TheBackShed.com

Home	JAQForum Ver 24.01
Log In or Join
Active Topics
Local Time 01:35 15 Jul 2025	Privacy Policy
Jump to

Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.

Forum Index : Windmills : how to figure rotor offset

Author

Message

newbie-from-pa
Newbie

Joined: 20/06/2008
Location: United States
Posts: 8

Posted: 02:28pm 20 Jun 2008

Copy link to clipboard

Print this post

I would like to know how to calculate the rotor offset. From what I read the diameter of the prop/blades changes the rotor offset. Please advise. Thanks.

Gill

Senior Member

Joined: 11/11/2006
Location: Australia
Posts: 669

Posted: 03:58pm 20 Jun 2008

Copy link to clipboard

Print this post

G'day n-f-p,
Welcome to the forum.
Regarding your quirey,
Well no, if you select an offset it doesn't change no matter what blades you fit.
What changes is the moment of force due to the changed blade diameter. A moment of force in American speak has the unit foot/pounds. In our case it is the offset distance(in feet) multiplied by the force(in pounds) exerted by the wind onto the blades.

The purpose of the offset is part of the furling geometry. This furling system is balanced with all sections interdependent. Change one thing and it will need to be compensated for by another. There is no formula to calculate every item of a furling system. One needs to select key parameters and work the others out from them. If a suitable balance of the system is not achieved, some adjustment of the selected parameters is needed. There is more of an art than a science/formula to designing windmills. A good start is to look at successful designs and get a feel for the relationships, then coupled with research into the forces and their causes and effects, build on that.

If however you need guaranteed results then build to somebody else's proven design.

was working fine... til the smoke got out.
Cheers Gill _Cairns, FNQ

Print this page

To reply to this topic, you need to log in.