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VOF Damping

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Old   April 17, 2012, 23:54
Default VOF Damping
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Hi, I am wondering about how to use damping in free surface flow.
I am simulating a towing tank test of a planing type hull of length ~1m
I put my boundary 2L upstream, 6L downstream, 3L on the transverse direction.

I am running calm water condition, and would like to know what is the significant of wave damping, and in Star-CCM+ is there any guidelines on how do we 'select' the appropriate wave damping length?

Thanks
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Old   April 18, 2012, 10:33
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Ryan Coe
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Are you asking about boundary conditions used to damp wave reflections?
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Old   April 18, 2012, 11:11
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No, I am want to know how far should we apply the damping from the field of interest, and also how do we decide the VOF wave damping length

And also does damping is also important if we are running Flat Wave model?
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Old   June 14, 2013, 09:23
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Arun Krishnan.L.H
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Hi,

I also have a question regarding wave damping. Is there a way to increase the damping coefficient? Looks like I have some wave reflection happening. I saw the manual says it damps the w velocity. Should my vertical then be in z direction? My vertical is y axis. Just wanted to make sure.

need guidance if you know
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Arun
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Old   December 1, 2014, 11:57
Default What CD-Adaco says
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Hello all,

I have the same difficulty in selecting the wave damping length for my resistance simulations.

It is said in the Steve Portal Article Number 5216, that "the VofDampingLength to be at least of the order of the ship length". However, the EHP resistance assistant makes this length twice the ship length.

I have never had the opportunity to compare the results by using L or 2L. Does anyone?

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Higuel
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Old   December 1, 2014, 21:16
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Yes, twice the ship length is still in order of the ship length ()
You can try to compare I suggest and see the difference..
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