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Old   March 11, 2011, 03:53
Default Wave simulation in CFX
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Hi, I am simulating waves in CFX by specifying an inlet velocity profile obtained from linear wave theory. The waves I make start off nicely but then suffer substantial damping as they move along the grid. I have read some papers and this damping seems to be a common problem, but not to the same extent as in my simulations. Any ideas what this is due to? Is CFX capable of modelling such waves?
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Old   March 11, 2011, 05:42
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Yes, CFX should be capable of modelling waves with little dissipation.

Check your simulation is well converged, your mesh quality is good and you are running second order space and time differencing. For spacial differencing I would use hybrid with a blend factor of 1.0 as that is pure second order with no highly dissipative first order.
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Old   March 16, 2011, 18:46
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I have done all of that but I am still experiencing excessive dissipation. Any other ideas on what i could do?
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Old   March 18, 2011, 07:25
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That's the basics covered, so time to start looking a bit deeper. Lots of things to look at. Here's a few ideas to start you off:
1) single versus double precision
2) free surface sharpening algorithm
3) mesh quality (have you tested on a hex grid with aspect ratio 1?)
4) mesh size
5) time step size
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Old   March 18, 2011, 07:47
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Ok, so I'll have a look at these aspects! Thanks for the advice. I really appreciate it.
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Old   August 21, 2012, 16:59
Default Wave Modeling in Ansys CFX
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Hi
I need to generate wave in ansys cfx, but how can i model it???????
plz Help me
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Old   August 21, 2012, 19:31
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Do the free surface over a bump CFX tutorial.
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Old   September 5, 2012, 12:05
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Quote:
Originally Posted by ghorrocks View Post
Do the free surface over a bump CFX tutorial.
very thank 4 your advise.
i did this example, but i don't know how to simulate wave.
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Old   September 21, 2012, 19:29
Default Tank Modeling
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Hi
I want simulatie a tank that has 1.5 m height and 1m of it cover with water in ansys cfx. How can i do it?
Please Help
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Old   September 24, 2012, 20:39
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You have to adapt the tutorial example to your case. You can describe your wave with a CEL expression or other function. If you do not know how to do this then do more tutorials to learn CEL and other general functions.
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Old   October 3, 2012, 13:37
Default Regarding waves
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I want to models waves in CFX or fluent. Can I get any tutorial file to do this?
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Old   October 3, 2012, 15:57
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Did you guys all just get the same homework assignment?
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Old   October 4, 2012, 05:13
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Quote:
Originally Posted by Niru View Post
I want to models waves in CFX or fluent. Can I get any tutorial file to do this?
I hadn't tutorial file.
but for wave simulation there are two main method:
1- velocity profile (u,w) in inlet
2- Inlet motion
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Old   October 4, 2012, 05:30
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Quote:
Originally Posted by Niru View Post
I want to models waves in CFX or fluent. Can I get any tutorial file to do this?
I hadn't tutorial file.
but for wave simulation there are two main method:
1- velocity profile (u,w) in inlet
2- Inlet motion
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Old   November 29, 2012, 06:50
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Quote:
Originally Posted by sorenasrn View Post
I hadn't tutorial file.
but for wave simulation there are two main method:
1- velocity profile (u,w) in inlet
2- Inlet motion

Dear Sorenasrn !
Could you tell me more about making vWave by applying velocity in inlet,.. i have already tried many time but no result...

Brg
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