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Line probe problem

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Old   December 3, 2012, 17:17
Default Line probe problem
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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.
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Old   June 12, 2017, 11:31
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Anyone can answer the above question please ?
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Old   June 12, 2017, 15:00
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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.
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Old   June 12, 2017, 15:02
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Sorry, I should have read closer. Can you show an image of this?
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Old   June 14, 2017, 06:04
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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, 10 views)
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Old   June 14, 2017, 09:00
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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.
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Old   June 14, 2017, 09:39
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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
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Old   June 14, 2017, 09:42
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Not a problem. Glad I could help.
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Old   June 15, 2017, 14:46
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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.
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Old   June 19, 2017, 07:31
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Thanks for the advice, will keep that in mind.
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