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hydrofoil at max speed limit

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ronnie
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Re: hydrofoil at max speed limit

Postby ronnie » Fri Dec 08, 2017 9:07 am


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Re: hydrofoil at max speed limit

Postby Kevin Brooker » Fri Dec 08, 2017 1:38 pm

The L/D goes down as speed goes up. A max of 10 (as in the example) is at best glide. Go faster and the drag goes up as the square of the speed. The formula holds for the foil too. The limit is a lot closer than we realize and is most likely governed by the limit of the rider than equipment.

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Re: hydrofoil at max speed limit

Postby Regis-de-giens » Fri Dec 08, 2017 3:05 pm

The lift also goes square with the speed, so L/D should not vary too much if you stay in the same type of fluid flow. But indeed as I tried to say with the 500 kg effort in the legs example, actual reasonnable speed will be far below.

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Re: hydrofoil at max speed limit

Postby Kevin Brooker » Fri Dec 08, 2017 3:33 pm

The drag created by the non-lift generating parts (lines,rider, anything but the wing) will kill the L/D at a rate greater than the development of pure lift. Generating power will not be the limiting factor. we seem to agree the limit will be the strength of the rider.


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