Gravity slowdown

Continuing the discussion from Low radius loop:

The effect of gravity slowdown or speedup caused by the mass of the wing during loop. The change in power is nominally



m - kite mass
g - gravitational acceleration 9.81 m/s/s pointing down
v - speed vector of kite motion

This is if we assume that speed of the kite does not change during the loop.

Looking at drag mode vs yoyo power production, the effect of force applied as a braking force (going upwards) and the effect of reeling out for yoyo power production is much the same thing.

Accounting for a speed loss during loop, the effect of gravity slowdown has a positive feedback also reducing the kite speed and thus the power generated by the wing.

Gravity speedup is less of a positive speedup compare to slowdown, as increasing the speed will increase drag quite quickly thus making the effect less relevant.

Just to be pedantic and throw in my usual 2 bits… This is the case for single kites not kites being flown as part of a kite ring / rotary kite network

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Yeah, back to 3000 years ago (that we know of - probably far longer) - a rotor - who knew?
By the way, the word is “braking”, not “breaking”.
God I just can’t imagine being so lost in even coming up with a reasonable configuration, then going down the rabbit hole of trying to analyze the fact of being so lost by getting more lost in mathematics.
AWE - a celebration of being lost. A “we are totally-lost-fest” - let’s charge admission and hire a band! And make sure we apply lots of equations!

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I’d argue its relevant for all rotating AWE. Heres why: a windmill balances the weight of the blades using a beam connected to a hub. We cant use the beam for AWE except in smaller scale. Instead we must transfer pull from the part of the rig going downwards to the part going upwards. This transfer of force is not perfect as the bridle is ideally circular but in practice more like a shape with N straight lines (N is the number of kite wings). To accomodate for this, the kites must possibly generate centrifugal forces to keep the bridle stiff. This is a loss.

Though you dont actually have «slowdown» there are some effects that must be taken into account even for such systems.

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