will hide the mapped results.

This should give you an evenly distributed mesh with a matrix of points that should allow the glyph filter to hold on to. Let us know as I haven't done this, but would like to know if it works. This is the process I use to map results to arbitrary surfaces in paraview. I used it in the last thread I started. In it, I create sources, resample (map) results, and then integrate with moreless detrimental results:
http://www.cfd-online.com/Forums/ope...tml#post417557

UPDATE: Ok, I put Glyphs on the mapped surface and it does work. See link above, I may have answered my question on that other thread. Zaynah, can you try this?
wyldckat, fumiya, canopus and 1 others like this.

Last edited by JR22; April 2, 2013 at 16:33. Reason: grammar, Update, Glyph filter placement, start from VTK file
JR22 is offline   Reply With Quote

Old   April 2, 2013, 15:12
Default
  #14
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
hii jose

first of all thank you for this superb answer..

i am trying it right now..

i will get back to you on that

thanks again
zaynah
zaynah04 is offline   Reply With Quote

Old   April 2, 2013, 15:24
Default
  #15
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road






when i do resamble i get this error..



ERROR: In /home/opencfd/OpenFOAM/ThirdParty-2.1.x/ParaView-3.12.0/VTK/Filtering/vtkExecutive.cxx, line 756
vtkPVCompositeDataPipeline (0x9b42a30): Algorithm vtkPProbeFilter(0x162e1620) returned failure for request: vtkInformation (0x16481660)
Debug: Off
Modified Time: 172930
Reference Count: 1
Registered Events: (none)
Request: REQUEST_DATA_OBJECT
FROM_OUTPUT_PORT: 0
ALGORITHM_AFTER_FORWARD: 1
FORWARD_DIRECTION: 0


another thing is how you chnage the resolution of x and y?


zaynah04 is offline   Reply With Quote

Old   April 2, 2013, 16:31
Default
  #16
Senior Member
 
JR22's Avatar
 
Jose Rey
Join Date: Oct 2012
Posts: 134
Rep Power: 17
JR22 will become famous soon enough
One more thing, I started from a VTK file which I exported using foamToVTK. Check the panel for the Plane, there you will find X and Y resolution. Also, the coordinates in this precise plane should give you what you need I think, since you have wind blowing on the structures in the X direction too. Some arrows don't show because they are behind the plane.

Attached Images
File Type: jpg how_to_draw_arrows_on_surface_using_paraview.jpg (58.6 KB, 797 views)

Last edited by JR22; April 2, 2013 at 16:37. Reason: plane source coordinates
JR22 is offline   Reply With Quote

Old   April 4, 2013, 03:49
Default
  #17
Senior Member
 
zaynah K.
Join Date: Jun 2012
Location: Mauritius
Posts: 138
Rep Power: 13
zaynah04 is on a distinguished road
hi

i slice my 3D domain,then i apply glyph on it. then i re sample with data set and I GOT IT...

thanksssssssssss a lot jose
from zay


Last edited by zaynah04; April 4, 2013 at 05:25.
zaynah04 is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Visualise CFX res files salihovic CFX 3 July 16, 2010 08:35
Visualise CFX Mesh Aspect Ratio? Ianto CFX 7 November 13, 2008 04:05
How can I visualise a particle cloud Sandra FLUENT 0 May 23, 2006 05:41
How to visualise Peter Main CFD Forum 3 October 20, 2003 13:02
cfx5 visualise nick CFX 2 October 1, 2001 12:14


All times are GMT -4. The time now is 12:25.