Learning Forum

[pegah.mehrabian]

I am trying to simulate the vortex-induced vibration of a cylinder by using ANSYS CFX and Transient Structural. The cylinder is free to move in one direction. The problem is the tube response gets increased by increasing the flow velocity. Which is contrary to real physics. I am wondering if ANSYS is not able to simulate resonance or if I am missing something.

[C N]

Hello Pegah,

I recommend you to check the boundary conditions and I have attached the fsi coupled - transient structural and cfx best practice video link . Kindly follow that on how they have defined the interfaces and boundary conditions in fluid analysis you have to supress the solid part and correctly define the regions.

(7) Analyzing FSI with CFX and Mechanical - Part II - YouTube

(7) Analyzing FSI with CFX and Mechanical - Part I - YouTube

I hope this helps you.

Thanks,

Chaitanya Natraj

 

[pegah.mehrabian]

Hi Chaitanya,

Thank you for your comment and the recommended videos. I am not new to FSI simulations. but recently I've started to simulate the vortex-induced vibration of a cylinder that is free to move in 1D. I wondered why the ANSYS 2-way coupling system couldn't recognize between two branches of lock-in (generally known as resonance). I was interested to hear others' experiences with this physic. Generally, I knew that ANSYS has problems giving the right physics in the VIV problem because of the mass-damping parameter!