Wind generator

Box

An interesting concept but the engineering is not something I'm qualified to comment on.

Just a side note on your model itself.
A quick purge reduces it from more than 8mb to less than 2mb.

slbaumgartner

A couple of things occur to me. Most importantly, as the two rings move to feather the blades won't the distance between the posts mounting the blades change? There doesn't seem to be any mechanism to allow this movement. Maybe pivot on one of the rods and have the other move in a slot?

On a more engineering note, what you have designed is a mechanical negative-feedback governor. As such, it will have a resonant frequency at which the blades alternately increase and then decrease their feathering. With a bit of luck, the mechanism will have enough friction to damp out this oscillation, but it is something to be wary of as an inadequately damped resonance will build up until it destroys the mechanism!

Steve

Futurepast

@slbaumgartner said:

A couple of things occur to me. Most importantly, as the two rings move to feather the blades won't the distance between the posts mounting the blades change? There doesn't seem to be any mechanism to allow this movement. Maybe pivot on one of the rods and have the other move in a slot?

On a more engineering note, what you have designed is a mechanical negative-feedback governor. As such, it will have a resonant frequency at which the blades alternately increase and then decrease their feathering. With a bit of luck, the mechanism will have enough friction to damp out this oscillation, but it is something to be wary of as an inadequately damped resonance will build up until it destroys the mechanism!

Steve

The four tabs holding the rings together have bearings (to control alignment)and springs (to allow the rings to spread apart as the veins rotate). I was hoping that the tension of the return spring and the pressure of the four ring springs would dampen any vibration, but that was what I was HOPEING lol. This is a proto type. I don't know of anything like it to try and copy!

jolran

@unknownuser said:

But neither he nor I could come up with a clutch to slow the blades down in high winds

Don't know if possible, but another approach could be changing the angles of the blades in the wind direction ? Like an umbrella ? That could ease the force of the wind.
Sort of lika a PAX fan closing. Could be problematic if winds changes irradically.
http://www.pax.se/en/product/accessories-fans/passad-backdraught-shutter

Anton_S

@jolran said:

@unknownuser said:

But neither he nor I could come up with a clutch to slow the blades down in high winds

Don't know if possible, but another approach could be changing the angles of the blades in the wind direction ? Like an umbrella ? That could ease the force of the wind.
Sort of lika a PAX fan closing. Could be problematic if winds changes irradically.
http://www.pax.se/en/product/accessories-fans/passad-backdraught-shutter

I though it would just unrotate the blades so the wind doesn't has much surface area to act on. But it looks like these 2 masses at centre were made for different purpose

jolran

Yeah, probably. But I thought the question was how to slow down the RPM in strong winds..

Anyway, if the station is rotatable/hinged, when folded the blades would act as parachute directing the station in wrong direction, perhaps..

Anton_S

@jolran said:

Yeah, probably. But I thought the question was how to slow down the RPM in strong winds..

Won't rotating the blades so their face normal is perpendicular to the wind reduce the rpm? Or at least prevent the wind from increasing the rpm?
That's what I was talking about if you didn't comprehend me

Futurepast

@anton_s said:

@jolran said:

Yeah, probably. But I thought the question was how to slow down the RPM in strong winds..

Won't rotating the blades so their face normal is perpendicular to the wind reduce the rpm? Or at least prevent the wind from increasing the rpm?
That's what I was talking about if you didn't comprehend me

That is what I was looking for Constant RPM. It's easier to rate the torque power at a set RPM. And control the current flow from a DC generator. Besides at higher RPMs the down wind side of the blade causes air turbulence to the next blade which causes more buffeting. (At least so I have read) lol

jolran

@unknownuser said:

That's what I was talking about if you didn't comprehend me

Looks like I did not. My bad.

I know nothing about the subject, in particular..

Mike Amos

I thought the most efficient form of windmill was the Turkish variant. It is inside and the building has vertical slats which can be adjusted to increase or decrease the amount of wind applied to the sails, they also rotate around a vertical rather than horizontal axes.