Protecting a homemade windmill (wind generator) from strong winds. Wind-driven water aerators Rotary assembly and current collector

Wind water aerators

I decided to post my work in a separate thread.
There were many experiments and tests (and now, at the moment, all new ideas are being tested), many mistakes, but successful solutions were also found, which, by the way, have already worked to save the fish.
Why a separate topic - I suggest that those who are interested discuss exactly the constructive parts. Maybe together we can find better solutions.
An Internet search did not give any results either 3 years ago or now. Now there are links to my videos on YouTube
To be continued...

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

So how it all started:
Having bought a plot with a reservoir, but without electricity, I ran into the problem of a winter freeze. Total.
I started looking on the Internet.
The idea of an electric wind generator disappeared immediately. It will be stolen in the field. Together with electrical equipment for water aeration.
The same fate would await solar panels.
I decided to try to find the use of wind energy directly, by simple mechanical transfer of wind energy to water.
Created a topic, for a possible hint from the members of the forum.
Along the way, he studied all possible types of windmill blades. I learned a lot about the strength of the wind, about the non-proportionality of its strength with an increase in speed, its instability and so on.
The most effective energy from the wind turned out to be the most technically difficult to implement.
The simplest and most forgiving execution flaws remained the Savonius rotor and the multi-blade (chamomile).
In the "chamomile" was tempted by the possibility of using small winds. But at the same time, the requirements for increased strength, since it breaks badly in hurricane winds.
I tried to make a small daisy, only 1 meter in diameter. Unfortunately, there is no photo of that creation. Of course, "on the knee" did not work out qualitatively. But he was spinning. In reality, I saw that there is energy in the air.
But with "chamomile" the rest turned out to be even more difficult to implement.
It was necessary to make a landmark in the direction of the wind, and at the same time transfer energy to the water. It was impossible to do without the most complicated lathe. And plus the fight against breakdowns by a hurricane. It turned out to be quite an expensive pleasure.
I began to examine the Savonius rotor.
It turned out that it is the most inefficient in terms of wind energy (efficiency).
But it turned out to be the easiest to perform. His performance forgave many flaws in performance.
To be continued...

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

The first savonius windmill I made was also not captured for history.
As I thought at the beginning, it is necessary to make it as light as possible so that it starts with minimal wind.
Therefore, a meter-long M6 hairpin was taken, and two halves of a transparent plastic bottle were put on it. And there were two such blades. At the top is a bearing, at the bottom is a tin plate that drove water.
The structure worked. She spun in almost complete calm. You can't even feel it on your face, it's spinning.
But there was very little energy. The wind collection area is too small. And at night, when it was completely calm, it froze.
I went further. I had a bunch of buckets at work. I decided to make blades out of them. They were affordable, they were bigger and stronger.
Here in the first message there is a video of these windmills, and a description. Therefore, I will not repeat myself.
There were 8 such windmills per canal of 10 acres. She seemed to be working. But there was a big minus - they constantly froze on a calm night, and every morning they had to be cleaned.
And in the spring it turned out that they did not work. The plague passed, there were a huge number of corpses. Maybe the pestilence was not total.
But on these windmills, I understood one thing - how to arrange the blades relative to each other. They should not have been attached to the axis of the windmill, but overlapping each other. Only they worked much better.
For the next winter, I decided to change everything drastically. For I already had an idea more or less what I need to do.
The first is to increase power.
The second is to make an antifreeze so that it does not freeze at night and the windmill would work autonomously and without complete stops.
The third is to make the structure rigid, that is, so that the windmill does not hang on the upper bearing, but stands rigidly fixed.
Fourth - instead of a tin for a water mover, make a propeller. This will give more sweats of the code and its uniform movement.
For the blades, a 200 liter plastic barrel was used. At first I made a bucket from above, I was afraid that I would not start from a dead point. I will say right away that it was a delusion, because it was removed during the repair of the windmill.

Made antifreeze. (all on video)
http://www.youtube.com/watch?v=RYbgkM5LUCA
The windmill is mounted on a frame of stakes both from below and from above.
For the propeller, the fan blades of the radiator of the car were used.
At first they put, like small windmills from buckets, on two stakes, without spacers. Subsequently, the hurricane put the entire structure into the water. then had to after freezing all cut down.
so, having made a windmill, we went to install it. It was windy. After installing it, we were amazed at the energy. The water literally churned.
Arriving a day later, instead of a 40 cm hole under the windmill, there was a polynya of 3 meters. The ice at the time of installation of the windmill was 42 cm. This washed everything out.
I can say that this first windmill was repaired only once - when it was laid down due to the lack of braces. Having installed the braces, Don't razi again did nothing until spring. One day it was a very frosty and windless night. Having arrived at the urt, we saw a frozen windmill. The ice was more than 5 cm. They were not specially cleaned. The wind was already picking up in the morning. By lunchtime, the polynya had fully recovered to its previous size. When there was a thaw, the polynya increased to 6-8 meters in diameter. In the spring, this place melted a few weeks before the whole pond.
The result was pestilence, but not strong. There were many live fish to be seen. The windmill worked, and very well. It was clear that there was life in the pond.
It pleased. This showed the viability of the idea.
Yes, Here is the spring video. I stepped on the bottom bar and it broke. They left it like that, and then the wind threw the windmill on its side.
http://www.youtube.com/watch?v=rdgi9v5968U
Pushed it and it worked.
http://www.youtube.com/watch?v=kzFHXMnKItg
By the way, the windmill worked then for almost the whole summer. During this time, he passed the test of strength. Then the plates holding the bearing were rubbed, and it fell into the water.
To be continued.

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

The next winter, that fallen windmill was taken out from the thinnest ice, it was sorted out, and immediately put. I have already begun manufacturing another windmill according to past experience. Larger.
What was planned:
1. It was decided to do it completely in the frame. This gave very good alignment, which removed unnecessary interference. For in the smallest wind any watt of energy is important.
2. Make with two blades. This is to eliminate the "dead point".
3. Plus, it was conceived due to the increase in power to make a reduction to increase the speed of the propeller.
4. There was an idea to make the lateral movement of water. It turned out that in the previous version, the screw enriched the water quite locally near the windmill. By forcing the windmill to draw fresh water all the time, more oxygen was absorbed by the water, and it should also be good to degas from harmful gases.
5. A slight modification of the antifreeze. In the previous version, a polyurethane bushing was made under the stuffing box. The oil seal did not slide as well on it as on metal. But since this sleeve is in the water, it was decided to make it from stainless steel. Plus, polyurethane changed its shape very much from heat and frost, which also affected the geometry.
What happened:
1. Done. Fully justified the idea.
2. Done. It also fully justified itself. Plus, due to the increase in height and the totality of energy removal, this design turned out to be 30-50 percent faster than single-blade windmills.
3. It didn't work out. I tried to make a reduction through bicycle stars. And there, precise turning work was needed, it didn’t work “on the knee”, the chain was constantly thrown off. The idea was not implemented.
4. It was done. The idea paid off. Subsequently, this part was disassembled and done differently. Another option is currently being tested. Why the other, I will describe a little later. The idea is to make it more functional.
5. Done. This change paid off very well. The resistance has been greatly reduced.

To be continued...

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

So, in the year when the frame windmill was made, there was no weather. The ice rose, but 5-7 cm, and then it covered with snow. He was loose, it was scary to go out. Put on 5 cm of ice. very uncomfortable. The edge of the polynya, it breaks off, you can't get close. I swam waist-deep once (I managed to grab the poles and jumped out).
Set. But during the installation, the windmill turned a little, and the idea was a little knocked down: there was an idea to direct the jet from the lower side propeller exactly along the channel. But in the end it shifted to the side, and went to the side of the canal.
And so the windmill stood until heavy ice, when it was possible to approach it for work. And a third windmill was placed on the heavy ice.
You can see an oblong polynya from a windmill. It's so blurred by the side propeller.

On good ice, the windmill was laid down and tried to turn in order to direct the stream exactly along the channel. Due to careless movement, the windmill fell loose, and the frame slightly bent. Imperceptibly, but it was clear that it was wiping somewhere along the landing nests. Then they found this place, and the rubbing place was removed. But the fact remains: you have to be very careful.
But still the windmill could not be turned. So I left it.
Then it was contrived to make a lateral movement in a different way. Take the cable from the speedometer and transfer the torsion force through it immediately to the propeller located sideways.
To be continued...

