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To: newzjunkey

regarding that Superdome, earlier there was discussion of the variance of the winds destructiveness with windspeed. I noted that the power was cubed with speed. I may have been confused, but I rechecked a wind power seb source and found this:
"An important equation used to find the wind power density, how much power is available per square meter is the equation
P = .5 pu³

, where P is the wind power density in W/m2, p is the density of the air, and u³ is the cube of the wind velocity.

An equation for the power available is :
(kinetic energy flux) = .5 p V(3) A---(that is V cubed).

, where p is the kinetic energy density J/m³, V is the velocity of the wind, A is the cross sectional area of the wind on the turbine."

It seems to me, the energy of the wind is related to the cube of the velocity. I would naturally assume that the destructiveness will be related directly to that kinetic energy.


1,226 posted on 08/28/2005 10:36:28 PM PDT by SolomoninSouthDakota (Daschle is gone.)
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To: SolomoninSouthDakota

Power is proportional to velocity cubed.

Drag is proportional to velocity squared.

141 mph is twice as big a wind load as 100 mph.


1,249 posted on 08/28/2005 10:41:25 PM PDT by John Jamieson (Hybrids are a highway around CAFE, that's all they're good for.)
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To: SolomoninSouthDakota
It's aluminum siding on that roof. I don't have a lot of confidence in that technology in a storm where a piece of straw can be shot into a tree. It won't just be wind flowing but a debris field too.

WWL interviewing a FEMA? official. Official says 26,000 at the Super Dome.

1,252 posted on 08/28/2005 10:42:09 PM PDT by newzjunkey (Cindy Sheehan: "All You Are Saying Is Give APPEASEMENT A Chance!")
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To: SolomoninSouthDakota
The abilty to provoke destruction is a -force- question, not a -power- question.

Agreed, once started, the power (force times distance) question comes into play. But the force of my half-ton ass on the couch provides -no- power until the couch is broken. Meanwhile, I am dead weight, and (only) if enough weight, I break the couch.

1,266 posted on 08/28/2005 10:44:47 PM PDT by Cboldt
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To: SolomoninSouthDakota
THe units don't work out in those eqs. you got from that site. WInd E is proporitonal to v2.

Imagine a 1cm3 block moving at 1cm/sec through stationary air. In 1sec it moves 1cm3 of air out of the way. Effectively it moves it 1cm sideways.

The energy of that mass of air being moved is 1/2mv. The power is E/t=E/(1sec).

Since E=F*d, where d-distance:
F=E/d = m/2*v2/1cm

That means the force on 1cm2, or any area is proportional to v2

Just as the E is.

1,375 posted on 08/28/2005 11:01:43 PM PDT by spunkets
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