Wind Turbines

[Cuicui]

Simplify by increasing performance ... The dream for all DIY enthusiasts! well done Francis for this superb work! Perhaps there will be other improvements and simplifications ...
As a generator, couldn't a small recovery car alternator do the trick?
A+

[Lord Francis]

Hello everybody

I allow myself to relaunch today this post dormant for 2 years, because I have something new: see my site:

http://soupl.eole.monsite-orange.fr/

I await your reactions:
1- on the choice I made to distribute this invention under "Creative Commons".
2- But especially on this invention itself.

[bernardd]

Congratulations on the principle of dissemination! The principles of free software finally arrive in the field of matter.

Funny, just in time compared to this discussion started on Friday:
https://www.econologie.com/forums/post193694.html#193694

On the wind turbine, the principle of flexibility seems to me completely original. On the form, it reminds me of this concept so recent:
http://www.nheolis.com/fr/index.php?page=nheowind-3d-50
We can imagine a hybridization crossing in the future :-)

[Superform]

Well done for sharing!

Would it be possible to have examples of suppliers for the materials used?

[Lord Francis]

Hello,

Thank you "bernardd" for the link to this new wind turbine that I did not know. It is indeed very original. It looks more like my second proto with cone-shaped sails that could close and recede to the rear in strong winds.
When copying it must be dangerous because it is patented ...

For "superform", the necessary materials are very easy to find: fishing rod tips for the frame, sailcloth or polyurethane sheets for the blades.
In short, my 1m20 diameter models cost me only a few euros.

[bernardd]

Attention, it is not a question of copying to market: it is prohibited and it would not be very nice for this small company.

And as talking about them advertises them, I think the result for larger projects is positive for them :-)

Copying for personal use is completely authorized and it was even the whole objective of the patents originally: to give a commercial monopoly of 20 years, against the publication of inventions, contributing to the propagation of ideas and technical education.

The shape of the "chistera" blades is original, aerodynamically validated it seems.

But for me, the clever "trick" is the rearward lengthening of the blades which allows them to be held by "spokes" fixed on an extension of the axis towards the rear. This thus makes it possible to stiffen the blades in a very simple and very light way too.

I also note that the centrifugal force naturally tends to spread the pale, but I do not know the relative part of this effect to counter the aerodynamic forces.

In short, I find this Rhéolis invention very elegant, from all points of view.

[dedeleco]

Very interesting, given its simplicity of implementation, its flexibility, while being fairly effective in shape.
It would be good to give more info on its real characteristics coupled with a usual simple cheap generator recovered, for a given diameter, to know its power compared to the diameter according to the wind speed.
It would be good to have an idea of ​​the decrease in performance compared to an efficient wind turbine of the same diameter, which is worthwhile, by the simplicity, and the resistance to strong winds by flexible deformation and tearing of the fabric of the wings.
I have the impression that the performance is not bad.

It can be done in very small wind turbines mounted in double opposite directions on a kite, to test.

The effect of centrifugal force can be increased by additional masses on the rods.

[Lord Francis]

I am currently testing my largest model (1m in diameter) coupled with a small marine wind generator (Aerogen 20) of around 6W. The 300 original blades of this wind turbine are also approximately 6m in diameter. Mine only has three blades, but they are wider at the base.
My first tests are conclusive in light winds (force 2 or 3). However, it seems to run a little slower.
I'm waiting for the next Mistral blow to test it in strong winds but for the moment it's raining in the south ...
I will keep you informed as soon as Eole arrives.

[bernardd]

However, it seems to run a little slower.

Normal, according to this site: http://www.mwands.com/index.php?main_pa ... 866dafbdb5

They explain that it is the number of blades that makes the speed of rotation in light wind.
http://www.mwands.com/tech/?p=464

You can also imagine putting a larger "hub": all the wind that passes in the middle is lost, the more it acts towards the end of the blade, the greater the leverage effect.

[hic]

For a modern wind turbine:
By sailing for more than 40 years, I have had the opportunity to appreciate these superb ecological machines that are our sailboats which can sail with the force of the wind using only a few square meters of fabrics.
Why not use sails to recover the force of the wind?
Obviously, this has existed for millennia, the "Cretan mills" of the Aegean are the best examples. Besides their primary functions, to draw water or grind grain, they are beautiful, and have even become an aesthetic symbol of the Greek islands.
The principle of these triangular sails, wound on spars, is brilliant, but it has one disadvantage: it requires constant surveillance. Their millers had to set the right sail area, day and night, under threat of destruction with too strong a wind (the Meltem which blows in this region often reaches the force 8 ...).
Our modern sailboats have taken up, by perfecting it, this means of reducing the sail by winding on the forestay for the jibs or even inside the mat for the mainsails. These processes, now generalized on sailboats, are perfectly reliable and operate in the worst weather conditions.
So why not take up this ancestral principle using our current techniques?
A modern sail wind turbine whose winding of the sails would be ensured by electric motors electronically controlled by the force and direction of the wind Measured by a wind vane-anemometer, is perfectly achievable. The necessary material, of marine quality, therefore resistant to extreme conditions, is easily available in all dimensions, since already broadcast on a large scale in yachting. For the realization of the sails, very important progress has recently been made on the quality of the fabrics making them more resistant and perfectly suitable for continuous operation.

