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How to remove spurious oscillations for shear stress?

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Old   January 11, 2021, 20:29
Default How to remove spurious oscillations for shear stress?
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Using RANS model for backstep and all is good except the anisotropic component of the shear stress where there is a lot of oscillation at the region of flow separation. I can't remove them even at high mesh density. Any recommendation to remove them?
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Old   January 12, 2021, 17:11
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Hello,

I am not sure if mesh density is the issue here.

To reduce spurious oscillations, damping factors can be implemented mainly in implicit time integration schemes. The bulk viscosity method (BVM) is an explicit scheme for damping spurious oscillation, used in commercial types of software such as LS-DYNA and ABAQUS.

Here is a link to a paper (it's open access) with more information: https://www.sciencedirect.com/scienc...98122115003089
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Old   January 13, 2021, 03:47
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Quote:
Originally Posted by aero_head View Post
Hello,

I am not sure if mesh density is the issue here.

To reduce spurious oscillations, damping factors can be implemented mainly in implicit time integration schemes. The bulk viscosity method (BVM) is an explicit scheme for damping spurious oscillation, used in commercial types of software such as LS-DYNA and ABAQUS.

Here is a link to a paper (it's open access) with more information: https://www.sciencedirect.com/scienc...98122115003089
How do I implement those on Fluent? I can't find those method you mentioned
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