Author Topic: Prototype Oil Drum wind turbine  (Read 7696 times)

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Bruce S

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Re: Prototype Oil Drum wind turbine
« Reply #27 on: January 04, 2017, 12:55:21 PM »
ULR:
I wonder , at what size S rotor it becomes a better idea to use Carbon Fibre rather than building them using plywood or CDX board?
As hardy as Carbon Fibre is becoming (taylor035 used it for the challenge) I'm thinking it's gotta be getting price comparable.

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Bruce S
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Ungrounded Lightning Rod

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Re: Prototype Oil Drum wind turbine
« Reply #28 on: January 04, 2017, 08:52:36 PM »
ULR:
I wonder , at what size S rotor it becomes a better idea to use Carbon Fibre rather than building them using plywood or CDX board?
As hardy as Carbon Fibre is becoming (taylor035 used it for the challenge) I'm thinking it's gotta be getting price comparable.

I have no clue.  B-)

MattM

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Re: Prototype Oil Drum wind turbine
« Reply #29 on: January 05, 2017, 05:46:01 AM »
Probably much handier and simpler to take vinyl, PVC, or FRC wall panels and shape them with a heat gun.  Much cheaper material.  Lightweight.  Easy to duplicate.

Bruce S

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Re: Prototype Oil Drum wind turbine
« Reply #30 on: January 05, 2017, 07:09:52 AM »
I've seen some pretty cool stuff made with heat shaped PVC, but I'd be worried about people inhaling those fumes.
Would be interesting to give some of those a try tho.
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taylorp035

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Re: Prototype Oil Drum wind turbine
« Reply #31 on: January 29, 2017, 07:30:19 PM »
Carbon fiber would start to get expensive once you are talking about large areas.  My past experience shows it costs about $1000 for 5 m^2 worth of carbon and glue that is in the ball park of 1/16" of an inch thick.  It would be very durable and strong, as well as very light weight, but I think the force from the wind is the bigger issue.  Some UV-light coating would be a good idea to protect the glue.   The cost could probably be lower if you purchased cheaper carbon fiber that isn't as pretty... my latest intake manifold for my project car used this cheaper carbon that worked well for building thickness and handling 15 psi vacuum. 

Making a female mold and making a few blades would be fun.  Maybe make it about 6-8 ft tall and maybe 4 feet wide for each blade.  Do ~2 layers of the 0.021 or 0.030" thick carbon fabric and then add a spar some where in the middle or two of them to increase the rigidity.

The only savonius I've made looked like an Adirondack chair and had ~16" tall and 10" wide blades (3 of them).  It was good for about 100 rpm.... not very good, but it was pretty.  Maybe 2 blades would of been better?

https://www.youtube.com/watch?v=U1HnJ9rynGU




Bruce S

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Re: Prototype Oil Drum wind turbine
« Reply #32 on: January 30, 2017, 09:26:16 AM »
taylor035;
Actually back when Ed from Windstuffknow was doing tons of testing, I think he and other found the 3-bladed to be the better ones.
Certainly slightly harder to build than even my little Tin Coffee can VAWTs but not that much harder if you're building from scratch.

His LENZ VAWTs are based on the 3-bladed design.

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Adriaan Kragten

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Re: Prototype Oil Drum wind turbine
« Reply #33 on: January 30, 2017, 09:31:02 AM »
If you make a big Savonius rotor, it may run nicely at moderate wind speeds. But sometimes very high wind speeds up to 35 m/s may occur (in The Netherlands) and then the rotational speed can become really high. As the whole mass is very large, a certain imbalance is easily obtained and this imbalance will cause severe vibrations at extreme high wind speeds. If the frequency of this vibration reaches the natural frequency of the tower or the guy wires, the problems are even bigger and the whole windmill can be shaken loose from its foundation.