Protection of a homemade windmill (wind generator) from strong winds. Wind water aerators Swivel and slip ring

Wind Water Aerators

I decided to post my developments as a separate topic.
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 those who are interested to discuss the constructive parts. Maybe together we will find more effective solutions.
An Internet search did not give any results either 3 years ago or now. Now all around are links to my videos on YouTube
To be continued...

Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

So how it all started:
Having bought a plot with a reservoir, but without electricity, I faced the problem of winter frost. Total.
I started looking in the internet.
The idea of \u200b\u200ban electric wind generator was dropped immediately. In the field he will be stolen. Together with electrical water aeration equipment.
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 possible tips from members of the forum.
Along the way, I studied all possible types of wind turbine blades. I learned a lot about the strength of the wind, about the disproportionality of its strength with an increase in speed, its instability and so on.
The most efficient in terms of energy removal from the wind turned out to be the most difficult to implement technically.
The simplest and most forgiving execution flaws remained the Savonius rotor and the multi-blade (chamomile).
The "camomile" was tempted by the possibility of using small winds. But at the same time, the requirements for increased strength, since in hurricane winds it breaks down.
I tried to make a small chamomile, only 1 meter in diameter. Unfortunately, there is no photo of that work left. Of course, it did not work out qualitatively on the knee. But it was spinning. In reality, I saw that there is energy in the air.
But with the camomile, the rest turned out to be even more difficult to implement.
It was necessary to make a reference point 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 turning. And plus the fight against hurricane breakdowns. It turned out to be quite an expensive pleasure.
I began to examine the Savonius rotor.
It turned out that it is the most ineffective in terms of wind energy extraction (efficiency).
But it turned out to be the easiest to execute. His performance forgave many flaws in performance.

To be continued...

Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

The first Savonius windmill that I made was also not captured for history.
As I thought at the beginning, we need to make it as easy as possible so that it starts with minimal wind.
Therefore, a meter M6 hairpin was taken, and two halves of a transparent plastic bottle were put on it. And there were two such blades. Above is a bearing, below is a sheet of tin that drove water.
The construction worked. It spun in almost complete calm. Even the face is not felt, about it is spinning.
But there was very little energy. The wind collection area is too small. And at night, in complete calm, she froze.
I went further. I had a bunch of buckets for 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 wind turbines, and a description. Therefore, I will not repeat myself.
There were 8 such wind turbines per 10-hectare canal. She seemed to be working. But there was a big minus - they were constantly freezing 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 pestilence passed, there were a great many corpses. Maybe the pestilence was not total.
But on these windmills I understood one thing - how to position the blades relative to each other. They had to be not adjacent to the axis of the windmill, but overlapping each other. Only they worked much better.
For the next winter, I decided to radically change everything. For I already had an idea more or less what I needed to do.
The first is to increase the power.
The second is to make an antifreeze so that it does not freeze at night and the wind turbine would work autonomously and without full stops.
The third is to make the structure rigid, that is, so that the windmill does not dangle on the upper bearing, but stands rigidly fixed.
Fourth, instead of a can for a water propeller, 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. I made a bucket from above at the beginning, I was afraid that he would not start from the third point. I will say right away that it was a delusion, it was removed when the windmill was being repaired.

Antifreeze was made. (all on video)
http://www.youtube.com/watch?v\u003dRYbgkM5LUCA
The windmill is fixed on a frame made of stakes both from below and from above.
For the propeller, the machine's radiator fan blades were used.
At first, they put, like small bucket windmills, on two stakes, without spacers. Subsequently, the hurricane put the entire structure in the water. then I had to cut everything down after freezing.
So, having made a windmill, we went to put it. It was windy. Having installed it, we were amazed at the energy. The water was literally boiling.
Arriving a day later, instead of a 40 cm hole under the windmill, there was a hole of 3 meters. The ice at the time of installation of the windmill was 42 cm. It all washed away.
I can say that this first windmill was repaired only once - when it was put down due to the lack of braces. Having installed the braces, they did not do anything until spring. Once it was a hole in a very frosty and windless night. When we arrived urtom, we saw a frozen windmill. The ice was more than 5 cm. It was 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 several weeks before the whole pond.
The result was a pestilence, but not strong. A lot of live fish were seen. The wind turbine worked, and very well. It was clear that there was life in the pond.
It made me happy. This showed that the idea worked.
Yes, here is the spring video. I stepped on the lower bar and it broke. They left it that way, and then the wind threw the windmill on its side.
http://www.youtube.com/watch?v\u003drdgi9v5968U
Pushed and worked like that.
http://www.youtube.com/watch?v\u003dkzFHXMnKItg
By the way, the windmill worked then almost all summer. During this time, he passed the strength test. Then he rubbed the plates holding the bearing, and he fell into the water.

