[ariza]

hai guys.
I was a student last semester. I am currently working on final project with the topic of large-diameter cylinder viv in force due to currents and wave forces. I'm using a flow-3d for the simulation of vortex shedding. but until now I can not how.

whether there are any of you guys can help me? provide solutions or suggestions how?

thanks for the help.

[hans_ina]

Originally Posted by ariza

hai guys.
I was a student last semester. I am currently working on final project with the topic of large-diameter cylinder viv in force due to currents and wave forces. I'm using a flow-3d for the simulation of vortex shedding. but until now I can not how.

whether there are any of you guys can help me? provide solutions or suggestions how?

thanks for the help.

Hi Ariza,

what you mean of VIV is vibration due current around cylinder?
can you specified your question about? its your problem on modelling or meshing or else? please specified.

Thanks,
Hans

[ariza]

In my Case,
VIV occurs because the combination of currents and waves.
then, how steps to make simulation with Flow3D?
such as modelling, input, solution, output...

thx for your attention...

[hans_ina]

For modeling, you can input the parameter (read manual handbook) then fill the BC with inlet and outlet as outflow.

Put the parameter and fill current and wave value (note: use free surface for input wave value)

hope this helpfull for your thesis.

[ariza]

Originally Posted by hans_ina

For modeling, you can input the parameter (read manual handbook) then fill the BC with inlet and outlet as outflow.

Put the parameter and fill current and wave value (note: use free surface for input wave value)

hope this helpfull for your thesis.

thx a lot..
now i've finished my final exam..
23 september is my graduation..

[hossein2357]

Originally Posted by hans_ina

For modeling, you can input the parameter (read manual handbook) then fill the BC with inlet and outlet as outflow.

Put the parameter and fill current and wave value (note: use free surface for input wave value)

hope this helpfull for your thesis.

******
hi, i dont underestand"read manual handbook"
which handbook?

[hossein2357]

i simulated cylindric in sea. but i dont know, how i can obtain "vortex" .


'vortex induce vibrating'

[hans_ina]

Originally Posted by hossein2357

******
hi, i dont underestand"read manual handbook"
which handbook?

Originally Posted by hossein2357

i simulated cylindric in sea. but i dont know, how i can obtain "vortex" .


'vortex induce vibrating'

Hi,

You can find it on help menu guy.

[mali]

Hi All,

I think for simulating vortex induced vibration of a bluff body (exm: circular) can be done using the similar case of wingMotion in the tutorial. I had simulated a circular cylinder using pimpleDyMFoam, and it worked for small reduced velocity u* < 1, but it blowed up at higher reduced velocity. I suspected this happened because the system was in resonance, so the vibration was very high in amplitude, where I can saw the mesh changed badly at that time.

If you have suggestion on how I can simulate the VIV problem for high reduced velocity, please let me know.

Cheers
-mali-

[hans_ina]

Originally Posted by mali

Hi All,

I think for simulating vortex induced vibration of a bluff body (exm: circular) can be done using the similar case of wingMotion in the tutorial. I had simulated a circular cylinder using pimpleDyMFoam, and it worked for small reduced velocity u* < 1, but it blowed up at higher reduced velocity. I suspected this happened because the system was in resonance, so the vibration was very high in amplitude, where I can saw the mesh changed badly at that time.

If you have suggestion on how I can simulate the VIV problem for high reduced velocity, please let me know.

Cheers
-mali-

what case you study?

[mali]

Hi hans_ina,

Thanks for your replay.

I used 2D rigid circular cylinder attached with a vertical spring. Re based on diameter of the cylinder was in the range of 3000 to 22000, depending on the value of reduced velocity. For the elastic system, the mass ratio was 2.4 and the damping ratio is 0.0054 , similar to the case of Khalak and Williamson [1996].

Cheers,

[hossein2357]

Hi friend
do you know, how can add damper for Cylinder in viv research or other work.
we want simulate moving object with damper, but we dont know how we can add damper to object.

[mikkysaik]

Hi all. I am trying to model 3D flow around a cylinder using ANSYS fluent. I need info on how to generate a 3D mesh. I tried generating the geometry but got stuck. please I need info on how to go about it.

[jjason]

Originally Posted by ariza

hai guys.
I was a student last semester. I am currently working on final project with the topic of large-diameter cylinder viv in force due to currents and wave forces. I'm using a flow-3d for the simulation of vortex shedding. but until now I can not how.

whether there are any of you guys can help me? provide solutions or suggestions how?

thanks for the help.

Hi Ariza
Could you please tell me that how to combine the wave and current by using flow3d?
Thanks very much,
JJason

[jason_sjtu]

Originally Posted by ariza

hai guys.
I was a student last semester. I am currently working on final project with the topic of large-diameter cylinder viv in force due to currents and wave forces. I'm using a flow-3d for the simulation of vortex shedding. but until now I can not how.

whether there are any of you guys can help me? provide solutions or suggestions how?

thanks for the help.

Hi, I did get the vortex behind a cylinder. My Ur=1~7, or something. it's too long to remember.

my parameters are U_infinite=1, R=1, rho_fluid=1, mu and the spring coefficient are calculated from a few equations.

More importantly, the density and the spring coefficient are the most important.
the simulating time may be 100~700 second, varying according to Ur.

[Erfan785]

Originally Posted by mali

Hi hans_ina,

Thanks for your replay.

I used 2D rigid circular cylinder attached with a vertical spring. Re based on diameter of the cylinder was in the range of 3000 to 22000, depending on the value of reduced velocity. For the elastic system, the mass ratio was 2.4 and the damping ratio is 0.0054 , similar to the case of Khalak and Williamson [1996].

Cheers,

Hi,
can you send me a tutorial about how to simulate this case, please?