CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

Line probe problem

Register Blogs Community New Posts Updated Threads Search

Like Tree2Likes
  • 1 Post By fluid23
  • 1 Post By me3840

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   December 3, 2012, 16:17
Default Line probe problem
  #1
Member
 
anonymous
Join Date: Dec 2012
Posts: 33
Rep Power: 13
badger1 is on a distinguished road
I have put a line probe into a simulation but it does not seem to fill in all the points. it has random spaces where there are not points and the data is then missing when I use that line probe to plot a graph.

Does anyone how how to solve that?

Any help would be greatly appriciated.
badger1 is offline   Reply With Quote

Old   June 12, 2017, 11:31
Default
  #2
Member
 
Join Date: Aug 2014
Location: Germany
Posts: 77
Rep Power: 11
harry123 is on a distinguished road
Anyone can answer the above question please ?
harry123 is offline   Reply With Quote

Old   June 12, 2017, 15:00
Default
  #3
Senior Member
 
Matt
Join Date: Aug 2014
Posts: 947
Rep Power: 17
fluid23 is on a distinguished road
Are you looking at a geometry displayer of your probe points in a scene or their position in an XY plot? If you are looking at the XY plot, any probe point that lies in a cell will show the value of at that cell center. This is true whether you are talking about position, pressure, velocity or whatever. To get a smooth plot that shows the values at your actual probe positions you must enable 'smooth values' in the property window. XY Plot > Y Types > Y Type 1 (or 2, 3, etc...). This turns on node interpolated values.
fluid23 is offline   Reply With Quote

Old   June 12, 2017, 15:02
Default
  #4
Senior Member
 
Matt
Join Date: Aug 2014
Posts: 947
Rep Power: 17
fluid23 is on a distinguished road
Sorry, I should have read closer. Can you show an image of this?
fluid23 is offline   Reply With Quote

Old   June 14, 2017, 06:04
Default
  #5
Member
 
Join Date: Aug 2014
Location: Germany
Posts: 77
Rep Power: 11
harry123 is on a distinguished road
I meant like this, the line probe with points you can see in pic have been defined over the full length, but points turn up only in some areas.
If I plot some quantity on this line, the data is missing where there are no points shown
Attached Images
File Type: png probe.png (117.7 KB, 83 views)
harry123 is offline   Reply With Quote

Old   June 14, 2017, 09:00
Default
  #6
Senior Member
 
Matt
Join Date: Aug 2014
Posts: 947
Rep Power: 17
fluid23 is on a distinguished road
Ah... Is this line probe on a boundary surface (inlet/outlet/etc...)? If that is the case, then some of your points are defined outside of the domain and therefore have no position or scalar data to plot or display. This could be the result of your volume mesh or how you defined the line probe. There are two things you can try that should fix this.

1) Edit the derived part and select the 'snap to part' option then select that face.

OR

2) Move the line probe some tiny distance upstream so that all the points fall within the domain.
harry123 likes this.
fluid23 is offline   Reply With Quote

Old   June 14, 2017, 09:39
Default
  #7
Member
 
Join Date: Aug 2014
Location: Germany
Posts: 77
Rep Power: 11
harry123 is on a distinguished road
Ah yes..!! I got the problem now.

Actually I was using snap to part (to my outlet), but the problem was that the x coordinate for point 2 of the line remains slightly outside boundary , (10^-15m difference !!!). But that was causing the problem.

I got it right now.

Really appreciate your genius, its awesome..!!

Thanks a lot
harry123 is offline   Reply With Quote

Old   June 14, 2017, 09:42
Default
  #8
Senior Member
 
Matt
Join Date: Aug 2014
Posts: 947
Rep Power: 17
fluid23 is on a distinguished road
Not a problem. Glad I could help.
fluid23 is offline   Reply With Quote

Old   June 15, 2017, 14:46
Default
  #9
Senior Member
 
Join Date: Nov 2010
Location: USA
Posts: 1,232
Rep Power: 24
me3840 is on a distinguished road
Just for future reference, except for seeding streamline rakes I avoid using line probes at all costs. Wherever you need a line probe you can easily use a section plane (or a section plane of a section plane) to do the same thing more reliably.
harry123 likes this.
me3840 is offline   Reply With Quote

Old   June 19, 2017, 07:31
Default
  #10
Member
 
Join Date: Aug 2014
Location: Germany
Posts: 77
Rep Power: 11
harry123 is on a distinguished road
Thanks for the advice, will keep that in mind.
harry123 is offline   Reply With Quote

Reply

Tags
line probe


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
[Gmsh] Layers in a curved surface Artex85 OpenFOAM Meshing & Mesh Conversion 1 December 18, 2011 08:51
channelFoam for a 3D pipe AlmostSurelyRob OpenFOAM 3 June 24, 2011 13:06
1.7.x Environment Variables on Linux 10.04 rasma OpenFOAM Installation 9 July 30, 2010 04:43
Install problem in linux navaladi OpenFOAM Installation 11 July 17, 2008 02:24
OpenFOAM with IBM AIX matthias OpenFOAM Installation 20 March 25, 2008 02:36


All times are GMT -4. The time now is 23:28.