To be continued.

Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

The next winter, the fallen windmill was taken out of the thinnest ice, sorted out, and immediately put. I have already begun the manufacture of another windmill based on past experience. Larger.
What was planned:
1. It was decided to completely frame. This gave a 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 "blind spot".
3. Plus it was conceived because of the increase in power to make a reduction to increase the propeller speed.
4. There was an idea to make the lateral movement of water. It turned out that in the previous version the propeller enriched water quite locally near the windmill. Having forced the windmill to draw fresh water all the time, more oxygen was absorbed by the water, and it should also have been good to release gas from harmful gases.
5. Small modification of the anti-freeze agent. In the previous version, a sleeve made of polyurethane was made under the oil seal. 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 out of stainless steel. Plus, polyurethane changed its shape greatly from heat and frost, which also influenced the geometry.
What happened:
1. Done. Fully justified the idea.
2. Done. Also fully justified itself. Plus, due to the increase in height and the combination of energy removal, such a design turned out to be 30-50 percent faster than single-blade wind turbines.
3. It didn't work out. I tried to make a reduction through bicycle stars. And there they needed precise turning work, "on the knee" did not work, constantly throwing off the chain. The idea was not implemented.
4. It was done. The idea paid off. Subsequently, this part is disassembled and done in a different way. 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 was very justified. The resistance has dropped dramatically.

To be continued...

Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

So, in the year when the frame windmill was made, the weather was not good. The ice rose, but 5-7 cm, and the sweat covered with snow. It was loose, it was scary to go out. I put 5 cm of ice each. very uncomfortable. The edge of the hole, it breaks off, you can't come close. I swam up to my waist 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. And in the end, it shifted to the side, and went to the side of the channel.
And so the windmill stood up to strong ice, when it was possible to approach it for work. And a third windmill was set up on the strong ice.
An oblong wormwood from a windmill is visible. It was so blurred by the side propeller.

The windmill laid down on good ice and tried to turn in order to direct the stream exactly along the canal. Due to the careless movement, the windmill fell loose, and the frame was slightly bent. Imperceptibly, but it was evident that he was wiping somewhere on the landing nests. Then they found this place, and removed the rubbing place. But the fact remains: you have to be very careful.
But still the windmill could not be turned. So he left it.
Then it was decided to make the lateral movement in a different way. Take the cable from the speedometer and transfer the torsional force through it directly to the sideways propeller.

To be continued...

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Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

Registration: 06.10.08 Messages: 16.642 Thanks: 18.507

In the course of using / testing the windmill, all sorts of "sores" got out.
For example, the anti-freeze agent first made a chair for the oil seal made of polypropylene. it turned out that in the cold it changes its geometry, water is slowly being collected into the anti-freezing agent and one fine morning you see a windmill standing up with a stake. We decided to remove the antifreeze, order a stainless steel sleeve from the turner and replace it.
This opened the eyes to a new design flaw. It was necessary to make the antifreeze detachable from the axis, without removing the windmill itself. In the beginning it was made from a common hairpin. I had to cut the hairpin with a hacksaw, and then connect it with a long marriage nut.
But having cut even the axle, it was not possible to remove the antifreeze without removing (laying on the ice) of the windmill frame 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 seat, but the propeller did not give.
I had to lay down and disassemble it in detail (tilt it over the hole, where more than one dropped key drowned), but the idea of \u200b\u200bhow to get around this was born in my head.
When they put it down, I decided to drain the water sideways not with tin, as in the video, but through a speedometer cable. The last video shows how. It turned out that it was not possible to clamp the cable well "on the knee".
As a result, the tin was also removed (or rather, knocked down, since it was being welded), and it was impossible to put it back on the ice, and it did not work with the cable. They did it several times, all to no avail.
And so the windmill worked until spring.
In the spring, with a gale wind, the windmill broke. I must say that the spring winds broke one of three and break every spring. In different places. This time, the frame and the entire structure resisted, but the blades did not. One blade was torn off, it jammed in the frame, then the lower blade was rolled by the wind along the hairpin, on the thread it drove to the very bottom and jammed. Or maybe vice versa, I don't know. But the result was as follows. But this is already in the spring, the ice was decrepit, the hole was huge. The winter has already passed.
I left the windmill like that. He stood all year until this winter.
This year, this pond was lowered and left to freeze. But in my main canal, reclamation has been brought together, water constantly flows there, and does not freeze. Filmed in the middle of winter, on ice 5 cm, and then the partner failed.
Having removed, we saw another constructive flaw: it was necessary to cut everything again in order to remove the blades for repair.
This has been fixed. Now each part from each compartment of the frame is removed autonomously, without disassembling adjacent parts.
I noticed an interesting thing: where the caps were over the bearing, the bearing seemed to have just been installed - it was covered in oil and works like new. Where there was no cap, the condition of the bearing was poor. Now we cover all the bearings with a lid and pass the axle hole with silicone