Registration: 29.05.11 Messages: 11.751 Acknowledgments: 4.345

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

In the course of using / testing the windmill, all sorts of "sores" came out.
For example, in the antifreeze, at first they made a chair on the stuffing box made of polypropylene. it turned out that it changes its geometry in the cold, water slowly collects in the antifreeze, and one fine morning you see a windmill standing up like a stake. We decided to remove the antifreeze, order a stainless steel sleeve from the turner and replace it.
This opened my eyes to a new design flaw. It was necessary to make the antifreeze detachable from the axis, without removing the windmill itself. At first it was made from a common hairpin. I had to cut the hairpin with a hacksaw, and subsequently connect it with a long marriage nut.
But even sawing the axis, it was not possible to remove the anti-freeze without removing (laying on ice) the frame of the windmill itself. It turned out that the bearing in the lower seat and the propeller after it were not allowed to be pulled out. The bearing came out of the socket, but the propeller did not give.
It was necessary to lie down and take it apart in detail (bent over the hole, where more than one dropped key drowned), but already in my head an idea arose how to get around it.
When they put it, I decided to make the water drain to the side not with tin, as in the video, but through the speedometer cable. The last video shows how. It turned out that "on the knee" the cable could not be clamped well.
As a result, the tin was removed (or rather, knocked down, as it was for welding), and it was no longer possible to put it back on the ice, and it did not work out with the cable. Did it several times, all to no avail.
And so the windmill worked until spring.
In the spring, with a heavy hurricane wind, the windmill broke. I must say, one of the three spring winds broke and break every spring. In different places. This time the frame and the whole structure survived, but the blades could not stand it. One blade was torn off, it jammed in the frame, then the lower blade was scrolled by the wind along the hairpin, slid down on the thread to the very bottom and jammed. Or maybe vice versa, I don't know. But the result was this. But it was already in the spring, the ice was decrepit, the polynya was huge. The winter has already passed.
So I left the windmill. It stood all year until this winter.
This year this pond was lowered and left to freeze. But I have reclamation reduced to the main channel, water constantly flows there, and does not freeze. Filmed in the middle of winter, on 5 cm ice, and then the partner failed.
Having removed it, they saw another design flaw: it was necessary to cut everything again in order to remove the blades for repair.
This has been fixed. Now every detail from each compartment of the frame is removed autonomously, without parsing neighboring parts.
I noticed an interesting thing: where the caps were above the bearing, the bearing seemed to have just been installed - all in oil and works like new. Where there was no cap, the condition of the bearing was unimportant. Now we cover all the bearings with a lid and pass the axle hole with silicone
Rearranged all windmills on 6 hectares.
But 3 pieces per 6 hectares are very few. I will add. But in order to add, it is necessary to work out the design to the ideal so that it can work in a completely autonomous mode.
To be continued.

Registration: 06.10.08 Messages: 16.642 Acknowledgments: 18.507

Having rearranged the windmills, I decided to make antifreeze from a metal pipe, with a lathe for bearings. The fact is that the first option with a plastic pipe did not give exact alignment, which also gave extra resistance when scrolling the antifreeze.
The assembled precise antifreeze made on a lathe pleased with its symmetry. Resistance has decreased, and very significantly. He was almost gone. Even at the smallest wind, the windmill did not stop from the impact of the clamped antifreeze. This metal pipe was painted black so that the sun would help warm it up.
But then there was another factor that I did not take into account. The metal pipe was much more thermally conductive than plastic, and in a calm weather it would freeze through the pipe three times deeper than the ice itself grew during a calm night. Because of this, even though the antifreeze was installed 10 cm below the water level, it froze. The cold passed deep into the pipe, frostbite the pipe, and captured the pin from below. Through the transparent ice, one could see how the whole pipe was covered with needles of frozen ice in the depths. Beautiful. But harmful.
On one windmill, where the antifreeze was lowered deeper, it did not freeze there. Now I'm thinking about how to do it better - either put it in foam plastic, or lower the anti-freeze pipe deeper.
Haven't decided yet. there were winds at night, so while they are working, let them work.
I still thought about pushing the water sideways. To do this, the turner was ordered to press the cable into the stud. Shown in the last video.
We made three of these ropes.
The first time the propeller was mounted on a hairpin. But during rotation, the windmill collected the cable in a heap, twisted it. But it worked, the movement of water was strong.
The next day, we decided to fix this contraction, and made a lower stretcher (one of these days I will try to make a video), where everything was already rigidly fixed in the frame. And the second was made on a plate to put on a single-blade windmill. Arrived, and the first cable is broken. They attributed it to a bad installation, which twisted it.
All assembled and installed. Everything worked just perfect.
It was the day before yesterday. Today I arrived and I see that both side propellers are standing, and the windmill is spinning. So, both cables broke again. So, it turns out that the cable does not hold. The idea turned out to be problematic.
Now I will return to the original idea, when the propeller is on its axis, and the water itself turns due to the tin obstacle.
To be continued...

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11.08.2010, 23:22

Left side of the equation.
Force per propeller in Newtons (P) = 0.5 * 1.23 * propeller area in sq.m * wind speed squared.
Moment (M) applied to the center of rotation of the windhead in Nm = P*distance from the center of rotation to the center of the propeller in meters (offset of the propeller axis).
Work when turning the head 90 degrees (Pi / 2) \u003d M * 1.57
The right side of the equation must equal the left side.
Right part
Tail lift work = mgh
m weight in kg
g - 9.81 gravity
h is the height of the point at the center of gravity
h= distance in meters from the center of the tail kingpin to the center of gravity * sina (sine of the kingpin angle)
Although it is not very clear to me why there is no tangent, although they are close

11.08.2010, 23:34

My tail folds sharply, and for a long time the angle of the folded tail of about 60 degrees does not unfold, the generator stops generating current, the screw slows down to such an extent, apparently it is necessary to focus on 45-50 degrees so that the screw continues to do useful work - all this happens at 17-23 m/s long time ago there was a hurricane trees were falling

Added after 4 minutes
Thanks for the formulas, I'll make a sign in the near future, as I comprehend everything you said. I'm interested in making a more efficient tail, maybe add a hydraulic shock absorber and spring, because. the folded quota does not want to maintain the speed of the windmill and unfold to the desired angle, when it could be used, for me 10A the ammeter goes off scale during a hurricane, the tail folds up, the current drops to zero then again and so it cycles during a hurricane, but you can always do it 10A issued :)

11.08.2010, 23:50

I myself have not really figured it out yet, but I'm sure it can be done with a spring. Remember the dynamometer, we hang 1N, the spring sags by 2cm, hangs 2N, sags by 4. It seems that it should be like this here too, do not change position abruptly. We will work on this.

13.08.2010, 16:08

13.08.2010, 18:43

Dima's tail returns by itself, under its own weight without springs? I understand that the windmill (generator) is always deflected by some degree, the stronger the wind, the greater the deviation?

13.08.2010, 23:27

I have doubts that the tail will smoothly move away from the wind. Here the equality of forces, and as they coincide, the tail will leave. I haven't experienced it yet, and it's only intuitive. The spring, yes, can smoothly deflect. It is necessary to ask around those who have done such a tail more than once. Let's say Mikola.

17.08.2010, 00:35

I just didn't do that. Did others but nothing to brag about. Apparently, whatever one may say, you will have to test and check everything. I'll probably do this in the winter.

02.09.2010, 22:47

Dima, you translate well, see http://www.thebackshed.com/windmill/Docs/Furling.asp

19.01.2011, 13:37

Guys, can anyone help me deal with (TAIL DROP) and translate the calculations? : http://www.thebackshed.com/Windmill/Docs/Furling.asp

19.01.2011, 16:03

goga65,
http://translate.google.ru/translate?js=n&prev=_t&hl=ru&ie=UTF-8&layout=2&eotf=1&sl=en&tl=ru&u=http%3A%2F%2Fwww.thebackshed.com%2FWindmill%2FDo cs%2FFurling .asp

19.01.2011, 16:19

Valeriy, Thank you, but not everything is clear. Did you count the tail to your VG or from the "balda"?

19.01.2011, 16:28

I counted according to Vladimir's formula.
.php?t=67

19.01.2011, 17:31

Guys, who can help to calculate the tail specifically: d = 1.5m, into the wind 20m.s. P=300W(if needed)?

19.01.2011, 20:49

For one and a half meters, in principle, protection is not needed, and in my opinion 20 m / s is too much. protection by this time is no longer needed.
I can only help with shock absorbers.

