VAWT project

[Tom in NH]

I've been working on a VAWT based on Windstuff Ed's Lenz turbine. It's one of those trial-and-error type projects where I reinvent the wheel a hundred times, but I'm having a lot of fun doing it.

The turbine started out with a big diameter, 84 inches, and I soon learned it would only turn about 5 rpms. So I cut it down to 38 inches between the airfoils and I removed one of the three airfoils to try to lighten it up some. That improved things, but it still only turns around 30 rpms in a moderate breeze. I want to try to get it up to about 60 rpm.

A couple interesting things about this turbine: it responds to incredibly light breezes that you can just barely feel on your face. It has never had a problem getting started even with just two airfoils. It just doesn't turn fast in higher winds. Any ideas?

Pictures and a brief description are at www.altenergyweb.com/vawt.htm

[Tom in NH]

Let's make that url clickable link: http://www.altenergyweb.com/vawt.htm

[powerbuoy]

I would love to help, but ... I had built a similar unit. Unfortunately, I got less then 1 RPM with mine ... meaning it did not turn at all. I can truly see though that you put some serious efforts into it. Hope you figure it out.

Powerbuoy

[windstuffnow]

  Tom,

   My 3ft diameter runs at 56 rpm in a 6 mph wind ( has all 3 blades on it still --- at least last I checked ).  

   It isn't a fast running turbine, it has lots of torque and runs at a fairly high efficiency.  

   You might try making the blades the correct size for the diameter that will lower torque but increase rpm.  

   A company I've been working with built a similar sized Lenz turbine as my 3x4 and didn't include the nose in the overall length, basically made the tail to long.   It wouldn't run, wouldn't even try to start in a 20mph wind.  After they explained the dimensions of the turbine I told them to cut the trailing edge down 4 inches after which it started and ran in the slightest breeze.

    Small details can change the airflow considerably with this turbine.   Adding nothing more than some oversized wing shapes on the top and bottom of the wings ( winglets ) increased performance as much as 12% in the smaller unit.

.  

[Tom in NH]

Well, Ed, you're right. I should make the blades smaller so they are proportionally right for the diameter. But I don't what to buy any more aluminum and I hate the idea of taking my present wings apart. Maybe I'll just have to bite the bullet. Before I do, I think I'll increase the diameter back to the original and check performance of two blades and the improvements I've made. I've also been making small improvements here and there, making small gains each time. For instance, I took off the clunky 2x4 top cross piece and replaced it with a piece of 1/2 inch emt flattened on the ends and bolted through. I don't know if it was air flow or weight that I affected (probably both), but it helped. I will get it eventually.

Would you please describe your fascinating winglets a bit more? -tom

[IntegEner]

The day will come when the verticals (I call them the "verticals" - and the horizontals the "horizontals") become something worth while but they aren't there yet. Meanwhile lots of "tweaking" goes on (and on and on), otherwise known as the four T's - Try This, Try That. When others like yourself have discovered the depths of the errors they are making they disappear quickly from these discussions, leaving everyone wondering whatever happened to so-and-so (after showing marvelous photos of beautiful projects wrought with painstaking efforts often over many months' time).

My full length book-to-be-written, after some early beginnings to be seen on the IntegEner-W website as "Wind Theory", will have a title something like "Hello, Air!" with a subtitle of "The Wonders and Pitfalls of Extracting Energy Out Of Thin Air". No mention of "wind energy" or "wind generators", which have become such pejoratives to the public. Air is a substance, you know, and has a mass density ( 2 pounds per cubic yard ) and a viscosity ( in absolute terms, 180 micropoises at ordinary temperatures ). The need to start from the beginning applies here as well. Everyone these days is so conditioned to looking for the easy short cuts, the escapes into a new world that leave the humdrum and the unpleasant behind.

What is on the website is not bad as is, though. The Basic Aerodynamic Equation is there and this is something that could start a revolution all by itself. Few have "heard" of this because it doesn't just go back to the Wright Brothers, rather it goes all the way back to Galileo dropping two stones from the Tower of Pisa. Let's, God willing, get the foundation right and then maybe the rest will take care of itself.

Don't worry. The horizontals are not so "perfect" either!

Anthony C.

IntegEner-W

Tehachapi, CA

www.integener.com

[SmoggyTurnip]

I'm not sure but I think the point

you are trying to make is "VAWTS" arn't

as efficient as "HAWTS".

In terms of words per ideas, I think

your efficiency could improve.

.

[kitno455]

you're doing better than me.

all i heard was blah, blah, blah, thread hijacking, blah, blah, blah...

allan

[TomW]

Some folks do like to keep saying things hoping they become fact from simple repetition..

[kitno455]

and some folks dont use their banning capability often enough

allan

[windstuffnow]

  Isn't that how advertizing works?   If it's mentioned often enough someone is bound to buy it.  Doesn't matter if it's good or bad right or wrong.  What is it that "tastes good like a cigarette should".... ?   An ad that hasn't run for ?? years but I'll bet most of us old timers can answer that one like it was second nature whether you smoke or not.