All wind turbines were moved to 6 hectares.
But 3 pieces per 6 hectares is very little. 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 Thanks: 18.507

Having rearranged the windmills, I decided to make antifreeze out of a metal pipe, with a turning machine for bearings. The fact is that the first version with a plastic pipe did not give accurate alignment, which also gave extra resistance when the anti-freezer was scrolling.
The precise anti-freezing agent assembled on a lathe made me happy with its symmetry. The resistance has dropped, and very significantly. He was almost gone. Even in the smallest wind, the wind turbine did not stop from the action of the clamped anti-freeze. This metal pipe has been painted black to help the sun warm it.
But then another factor appeared, which I did not take into account. The metal pipe was much more thermally conductive than plastic, and in the calm, it froze through the pipe three times deeper than the ice itself grew over a windless night. Because of this, even though the anti-freeze was installed 10 cm below the water level, it froze. The cold went down the pipe into the depths, froze the pipe, and from below grabbed the hairpin. Through the transparent ice, one could see how in the depths the pipe was all covered with needles of frozen ice. Handsomely. But it is harmful.
On one windmill, where the anti-freeze was lowered deeper, it did not freeze there. Now I'm thinking about how to do it better - either shove it into the foam, or lower the anti-freeze pipe deeper.
I haven't decided yet. there were winds at night, so while they work, let them work.
I decided to push the water sideways. To do this, the turner ordered the pressing of the cable into the hairpin. Shown in the last video.
We made three of these cables.
The first time the propeller was mounted on a hairpin. But when rotating, the windmill collected the cable in a heap, twisted it. But it worked, the movement of the water was strong.
The next day, we decided to fix this contraction, and made a lower subframe (one of these days I will try to make a video), where everything was rigidly fixed in the frame. And the second was made on a plate to be put on a single-blade windmill. We arrived, and the first cable was broken. They blamed the installation for a bad thing, which twisted him.
Everything was assembled and installed. Everything worked just fine.
That 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 obviously problematic.
Now I will return to the original idea, when the propeller is on the 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.
Propeller force in Newtons (P) \u003d 0.5 * 1.23 * propeller area in square meters * wind speed squared.
The moment (M) is applied to the center of rotation of the windhead in Nm \u003d P * distance from the center of rotation to the center of the propeller in meters (displacement 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 \u003d mgh
m weight in kg
g - 9.81 gravity
h - lifting height of a point in the center of gravity
h \u003d distance in meters from the center of the tail kingpin to the center of gravity * sina (sine of the kingpin angle)
Although I don't really understand why not tangent, although they are close

11.08.2010, 23:34

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

Added after 4 minutes
Thank you for the formulas, I will make a plate 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 a spring, because the folded quost does not want to maintain the speed of the windmill and expand to the desired angle when it could be used, the 10A ammeter for mean goes off scale during a hurricane, the tail folds, the current drops to zero then again and this happens cyclically during a hurricane, but you can do it always 10A gave out :)

11.08.2010, 23:50

I myself have not really figured it out yet, but I'm sure you can do it with a spring. Remember the dynamometer, we hang 1H, the spring sagged by 2cm, hung by 2H, sagged by 4. It seems that this should be so, do not change the position abruptly. We will work on this.

13.08.2010, 16:08

13.08.2010, 18:43

Dima's tail comes back on its own, under its own weight without springs? I understand that the wind turbine (generator) is always deflected by some degree, the stronger the wind, the greater the deflection?

13.08.2010, 23:27

I have doubts that the tail will smoothly move away from the wind. There is an equality of forces, and as they coincide, the tail will go away. I have not experienced it yet, and it is only intuitive. The spring, yes, can deflect smoothly. We must ask around those who have made 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. Closer to winter, I will probably do it.