19.01.2011, 22:38

Goga65, read carefully, thoughtfully. Everything is clear there. Once again I bring Vladimir.
Normal 0 false false false MicrosoftInternetExplorer4 Consider the mechanism of operation of the oblique king pin. the operation of the entire circuit is similar to the operation of a screw thread. During the operation of a screw pair, the equality of the work produced by the torque of the rotating screw and the screw working on a counter force is observed. Thus, the moment applied to the propeller axis in our case depends on the wind and is well reflected in the table that I gave, the table, of course, must be corrected by an order of magnitude, as Viktor Afanasyevich accurately noted, God bless him. Because Since the movement of the screw is linearly dependent on the angle, it does not matter which angle to consider for comparison of work, based on this we will consider an angle of 90 degrees for the convenience of calculations, 90 degrees is P / 2 radians. Knowing that in the initial state the center of gravity of the tail is removed by 2 meters and the weight of the tail is 50 kg, when the protection is triggered by 90 degrees, the work done when raising the center of gravity of the tail is 500 * 2sin a, where a is the angle of inclination of the kingpin, the work done by the head (from the second side of the equation) will be equal to the moment from the table multiplied by P / 2, so the general equation for calculating the inclination of the kingpin is as follows:
M*P/2=500*2sin a
solving the equation for any moment from the table relative to the angle a, we get the angle of inclination of the kingpin for the operation of the protection in the wind corresponding to this moment.

31.01.2011, 20:32

I designed the VG from a Bulgarian motor, but didn’t finish it because it turned out to be very heavy, for a thin mast, now I’m trying to finish the design. I’m trying to make a multiplier (1: 3.5) from a pulley (in my opinion from a washing machine) and a roller ( machined from saline block VAZ 2108), screw diameter 1.9 m (help calculate the tail-practically)

31.01.2011, 21:29

You can start making the tail from the calculation: The length of the tail is not less than the radius of the propeller, and the plumage area is 10-15% of the swept surface of the propeller. And for further calculations, you will need to know the distance from the axis of the mast attachment to the plane parallel to the screw and the plane perpendicular to the screw. In other words, the coordinates of the screw attachment point relative to the mast axis.

01.02.2011, 13:39

Sergey, Here I sketched the dimensions of the VG mount.

01.02.2011, 21:58

Goga65, From the pictures you can see that you have the opportunity to move the king pin to the left. That is, increase the distance by 9cm. It's good. If your tail is already ready, you need to weigh it. In the place where the tail is attached, take it with your hand 1. And put the tip of the tail on the scales, number 2. And then I will quickly estimate everything.

01.02.2011, 22:17

Sergey, Not Seryoga, I’m unlikely to shift the kingpin, unless I cut it off and digest it, but I’ll weigh the tail tomorrow

01.02.2011, 22:27

And I tried to find my Bulgarian the other day, it wasn’t there. The winter version of the workshop is just a warehouse of things forgotten since the summer!

02.02.2011, 18:25

Sergey, Having weighed the tail as you said. -6 kg. + - 50g. (With the support of the hand, the weight changes)

02.02.2011, 23:13

The king pin will have to be cut off to your liking. We need a second corner. Further, at the same time, it may be necessary to transfer the attachment point of the kingpin, so that it would be possible to adjust the weight of the tail. And yet, indicate the distance where you plan to cling to the kingpin with your tail ...

03.02.2011, 11:52

Sergey, I won’t cut it yet (in the Czech this angle is somewhere around 5-7 degrees), can you calculate at what wind the drawdown will be? spinning in the wind)

03.02.2011, 17:05

03.02.2011, 17:54

Yes, I saw a video on YouTube, then there the screw turned clockwise, and the tail was on the right (looking at the screw), I read on the forum that for such an arrangement of the tail, the screw must turn counterclockwise ?! Which is correct, who can tell?

That's some bullshit.

03.02.2011, 19:01

baysun, Brad in what?

Alexander

03.02.2011, 20:47

Goga65, if the screw rotates clockwise (if you look at it from the front), then the withdrawal should be done to the left. This determines the position of the tail. The explanation here is very simple: during an emergency turn, the propeller begins to bend strongly due to gyroscopic forces (which for some reason are usually underestimated, but in vain! They are very significant), while there is a danger of the blade catching on the mast (if the blade or propeller hub is not rigid enough) . With the correct direction of the turn of the windmill when the tail is folded, the propeller should tend to tilt upwards, in any case, the precession force on the lower blade should have a direction not towards the mast, but away from it. This is what determines everything.

03.02.2011, 21:16

the screw should tend to tilt upwards, in any case, the precession force on the lower blade should have a direction not towards the mast, but away from it.
Alexander, can you be a little more specific. Let's leave the gyroscope for now, it's more clear here. But in this precession, not quite. After all, the rotation of the axis of rotation of our "top" occurs perpendicular to the axis of the mast, so if you look from the side of the propeller and it goes, say, to the right, then the bending loads on the blades located to the right of the mast should decrease, and those on the left should increase. That is, to experience an additional load from a turn due to these precession forces. But what about top and bottom? Explain please?

Alexander

03.02.2011, 22:00

Let's leave the gyroscope for now, it's more clear here. But in this precession, not quite.
So it's not clear.
Precession is a property of the gyroscope and cannot be separated from it. If the screw rotates clockwise (in this case it forms a gyroscope disk), then when you try to turn it to the right relative to the vertical axis, it will tend to tilt down. This is the most - that neither is - precession. Accordingly, when turning to the left, the propeller disk will want to tilt up. Are we looking at the screw from the front? I hope that the top from the bottom can somehow (although it's incredibly difficult, I understand ...) can be distinguished?
As for the bending loads, they do not decrease with any turns. They only increase. Because they are many times superior to the centrifugal and aerodynamic forces of the blades. And our task is to choose the direction of folding so that the screw cannot hook the mast.
This is easy to check on the simplest model: it is enough to take a thin tin disk and, putting it loosely on a knitting needle, set it in rotation. Rotating this disk in one direction or another and at the same time trying to turn it around vertically, you can see everything with your own eyes and, accordingly, understand it.

03.02.2011, 22:21

Alexander, What is in the pictures from: http://www.thebackshed.com/Windmill/Docs/Furling.asp - does the screw turn counterclockwise?

Alexander

03.02.2011, 22:26

There is no direction of rotation drawn, but should rotate counterclockwise.

03.02.2011, 22:33

Alexander, So I'm doing it wrong. I read and wrote down somewhere that it’s the other way around, and my Czech (but it works and the tail “plays”), and now the second Bulgarian, I didn’t weld the frame correctly - my blades are cut out for rotation by the hour. arrow, and screw threads.

Alexander

03.02.2011, 22:46

Goga65, Well, these are babies. They don't care. They may not be removed at all. But as soon as the windmill becomes large, this is where it begins ... Viktor Afanasyevich's windmill does everyone remember? Here, this effect manifested itself already twice: the first time, when the shovel touched the mast and was slightly damaged, and the second time, when the windmill collapsed with the blades flying off ...
I recommend experimenting with a tin drive, which I mentioned above. It's better than any theory.

03.02.2011, 22:58

Goga65, I will definitely check it out. A disk, even if made of plastic, in the center is a bolt with a nut, and all this is in a drill with adjustable speed. Should show something...

Alexander

03.02.2011, 23:18

Sergey, You don't even need a drill. Just thread a thin axis into the hole, and let the hole itself be free. Hand pushed in the right direction and you can observe all the effects.
And if you put on a drill, it is beneficial on an elastic suspension. Let's say, instead of an axle - a rigid spring, for example, from an old clamshell. A very visual demonstration device will turn out.

03.02.2011, 23:57

I already checked it: i_am_so_happy:... I confirm with left rotation and turn to the left, the disk approaches the conditional mast photo 1. With left rotation and turn to the right, the disk moves away from the conditional mast photo 2.:pardon:

04.02.2011, 03:48

Precession is a property of the gyroscope and cannot be separated from it. If the screw rotates clockwise (in this case it forms a gyroscope disk), then when you try to turn it to the right relative to the vertical axis, it will tend to tilt down. This is the most - that neither is - precession.

Damn, well, I have a windmill made incorrectly. :scratch_one-s_head:
As they say: do not take everything into account, mistakes cannot be avoided.
In the summer I do it, I move the tail to the other side, and the displacement of the screw to the other - everything is mirrored horizontally.

04.02.2011, 06:41

I would just like to clarify, turn to the right, if we look at the screw from the front, then the left part of the screw approaches, and the right part of the screw moves away - right? And then the relativity of rotation can be considered from different points and the right will turn into a left, but the direction of rotation will also change. Let me rephrase. When turning in the direction of rotation, the screw presses against the mast.

04.02.2011, 06:45

the side of the direction of rotation is also relative :)) ,
clockwise:
rotation of the upper part of the disk - to the right,
lower part of the disk - to the left,

On what part of the disk is the reference point taken?

