The 57aises, (average of internal serration and external serration), wind turbine takes a modified 'floor plan', (visible as the inner set of dim lines in the top figure),

from the model 57 turbine, (posted 10 July, 2010), and the broader plan of the 57es revision #1 propeller/rotor, (posted 16 July, and visible as the outer set in the same figure),

averages them, (the stronger, center set of lines), and develops the average using a turbine's passive, power generating pitch .

In other words : The model 57 had placed serration inside of drafting boundary lines that were based upon, (but wider than, in trailing dimension),

the function used for the smooth-edged model 55 wind turbine, (posted on 8 and 13 May, 2010) ;

The 57es revision #1 placed the serration outside these lines ;

And the 57aises averages these two

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It shares with the 57es, (posted 13 July), a swept back tip, (though of individual tailoring) ;

and with its revision #1 a base which extends to the initiation of serration, making it slimmer near the hub than the 55 .

This latter change gives up some torque, particularly at start-up, but should make it easier to apply a brake for maintenance .

Shown are external surfaces and details for wing one of five

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In use, it is my hope that this turbine will be able to exceed the 2pi barrier, syncing with its tips traveling at about seven and a half times the wind's speed .

In order for this to be possible, a turbine will (i believe) need to manage the wakes its wings, ('blades'), produce ;

which could otherwise interfere with airflow into the turbine region, or return from upwind to impact the wings, possibly causing damage .

The wakes' expected locations, (when the turbine is synced to the wind), are shown by vertical gray lines in the top figure .

The wing's serrations are designed to diffuse the leading and trailing edge wakes,

(making them less likely to accumulate energy over several encounters at the same radius),

and to make the leading edge more efficient at parting and cutting through what non-linear flow it meets

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The airflow should accelerate into the troughs, increasing lift, (and drag), where the wing is locally slim and narrow ; while decreasing it across the flanking, 'tooth' sections .

I hope that this will improve efficiency .

Such acceleration would also raise the probability of transonic flow across the wing(s), (in strong wind) .

I don't think this would damage the turbine ~ if the wings were made of graphite composite and craftsmanship was good ~

but to lower noise, pitch detuning, (turning the wings on their axes to optimize pitch to a lower sync-speed), should be available .

Within subsonic flow, i expect the turbine will be very quiet