Why VAWT technology doesn't advance ?

[Mary B]

Guy nearish me took an old combine, put it on top of a giant bearing from something, gutted it so from the head to the rear it was hollow. Cut the rear out and where the head would be he added a horizontal VAWT rotor, if memory serves me he used cut in half 55 gallon barrels welded together... the body acted like vanes to keep it aimed... it worked for awhile... I think he used really cheap bearings and they seized after about 10 years... it is still perched up on that hill the last time I was in that area!

[Bruce S]

The air needing to escape was the reason the "S" types Mother Earth News always overlapped theirs and had the center open. This kept the air from getting "stuck" .

Bruce S

[Adriaan Kragten]

" When the kinetic energy changes, the air slows down, but still has to LEAVE if any more air is going to get IN to replace it.  So you can't slow it down too much."
that is the problem i discovered when working on 3 bladed drag mills. the air gets trapped and looses its energy . it has to be pushed out of the way in order for energetic air to take its place.
 i found  a squirrel cage design that did that.

The aerodynamic behaviour of a squirrel cage rotor is about the same as that of a Savonius rotor. There is a part of a revolution for which there is a flow through the rotor and for this part the rotor is working as a lift machine if the tip speed ratio is high enough. But if you would draw the speed diagram for 12 positions of the blade, like I did in KD 601 for the H-Darrieus rotor and in KD 417 for the rotating blade design, you will see that there is a large part of a revolution for which the angle of attack at the leading edge of the blade is completely wrong and this causes a lot of aerodynamic drag eating up most of the power produced by that part of a revolution for which the torque is positive.

A squirrel cage rotor is normally used as a ventilator but then the air enters axially at the centre of the rotor and leaves radially at the outer circumference. This kind of flow pattern gives a rather efficient transformation of mechanical power into aerodynamic power. For a wind turbine you should have the opposite direction of the flow but that isn't possible as for a wind turbine the flow enters radially and leaves radially.

[electrondady1]

i have a squirrel cage ventilator on my green house and as you say the air inters in one direction and leaves at 90 degrees to that flow. the vanes have an angle and when they are rotated they create  low pressure in the cavity the vanes form .
i don't imagine  you get a great deal of snow in Holland but i noticed that after a blizzard, the snow at the base of every tree has been  scoured by the wind and forms a hollow around  most of its circumference.
the energy in that area must be elevated
 so
that is were i want to harvest  wind energy.
there is a phenomenon in nature, (i can't recall the name )  that air moving past a cylinder can create a  rotation  in the cylinder.
that is also of interest to me.
as i said the proto types were very promising.

[joestue]

i don't imagine  you get a great deal of snow in Holland but i noticed that after a blizzard, the snow at the base of every tree has been  scoured by the wind and forms a hollow around  most of its circumference.

The missing snow is on the tree

[electrondady1]

thanks for sorting that out for me Joe . My interest is not in where the snow went . My interest lies in the force that removed it .