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Author Topic: hey guys ! a new type of windmill (french site)  (Read 40547 times)

Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #30 on: December 18, 2007, 02:03:08 PM »
@mine

Interested in your new design and would like to see a diagram.

I assume at this point you don't have any performance data although you mentioned
doing simulations that may give me some guide.

How are you controlling the foil position to get the right attack angle?

ERS

minesapint

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Re: hey guys ! a new type of windmill (french site)
« Reply #31 on: December 18, 2007, 02:55:57 PM »
Foils are controller by worm geared dc motors. At the end of each boom.
Each shaft is encoded.
Wind direction is known using a weather vane or I did toy with the idea of using ultrasonics.
PWM drivers speed up or slow down the blades at certain points.
Blades switch tact at points A and B.
The whole thing rotates slowly, low noise (no tip speed noise as such), can be geared or use multipole genny.
Is also probably a lot less noisy (clutter wise) to radar, less curvey bits for multiple reflections.


Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #32 on: December 19, 2007, 12:34:45 AM »
@mine,

Thanks for the diagram. You said in an earlier post that your aim is to position the foil
at 20deg angle to create lift perpendicular to wind direction.

I believe the aim should be to create lift tangential to the circular path in order to impart
maximum torque.

The principle is the same but our switch points would be different.

Have I interpreted your diagram correctly?

ERS

EDIT: How did you do your simulations? Did you write some code or use something already available?
« Last Edit: December 19, 2007, 01:01:19 AM by Evil Roy Slade »

minesapint

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Re: hey guys ! a new type of windmill (french site)
« Reply #33 on: December 19, 2007, 10:26:44 AM »
lift tangental to circular path......
Possibly although to do this you need to increase the angle of attack to greater than the stalll angle.
All of this is controllable in software - once I have a working prototype I would tweak it for maximum output. The sims I ran assumed pependicular thrust. I was not able to take into account the wake of the preceeding blade - the maths got too complex - its all navir stokes type fluid dynamics stuff....
The main problems are accelerating the blades at point A nad B such that it changes tact. You need a very light blade and powerful motor.
I have asked companies to make parts of the turbine for me and getting a blade strong enough and light enough seems to be the sticking point - no one could really do it within budget.
I guess now as I have come clean with the design its 'open source', I would love to get this thing made as I said I have done the control parts, just need the mechanics.
 

Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #34 on: December 19, 2007, 11:02:15 AM »
Yes I see what you mean about the stall problem.
The tweaking would involve getting the best foil position to maximise the lift vector in the
tangent direction without going into stall state.

It's great that you have shared your idea.

I know you are developing a prototype. I would also like to have a go
at a small scale static prototype. By static I mean to fix the wind direction using a fan.
Its not ideal but ok to do some experimenting. I would then use one symetric foil in fixed position
attached to a sensitive strain gauge to measure its lift in the direction I want it.

From here one could then develop the foil settings matrix to be used by the controlling software.
I know you have probably already done it but this step will give me some evidence that the system
will work as expected.

If at this point I consider it a reasonable chance at success then a full scale proto will be built. Hopefully at this point you could jump in with your expertise.

Finally, although you said your idea is effectively now open source I still consider it yours. Hence I would like your permission to build the small scale prototype.

ERS

ERS



 


Paul-R

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Re: hey guys ! a new type of windmill (french site)
« Reply #35 on: December 19, 2007, 04:30:56 PM »
I patented something similar a few years ago....GB2396190A
Think big. If you can get the device up to 35,000 feet the wind is often at 250 mph
and always above 75mph (the jet stream). It could be tethered and be held up
by kiting. (Permissions will be needed. Civil Aviation will be told  where the lines are).

I wonder if you could get a small sum, maybe ?100,000 or so for a technology
demonstrator from Eon, Ecotricity or similar.
Paul.

Earl

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hey guys ! a new type of windmill (french site)
« Reply #36 on: December 19, 2007, 11:08:01 PM »
@Mine

just saw this link and have not had the time to read it, but it sounds rebel like.