  I guess my problem isn't with Anthony personally, Just the way he comes across.   He tends to discourage the builder and make it sound like he has the "wholy grail" of extracting energy.  Unfortunately, he offers no real machine ( that produces work ) as a proving ground for his claims.

  Personally I would rather encourage anyone with an interest to build and learn.  So what, if it doesnt work as well as it could.  They did it, it worked and they reap the benifits then they will continue learning and building.  Learning and success came from failure... how many light bulbs were built before one actually worked?  Did he listen to those "nay" sayers?  

.

[Tom in NH]

Meanwhile back at the ranch...

Today I put the two blades on a six foot crosspiece. The breeze was fresh and at one point it got up to 45 rpm. Those big wind buckets definitely like the larger radius. Good torque too. Maybe I should try building a new stator with smaller wire and more windings. Maybe I should try building a transformer. I hope to hear more about those winglets Ed spoke of. --tom

[Ungrounded Lightning Rod]

Adding nothing more than some oversized wing shapes on the top and bottom of the wings ( winglets ) increased performance as much as 12% in the smaller unit.

Air or water will run around the end of an airfoil/waterfoil, removing much of the lift from the outer part of it.  Adding winglets impedes this flow, paying back far more than they lose in added drag.

They're usually left off in keels, rudders, wings, props, etc. because it's easier to just make 'em larger and the winglets can add other pathologies.

(Sailboats designed to be navigable in shallow water (or trailerable without having a retractable keel), for instance, may have "wing keels" - shortened keels with a double winglet at the end to make them perform like a longer fin keel.  Downside is that when the boat heels the hull shadows more of the keel and you lose more of your resistance to side force.  So you can't sail as close to a strong wind as you could with a fin keel.)

[Ungrounded Lightning Rod]

(Hit post before I was finished.)

The Lenz rotors I've seen here are mostly short compared with their width.  So they stand to gain a lot by adding a winglet.

[windstuffnow]

  Tom,  The winglets are nothing more than a top and bottom plate that are about 2-3 inches larger than the wing.   They simply keep the air from flowing off the wing and creating turbulance in those areas.  Just another way of controlling drag on the upwind swing although it may add extra cupping for the downwind side.

  Think of it as a thin plate the same shape as the wing only larger by a couple inches.

.

 

[windstuffnow]

  Here is a quickie graphic for the winglet.   It's basically a very low tech version of the real thing and could be made much better if one wanted to.   The low tech version works very well.

 The graphic shows the top with the winglet, the air flows around the wing without "slipping" off the edge.  The bottom with out the winglet, the air will slip off the wing creating vortices or eddy currents.   A simple addition that is cheap enough to make the gain worthwhile.

[IntegEner]

In so many words, wind energy has been nothing but a "cute puppy" of a technology, even on the professional level, and needs a better foundation in theory than it has. When someone like myself has already seen electrical power production and development projects leading to same, the challenge of building a small generator to produce a few amps doesn't look very inviting.

I wonder, as I gather from Mr. Ed Lenz's comments, if he has ever seen the www.integener.com website. Try it, you will like it!

The real meat of wind energy is in the interaction of the wind and the blades. The last chapter has not been written on this and it is often given little attention.

The verticals suffer from two main problems:

1. Their blade swept areas are not equivalent to those of the horizontals. A factor of 2/3 must be applied to them to find an "effective" swept area. This means the verticals must be 150% larger than the horizontals for the same power just to begin with.
   
2. The parasitic friction drag of the verticals blades moving through the air, especially on the upwind side of the their rotation is much greater than that of the horizontals. This is often addressed by making the blades very thin, as can be seen on the Darrieuses with their bent, thin blades. Many copy cat projects, especially the H-Rotors, never learned this and so they made thick blades, which was their undoing.
   
   

The drag verticals are even less inviting, much size and weight with little power.

I am a moderate in my views. Others are much, much stronger in their criticism of the verticals. I, at least, believe they have a future. First, more wind energy inventors and devotees must learn the Basic Aerodynamic Equation!!!

Anthony C.

IntegEner-W

Tehachapi, CA

www.integener.com

[vawtman]

relax anthony everything will be ok.

[kitno455]

"The real meat of wind energy is in the interaction of the wind and the blades. ... it is often given little attention."

little attention? its the point of 1/3 of the posts on this board! just cause we are not using your as yet unwritten book to do it, its not happening?

allan

[electrondady1]

yea, but antony they look so cool when they spin http://www.otherpower.com/images/scimages/2793/little_erma_004.avi

[johnlm]

Interesting.

Anthony wrote:

> the challenge of building a small generator to produce a few amps doesn't look very inviting.

I wonder, as I gather from Mr. Ed Lenz's comments, if he has ever seen the www.integener.com website. Try it, you will like it! <

I went to your web site, and in light of your comment above, if building a small wind generator to produce a few amps doesn't look very inviting, where does building yard ornamental wind mills with no generator at all rank?  Other than the real windmills on the mountains in the background all I saw was yard ornaments (sophisticated looking tandem bladed units freewheeling in the wind). Given the smoothly written words I saw in your comments in this post, I was expecting to see something pretty sophisticated that produced power.  Maybe I missed going to all the various pages, but the ones I went to just seemed to be more of the same.

