lateral loads

[Bryan Kelly]

I am looking at a wind generator for home. There is a related thread here but no viable answer.
related thread: https://www.greenpowertalk.org/showthread.php?t=23687&highlight=lateral+load

I have found multiple manufacturers but none of them specify the lateral loads that will be imposed upon the tower.

Might there be some kind of a general formula. Something on the order: To get 500 watts of power from the wind, the generator must be catching and/or impeding sufficient wind wind to generate a side load of xxx pounds of force.

Yes, there will be differences in efficiency, but it seems like there must be some kind of a minimum.

Thanks for your time.

[Rob Beckers]

Hi Bryan,

I've been thinking a little bit on how to tackle this question. Clearly the output power of the generator is only part of it; it can be standing still, or be very inefficient, and still present a lateral load.

There is probably a way to calculate realistic values based on Betz limit (slowing down 2/3 of the air flowing through), but I've not gotten that far. I'm pretty sure that you can calculate an upper limit though, by assuming the swept area of the turbine to be a flat plate. The drag of a flat plate in air is well-known.

See for example https://www.engineeringtoolbox.com/drag-coefficient-d_627.html

The actual lateral load should be less than this, making a tower design based on the drag of a flat plate safe (though somewhat overkill).

-RoB-