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 TAKING) and translate the calculations? : http://www.thebackshed.com/Windmill/Docs/Furling.asp

19.01.2011, 16:03

Goga65,
http://translate.google.ru/translate?js\u003dn&prev\u003d_t&hl\u003dru&ie\u003dUTF-8&layout\u003d2&eotf\u003d1&sl\u003den&tl\u003dru&u\u003dhttp%3A%2F%2Fwww.thebackshed.com%2FWindmill%2FDoling cs% 2FWindmill%2FDoling cs% 2 .asp

19.01.2011, 16:19

Valeriy, Thank you, but not everything is clear. Have you considered your tail to your VG or from a "bully"?

19.01.2011, 16:28

I counted according to Vladimir's formula.
.php? t \u003d 67

19.01.2011, 17:31

Guys, who can help me calculate the tail: d \u003d 1.5m, 20m.s. P \u003d 300W (if needed)?

19.01.2011, 20:49

For one and a half meter, 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 the shock absorber.

19.01.2011, 22:38

Goga65, read it carefully. Everything is clear there. Once again, I bring Vladimir.
Normal 0 false false false MicrosoftInternetExplorer4 Consider the mechanism of the oblique kingpin. the operation of the entire circuit is similar to the operation of a screw thread. When the screw pair is working, the equality of the work performed by the torque of the rotating screw and the screw working on the counter force is observed. Thus, the moment applied to the screw axis in our case depends on the wind and is well reflected in the table I gave, the table, essna, it is necessary to correct it by an order of magnitude, as Viktor Afanasyevich just noted, God bless him. Because the movement of the screw linearly depends on the angle, it does not matter what angle is considered for comparison of works, 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 2 meters away 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 tilt of the kingpin is as follows:
M * P / 2 \u003d 500 * 2sin a
solving the equation for any moment from the table with respect to the angle a, we obtain the angle of inclination of the king pin for the protection to operate in the wind corresponding to this moment.

31.01.2011, 20:32

I constructed a VG from a Bulgarian motor, but did not bring it to completion, since it turned out to be very heavy, for a thin mast, now I am trying to finish the design. I am trying to make a multiplier (1: 3.5) from a pulley (in my opinion from a washing machine) and a roller ( carved from the salinblock VAZ 2108), the screw diameter is 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 tail 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, The pictures show that you have the ability to move the king pin to the left. That is, increase the distance 9cm. It's good. If your tail is ready, you need to weigh it. At the point of attachment of the tail, take 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, the kingpin is unlikely to be displaced, unless cut off and digested, and tomorrow I'll weigh the tail

01.02.2011, 22:27

And I tried to find my Bulgarian one of these days, it was not 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 hand support, the weight changes)

02.02.2011, 23:13

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

03.02.2011, 11:52

Sergey, While I will not cut off (on the Czech, this angle is somewhere 5-7 degrees), do you calculate at what wind the trigger will be? -Check, and then if we redo it, there will be both theory and practice (if it were not for the snow on the roof, it already spinning in the wind)

03.02.2011, 17:05

03.02.2011, 17:54

Yes, I saw a video on YUTB, then there the propeller was turning clockwise, and the tail was on the right (looking at the propeller), I read on the forum that for such an arrangement of the tail, the propeller must turn counterclockwise ?! How is it correct, who will tell you?

This is nonsense.

03.02.2011, 19:01

baysun, Nonsense in what?

Alexander

03.02.2011, 20:47

Goga65, if the screw rotates clockwise (when looking at it from the front), then the withdrawal should be made 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 propeller blade or hub is not rigid enough) ... With the correct direction of the windmill's turn when folding the tail, 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 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.
Alexander, And it is possible a little more in detail. Let's leave the gyroscope for now, here it is more understandable. 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 load on the blades to the right of the mast should decrease, and those on the left should increase. That is, to experience an additional load from the reversal due to these precessional forces. But where does up and down? Please explain?

Alexander

03.02.2011, 22:00

Let's leave the gyroscope for now, here it is more understandable. 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 (while 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 very - that neither is - precession. Accordingly, when turning to the left - the propeller disk will want to tilt up. We are looking at the screw from the front, right? I hope we can somehow tell the difference between up and down (although it's incredibly difficult, I understand ...)?
As for 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.
It is easy to check on the simplest model: it is enough to take a thin tin disc and, setting it loosely on a knitting needle, bring it into rotation. Rotating this disk in one direction or another and trying to unfold it relative to the vertical, you can see everything with your own eyes and, accordingly, understand.

03.02.2011, 22:21

Alexander, What's in the pictures from: http://www.thebackshed.com/Windmill/Docs/Furling.asp -the screw turns counterclockwise?

Alexander

03.02.2011, 22:26

The direction of rotation is not drawn there, but should rotate counterclockwise.