04.02.2011, 06:55

not to take everything into account, mistakes cannot be avoided. If not for Alexander, we probably would not have known about this phenomenon for a long time.

04.02.2011, 07:42

When you screw a corkscrew into a bottle, we twist it clockwise. Is it right rotation or left rotation?
This is a right rotation, I mean to put all the points, and there was no ambiguous interpretation and conclusions;) there should be clarity everywhere so that there are no doubts about the correct understanding of the subject of discussion .... because. We live in a world where EVERYTHING is relative;)

04.02.2011, 08:17

there were no doubts about the correctness of understanding the subject of discussion .... because. we live in a world where EVERYTHING is relative. I just tried to describe it in clever words and, alas, nothing happened. Whatever it is left-right, and the mast can be brought from above, all motion processes are considered in space. Where there is a point, a line and a plane. In this case, we consider the position of moving points on a rotating disk relative to the fulcrum located on the axis of rotation of the disk, when a force is applied to the axis of rotation. Points on the disk located in the direction of force application tend to move away from the fulcrum, and approach from the opposite side. When a point moves along the direction of force application, it tends to move away from the support. And the points moving towards the applied force approach the support. In rewarded. I'll check in the evening. And now it's time to go to work.

04.02.2011, 09:29

No, guys, I think this is all complete nonsense.
If the blades tend to bend enough to hit the mast, then they are too frail for anyone.
As far as I know, according to the rules, the screw should look a little up from 3 to 5 radii. This removes the possibility of hitting the mast with the blades.
And where it will rotate is not important. No matter how you twist it, centrifugal forces will still try to leave the screw in the same plane. In a strong wind, the pressure on the propeller on the left and on the right is, in general, the same.

04.02.2011, 09:39

baysun, this is not nonsense, there is such a moment, and the blades from the pipe love to bend, so you need to try to take into account all the little things, no matter how small they may seem.

04.02.2011, 10:49

Didn't understand a damn thing! In the photo, Seryoga is a grinder, but she has no reverse rotation. I'm going to turn the drill myself!

04.02.2011, 11:21

I don’t know, maybe I’m wrong, only on large screws, I think, such troubles on the drum.
These are small screws that spin like crazy, with large ones everything is a little different. There, with the wind, such things, in my opinion, are not felt.
In principle, I again didn’t get into the hit, I argue on the example of my wooden propeller.
I have never seen a screw from a pipe live. Maybe something like that really matters.

04.02.2011, 11:52

Didn't understand a damn thing!
And why reverse, it is enough to turn the rotating disk to the left, then to the right.

Added after 43 seconds
on the example of his screw made of wood.
blades made of wood do not bend like that.

04.02.2011, 12:50

Quote: Posted by Goga65
Didn't understand a damn thing!
And why reverse, it is enough to turn the rotating disk to the left, then to the right. Well, it started with the direction in which the screw turns?
Here I cut out a circle from cardboard, inserted it into a drill through a spring and scrolled it, turning the drill left and right. -Indeed, when turning, the circle leans towards or away from the imaginary mast. As shown here: http://www.thebackshed.com/Windmill/Docs/Furling.asp and when the propeller is rotated clockwise, the propeller deviates from the mast, which means that I (and you Dima too) have the VG welded correctly!
My experiments allow me to disagree with Alexander.

04.02.2011, 13:07

Opinions are divided .... I need to check it myself :)

04.02.2011, 13:09

gda98, This will be the most correct solution!

04.02.2011, 13:18

Yes, I checked, everything is correct :)

Added after 2 minutes
Put the CD on the axis and checked. When rotating clockwise, when folding my windmill, the blades bend away from the mast, when the propeller returns to the wind, the blades approach the mast ... like that;)

Added after 2 minutes
no, on the contrary, it’s not right for me, my screw folds to the right and rotates clockwise

Added after 1 minute
in short, I’ll test it on a drill later, otherwise my experiment makes me doubt its purity ...

04.02.2011, 14:45

Here I took a picture of my VG in a gusty wind, it seems like the blade is moving away from the mast.

Alexander

04.02.2011, 18:58

Guys, are you confused? At the very beginning, I said that we are looking at the screw from the front. That is, we are in front of the windmill, with our backs to the wind. When holding a drill in your hands, you are behind the windmill. Therefore, while observing the rotation clockwise, we must understand that in fact it occurs counterclockwise. Dima is right. Everything is relative in this world. (... but this does not mean that something needs to be attributed, and something can be attributed later ...) Therefore, we must clearly agree on where we look at the screw from.
As for whether this should be taken into account or not, here is what can be said. For windmills with an adjustable pitch propeller, this does not need to be taken into account, for folding tails it is necessary. For the folding of the tail occurs in a highly extreme mode for the screw, and the gyroscopic forces are ten times higher than the centrifugal ones. Making a screw too hard means making it too heavy. And get even more power. Forces that break the swings of the blades and tend to bend the shaft of the wind turbine. If you make the screw elastic, then it will turn out to be lighter, but at the same time there is a danger of hooking on the mast. With all the consequences ... Therefore, all this fuss occurs around the direction of rotation of the propeller and the side where the windmill should fold during squalls.

04.02.2011, 20:09

As far as I know, according to the rules, the screw should look a little up from 3 to 5 radii. This removes the possibility of hitting the mast with the blades. And where it will rotate is not important. This eliminates the grazing of the blade from the force acting on the blade during the deceleration of the air flow, and it does not matter in which direction the propeller rotates.
No matter how you twist it, centrifugal forces will still try to leave the screw in the same plane. Thereby reducing bending.
In a strong wind, the pressure on the propeller on the left and on the right is, in general, the same. We are not considering the pressure on the propeller now. We want to understand what forces (except pressure and centrifugal) still act on the blade of a rotating propeller at the moment it is pulled out of the wind...

Added after 10 minutes
and when the propeller is rotated clockwise, the propeller deviates from the mast, which means that I (and you Dima too) have the VGs welded correctly! If you look at photo 4, it’s not clear, and you didn’t write in which direction the turn was made ...

Here I took a picture of my VG in a gusty wind, it seems like the blade is moving away from the mast. At such a distance from the mast, you are not threatened with touching, rather the blade will break.

Added after 20 minutes
For the folding of the tail occurs in a highly extreme mode for the screw, and the gyroscopic forces are ten times higher than the centrifugal ones. Making a screw too hard means making it too heavy. And get even more power. Forces that break the swings of the blades and tend to bend the shaft of the wind wheel. Respect to Alexander. I once asked Dima what diameter to make the propeller shaft? He said he read somewhere 1/80 of the turbine diameter. If you take 3m, then this is 37.5mm. It was then that I had a lot of questions like: Based on what did this figure come from? What does she take into account? If the weight of the turbine, then it is not clear at what distance it is from the first support. If the torque, then for a six-bladed one it is 2.5 times more than for a two-bladed one. But it is unlikely that anyone took into account the gyroscopic forces arising at the moment the wind wheel is pulled out from under the wind. And as Alexander noted, these forces are quite significant, and in places of stress concentration paired with torque, they can simply cut off the shaft.

Alexander

04.02.2011, 21:33

Based on what did this figure come from? What does she take into account?
This figure is somewhat excessive. Redundancy is taken in order not to bother with the calculation of strength for each specific case. If we follow this principle, then the strength will be quite sufficient, and in the case of a long shaft, its bending by a wind wheel will not lead to irreversible deformations. Unless, of course, the shaft is made of steel-3. Previously, different types of windmills were produced in Russia. At least - for one of them I managed to find data on the diameter of the main shaft bearing. It turned out to be 75 mm in diameter for an 8-meter multi-wing. (Then I found a drawing of his windhead and there I saw the diameter of the shaft itself. It had a little more than 80 mm). It should also be taken into account that the load on the shaft from the moment of the gyroscope in a low-speed multi-wing is significantly less than in a high-speed three-bladed one. By the way, Fateev also mentioned this in his book.
So what can be done on the recommendation of Dima and it will be fine.

04.02.2011, 22:08

It turned out to be 75 mm in diameter for an 8-meter multi-wing. (Then I found a drawing of its wind head and there I saw the diameter of the shaft itself. It had a little more than 80 mm). Surely this head was not taken out of the wind in the way that we are trying to figure it out.

Alexander

04.02.2011, 22:40

This is the way it was taken away. When the wind speed exceeds 8 m/s. Operating speed is only 25 - 35 rpm.

