Comments by "Tony L" (@tlangdon12) on "Vertical Axis Wind Turbine Aerodynamics and Design" video.

  1. While a mechanical system would be relatively simple, Rosie has neglected to mention the difficulties that VAWTs can have in starting, and also the need for them to cope with high windspeeds, e.g. by feathering the blades. These problems mean that the optimum blade angle is dependent on the windspeed, and a mechanical system would be made much more complex if it had to also factor in the windspeed to its mechanics.
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  2. Being ominidirectional also means that they don't need slip rings to transfer the generated power from the nacelle to the round. Slip rings wear out eventually and need maintenance, but then so do the bearings of a VAWT!
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  3. Vertogen are working on just such a design.
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  4. Winglets on the wingtips would allow VAWT blades to create its own ducted shroud as it rotates.
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  5. Yes, its entirely possible. Vertogen are working on just such a design.
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  6. There is a company in the UK called Vertogen that has a patent on a mechanical pitch control mechanism.
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  7. I would share your concerns. A better arrangement to regulate power in high winds is to set the blade angle for as much anti-rotational torque as you can without stalling the blades (and then zero torque), but if you have no ability to change the pitch you are left with the electrical torque that the generator can produce, and as you observe, if this fails, you will get a runaway. To my mind any turbine needs an emergency brake, so it would be better to plan on implementing them from the outset.
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  8. Anything that can increase the wind speed seen by the turbine in low wind conditions will help, but in high wind, it would be ideal if the funnels could be reversed so that their action helped protect the turbine.
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  9. To get you started, there are a range of options as to how you might vary the pitch of the turbine blades; using a cam, you might turn the blade through less than 180 degrees, or using a gear mounted on the blade spar, you might turn it through the full 360 degrees. The cam or gear might be operated by a mechanical arragement or by a motor operating under the control of a fast acting electronic controller. The interesting bit is the calculation of the apparent wind, lift, drag, resultant lift and torque vectors and then controlling and optimising these to extract the most energy from the wind. Having full control over the blade pitch allows starting to be optimised, and for the turbine to be braked in high winds.
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  10. Very interest comments. Can you explain any more about how the energy in the tip vortices was harvested as thrust for the turbine?
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  11.  @GarretKrampe  Thank you.
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  12. Vertogen have been working on this for a number of years.
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  13. That could work, e.g. installing them in a chimney, but you have to be careful you don't impede the primary function of the chimney which is to allow the poisonous combustion products to be dumped into the fresh air.
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  14. Vertogen are working on just such a system.
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  15. You instantly loose the benefit that the turbine is omnidirectional when it is vertical. It's not when it is turned on its side.
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  16. Vertogen are working on just such a system.
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