DIY Vertical Axis Wind Turbine

The only problem with the helical blade vertical axis windcharger systems are that they don't make any near overall power of more conventional airfoil lift(propeller) systems. It's basic mechanics really, the longer the lever, the greater the amount of work it can produce. A 2-3 meter prop blade can create almost 1k ft/lbs of torque at speed. Kindo of makes you wonder why railways systems don't have windchargers sitting right next to them. It wouldn't take much engineering genius to create a series curcuit induction acceleration system that could push a train without that would be much safer than current high voltage systems and cheaper than diesel in the long run.

reply to post by crgintx


whist a VAWT wont produce as much torque as the 'traditional' horizontal aerofoil prop turbine, it does have several distinct advantages...

The heaviest component, the gen-set, is housed in the base of the VAWT unit giving stability in high winds and enables easy maintainance access if at ground level

The helical blades, when rotating at speed will act in principle as a self-stabiliser through the upwardly-drawn circular flow of air across the blades, and are not dependant on needing to be facing into the wind to turn, as it's shape allows a turbulent or uni-directional airflow to rotate the structure, making it better suited to ground/low-level mounting

Prop-blade turbines must be very accurately balanced to even-out any stresses as the blade-tips will be travelling at 300-400+ mph at average operational winspeeds, making them suceptible to stress-failure at too high wind speeds

...here's what happens when things go wrong with prop-turbines



edit: you can see a white transit van parked at the base of the tower to give a scale comparison of size...the generator-pod is as big the van itself!

[edit on 14-6-2008 by citizen smith]

Any further news on this c smith?
WAs following your experiment with interest tbh, looked like it had some promise

reply to post by babylonstew


Apologies to all for not posting any project updates recently...my workshop-time has been limited due to work, but there will be more photos and scanned sketchbook plans coming very soon tho!

reply to post by citizen smith


Thank you for the Update!

We all seem to have these nasty things called JOBS that severely interfere with our ATS time!

Not only that, you have taken on an extremely involved project, and we cannot expect immediate results.

It usually takes 3 tries to get it right, so no worries and Thank You for the Brain Food!

Also remember that 'mistakes' are ONLY "teachers", and we take the lesson and move on without worrying about the "Learning Curve".

Best Regards,

Blitzkreigen

reply to post by Blitzkreigen


thx for the encouragement



keep your eyes peeled for a new update!

Have you made any more progress?

reply to post by citizen smith



citizen, that is one hell of a project you got on your hands. Awesome. As some one who despises (yes, despises) workshop time, I got to say, your projects made me go all 'dammit thats cool, wish i didn't despise workshops'...

rofl. Keep us updated dude.

reply to post by citizen smith


The Utube video was amazing! I am going to work on a similar design for my use. One point I wanted to make, I am sure you noticed, the Utube design allowed for air to flow BETWEEN the blades from the "pushed" blade into the "trailing" blade. This gives extra push and will become more evident as the wind speed picks up. Your design seems to have eliminated this feature, is this correct? I may have misconstrued your pictorials.

Curt

Don't know how far you've gotten on your project but it would have been a lot easier to build a wire frame and cover it with something. And you could have cut down drastically on the weight which would have made it more efficient. Plus it would have been easier to adjust for balance.

I was talking this over with a relative of mine and he reckons to get the balance done you can try this when fabricating the helix using aluminum:


Clamp one end of your aluminium blade into a vice or suchlike so that the blade is horizontal.
Then using a device to grip the metal piece from the other end and a strong pair of arms you can aim to twist the metal so there is a complete turn like this.

Key: --- metal
ooo helix turn

Before:

Vice ---------------------------------------------------------
--------------------------------------------------------- You
---------------------------------------------------------

After:

Vice ooooooooooooo-----------------------------------
-----------------ooooooooooooo----------------- You
----------------------------------oooooooooooooo

Repeat this twice for your other two blades to make up your 'wind catchers'
Use this and a metal shaft along with the best wielder you can afford to mig wield it on.
This blade fixing will be crucial if you are to get the balance right too.
Don't know how well this would work in practice though...

Well, better late than never...here's the update on the project as promised

These are the last two images of 'Mk I' taken before a rather unfortunate incident..





At this point, the cardboard blade-unit had been thoroughly covered in varnish to waterproof, then a layer of clay applied to take out the 'steps' of the profile to give a smooth surface...this stage went as well as expected, with the clay adhering well and left to dry til 'leather-hard'...there were only very fine hairline cracks in the surface of the clay and could now be worked-on with pottery scrapers to give a final almost glass-smooth surface to the touch...

This is the point where it all went horribly wrong...

To test the casting process of the blade surface before getting really mucky with fibreglass and resin, I applied a layer of clingfilm over the outside surface that was to be cast and used ModRoc (plaster-of-paris impregnated gauze bandage) to see how the final shape would look in fibreglass.