05.02.2011, 00:30

Here you are arguing, right or wrong. In my opinion, the point is not which side of the mast to place the propeller, but which tail. The fact that the plane of rotation of the propeller (read the blades) will bend either towards the mast or away from it when the propeller turns around the mast is obvious. Let the propeller under the wind always rotate around its axis in one direction, no matter which way. Let's say we placed the propeller so that the blades move away from the mast when it is pulled out of the wind by turning the propeller around the mast. BUT, when the wind weakens a little, the propeller again needs to be "introduced" into the wind, and it will now turn around the mast in the opposite direction with the SAME direction of rotation of the propeller itself, and, therefore, the blades will be pressed against the mast. The situation described can be repeated exactly the opposite, the essence of this will not change.

The propeller ALWAYS rotates in the same direction, and as it turns back and forth around the mast, the blades will either press against the mast or move away from it.

Thus, if we are talking about this phenomenon, then everything will ultimately (simplified) come down to calculating the bending of a cantilever beam, which is the blade. The bending moment will depend on the magnitude of the force acting on the length of the blade. This force is maximum at the tip of the blade and is zero at the axis of rotation of the propeller. It will depend on the mass of the blade, the angular velocity of rotation of the propeller, the elasticity of the material of the blade and the acceleration with which the propeller rotates around the mast.

So, in any case, you need to tilt the windhead a little up so as not to strike the blades on the mast. But how much it is enough to tilt - here you need to consider ...

05.02.2011, 00:39

BUT, when the wind weakens a little, the propeller again needs to be "introduced" into the wind, and it will now turn around the mast in the opposite direction with the SAME direction of rotation of the propeller itself, and, therefore, the blades will be pressed against the mast.

The key word in the quote above is the word - WEAKEN, which means that when leaving under the wind, the revolutions will be higher, and therefore the moment of forces will be greater than when the propeller returns to the wind, which means that the propeller will bend away from the mast when leaving more than when returning, it tends to touch the mast ....
nevertheless, Alexander is right in that it is necessary to correctly place the tail of the wind deflection system.

05.02.2011, 00:44

the key word in the quote above is the word - WEAKEN

All this is very conditional, because. in this case, it is necessary to take into account the moment of inertia of the propeller loaded by the generator ... I'm not saying that Alexander is wrong, it's just that, in my opinion, the significance of this phenomenon is somewhat exaggerated ...

05.02.2011, 00:46

The propeller ALWAYS rotates in the same direction, and as it turns back and forth around the mast, the blades will either press against the mast or move away from it. That's exactly right. But, when pulling out from under the wind, its rotational speed and turning speed are much higher than when it returns back.

05.02.2011, 00:52

But, when pulling out from under the wind, its rotational speed and turning speed are much higher than when it returns back.

How to say, how to say ... We take it out of the wind in order to reduce the speed, and we introduce it under the wind to increase the speed ... I don’t think that they (turns) will be so "drastically" different.

Added after 2 minutes
In general, it was about folding the tail ... :sorry:

05.02.2011, 00:53

the significance of this phenomenon is somewhat exaggerated ...
no, watch the video, how my propeller turns and what speed it develops, and its diameter is 2.5 meters;)
http://www.youtube.com/watch?v=3JQIf0adPDc&feature=player_embedded

But it returns to the wind already at a speed two times lower.

05.02.2011, 00:54

I'm interested in another question here, namely. The wind both blew in the forehead and blows, but the point of attachment of the screw, when turning, begins its1 movement, first almost perpendicular to the wind, and approaching 90 degrees, almost parallel. With all the ensuing consequences...

06.02.2011, 23:15

Something silenced everything.
Today I had a free minute at work and I decided to personally check what and how with this tail. Everything you see is made on potholders and any size can be changed in any direction. It's just that we, as always, first do and then we count. (Correctly Igor?: scratch_one-s_head:;)).
Photo 1. Collected the necessary blanks.
Photo 2. Welded a rotary knot.
Photo 3. Welded the generator mount, as it should be at an angle of 4 degrees.
Photo 4-5. Pivot in two planes.
Photo 6. I strengthened it a little, but it turned out quite flimsy.
Photo 7. It's like the long-awaited TAIL began to make ...
Photo 8. Gathered everything together, General view.
Photo 9. Front view.
Photo 10. Side view.
Photo 11. Top view.
Photo 12-13. As rightly noted, one should never forget about the restrictive emphasis. How many good mills have been destroyed because of this.
I look forward to your comments and wishes. :#

07.02.2011, 11:51

Sergey, Is this a model or a future working model? In photo 9, why did the tail in the initial state go to the right? It should be perpendicular to us.
And according to my measurements on this model, the screw should rotate counterclockwise.

07.02.2011, 12:40

Sergey, In photo 12, the upper stop is not needed, the tail is needed at the bottom.

08.02.2011, 04:57

I seem to be starting to understand a little. Surely each of us, once wanting to make a windmill with our own hands, began our journey with good old books and brochures that can now be easily viewed in our library. But the desire to get a lot of information and in a short period of time leads to superficial knowledge. Many little things just go unnoticed. Now on the subject of discussion in this topic. It is impossible to make a preliminary effort to start folding the tail without tilting the shin parallel to the plane of the wind wheel. It is this angle that determines the force of the wind at which the withdrawal from under the wind will begin. The angle along the axis of the windhead determines the strength of the wind at which the wind turbine will completely go into protection. On the second question. The figure clearly shows in which direction the blades are beveled and where the wind head is located. And finally, precession. I hope on the animation the spinning top rotates clockwise, that is, it has a right rotation.

09.02.2011, 18:09

There was a question about the axial pressure on the screw. I found three sources and for some reason different results are obtained in all. So where is the truth?

09.02.2011, 18:21

Sergey, If the memory is not beaten off, Vladimir, he also said it depends on the speed (filling).

09.02.2011, 18:32

LEX, but you also see that no one takes this into account. I think that all calculations are carried out taking into account the maximum flow deceleration. Let's just say, the maximum KIEV in some kind of wind. Therefore, it does not matter what turbine is worth ...

Added after 6 minutes
In photo 12, the upper stop is not needed, the tail is needed at the bottom. Just the opposite is true. The restriction is necessary when the tail is fully folded. So that the blades do not hit the tail ...

09.02.2011, 18:39

Sergey, I made a tablet based on the formulas from the book, Alexander gave these formulas to me.

Alexander

09.02.2011, 19:06

"Blade". Page 21, post 207...
.php?p=2092&postcount=207 Here everything was chewed in detail. What, how and why. It's amazing how quickly we forget. The formulas, according to which Dima made the plate, just take into account the coefficient of deceleration of the flow by the wind wheel when it works correctly. Everything else that the people offer is a very simplified calculation. The second picture in Sergey's message is how it will put pressure on a flat plywood solid disk. If you divide the force in the first picture by the one in the second, you get 0.879. And the load factor on the swept surface of the wind wheel is 0.888. Which is very close. Don't find? The calculation in the second picture is suitable for a multi-wing, because it has a huge fill factor and because of this, the load on the wind wheel is close to an equal-sized plywood disk. And the frontal pressure for the high-speed case, of course, is less. Do I need to explain further, or is everything already clear? :))

16.02.2011, 09:42

Started reading this thread. Good topic, much needed. And still want to understand all the details. Help guys ... Work when turning the head 90 degrees (Pi / 2) \u003d M * 1.57 Why 90 degrees? Where did it even come from? It’s just that theoretically we won’t be able to turn more than 90. And how much anyone needs, this is the second question. That's why there is resistance in this FURL formula = Tail Weight * Sin (Pivot angle in degrees) * Sin 45o.
Yes, it returns under its own weight, but I think that it returns late, but it is rejected by a small degree, I have somewhere around 3-5 degrees
gda98, What kind of degrees are these? If up, then everything is clear. And if against a reversal, then this is completely different ...
Work while lifting the tail = mgh m weight in kg g - 9.81 gravity h - height of the point at the center of gravity h = distance in meters from the center of the tail kingpin to the center of gravity * sina (sine of the kingpin angle) Here is the same incomprehensible place. Why the center of gravity? We're not lifting it at the center of gravity, are we? Well, why didn’t I take a dynamometer with me, I would have checked it a long time ago, everything would be experimental.
Sergey, I won’t cut it yet (in the Czech this angle is somewhere around 5-7 degrees), can you calculate at what wind the drawdown will be? - check, and then if we redo it, there will be both theory and practice. Now you can calculate a little. Tail 1.5m*6kg*0.342(sin20)*1(sin90)=3kg. It is with such an effort that the tail will resist. Move on. With what force do we need to press down on the screw in order to overcome these 3 kg on a lever of 0.06 m. 3/0.06=50kg. We look at the table and see that on a 1.9m propeller it will be with a wind of 18m / s. In total, if I understand everything correctly, before this wind it simply will not start to take shape. as a stabilizer and not a pull from under the wind, unfortunately they were justified! It's a shame, annoying, but the kingpin had to be digested. And do it not after the hurricane, but before the rise. For some reason I feel sorry for your work. But don't be upset. Let's make it better, stronger, more reliable...

