# Q criterion in Paraview
**URL:** https://discourse.paraview.org/t/q-criterion-in-paraview/5062
**Category:** ParaView Support
**Tags:** vtk
**Created:** [August 9, 2020, 8:15am UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062 "2020-08-09T08:15:08Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@monika13](https://discourse.paraview.org/u/monika13)
#### Post date: [August 9, 2020, 8:15am UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/1 "2020-08-09T08:15:09Z")
Hello,
i am trying to open this LES data file for around 3GB vtu but Paraview keep crashing and does not open. I am just wondering is this problem of Paraview or my system.
Also I am trying to evaluate Qcriterion if this file can able to open. Please advise how can I do it? Because online I see all but i do find contour to show Q criterion anywhere.
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [August 10, 2020, 8:28am UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/2 "2020-08-10T08:28:23Z")
Please share your file
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### Author:  [@monika13](https://discourse.paraview.org/u/monika13)
#### Post date: [August 12, 2020, 5:03pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/3 "2020-08-12T17:03:02Z")
Uploading: Injection\_13325.vtu…
I think I tried multiple times but file here is not uploading and giving error. Is there any other way I can share it?
I am trying to get hair pin structures in my surfaces with Q criterion .
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [August 27, 2020, 2:47pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/4 "2020-08-27T14:47:10Z")
Use a website like wetransfer or google drive.
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### Author:  [@monika13](https://discourse.paraview.org/u/monika13)
#### Post date: [August 27, 2020, 7:09pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/5 "2020-08-27T19:09:12Z")
Sure. Here is my Paraview file for which I am trying to get this hairpin vortices as attached. I already have SU2 extracted Q criterion for me .
[https://drive.google.com/drive/folders/1ho83NblhE6AV0UtTgtVkUz4P3KTK\_r9k?usp=sharing](https://drive.google.com/drive/folders/1ho83NblhE6AV0UtTgtVkUz4P3KTK_r9k?usp=sharing)
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [August 31, 2020, 9:55am UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/6 "2020-08-31T09:55:30Z")
I was able to open your file with ParaView 5.8.1 on linux, but it was using up to 25G of memory to be able to do so.
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### Author:  [@monika13](https://discourse.paraview.org/u/monika13)
#### Post date: [August 31, 2020, 2:04pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/7 "2020-08-31T14:04:58Z")
Hello,
Sure then it’s just memory problem in my system. But can we able to do Q criterion (iso-surfaces) for velocity magnitude in this memory constraint?
Monika ChauhanSent from my iPhone
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [August 31, 2020, 2:30pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/8 "2020-08-31T14:30:53Z")
Yes it should be possible, but in any case, I’d suggest to ressample to an image first in order to be able to use GPU side computation for the ise surfaces.
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### Author:  [@monika13](https://discourse.paraview.org/u/monika13)
#### Post date: [August 31, 2020, 2:59pm UTC](https://discourse.paraview.org/t/q-criterion-in-paraview/5062/9 "2020-08-31T14:59:53Z")
Ok Great! I will try it. Thank you!