As it was a gloroiusly sunny and humid day, I left the whole thing sitting out in the sun to dry for a few hours whilst I went for a walk, and as I was out on my wander a torrential summer-thunderstorm broke. By the time I got back, the whole thing was a sorry looking pile of sodden cardboard and clay
and fit for nothing but the bin

'Annoyed' doesn't even begin to describe how I felt...and the OED now have plenty of newly-invented swear-words for their dictionary

Not to be defeated though, I've refined the design, and will be using the dual neodymium magnet-rotor alternator assembly from Hugh Piggott's HAWT turbine design rather than drill-motors, and a wire-meshed rotor-blade design

thanks to all posters for their input too...watch this space!

HI there, any new updates?

How long it will take to recharge a car battery using a cordless drill motor?
I want to experiment too

Oh Brother where art thou!

What a fcking disaster mate!
Why oh why did you leave it exposed, like a child in front of the wrecking ball!

Nevermind mate, at least your cracking on and rising up like the phoenix as opposed to diving/dying like the dodo.

Did you take a picture of the sloppy mess for us all to stare aghast in horror at?

I'm brewing up a project for my xbow soon so don't worry, we're all in some way or form getting stuff ready mate.

Originally posted by WatchRider
Oh Brother where art thou!

What a fcking disaster mate!
Why oh why did you leave it exposed, like a child in front of the wrecking ball!

Nevermind mate, at least your cracking on and rising up like the phoenix as opposed to diving/dying like the dodo.

Did you take a picture of the sloppy mess for us all to stare aghast in horror at?

Amen brother!

My 'Scoriag-wind turbine reciepe book' has landed, the Neo-magnets have just been ordered, and me dad warned of an imminent take-over of his workshop...there'll be plenty of sparks flying with the MkII build, but that'll only be from the arc-welder and angle-grinder

I was too damn upset and angry at the sight of the sodden mess to do anything other than kick the crap out of the resulting mess left around the yard and curse my own stupidity...lesson learnt!

www.energytower.se...

This looks like an interesting 'spin' on an idea.

Wind is filtered into an ever decreasing diameter inner surface which creates a mini 'tornado' pressure drop..which spins an internal rotor.

It means that the 'generator' side of things can be kept low on the ground too.

Having taken a look at it,it seems to use a wing effect also on the inner rotor.
This is what I was trying to put into words for a 'wing profile' based turbine.

DOH!!!
OK now link is fixed..

[edit on 26-9-2008 by AGENT_T]

I am fascinated by your turbine experiments, probably because I do consultancy work for E-on renewables helping them build Wind Farms, I think we have much to discuss.

NR

BTW The self destructing Danish Turbine took 18 hours to get itself into that mess, the blades we use now can stand 3 x the amount of centifugal motive the old ones did. I am putting up some turbines soon that stand 125 meters high, 3 in Barnsley, 10 in Sedgefield with 10 more planned for the A1. You would have enjoyed watching the one at Nissan sunderland turning itself into a flaming torch

[edit on 27-9-2008 by Northern Raider]

i`m in the middle of building a full size helical using the generator i cabbaged off of a friend the gas motor seized on it . it came with 1-200v out let,4-120 v outlets and 1-12 v outlet. it will be about 15 feet tall, the center shaft and the blades weigh in at about 28 lbs .tot. ,as i used 1.5 inch hollow stainless steel tubing which was rescued from the dumpster.rather than use metal bearings which have a tendency to fall apart i used and incredible slippery plastic which cost me 8 dollars for the 2 pieces i needed for the upper and lower end of the shaft ,it took me 5 minutes at work to turn them to size on the lathe,and to drill them out.
i`m lucky as my property up north has both wind and water power on it, as it has a creek has a 15 foot high water fall on it also. once it`s done and running ill post it back here for you.one thing mentioned later in this forum is that there is not enough speed generated on this system but if you think on it a figure skater spins faster the closer and tighter his limbs are to his body. meaning a belt and pully system or gear system configured properly shoud work ,if not all you need is to generate enough power to run 1 -110 volt motor at 3600 rpm which will run the generator -p.s. get some extra brushes for the motors and generaters cost about 15 to 30 dollars per pair .

citizen Dave i was wondering if we changed the blade style to that of a childs toy. four blades on a stick seems to turn at a very high rate of speed with only our breath ,maybe a change of styles might help us all out.

I saw one recently at an off grid event made in a similar manner, the only difference was they used an 18 volt motor off a bosch regulated down to 13.4 volts DC to be able to recharge automotive batteries, apparently 12 volt vehicle batteries are chargesd at that slightly higher figure. the top and bottom were two S shaped pieces giving a fourway configuration and they were connected by vetical running blades made from pieces of venetian blinds bonded togther to give the strength needed.
FYI the japanese have just built a 3 story one using rare earth magnets , its supposed to be really neat.