Wind turbine update

[kww]

In the 10-15mph winds here yesterday I was watching and waiting for something interresting to happen, other than a few wimpy spins from the hardest gusts, but that's all I got.  Today however we had 15-20, maybe even a few gusts of 25mph wind, which I still can't get over how it transformed my turbine from something totally unimpressive to something that scared me a little. 8-l  Several times today the blade went into a blur and made a low quiet hissing sound, rpms went much higher than the day before with the slight increase in windspeed.  I guess it shows how a little faster moving rotor can capture a significantly larger amount of wind energy.  Really seems to explain how freeing up a little extra motion can have a big advantage as well as with the larger diam. rotor where tip speed is higher for the same rpm.  I'm a little undecided now as what to do with this first turbine after seeing it crank up, so I guess I'll just build number two. :-)  I think I'd like the bigger rotor to be further out in the field in case we have "liftoff". LOL

Kevin

[iFred]

HE HE... Like that uh! Yep, it's a thrill like no other.. you built it and now it works.. Pretty Cool! Pretty impressive what a little wind can really do. Just lay under it on a nice day when it's turning nice and watch. Pretty cool.

Get some pic's if you can!

ifred.

 

[Norm]

   Speaking of pic of windmills...that's a problem for me...digital camera has too fast of a shutter speed it catches the blades at a standstill have to borrow my daughters older model digital with slower shutter speed to get a pic of windmills with blurred blades...ah well problems, problems! Eh? (:>) Norm.  

[kww]

I don't know about laying under it when it's spinning fast, I think I'll wait till it's gone through some higher winds first and see if it holds together. LOL  I really can't imagine it holding together in 25+mph winds considering how it was running yesterday.  My furling system is totally untested and I have no idea if it'll furl in time.  The wind's thrust on the rotor has to lift the whole alternator/blade/etc. for 100% furling and that'll be around 70 lbs of thrust I'm guessing.  I saw no furling yesterday and trying to picture this thing in winds strong enough to make in furl makes me want to run for cover. LOL  I may have some very interresting pictures in the near future. :-)  I'll try to get one with the thing about half furled, I think that'd be a cool picture.

Kevin

[wooferhound]

Is it making power yet, or just spinnin' ?

[kww]

I ran in the house when I saw it spinning fast and my heater was glowing.  I cut on two more of the heat lamps(4 total) and they glowed well too, only saw around a 1 volt drop for each lamp I cut on.  The max. voltage I saw was 25vac so there wasn't a lot of current being used by the 110vac heat lamps at that point.  I'm going to have to make some custom wire element heaters to get all the power out of my turbine because 50vac is all it'll make due to the rpm limit of the rotor.  Maybe I'll just add 10 or so more heat lamps. ;-)  The next turbine I make will make 110vac max., I hope, but use a 10 foot rotor so it'll make a lot more volts/rpm.  I feel the 10 foot rotor is needed to overcome the bearing and hystoresis drags and to reach a good rpm for making some power in around 10mph winds.  After that I think I'll try a smaller(8 footer?)dual magnet disk machine.

[bruce1]

     Speaking of fast spinning props, I had a 8' rotor on a tripod, 12' tower for awhile just messing with it. It had no motor connected, no load at all. One night I was watching it spin in the breeze(so cool when something you made with your own hands actually works), when the wind started coming up. I kept watching it, standing real close to it, as the wind kept increasing. Pretty soon the tower was tweaking, and the prop was sounding exactly like a turbo prop airplane pulling away from a terminal gate, it scared the crap out of me. I got further and further away from it as the storm front moved through and the wind speeds got higher and higher. I had the tripod anchored down with steel posts at the time, and slowly the tripod kept leaning backwards and started pulling the posts out of the ground. I wanted to run up there and try holding the tower into place, at the same wondering just how far into my skull one of those blades could penetrate if it flew apart. I stood there and watched her go down, but I sure learned alot about how much force the wind can have. LOTS!!

                                         Good Luck, Bruce

[kww]

Sounds like quite an experience.  Yeah, turbo prop airplane is a good description when these things get going, really took me by surprize, my first time seeing a modern wind turbine in action.  After seeing this I'm really starting to understand why DanB likes the idea of a big slow turning rotor which turns out of the wind rather early.  I think I'll be heading in that direction myself in general.  However, I may make some tiny fast ones to put out in the yard to run lights, pump water, etc. and just to experiment with.  Anyway, this stuff is a lot of fun in several ways and pays you back for your investment, my kind of thing. :-)

Kevin