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How to patch initial disturbance on free surface

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Old   November 26, 2008, 08:17
Default How to patch initial disturbance on free surface
  #1
Ted Chu
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Hi all,

I would like to know how to patch a wave profile on the free surface as an initial condition. It is a 2D case. VOF is used. Air and water. The wave will go from left to right.

Thanks...

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Old   November 26, 2008, 08:24
Default Re: How to patch initial disturbance on free surfa
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k.baker
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is it a stratified flow case?
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Old   November 26, 2008, 10:38
Default Re: How to patch initial disturbance on free surfa
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shoushibo
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you can use DEFINE_INIT macro. by judging the relationship between the y coordinate of the cell and the wave profile you can patch the vof is one
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Old   November 26, 2008, 12:21
Default Re: How to patch initial disturbance on free surfa
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Ted Chu
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I guess it is a stratified flow case. Air is on the top, and water is on the bottom. Both are fluids. But, correct me if I am wrong..
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Old   November 26, 2008, 12:33
Default Re: How to patch initial disturbance on free surfa
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Ted Chu
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Thanks shoushibo. By the way, do you have a cas file and the DEFINE_INIT udf which you had patched an initial free surface profile?? I am doing a term project for a class, so kind of in a hurry. Many thanks to you in advance....
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Old   November 26, 2008, 13:57
Default Re: How to patch initial disturbance on free surfa
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k.baker
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is it a pipe flow? you work currently with 2D or 3D? what you want to predict in addition to free surface fluctuations?
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Old   November 26, 2008, 14:04
Default Re: How to patch initial disturbance on free surfa
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BOHIS
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Hi there, I think that Mr. Baker knows me very well. Let me say hello to him! By the way, if you tend to have smooth initial interface, you should put command (rpsetvar 'patch/vof? #t) in TUI before initialization.

good luck
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Old   November 26, 2008, 14:13
Default Re: How to patch initial disturbance on free surfa
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k.baker
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Hey Bohis thanks a lot for your reply with this please tell us in which option in TUI this facility to getting smooth free surface was available?

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Old   November 26, 2008, 22:32
Default Re: How to patch initial disturbance on free surfa
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Ted Chu
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Thank you guys for sharing tips. To answer Mr. Baker's question, I am doing a solitary wave propagation simulation. It is a 2D case. The wave will travel from left to right. The free surface fluctuation will be the only focus. I know how to patch undisturbed free surface into the domain, but don't know how to patch the initial wave profile. shoushibo suggested using DEFINE_INIT. I am trying it now. Do you guys do it differently??

At the mean time, I am moving the left boundary as a wavemaker. But, as we know, it is hard to produce a pure solitary wave this way. The tailing waves always exist.
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Old   November 27, 2008, 10:31
Default Re: How to patch initial disturbance on free surfa
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bohis
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Hi guys, actually I do not know how (rpsetvar 'patch/vof? #t) really works. rpsetvar is scheme command which sets the variable patch/vof. If you use #t, then the interface will be smooth. If you use #f, it will be sharp. You should type it directly as a command in TUI before first initialization.No more questions about it, I do not know more (note: I have never tried it with udf initialization - DEFINE_INIT) As regards patching, you can either create register using adaption panel or if the shape is complicated, then use UDF.

good luck

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Old   November 27, 2008, 10:47
Default Re: How to patch initial disturbance on free surfa
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shoushibo
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if you need a case about define_init macro ,i can provide,please leave a email.
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Old   November 27, 2008, 11:17
Default Re: How to patch initial disturbance on free surfa
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Ted Chu
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Thanks shoushibo. I'd really appreciate it. My email address is yutechu@hotmail.com.

Thanks bohis for your input.
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