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Positive or negative values of Lambda2 for vortex structure visualization?

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Old   May 8, 2017, 09:10
Default Positive or negative values of Lambda2 for vortex structure visualization?
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vidyadhar
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I want to visualize the vortex structures in the flow through a pipe junction having square cross-section.

If I select negative value of Lambda-2 criterion in paraview, I find structures near the walls. For positive values of Lambda2, the structures are away from the walls.

Also,
I am getting same pattern of vortex structures with positive values of Lambda2 which I do get with positive value of Q criterion.

So,
1) should I select positive values of Lambda2 or negative values?
2)Do Q- and Lambda2- criteria give similar structures?


Thanks in advance!!!
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Old   November 26, 2019, 23:12
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Jianrui Zeng
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I am still interested in this topic. Can anyone describe more details about Q- or lambda-2 criterium. Can I just use postProcess -func Lamdba2 to calculate it and visualized it through paraview ?
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Old   November 27, 2019, 00:45
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Quote:
Originally Posted by calf.Z View Post
I am still interested in this topic. Can anyone describe more details about Q- or lambda-2 criterium. Can I just use postProcess -func Lamdba2 to calculate it and visualized it through paraview ?

Hello Zeng,


You may find other suitable answers also.
Any way you may please look at

1.https://www.researchgate.net/post/Po...confined_flows


2. https://www.researchgate.net/post/Ho...n_Ansys_Fluent
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Last edited by vidyadhar; November 27, 2019 at 04:06.
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Old   November 27, 2019, 08:03
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Quote:
Originally Posted by vidyadhar View Post
Hello Zeng,


You may find other suitable answers also.
Any way you may please look at

1.https://www.researchgate.net/post/Po...confined_flows


2. https://www.researchgate.net/post/Ho...n_Ansys_Fluent
Thank you for the valuable information!
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