Many thanks all for continuing to pursue this in an open forum. Please
keep it up. I am starting to get a little bit of a grip on things.
Also am scheduling a free day to get over to the library at NC State
with my calculator, etc. The quotations of source books will be very
useful.
A question below in quoted text.
Again, thanks, & 73,
Guy
k2av@qsl.net
On Mon, 24 Aug 1998 7:30 -0800, "Hank Lonberg"
<Hank.Lonberg@harrisgrp.com> wrote:
>
>
>
>Bill:
>
>The equation used in TIA/EIA 222-F which is the latest revision and the UBC
>defines the basic wind speed stagnation pressure (a datum) value as:
>
> Qs = 0.00256V*V
>
> This is base on Bernoulli's equation which can be arrainged to give
>
> Qs=1/2*RHOair*V*V8
>
> Density(air) at 59 deg F and 29.92 in Hg is 0.0765 lbs/cf
> Rho=Density/g
> RHOair=.0765/32.2
>
> To express in MPH
>
> Qs= 1/2(.0765/32.2)(1/3600)*(1/3600)(5280/1)*(5280/1)*V*V
>
> Qs= 0.00256*V*V
As temperature goes up the load would decrease. Hurricanes tend to be
70-75 degree events, very warm. Tornados and Thunderstorm microbursts
seem to be very cool, 45 degrees or 50?
Another event common enough, 30-40 mph with rain, 50-60 degrees.
Also in other parts, 30-40 mph with temps below freezing, say 20
degrees F.
What kind of variations would these place in the final figure. What
would be the worst value of these?
>
>
>I don't know of any safety factor in this derivation
>
>Hope this helps
>
>73
>
>Hank / KR7X
>
Guy L. Olinger
k2av@qsl.net
Apex, NC, USA
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