16.02.2011, 12:16

Quote: Posted by Goga65
I didn’t leave the CZECH aside - first I tore off one and then the second blade (d = 1.5m), and the floating tail didn’t help - my assumptions that it works as a stabilizer and not pulling out of the wind unfortunately came true!
It's a shame, annoying, but the kingpin had to be digested. And do it not after the hurricane, but before the rise. For some reason I feel sorry for your work. But don't be upset. Let's make it better, stronger, more reliable...
In the Czech Republic, the king pin has an angle of inclination of 7 degrees in my opinion (I copied the tail from Valerin's autogenous)

17.02.2011, 11:53

Why 90deg? Where did it even come from?
http://alter-energo.ru/viewtopic.php?p=22966#22966

18.02.2011, 01:31

Valeriy, All this needs to be checked. And if white spots remain somewhere, you need to dig to the truth. There are a lot of places that I don't understand. For example, nowhere is the distance from the propeller attachment to the mast axis taken into account, and the distance of the tail position on the pivot to the same mast axis. But it's a two-arm lever. And it’s good if the shoulders are the same or close to each other, you can ignore it. And if they differ twice? With all the ensuing consequences. And there are many such places.

18.02.2011, 23:13

Greetings.

I downloaded the book Wind turbines and wind turbines on this wonderful forum and skimmed through it so far. Sergey, look at pages 191-192 and pp. 201-212, it seems to me that Fateev considered the issues that concern you there..php?p=430&postcount=6

Also, I drew attention to the message of Vladimir, where he says that the screws calculated according to the Zhukovsky scheme and those calculated according to the Sabinin scheme give different pressures. http://alter-energo.ru/viewtopic.php?p=11535#11535

19.02.2011, 12:41

serggrey, thanks for the help. Someone on the forum said that almost everything we have was researched and read back in the early 20th century. Vladimir wrote (The situation is worse if the screw is not calculated according to any of these theories... Then there is nowhere to go - you have to take its sweeps and integrate it.) Our calculations, even if they come down to understanding the ongoing processes, this is not bad.

10.03.2011, 18:50

I do not know where to write a question - I decided here.
Interested in how reliable the protection of a windmill from a hurricane with a folding tail system is?
All the same, I’m interested in whether it reliably protects a windmill with a propeller size of 3 meters and more in a big wind, for example, from 15 m.s and above?
If there are owners of such wind turbines, please respond please. Write what kind of wind your wind generators withstood?

10.03.2011, 23:12

I want to ask a question to the old. Has anyone tried this kind of protection system, or can tell about the pros and cons?

10.03.2011, 23:58

Makhno, Well, where's the catch? Like, not the entire tail is folded, but only the plumage?

11.03.2011, 00:07

LEX, there is no catch. soon I will also have a question about storm protection (well, I really don’t want a windmill that folds in half. Not beautiful). Here I am looking at options. this one is like nothing. Therefore, I want to know the pros and cons of such a design from competent people.

11.03.2011, 00:17

LEX, when only the plumage turns, not the whole tail.

11.03.2011, 00:41

So what is the scheme? it is not clear from the photo! I can also join the discussion. I didn’t understand anything, even the intention of what was presented ...

11.03.2011, 00:45

Another similar question. If you use not a rigid lever for the tail, but for example a polypropylene pipe? Will it move away from the wind even in light winds or will it still "keep its nose in the wind" :) And what kind of plumage should be put on it in this case ?

11.03.2011, 00:50

11.03.2011, 01:12

The system is normal. Who else calculated. I still don't understand how, even though I'm trying to overcome it.

11.03.2011, 01:20

Makhno, after reading, I understood the mechanics, the windmill itself is shifted to the side, when the force of the wind, the large screw begins to bend and the tail remains downwind, and the tail rotates relative to the screw (or rather, only the plumage, the tail rod itself is motionless), a brake drive is connected to this tail, such a system cannot be used on powerful windmills - the brake pads wear out quickly and braking disappears, up to 300-500W is possible, but you will probably have to change the pads once or twice a year.

11.03.2011, 01:29

11.03.2011, 01:53

11.03.2011, 15:37

If for the tail you use not a rigid lever, but for example a polypropylene pipe? Depending on which pipe and depending on which mill ...

11.03.2011, 16:18

11.03.2011, 20:47

Bosoiy

12.03.2011, 00:11

Bosoiy
With polypropylene, as with other thermosetting plastics, there can be problems in winter with severe frosts.

It happens on my veranda that it freezes in winter. But it has never burst. After all, the plastic is thick, due to this, and strength. Yes, and it will be convenient in installation.

12.03.2011, 00:11

All the same, I’m interested in whether it reliably protects a windmill with a propeller size of 3 meters and more in a big wind, for example, from 15 m.s and above? Previously, different types of windmills were produced in Russia. At least - for one of them I managed to find data on the diameter of the main shaft bearing. It turned out to be 75 mm in diameter for an 8-meter multi-wing. (Then I found a drawing of his windhead and there I saw the diameter of the shaft itself. It had a little more than 80 mm).
Surely this head was not taken away from under the wind in the way that we are trying to figure it out.
This is the way it was taken away. When the wind speed exceeds 8 m/s. Working speed is only 25 - 35 rpm. I hope I answered;) ...

12.03.2011, 09:05

It happens on my veranda that it freezes in winter.:bye:

This is without load, but how will it behave under load, and even after icing?

15.03.2011, 12:05

How is it without load? There are simply two types of pipe expansion. 1.-Linear. 2. Radial. In my case, the second one.

16.03.2011, 11:16

Good afternoon! Dima thank you very much for your help. You helped me a lot. A small 500 watt generator works and charges 2 batteries of 60 Ah connected in series. And it also heats the water if the wind is more than 6 m / s. It will be warm, I'll redo the blades, then everything will be fine. Please tell me you need to make a tail to fold? Thank you.

16.03.2011, 12:21

Do you need to make a tail to fold?
for a 500W windmill is already needed.

16.03.2011, 17:33

Thanks Dima. So it needs to be done.

22.04.2011, 06:39

I found a folding tail excel, it has not been tested, whoever wants to check it, check it and ask for the results, if it thinks correctly, then put it in the library.

22.04.2011, 10:25

I liked Evgeny Boyko's sign more

22.04.2011, 10:29

Found a folding tail excel
Dim, my tail is calculated on it - everything is clear !!!

19.05.2011, 10:10

19.05.2011, 10:22

19.05.2011, 10:34

gda98, Thanks Dima. Not in a hurry yet. Now I'll take care of the blades.

22.05.2011, 15:31

I read everything from beginning to end and so nothing concrete was found. I tried to look at the tables for the calculation, you need a password there. From what to count? And what data is needed to calculate the folding tail. I want to do everything again.

22.05.2011, 17:41

Pavel, what's the password?

22.05.2011, 19:47

gda98, There is a cross on the left, I click on it and it opens: You cannot use this command on a protected sheet (Unprotect sheet (Service)). When I open it, a password box pops up.

22.05.2011, 20:27

Pavel, which table exactly? There are several of them here.

22.05.2011, 20:30

gda98, Here on this page at the end I do not know which one suits me?

22.05.2011, 20:45

Pavel, you do not need to click the cross in the yellow fields, enter your data and get the result of the calculations in the blue fields.

22.05.2011, 21:38

gda98 Thank you. Let's try.

24.05.2011, 19:38

gda98, Dima does not come out. It's okay. I have the rotation of the blades to the left, this is so that the nut does not unscrew. So which way should the tail turn? And if you put in the middle or is it impossible?

24.05.2011, 21:40

I have the rotation of the blades to the left, this is so that the nut does not unscrew.
If you look at the screw, then it turns clockwise for me and the nut with the "correct" thread does not unscrew.

24.05.2011, 22:03

Goga65, This is just for reliability. And probably there is no difference in which direction it rotates.

26.05.2011, 21:01

Turned the sleeve for the tail on the bearings. How is the length of the tail and its dimensions determined?

28.05.2011, 12:07

About protection with a "tail" (for Pasha): from the info of NO, I did something like this:
tail length=wind wheel diameter
tail area=10-15% of the wind turbine area
tilt angles "copied" from Valera (http://website/showthread.php?t=28&page=7)
Here is more info on the topic: http://evgenb.mylivepage.ru/page/Calculation_of_tail_empennage

28.05.2011, 14:55

Goga65 Thank you. Let's read.