Maybe if the big guys with the big windmills in the background on your pictures read your web site they would tear all those power producers down and start over, as they are surely doing something terribly wrong.

John

[TomW]

John;

I think, by now, it is clear to all but the most trusting of souls that Anthony only has one mission here and that mission is to draw in hits to his website so he can eventually sell someone something. Not sure exactly what,  but his continuing efforts to convince folks he has the holy grail of windpower when he has apparently not built anything that makes even one watt while denouncing DIY efforts is hostile towards this website and the folks that do rather than talk.

/ end rant.

Sorry to hijack the original thread but this needed to be said. I, for one, am getting very tired of these tactics.

Stoning is a bit cruel but perhaps a simple exile is in order.

Cheers.

TomW

[WXYZCIENCE]

Anthony C. I am new on this board. In regards to puppy dogs and such. Some of us post our stuff on this site to show others our work. You sucked me in once.  I don't read your posts anymore. Joe.

[stevesteve]

OK back on topic!

Tom, how stable does your stand seem to be? I would imagine that a VAWT like yours (looks great by the way, nice bit of design/maufacture) produces quite a lot of sideways thrust, equivalent to quite a reasonable diameter HAWT.

Do you think that would be sufficient for a 'productionised' turbine or is it just for the design and test phase?

Cheers, Steve (carefully avoiding getting involved in the discussion about wobbly garden ornaments!)

[electrondady1]

 i think i'll name my next windmill "cute puppy" !!

why doesent some one maill tony plans for a real wind mill

 when i first joined the forum i found him to be a distraction but it doesen't take long to find out he's blowing smoke.

tom ,i want to build a copy of lenz2 as you have done, i remember when ed was first discribing the lenz 2, the flatt on the vane needed to be exactly 99 deg. to a radius. if all the proportions are the same as ed's why won't it speed up?

[ghurd]

Maybe it ain't perfect yet, but at least yours works!

(never got my tiny one to more than barely turn, let alone 'spin')

G-

[windstuffnow]

  ghurd,  I remember you had some problems with the small one.  After you said that I built a 1x1 ft turbine to see what kind of problems I ran into.   The little one I built didn't spin very well either.  I played around with the wing angle until it would start in low winds.  Not a real power maker but it ended up working fairly well yet still no where near as well as the larger units.   I used some new and fairly stiff 3/8" bearings with the unit so I figure they were sucking up a few watts and if you consider the little machine will only make around 5 watts in a 15 mph wind, lower winds provide barely enough energy to move the grease around.   I might eventually turn the little one into an educational kit as soon as I figure out a way to cast the wings in plastic...

.

[nothing to lose]

"What is it that "tastes good like a cigarette should"

I know that one

But I'd rather Fight than Switch

As long as I don't have to walk a mile for a Camel.

Then I would be too tired to dance, even if that pack does have great legs.

 You made some great points there Ed.

[nothing to lose]

"Stoning is a bit cruel but perhaps a simple exile is in order."

I don't have an opion on that which I would want to express. However I will say that if  it is generally agreed he should go and that his site is useless then he should not be parrasiting here.

As  parasite I mean many search engine spiders will use various ways to rank sites in the order they apear in searches. How many links are pointing to a site and the popularity of the sites with the links has alot to do with the rankings.

SO everytime he posts his links here and other popular sites he is trying to up his ranking in the search engines. Trying to get closer to the first results returned for searches which of course provides more hits to his site.

Rather he is doing that on purpose or not, that's what he is doing.

Since he has all the answers I would like to see some reall pictures of HIS off grid wind powered home and shop, and details on HIS wind gennies making all HIS power for him.

 I don't think I have seen any of that here though from him.

That's kinda my opion on the subject, if he has all the answer then stop rambling babbling nonsense and do some real posting of facts with pictures.

I don't post much for pictures, but I don't claim to have the holy grail either, and I am not looking for hits to any website as a parrasite. The only thing I have to sell is the #29 arcs and that is only because people wanted them and could not find them.

Well, back to what I came here for, see what your doing with the Lenz2 design. An look at your pics of what you built.

[nothing to lose]

I came, I saw, I like.

Nice pics on the website. I like that hammer form for the ribs. Does that produce a crimped curve then or once hammered out does it end up fairly smooth?

[Fiddlehead44]

I may not agree with what you have to say, but will defend to my death,

your right to say it! If someone has an opinion that is counter to yours,

you want him banned from this board? BTW, repetitive advertisments turn

me off rather than on.

            Fiddlehead.

[Volvo farmer]

Rather than stoning or banning, perhaps it is in everyone's best interests to provide Anthony with a nice long piece of rope which he can do what he likes with. Should someone wish to research this individual before purchasing something from him, perhaps they would be lead to a thread like this one and they can read other's opinions about him.

[ghurd]

I think mine was just too small. Never did have it out in a good wind.

G-