Centrifugally Stiffened Rotor (CSR) as a model for an AWES?

There is a description page 9. If this architecture is used as a model for an AWES, the centifugal force would be relatively low when it scales up. Disruptive Innovation

IMHO the major feature is the tether-blade alignment allowing to minimize the cantilever effect that is encountered on current prototypes of tethered aircrafts with turbines aloft. If an AWES configuration is possible and works, this feature could be a key for scaling.

There are still more informations (see metrics page 17) on

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With wind force the CSR is shaped like a cone and perhaps the aerodynamic forces on the blades don’t tend to expand the rotor (?). But it is not sure: a deeper analysis is required.

So a rotor with a bridle and undergoing… cantilever effect, looks to remain a possibility.

There are similarities to the systems discussed in this thread:

Especially having a stiff lever in the center which is turned by pulling from a kite.
In contrast to a propeller, a yoyo system like kiteswarms wouldn’t actually need the lever. It’s only needed if one wants to transfer a moment to the hub.

Hi @rschmehl ,

As you evoke Mark D. Moore on List of organizations , I opened a topic on Centrifugally Stiffened Rotor (CSR) as a model for an AWES? .

Indeed his purpose was “to put the entire structure in tension”. That can eliminate the cantilever effect of wing, and saving mass.

The CSR (blades + tethers in alignment) becomes a cone shaped due to the wind forces and I am not sure the aerodynamic forces on the blades will expand the rotor as a wing undergoing cantilever effect will do.

I would like to know your advice for this. Thanks.

In Moore’s CSR each blade is aligned with its tether.

Don’t think so. Might look like this, but to transmit moment from hub to blades, levers have to be ahead and behind to transmit moment from blades to hub. Might only be slightly. Else there is no force component on the lever tether connection point tangential to the circle in which is moves.

In the initial CSR the thrust is provided by the propellers that are settled in the end on the tips of blades. So here the hub doesn’t transmit any moment as it can be stationary as well as rotating (see page12: Central Hub Payload) with the CSR.

The centrifugal force allows to align tethers and their respective blades, saving mass.

Please read also the page 14 about bending moments of current wings compared to CSR.

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The problem occurs when the CSR works as an AWES, undergoing wind force. I don’t know if it is still possible to align blade and tether, using aerodynamic force instead of centrifugal force as it scales. If yes it can be a possible winner.