Blade Rotation Direction

[danlenox]

I am curious about if it is advantageous to have the blades rotate clockwise or counter-clockwise.

Perhaps it depends on which hemisphere - or not at all.

I bring this up as I am getting ready to build a 17' turbine and have noticed pictures showing the blade manufactureing in both directions!

[RP]

No it doesn't make any difference except:

One effect to keep in mind is the gyroscopic forces on the blades during a yaw motion when the wind changes direction.  This will tend to make the blades flex since the entire rotor will want to tilt up or down depending on the axle direction and the yaw motion.

Most folks here set up their systems so that during a "hard" yaw when the tail is against the stop, the blades tend to tilt "up" which makes the blades at the bottom of rotation move away from the tower rather than toward it.

[Seaspray0]

I have seen that discussed before.  The simple test to know which way to make your blade spin was to take the front wheel of a bycicle and spin it while holding onto the shaft.  Turn toward the direction your generator will furl and the wheel will either want to turn up or turn down.  If it turns down, then make your blades spin the other way.  During a hard furl, your blades will want to pull away from the tower shaft.

[Flux]

Yes and it is backwards compared with the way most machines are built. Most throw the blade tips towards the tower in a hard furl.

It is very much a second order effect and on a turbulent site the yaw into furl may not be the worst case.

Doesn't really matter, make sure there is sufficient clearance between the blades and tower and forget it.

Flux

[jmk]

 Does furling left or right have any effect with the rotation of the blades? Plus the offset?