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Waves and a floating body... in CFX?

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Old   January 10, 2011, 15:21
Default Waves and a floating body... in CFX?
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Hi, I'm relatively new to CFD, so please bear w/ me...

I want to look at the effectiveness of a breakwater on decreasing the sea state in open water, but the breakwater is a floating at the air/water interface due to it's own buoyancy.

Are you able to have a floating body in CFX? The minimal work I've done was where the object is in the flow field (airfoils, etc.).

I've done the 'flow over a bump' tutorial and gotten wave action by varying the speed over the bump, but not sure if this is the most effective way to 'induce' waves. Am I even using the right software (CFX)?

Thanks in advance to any help!
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Old   January 19, 2011, 09:06
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Ansys 13 help > cfx > tutorials > 32. Calculation of the Buoy using CFX Rigid Body Solver..
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Old   January 19, 2011, 12:20
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Thanks, I did that tutorial the other day and looks like what I need, but I am having a hard time creating the model i need and correct expressions for my simulation.

Also, I don't exactly know how to create the right 'sea state' to impose on the object, so looks like I'll have to play w/ how much/fast to move the boundary to create the right sea state... I don't suppose anyone knows how to create the right sea states like this? Any help would be appreciated.

Thanks again.
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Old   January 19, 2011, 17:12
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If you want to make the simulation of ship or other vessel, you should perhaps try Ansys Aqwa. In ansys 13 aqwa is integrated into workbench.
Bad thing -- no tutorials, just the help.

I've downloaded the simulation of the moored ship from ansys ftp server.
I don't deal with ship building industry, I don't understand how this simulation was made.

I can send it to you and you'll have a look. It was made in ansys 13, it's 50 Mb. Need your email.
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Old   January 19, 2011, 17:17
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I tried to use AQWA, but there isn't a tie in w/ workbench at my university (no hydro module), but we do have AQWA available... I asked the IT guys if we have the license for the hydro module for workbench, but no response in over a week.

That said, I'll give it a shot; will send email via pm.
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Old   March 11, 2012, 22:25
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Mohammed Zullah
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Hello,

I have been facing the similar issues of simulating the floating bodies. Recently i got the ANSYS software. Could you please kindly send me the simulation (zullah.m@gmail.com). You help would be highly appreciated.



Quote:
Originally Posted by kristeen View Post
If you want to make the simulation of ship or other vessel, you should perhaps try Ansys Aqwa. In ansys 13 aqwa is integrated into workbench.
Bad thing -- no tutorials, just the help.

I've downloaded the simulation of the moored ship from ansys ftp server.
I don't deal with ship building industry, I don't understand how this simulation was made.

I can send it to you and you'll have a look. It was made in ansys 13, it's 50 Mb. Need your email.
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Old   March 12, 2012, 15:30
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Dear users, thirsty for tutorials,
type in google "ansys tutorials rutracker.org" and choose 1st (now) link.
For 6DOF simulation of ship in waves, take a look at Multiphase in Fluent and CFX.

Yes, my real name is Santa.
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Old   March 15, 2012, 20:22
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Mohammed Zullah
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Can you please send me the download link. i can not seem to find the download links. Its all in foreign language. Sorry for the inconvenience.

Thanking you in advance.

Quote:
Originally Posted by kristeen View Post
Dear users, thirsty for tutorials,
type in google "ansys tutorials rutracker.org" and choose 1st (now) link.
For 6DOF simulation of ship in waves, take a look at Multiphase in Fluent and CFX.

Yes, my real name is Santa.
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Old   March 15, 2012, 21:04
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Mohammed, i've sent you personal email. Either check your mailbox (zullah.m@gmail.com, right?), or tell your spamprotection to calm down. Or email me -- kristeen@list.ru
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Old   March 26, 2012, 07:09
Default Ansys Aqwa water level problem
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Alan Vassallo
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Hi all, Since I am seeing a similar thread... I am using ansys aqwa to model an offshore jacket structure in a stokes 2nd order regular wave in order to obtain the morison drag forces on the structure. The results come out but I dont think they make sense since when I change the still water level, the morison drag forces do not change. What could my problem be?
I am using line bodies with tube cross-section.
Thanks in advance.
Alan
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Old   May 24, 2012, 15:25
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Hi
Let me know your project.
BR
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Old   May 25, 2012, 03:50
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Hi
AQWA uses diffraction theory,so doesn't solve Noveir-Stocks Equation. In the most of FSI sulotion almost sovled N-S Eq. But there is software which are based on Panel theory( BEM )which need a few CPU, by Morison or Diffraction theory. AQWA is too.
it's possible to transfer loads from AQWA to APDL for structural Analysis based on FD or TD. Also AQWA capable to analysis moored, floating, Multibodies in Irregular or regular wave, plus wind and current.
I hope be useful.

BR
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Old   May 25, 2012, 03:58
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try to check your Model>geometry>Part...In follow detail of your geometry, mean Mass and Drag Factor. So for Drag if be 1, you don't have any variates.
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Old   July 19, 2012, 07:54
Default Problem Solved
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Alan Vassallo
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The cause of this problem was confirmed by ansys support engineers. It is a bug in ANSYS AQWA version 13. The wave inertia force is not correctly worked out, in fact it is always zero. Problem is solved by upgrading to ANSYS version 14. What a disgrace!
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Old   September 7, 2012, 01:39
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Quote:
Originally Posted by kristeen View Post
If you want to make the simulation of ship or other vessel, you should perhaps try Ansys Aqwa. In ansys 13 aqwa is integrated into workbench.
Bad thing -- no tutorials, just the help.

I've downloaded the simulation of the moored ship from ansys ftp server.
I don't deal with ship building industry, I don't understand how this simulation was made.

I can send it to you and you'll have a look. It was made in ansys 13, it's 50 Mb. Need your email.
Hi
I must simulate moored ship, would you please send your downloaded simulation?
my email is: sorenasrn@yahoo.com
thanks
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Old   September 7, 2012, 02:50
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I've sent the file.
Anyway, since there is a steady demand for these materials, I post everything I have for AQWA:

moored ship
Introduction course
Training course June 2010
Some other stuff

Enjoy!)

If the links die, let me know -- kristeen@list.ru
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Old   September 7, 2012, 06:24
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so thanks
do you know how to simulate a floating body and wave (airy or stokes) in ansys cfx?
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Old   September 7, 2012, 11:20
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Well, I don't know what "airy or stokes" is, but I have something for you.

Merry cfXmas!
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Old   September 12, 2013, 14:14
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To keep links alive..

AQWA:
part 1: http://www39.zippyshare.com/v/41544336/file.html
part 2: http://www39.zippyshare.com/v/33499294/file.html
part 3: http://www39.zippyshare.com/v/18541590/file.html
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