Posted by Curbie on December 16, 2009, 12:24 am
Michael,
Interesting video, but how many MW's of electricity are currently
being generated by these devices? As far as this being a "drag type"
device, I see the fins have an airfoil shape, I'd need to see the math
behind that MagLev before pronouncing it a drag type machine. Can you
point me to the math for it or maybe a patent?
Thanks,
Curbie
Posted by Michael B on December 16, 2009, 6:28 am
> Michael,
> Interesting video, but how many MW's of electricity are currently
> being generated by these devices? As far as this being a "drag type"
> device, I see the fins have an airfoil shape, I'd need to see the math
> behind that MagLev before pronouncing it a drag type machine. Can you
> point me to the math for it or maybe a patent?
Oh, I suppose I could probably find a patent laying around if I were
to research it a bit. Just drawing the suggestion that it's a
variation on
the Savonius type rotor from the Enviro Energies website noted at
http://peswiki.com/index.php/Directory:MagLev_Wind_Power_Generator#How_it_W=
orks
Especially the information of its low speed functionality.
The listed website may need to be cut & pasted because of wraparound.
Posted by Curbie on December 16, 2009, 3:59 pm
Micheal,
I read what was linked there, the "How it works" section wasn't very
encouraging for commercial units, and the home-scale units (which is
all I care about) all make good low wind efficiency claims but say
nothing about protecting the units in the occasional gale.
Too many un-answered questions.
Curbie
Posted by Jim Wilkins on December 16, 2009, 2:53 pm
> Michael,
> Interesting video, but how many MW's of electricity are currently
> being generated by these devices? As far as this being a "drag type"
> device, I see the fins have an airfoil shape, I'd need to see the math
> behind that MagLev before pronouncing it a drag type machine. Can you
> point me to the math for it or maybe a patent?
> Thanks,
> Curbie
Other parts of the web site I referenced have a good simple
explanation of lift and drag.
http://www.aviation-history.com/theory/lift.htm
As I understand it drag-type means the airfoil is stalling, flow has
separated from the low-pressure side. The quick visual clue may be an
angle of incidence greater than 15 degrees. For a quick approximation
of 15 degrees extend your arm and make the hitch-hiking fist. That's
also how far the sun travels in an hour.
jsw
Posted by Curbie on December 16, 2009, 4:22 pm
Jim,
If Paul Gipe and Hugh Piggott understand the math, I understand their
explanation; friction losses at high wind speeds are not that much of
a proportional-thief, but in low winds friction losses cam be a
proportional-killer. It is the 20% gain from reduced friction losses
in low winds I was looking for.
Just not enough hard data on this idea yet.
Curbie
> Interesting video, but how many MW's of electricity are currently
> being generated by these devices? As far as this being a "drag type"
> device, I see the fins have an airfoil shape, I'd need to see the math
> behind that MagLev before pronouncing it a drag type machine. Can you
> point me to the math for it or maybe a patent?