Towertalk
[Top] [All Lists]

[TowerTalk] ANTENNA SURFACE AREA VS ROTOR

To: <towertalk@contesting.com>
Subject: [TowerTalk] ANTENNA SURFACE AREA VS ROTOR
From: NI6W@yagistress.minden.nv.us (Kurt Andress)
Date: Wed, 17 Jun 1998 07:57:35 -0700
Paul asks
> Kurt,
> 
> Wouldn't the effective area of a 38' boom at 2" diameter be 6.33SqFt.
> and  9.5SqFt. at 3" ?  I assume it is the cross sectional area we are
> concerned with.
> 
> 73s de WA6IBU, Paul

Hi Paul,
Well, without getting into a complicated explanation, it depends on which
set of standards one is using to determine what the  windload will be.
The 6.33 SqFt is the projected area of the boom. I multiplied it by a 2/3
shape factor for round tubing. This would be used with the .004*v^2 formula
for wind pressure to get the wind load.
Another approach would use a shape factor of 1.2 and a different wind
pressure formula to get very close to the same wind load.
I happen to know that KLM used the first one.
73, Kurt

YagiStress - The Ultimate Mechanical Design Software for Yagi's
Visit - http://freeyellow.com/members3/yagistress


--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


<Prev in Thread] Current Thread [Next in Thread>