OT: Wind Loading on Antennas - insight from da Vinci

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OT: Wind Loading on Antennas - insight from da Vinci

K6LMP
This is 'way off topic except for Elecrafters who home-brew antennas. I apologize for using the bandwidth.

While antenna home brewers are primarily concerned with electrical performance of various antenna designs, we also must take into consideration the physical strength of the antenna, particularly with respect to wind loading. For example, just how beefy do we need to make the boom on a long Yagi? And what taper schedule optimizes for strength vs. weight?

There's an interesting article posted online about tree growth, at

http://www.wired.com/wiredscience/2011/11/branching-tree-physics/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+wired%2Findex+%28Wired%3A+Index+3+%28Top+Stories+2%29%29&utm_content=Google+Feedfetcher

which tangentially touches upon this question.  The article goes back to an observation by Leonardo da Vinci that tree limbs grow to a certain diameter -- roughly speaking, when a trunk splits into multiple branches, the sum of the diameters of the limbs equals the diameter of the trunk.  Nobody ever figured out why trees grow like this, until now.  A French mathematician has demonstrated that this is due to wind loading on the leaves.   He modeled a tree as cantilevered beams assembled to form a fractal network. Antennas can be considered similarly, I hypothesize.

It would take someone with more math capability than I have (as a former English major) to apply this thinking to antenna design, but I suspect that such analysis would suggest the most efficient taper schedules, for example, in building a Yagi.

OK you engineering types, have at it!

Lew K6LMP
K3 #3805


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