Obviously, for high power, a wind turbine will never compete with large three-bladed wind turbines, technical problems would be insurmountable with sail surfaces too large.

By cons, in realistic dimensions (less than 10m diameter), so for small or medium powers, it would be as effective as a traditional three-bladed wind turbine without being more expensive (its cost would be comparable to that of the rigging of a sailboat medium sized).

Moreover, by turning more slowly, it is More quiet, Which would allow to use it in an urbanized but windy as the coast and not necessarily in open country or offshore as with the current wind turbines. Another advantage of this lower speed: it would spare the birds unlike the large trials that make real carnage ...
It would also be more sure for a sail that is torn in the storm is less dangerous than carbon blades playing "flying sabers".
And above all, it would undeniably More aesthetic; And this last quality is far from negligible with regard to the main argument of the anti-wind lobby ...
Its modest dimensions and its specific qualities would facilitate geographical implantation even in inhabited areas, so close to electrical needs. Why not equip them, for example, with marinas, to ensure electric autonomy or roundabouts for their lighting?

A small self-regulating wind turbine :

For domestic use, therefore with small dimensions (less 2 or 3 m diameter), therefore of low power, the control by electric motors of the sails becomes too expensive, and with an energy efficiency too low if the wind is irregular (Which is always the case with small wind turbines close to the ground). With a regulation too often solicited, the electricity produced would only serve to operate the winding motors ... This small wind turbine with sails would certainly decorative, but unfortunately ineffective!
We must find a way to be self-regulated
To wind the sails on the spars, in addition to the force of the wind, the only usable force requiring no external input is the centrifugal force.
Being able to use the weight of the counterweight deviating from the axis as a function of the speed of rotation and therefore of the wind force would be a good solution because it would make the wind turbine autonomous. Nothing invented: it is James Watt who, in the 18ème, had the brilliant idea of ​​the regulator with balls)
Other interest: the speed control function. The mass of counterweights acting as a flywheel could make the wind turbine less dependent on wind variations, which would be conducive to electricity production; The generators working best at a regulated speed.

The idea is therefore attractive on paper, but its implementation reveals many difficulties, as I was able to discover them by making a model 1m20 of diameter (see photos).
1- How to make a ball regulator that works in the vertical plane? Indeed, in this case, gravity intervenes: the upper ball tends to "fall" towards the axis and the lower ball to deviate from it. Only one solution: to connect them by a deformable double parallelogram centered on the axis, which neutralizes the gravity. Easy to achieve for a couple of counterweights, it is much more complex when there are several.
2- The centrifugal force must be sufficient to allow the winding, so that the weight of the counterweights is adapted to the surface of the sails. This essential data is difficult to calculate, only solutions found: a position adjustable with respect to the axis, and ... the trial and error.
3- It is necessary to transform this axial displacement in winding of the sails. I did it by copying what is done on the sailboats by a rope wound on a drum at the base of the sails It is in closed circuit because it has to operate in both directions: winding - flow. And to avoid friction, all crossings must be done on pulleys, the end being put on by a sandow.
4- Another variable that must obviously be taken into account: the length of the "tapping" used to "border" or "shock" the sails. This time, the ball regulator easily gives the solution: by fixing the tapping on the counterweights, whose centrifugal or centripetal movements according to the speed of rotation allow the sails to be automatically adjusted according to their winding.
5- Once wound when the wind is strong, the sails must be able to unwind when they are weak, so it is necessary to provide return springs or sockets on the regulator for its return to the center. Return to zero).

Practical results: The model works well in moderate winds (forces 3 to 6) but I have not tested it yet with storm winds. It is still perfectible for weak winds because the frictions are still too great especially for the axis of rotation which for the moment is not mounted on ball bearings. Finally, electrical coupling with a small generator remains to be carried out.
NB: For this model, the centrifugal regulator may seem oversized (therefore unsightly, which is particularly harmful for a wind turbine) but I think on a larger scale it could be proportionately less important. In addition, to be less visible, it could be placed behind the sails.

Hi Ternel Francis

Your sail system is perfect for simplicity.

It allows to adjust the surface of sails continuously
depending on the strength of the wind

For safety in case of gale,
The cord serves as a fuse. . .

you fix the sails with calibrated ropes to break
during a gale
which will prevent you from damaging the sails and the reinforcements and the mast.

To repair it will be enough for you to tie a knot
with broken strings

Example:
for 6 sails wind turbine and for a total pressure of 100 KG per KW

we should calibrate the rope to a break for a traction of 20 Kg

Which secures the mat at the same time