28.05.2011, 15:36

Doesn't the length of the tail lever depend on the distance between the screw and the pivot point?

05.06.2011, 10:28

I have new questions about the turntable - I noticed that some people put the generators on the turntable at an angle of 4-5 degrees (vertically). What for?
Or the second question - from the center horizontally you need a generator or a tail. I'm talking about wind protection.

05.06.2011, 11:54

noticed that some put the generators on the swivel at an angle of 4-5 degrees (vertically). What for?
so that the tips of the blades are further from the mast and do not touch it.

05.06.2011, 12:00

gda98, but then we lose a few percent of power ..?!

05.06.2011, 12:14

put the generators on the rotary assembly at an angle of 4-5 degrees (vertically)
So that the blade does not touch the mast in strong winds.

From the center horizontally you need a generator or tail. I'm talking about wind protection.
both.

Added after 3 minutes
but then we lose a few percent of the power ..?!
I deflected up to 15 (albeit up when I adjusted the slip), and did not notice a loss of power.

05.06.2011, 12:31

but then we lose a few percent of the power ..?!
less than a percent is lost.

06.06.2011, 19:27

It’s clear about the tips of the blades and the mast. But there is still no clarity with the calculation of the tail.
.gif Tail calculation test..php?attachmentid=2742&d=1306566465) - when both the generator and the tail are shifted relative to the center - what value should be inserted into the line (Offset)?
Judging by the figure, offset is the offset from the center of the wind wheel to the center of the mast, and logically, this is the sum of the offsets of the tail and the wind wheel from the center of the mast.

06.06.2011, 20:41

06.06.2011, 21:48

In general, offset is translated as compensation.

Offset translates as displacement. Compensation is the second value.
I can give you about ten more translation values, but how will this help answer the question?

06.06.2011, 22:26

logically, this is the sum of the displacements of the tail and the wind wheel from the center of the mast.
No DIP, it's a turbine offset. It, together with the force of pressure on the propeller, determines the moment of the turbine, which the tail must resist with its moment.

06.06.2011, 23:14

Sergey, do I understand correctly that we insert the distance of the turbine offset from the center into the table, and when assembling the windmill, we spread the turbine and tail to this distance?
Sanya77, did you talk about this compensation?

07.06.2011, 03:10

DIP, about we spread the turbine and the tail to this distance, I do not agree. But that's just my personal opinion. I'll try to substantiate it. Yes, due to displacement, the turbine has a lever relative to the axis of rotation and we get a moment of force that tries to turn the table. On the other hand, we have an oblique kingpin with a tail, which should compensate for this moment and try to prevent the rotation of our table. But the force with which he will do this is his weight and it will act on the pivot. The kingpin, having an inclination, will put the projection of this force on the plane of the table, and on the lever for applying this force from the axis of rotation, we get the moment of the tail. That is, in my concept, it does not really matter where the kingpin is located. It is important at what distance from the axis of rotation. But I want to reiterate that this is just my opinion...

07.06.2011, 10:44

Again it doesn't fit. Let's look at the picture.
The turbine aims to turn the turntable using Lever1.
To balance, we put the tail with lever 2 or 3. Changing the location of the tail entails a change in its weight. We return to the table - what is offset?

07.06.2011, 11:38

I also can't figure out how to deal with this tail? Need to start doing and just don't know where to start? Lots of odd sizes. Where to get them is also not clear? For example tail dimensions (length width)? How far should the tail be from the head?

07.06.2011, 11:49

07.06.2011, 12:03

We have - air density = 1.29 kg / m ^ 3. Tail area \u003d X m ^ 2,
Wind speed \u003d U m / s ..
Tail arm length =Z m.
How to calculate the pressure on the pivot point from all this - for example, with one meter of lever and with two? Also, the question is how does the pressure on the rotary assembly of the propeller lever depend on KIEV? And most importantly, I just can’t understand .. Why should the generator be displaced relative to the rotary assembly? And how will the length of the bias lever work in our favor?

07.06.2011, 12:20

DIP, as for me, because the tail lever is what I marked in green. And it depends on the distance of the tail attachment point from the axis of rotation.
I am adding a new dot to the drawing. Section A is equal to section B.
Those. the attachment point is removed from the axis of rotation by the same distance. I don't think we will get the same effect when attaching the tail to the ends of the segments.

07.06.2011, 14:49

And I think it's the same. If in both cases the kingpin is tilted back, this table will stand in one place.

Added after 12 minutes
And most importantly, I just can’t understand .. Why should the generator be displaced relative to the rotary node? And how will the length of the bias lever work in our favor? Well, you give a brother: scratch_one-s_head:...
After all, with a tail, you can not only direct the propeller into the wind, but you can also take it away from under the wind. When it exceeds some speed of course. And earlier it’s not necessary, there the propeller should look at the wind.: hi:

07.06.2011, 15:01

Well, you give a brother: scratch_one-s_head:...
Let's say ... But unless the generator is not displaced, then the tail will not add up? Or if the generator is displaced, then the folding tail should not be done?

07.06.2011, 15:06

Need to start doing and just don't know where to start? Lots of odd sizes. Where to get them is also not clear? For example tail dimensions (length width)? At what distance should the tail be removed from the head?.php?t=221 Everything from what I found there:yes:. In general, it is generally accepted that the tail area should be 10-15% of the area measured by the propeller, and the length from the mast up to the diameter of the propeller. Although this should be treated differently. For example, I piled everything together, and then just started measuring it. :))

07.06.2011, 15:25

But unless the generator is not displaced, then the tail will not add up? And what kind of business does he have to develop ...
Or if the generator is displaced, then the folding tail is not necessary? I hope this schematic will explain how this system works.

07.06.2011, 15:29

Sergey, you are right. Spread the vectors, it turns out the dependence on the removal of the attachment point from the axis of rotation along a straight line perpendicular to the turbine.
Understood this. Now it's the turn for the blades :)

07.06.2011, 17:28

Sergey, thank you very much. I have already read all this more than once, but there is nothing concrete. Today they brought the pipe, I will make the blades and then we will start everything in order. My mast is 14 meters high.

07.06.2011, 19:02

I have already read all this more than once, but there is nothing concrete. So you still need to check it yourself: pardon:...
I've checked and with the left rotation of the screw, the generator is located to the right of the mast. Although when I applied 20kg to the blade at a distance of 0.75R, there were 15 centimeters left to the mast. Well, what kind of precession do you need to have in order to bend the blade like that. Although this effect is present. Gyroscopic forces are a completely different matter, you need to be careful with them.
Here I am tormented by vague doubts and I want to voice them.
With a swept area of 4 sq.m, the tail area turned out to be 0.4 sq.m. The length from the attachment axis is 1.6m + 0.3m to the mast axis. The weight of the tail is 4.2kg and the weight at the tip is 2.6kg. In principle, everything is fine and I grab the king pin at an angle of 20 degrees. But as long as I watched the whole thing, I never saw that the propeller tried to turn away from the wind. Although, compared to Goga, the screw is 2 times larger in area, it is 2 times further away from the mast, and the tail is 2,3 times lighter. So I thought that he should start moving away from the wind much earlier, and if you need to be rude, then it's much easier, just attached some kind of piece of iron to the tail and that's it. But as you can see, it wasn't there. Now you have to either lighten the tail, or reduce the inclination of the kingpin. This is how we live:unknw::sorry:...

07.06.2011, 20:27

So I thought that he should start moving away from the wind much earlier,
For me (for a Czech), the tail begins to lead away even with a stock screw !?

11.06.2011, 00:01

11.06.2011, 02:33

Here's what I found on my computer. Once subtracted and preserved.
The calculation of the tail with an inclined kingpin made by Vladimir Kotlyar...

I also wag my tail. I just can’t figure out what speed to take for the flow around the stabilizer. It turns out that 67% ??

11.06.2011, 03:57

I also wag my tail. I can’t get it in any way, the same toil and I can’t get it. But just the flow rate near the tail worries me less than the moment of the turbine. I'll explain why. Up to 0.5R is guaranteed, there is no such braking, and the tail is located approximately in this place. But this is not the main thing. By and large: The tail is larger, the lever is longer, it will not steer worse. But as for the moment of the turbine, the picture is not very good. The calculated deceleration of the flow, and hence the pressure on the screw, occurs when the screw is nominally loaded. So it turns out that an underloaded propeller in the wind will continue to unwind and will not go into defense. And God forbid, the load disappears, there will be no braking at all. Am I speaking correctly?

