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-   -   Waves and a floating body... in CFX? (http://www.cfd-online.com/Forums/ansys/83759-waves-floating-body-cfx.html)

salvooch January 10, 2011 16:21

Waves and a floating body... in CFX?
 
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!

kristeen January 19, 2011 10:06

Ansys 13 help > cfx > tutorials > 32. Calculation of the Buoy using CFX Rigid Body Solver..

salvooch January 19, 2011 13:20

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.

kristeen January 19, 2011 18:12

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.

salvooch January 19, 2011 18:17

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.

zullah March 11, 2012 22:25

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 (Post 291213)
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.


kristeen March 12, 2012 15:30

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.

zullah March 15, 2012 20:22

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 (Post 349008)
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.


kristeen March 15, 2012 21:04

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

Digijtal March 26, 2012 07:09

Ansys Aqwa water level problem
 
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

khabiran May 24, 2012 15:25

Hi
Let me know your project.
BR

khabiran May 25, 2012 03:50

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

khabiran May 25, 2012 03:58

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.

Digijtal July 19, 2012 07:54

Problem Solved
 
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!

sorenasrn September 7, 2012 01:39

Quote:

Originally Posted by kristeen (Post 291213)
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

kristeen September 7, 2012 02:50

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

sorenasrn September 7, 2012 06:24

so thanks
do you know how to simulate a floating body and wave (airy or stokes) in ansys cfx?

kristeen September 7, 2012 11:20

Well, I don't know what "airy or stokes" is, but I have something for you.

Merry cfXmas!

kristeen September 12, 2013 14:14

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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