[TowerTalk] Error correction: Re: Wind loading

[Jim Lux]

At 08:19 PM 3/26/2006, Jim Lux wrote:
>At 06:17 PM 3/26/2006, Michael Tope wrote:
>
> >
>
>Cd varies as a function of Re, which in turn scales as Windspeed and
>diameter (that is, if the velocity doubles, the Re doubles...if the
>diameter doubles the Re is halved)

This is wrong.. Re is proportional to "length" * "velocity", so the latter 
half of the statement is incorrect..

If diameter doubles, Re doubles...

So, bigger tubes make for bigger Re, pushing you up to the Cd=0.18, which 
is what it convergest to for large Re  (6" tubes in 60 mi/hr winds, etc.)




Jim..