Wind Load on Structure Adjacent to Tanks

[ChadV]

Hi all!

Does anybody have experience or literature related to wind loads on a structure located adjacent to one or multiple large circular tanks?

The situation I'm looking at has a grid of oil storage tanks about 100 feet in diameter and 40 feet high. Centre-to-centre tank spacing is 130 feet, meaning out-to-out distance is 30 feet. The plan is to have a small structure containing some equipment located between two of the tanks (attached sketch). I'm wondering if anyone is aware of provisions or design guidance for wind loads on the equipment structure to account for a "funneling" type of effect as wind is directed through the smaller opening between tanks. I've found some literature related to wind pressures on tanks themselves, but nothing related to adjacent structures.

Logically there have to be some upper and lower bounds for the spacing where this is no longer an issue, and it would be possible to look at some more research-type publications to come up with a rational approach... but before I do that, can anybody suggest approaches, publications, etc? There's always the be-very-conservative route but I'd like to temper that with some printed design guidance if I can find it.

Thanks!

 

[JedClampett]

I hate to be Mr. obvious, but wouldn't this be good case for a wind tunnel analysis? I know you're probably under a tight budget, but maybe it would be worth the money to get it right, rather than deal with the uncertainty.

 

[JStephen]

I'd vote for the "be-very-conservative" approach, myself. Probably cheaper to double the design wind forces than it is to do a wind-tunnel test. Maybe cheaper than spending a day googling for answers, for that matter. I'd say it's a similar situation to rooftop equipment.

For what it's worth, those channeling effects are not normally considered in the design of the tanks themselves, though. Not to say they oughtn't be, but they aren't.

I think you could find literature for flow between cylinders, but it'd be based on a 2-D situation (infinitely long cylinders) as might occur in heat exchanger bank, but your case is distinctly different.

 

[SlideRuleEra]

I second the "very-conservative" approach. The tanks are "short" compared to their diameter. The equipment building is even shorter, probably. Influence of wind "funneling", which is real, is going to be overridden by the boundary layer effects from the ground surface. Wind tunnel studies are great for "tall" structures, where boundary layer is only a small issue, but in this case studies would likely be inconclusive.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[rb1957]

the wake behind these tanks can be very different to just doubling the remote wind. Brute force is one thing, the dynamic effects of the wakes is another.

I'd've thought that it was something that's been done before (building structures near tank farms) so maybe someone's developed an acceptable solution.

another day in paradise, or is paradise one day closer ?

 

[IFRs]

I've seen some wind tunnel tests, I'll try to find them.

I have experienced first hand the wind funneling effect - we always take our breaks where the wind blows and walk around the tank to find the sweet spot. But, I'm not sure the wind was 2x or 3x faster, just there.