13 January, 2011 .

56aises humpback, wind turbine .

Wing one of five, with detail views of tip ; external surface .

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This model is adapted from the 67aises humpback wind turbine, (posted 26 August 2010),

to be a five winged design intended to sync with the wind when its tips are traveling at just under 2pi times the wind's speed .

The principal change ~ apart from one fewer, and shorter, wings ~ is its proportionally broader teeth .

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As i currently understand or imagine,

some of the operational noise created by wind turbines results from the recombination of air behind the wings .

I think that this and related designs in this series have the potential to be quieter ---

as the wings' sectional geometry relies far more on the Bernoulli principle than on the Newtonian to produce lift .

[ For the Newtonian, it seems likely that at low velocities without substantial chaotic flow,

its trailing downwash will produce a low-frequency pulse of sound .

At higher velocities, if chaotic recombination of the downwash and the air passing under the wing occurs,

there could also be a form of white noise . ]

The sectional profile of this model should produce relatively little trailing downwash once away from the hub ;

and it is my further hope that its serrated trailing edge will diffuse what air-release noise is created .

As always, and as i am amateur, testing the viability of these ideas would be best .

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Unlike many previous posts, surfaces are shown here fully opaque .

Also, the perspective of end-on views has been heightened .

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The gray arcs in the two figures directly above indicate where crossing ripple-effects from other wings are expected to be centered .

It is my belief that these are also a source of operational noise and wear in horizontal axis designs .

The outermost arc, at 2pi, would be from the previous rotation of the same wing ~ if it was that long .