Checks for wind induced vibration on vertical vessel with platforms 2

[IJR]

Dear Pals

We have a 200ft vertical pressure vessel with a roughly mean diameter of 9ft at the base 5ft towards the top

But at least 4 platforms are attached to this vessel, roughly at 50f spacing vertically

Would you rely on roughness of the platforms against vortex induced vibrations?

respects
IJR

 

[JoeTank]

The presence of caged ladders and platforms has often be considered sufficient to minimize the risk of wind induced vibration due to vortex shedding. It's a longstanding position of vessel designers. But, I am not aware of any technical justification or published papers that demonstate that fact. Experience seems to bear out that ladders and platform work.

Steve Braune
Tank Industry Consultants

http://www.tankindustry.com

 

[codeeng]

It's our standard to check for vortex shedding all vessels >10d high regardless of attachments. This is a very simple exercise with the computer design programs available today. We use "Evaluation of Percent Critical Damping of Process Towers" by Karamchandani, Gupta, and Pattbiraman which can be downloaded from:

http://www.codeware.com/papers.html

 

[jte]

IJR-

50' platform spacing? That's a long climb in between platforms! What country will this vessel be installed in?

jt

 

[unclesyd]

Not in the US for sure.
I sure hope the ladders are caged and not like a smoke stack.
This column is awfully skinny too. It must have some anchoring system to handle any wind loads.