What is your analysis of this idea?

http://peswiki.com/index.php/Directory:Neo-AeroDynamic

Earl

Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #37 on: December 19, 2007, 11:31:10 PM »
@paul

There are a number of companies trying to harness the jet stream. Check out http://www.skywindpower.com/ww/index.htm

@earl
Thanks for the link. Another great idea!

ERS

minesapint

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Re: hey guys ! a new type of windmill (french site)
« Reply #38 on: December 20, 2007, 11:42:17 AM »
ERS

Yep go for it. Tis better to be a small part of something big than to be a large part of nothing at all (current situation).
I have done these tests - I have 3 one metre blades with a 20mm radius semicircle and the front that tails off.
They work up to 25 degrees ish of attack.
If you hold them up in a light breeze you can feel the lift.
I played around with light woods initially and did all sort of measurements but settled onto polystyrene for the next big blade as you can get it cut to any shape quite cheaply.
Do the measurement - tell me how you get on, I will be able to provide the control electronics. You'll also need some hefty motors if you proceed further.

Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #39 on: December 20, 2007, 12:34:44 PM »
@mine

Thanks, I will certainly let you know how things go. Unfortunately (or fortunately),  it's christmas summer holidays here starting from next Monday so all my bodies will be away till Jan 14th.  Until then this project will remain in the theory and concept phase.  I am looking forward to working on this project with you.

Did you check out Earl's link a few posts back? Any comment?

ERS

minesapint

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Re: hey guys ! a new type of windmill (french site)
« Reply #40 on: December 20, 2007, 12:50:35 PM »
Saw the post from Earl, looks similar....
Interesting point though - this design would be well suitable for tide - water has 800 times more energy than air - ok so yes it is much slower flowing. This design however has all the electronics and controlling mechanics at one end of the blade so could be placed out of the water (at the top) making easy access and less corrosion / wear and tear.

ERS are you involved in this technology as a single inventor or do you run a company?
I have in the past got companies to design parts of it but they found it a bit too complex when I asked them to make the blades (light enough) whilst still strong.


Evil Roy Slade

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Re: hey guys ! a new type of windmill (french site)
« Reply #41 on: December 20, 2007, 10:59:37 PM »
@mine

I have three businesses involved in custom NC machines, software for manufacturers and project management. Like most people I am concerned with our footprint on this planet and would like to do my bit to help.

However no good idea or machine or whatever will get anywhere unless it is profitable. That might sound capitalistic but it's the harsh reality. So before allocating major resources I need to be reasonably comfortable that the project will at least be self sustaining.

Our current internal skills in the aerodynamics area are very limited. But that's ok, I love a challenge!
Initially I might have to ask you some dumb questions so please be gentle! If the project becomes a goer the required expert skills can be acquired.

ERS


pese

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    • Freie Energie und mehr ... Free energy and more ...
a new type of windmill. Mail from Prof Dr Evert
« Reply #42 on: December 28, 2007, 11:10:25 PM »
Fred Evert

In English:

Best regards for holidays and best wishes for New Year.

2008 will be decisive for Alternative Physics. We all know many attempts
for solution of energy-problem made progress and we hope breakthrough
will come up next year. Just last months were rather exciting concerning
experiments with fluid-machines, as reported at News-at-Evert
www.evert.de/eft10e.htm

Two new and realistic proposals are presented: ?Windmill at Cellar?
www.evert.de/ap0701e.htm for autonomous power-supply of houses and
?Meander-Engine? www.evert.de/ap0702e.htm for drive of vehicles. I hope
you enjoy reading these pages - and good reasons recommend to check
these ideas intensively.

I wish you all the best.
Fred Evert
--------------

In Deutsch::

 www.evert.de/ap0702.htm

G.Pese

minesapint

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Re: hey guys ! a new type of windmill (french site)
« Reply #43 on: January 29, 2008, 04:53:31 PM »
Any progress on this?

I am still keen.....


eavogels

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Re: hey guys ! a new type of windmill (french site)
« Reply #44 on: March 19, 2008, 08:29:18 PM »
Hi.
I thought I had seen this before, and today I found where I had seen it.

This design is at least 150 years old.
It is in the book: 507 mechanical movements, from Henry T. Brown, first edition 1868.
It is design 486: plans of a vertical windmill.
Eric.