11.06.2011, 04:42

So it turns out that an underloaded propeller in the wind will continue to unwind and will not go into defense. And God forbid, the load disappears, there will be no braking at all. Am I speaking correctly?

Not right. If you do not remove the moment from the wheel, this does not mean at all that the axial force will disappear. Nothing is fed into the rotor of the autogyro and nothing is taken away. And at the same time, the resistance of the rotor is even greater than that of a disk with a swept surface diameter.

I have a tail in general nonsense turns out. It seems that the rotors of most windmills, in principle, are at an angle to the flow. The tail begins to work effectively only when leaving the wind shadow.

11.06.2011, 12:21

The calculated deceleration of the flow, and hence the pressure on the screw, occurs when the screw is nominally loaded. So it turns out that an underloaded propeller in the wind will continue to unwind and will not go into defense. And God forbid, the load disappears, there will be no braking at all. Am I speaking correctly?

On the contrary, if the screw is released without load and allowed to spin, then the axial force will increase compared to the nominal value, and just it will go into protection. and if you overload it, then it will allow more wind to pass through and the axial force will be less. So in this regard, physics works for us.

Gda98 wrote somewhere about his experiments either with a load or with the excitation of a generator, from those experiments it becomes clear how an overloaded and underloaded propeller behaves.

11.06.2011, 12:43

So in this regard, physics works for us. Well, at least something works for us. And then I already started to think, well, why didn’t I do it with a side shoulder blade? It doesn't matter if it's standing or spinning. And I don't think it's that hard to make...

It looks like the rotors of most wind turbines are in principle at an angle to the flow. You mean, like in position 3?

11.06.2011, 14:32

I mean, like in position 3?

No, these drawings are pure abstraction. The weather vane with a moment will stand along the wind only if it is welded to the mast.

Added after 2 minutes
On the contrary, if the screw is released without load and allowed to spin, then the axial force will increase compared to the nominal value, and just it will go into protection. and if you overload it, then it will allow more wind to pass through and the axial force will be less. So in this regard, physics works for us ..

Yes it is. Without torque from the generator, the revolutions will increase until the angle of attack becomes 1-1.5 degrees, which corresponds to the autorotation mode. By the way, from this angle, you can determine the speed of the separation.

11.06.2011, 22:33

Without a moment from the generator, the revolutions will increase until the angle of attack becomes 1-1.5 degrees, It would be nice, but the angle is constant.

A weather vane with a moment will stand along the wind only if it is welded to the mast. Why? I did it like this. Initially asked him some angle.

11.06.2011, 23:02

How to make a tail.?! I read and I don't understand. Is it necessary to bring him out from under the shadow? And this shnyaga, that it is necessary to weld it to the mast, what is it for?

11.06.2011, 23:33

Bosoiy, read more carefully. Ilya MGU is right. If a moment acts on the tail, it will never become along the wind because it will need to resist this moment. And the smaller this moment and the stronger the wind, the smaller the angle between the wind and the tail. But he will still...

Is it necessary to bring him out from under the shadow? Why? Everything is calculated. I'd rather say this. In the shade, you need 0.5 sq.m on some kind of lever for confident taxiing, and 0.3 sq.m without a shade. on the same lever.

11.06.2011, 23:43

Sergey, what moment acting on the tail does not allow the rotor to stand perpendicular to the wind?

12.06.2011, 00:14

If we take this position as the starting position, then only some pressure will appear on the turbine, the tail will immediately go to the side trying to compensate for this moment. But the turbine will already be at some angle to the wind, and not perpendicular. How far the tail goes to the side depends on its area, the length of the lever and the aerodynamic quality.

12.06.2011, 00:22

the tail will immediately go to the side
In which?

12.06.2011, 00:54

Because the turbine is displaced.

12.06.2011, 01:20

Why move it then?

Added after 4 minutes
And it seems in the figure that the larger arm of the turbine should bend the tail upwards relative to itself ...

12.06.2011, 01:46

Have you read this article? http://translate.google.ru/translate?js=n&prev=_t&hl=ru&ie=UTF-8&layout=2&eotf=1&sl=en&tl=ru&u=http%3A%2F%2Fwww.thebackshed.com%2FWindmill%2FDo cs%2FFurling .asp Since it actually began this topic. And there are such pictures. And now think for yourself, why shift. Tomorrow on the carpet with an explanation why you started everything like that: yes:...

12.06.2011, 02:08

It always seemed to me that a screw without a lever relative to the mast itself would look for the path of least resistance to the wind flow. After all, in the absence of a tail, even if you want it, even if you don’t want it, it will become parallel to the direction of the wind! And if we already have a certain moment, then why complicate the whole structure by adding another lever, which is not clear how to calculate it?

12.06.2011, 02:30

That's right, it will search, and it will become exactly behind the mast, but not parallel, but perpendicular to the wind - it will turn out to be a leeward version.

If the option is windward, then you need a tail.
if the windward propeller needs to be moved out of the wind, then the tail should fold.
For the tail to form, offset is needed.

Added after 1 minute
.... adding another lever, which is not clear how to calculate?

We consider the balance of forces and moments, we carefully beat everything - flies in one direction, cutlets - in the other.

12.06.2011, 05:46

We consider the balance of forces and moments, we carefully beat everything - flies in one direction, cutlets - in the other.
Class petruha256, otherwise you write to Bosom, but he does the same thing. "Why shift?" and that's it :)

12.06.2011, 09:43

No, well, I'm not completely stupid! :) Chewed, now I understand. :)) Thank you! :)

Added after 10 minutes
petruha256, let's say the screw is 2m. In the original, a bad translation and much remained incomprehensible to me. How to calculate the lever for its displacement?

12.06.2011, 12:04

This topic actually started with her.
My tail of the first Czech is arranged as in the picture (but without calculation), the rotation of the screw is clockwise (looking at the screw)

12.06.2011, 13:26

Quote:
Message from Ilya MSU
Without torque from the generator, the revolutions will increase until the angle of attack becomes 1-1.5 degrees,
It would be nice, but the angle is constant.

The angle of attack during the run will change not due to the rotation of the blades, but due to the fact that the circumferential speed will increase, i.e. Essentially, speed.

12.06.2011, 14:40

petruha256, let's say the screw is 2m. In the original, a bad translation and much remained incomprehensible to me. How to calculate the lever for its displacement?

Without getting into the jungle like this.

(1) Fa*x*pi/2=m*g*l*sin(a).

Fa - axial force on the screw.
according to Sabinin (2) Fa=1.172*pi*D^2/4*1.19/2*V^2
according to Zhukovsky (2.1) Fa=0.888*pi*D^2/4*1.19/2*V^2,
where D is the diameter of the wind wheel, V is the wind speed;

X - desired offset (offset);
m is the mass of the tail;
g - free fall acceleration;
l - distance from the kingpin to the center of gravity of the tail;
a - kingpin angle.

Let's say - a screw of 2 m, wind speed at which the tail should fold = 10 m / s
we consider according to Zhukovsky Fa \u003d 0.888 * 3.1415 * 2^2 / 4 * 1.19 / 2 * 10^2 \u003d 165N

Tail mass = 5 kg,
distance from the kingpin to the center of gravity of the tail = 2m,
kingpin angle =20 degrees

X=5*9.81*2*sin(20)/165/3.1415*2=0.129 m.

12.06.2011, 16:07

The axial force on the screw does not depend on its KIEV?

Added after 15 minutes
The tail wing area is also not visible. But a lot should also depend on its shape ..

12.06.2011, 16:10

Depends, but not much. If the screw is loaded to the maximum possible KIEV of this screw, then these formulas can be used.
If the screw is underloaded, the axial force coefficient increases. In general, without load, it will grow to 1 according to Zhukovsky and somewhere up to 1.3-1.35 according to Sabinin.
In general - formulas for an ideal propeller.

Added after 1 minute
The wing area of the tail is from another opera - from the one that should provide taxiing with the wind and keep the tail in the right direction, and not at all from the one that should provide folding for protection from the hurricane.

12.06.2011, 16:25

petruha256, thanks for the explanation :), we will use it. :)

12.06.2011, 22:04

petruha256, Thank you too. A little like it becomes clear. I have a propeller with a diameter of two meters, an offset of 0.129 m, a tail weight of 5 kg, and a kingpin angle of 20 degrees. Did I understand you correctly? It is still not clear what should be the area of the tail? And what if right rotation means to shift to the left, and left means to shift to the right?

12.06.2011, 22:14

Pavel, it’s not clear why you need to make the distance from the king pin to the center of gravity of the tail 2 m.

12.06.2011, 22:36

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