03.02.2011, 22:33

Alexander, So I'm doing it wrong. I read somewhere and wrote down that everything is the other way around, and his Czech (but he works and the tail "plays"), and now the second Bulgarian, I did not weld the frame correctly - my blades were cut out to rotate for an hour. arrow, and threads for twisting.

Alexander

03.02.2011, 22:46

Goga65, Well, these are babies. They don't care. You don't need to take them away at all. But as soon as the windmill becomes big, this is where it begins ... Everyone remembers Viktor Afanasyevich's windmill? There this effect manifested itself already twice: the first time, when the burst hit the mast and was slightly damaged, and the second time, when the windmill collapsed with the blades flying off ...
I recommend doing the tin disc experiment I mentioned above. This is better than any theory.

03.02.2011, 22:58

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

Alexander

03.02.2011, 23:18

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

03.02.2011, 23:57

I have already checked it: i_am_so_happy: ... I confirm with left rotation and left turn, the disc approaches the conventional mast of photo 1. With left rotation and turn to the right, the disc moves away from the conventional mast of 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 (while 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 very - that neither is - precession.

Damn, well, my windmill is wrong. : scratch_one-s_head:
As the saying goes: do not take everything into account, mistakes cannot be avoided.
In the summer I will do it, move the tail to the other side, and move the propeller to the other - everything is mirrored horizontally.

Only I would like to clarify, turn to the right, if we look at the propeller from the front, then the left part of the propeller approaches, and the right part of the propeller is removed - right? And then the relativity of the turn can be counted from different points and the right will turn into the left :))

04.02.2011, 06:41

Only I would like to clarify, turn to the right, if we look at the propeller from the front, then the left part of the propeller approaches, and the right part of the propeller is removed - right? And then the relativity of the rotation can be calculated from different points and the right will turn into the leftAha, but the direction of rotation will also change. I will paraphrase. 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,
the bottom of the disk - to the left,

Where is the reference point taken from the disc?

04.02.2011, 06:55

do not take into account everything, 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 turn it clockwise. Is this rotation right or left?
This is a right rotation, I mean to put all the points, and there was no ambiguous interpretation and conclusions;) there must be clarity everywhere, so that there are no doubts about the correct understanding of the subject of discussion .... we live in a world where EVERYTHING is relative;)

04.02.2011, 08:17

there were no doubts about the correct understanding of the subject of discussion .... we live in a world where EVERYTHING is relative. Just tried to describe it in clever words and alas, nothing happened. Whatever left-right, and the mast can be brought from above, all the processes of movement are considered in space. Where there is a point, a line and a plane. In this case, we consider the position of the 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. The points on the disk located in the direction of the force application tend to move away from the fulcrum, and approach from the opposite side. When a point moves along the direction of application of the force, it tends to move away from the support. And the points moving towards the applied force approach the support. In heaped up. I'll check it out in the evening. Now is the time to run to work.

04.02.2011, 09:29

No guys, in my opinion this is all nonsense.
If the blades have a tendency 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 point slightly upward from 3 to 5 radices. This eliminates the possibility of grazing the mast blades.
And where it will rotate is not important. Whatever one may say, centrifugal forces will still try to keep the screw in one plane. In a strong wind, the pressure on the propeller on the left or 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 like to bend, so you need to try to take into account all the little things, no matter how small they seem.

04.02.2011, 10:49

Not a fig did not understand! In the photo, Seryoga is a Bulgarian, but she has no reverse rotation. I'm going to twist the drill myself!

04.02.2011, 11:21

I don’t know, maybe I’m wrong, only on large screws, I think, such troubles are on the drum.
These are small screws spinning madly, with large ones a little differently. There, in the wind, such things, in my opinion, are not felt.
In principle, I again didn’t get into it, I argue on the example of my wood screw.
I have never seen a screw from a pipe live. Perhaps such a thing is really relevant there.

04.02.2011, 11:52

Not a fig did not understand!
And why reverse, it is enough to turn the rotating disc to the left, then to the right.

Added after 43 seconds
using your wood screw as an example.
blades made of wood do not bend like that.

04.02.2011, 12:50

Quote: Posted by Goga65
Not a fig did not understand!
And why reverse, it is enough to turn the rotating disc to the left, then to the right. Well, it started with which direction the screw turns?
Here I cut a circle out of cardboard, inserted it into a drill through a spring and turned it, turning the drill to the left, to the right. - The actual circle tilts towards or away from the imaginary mast when cornering. As shown here: http://www.thebackshed.com/Windmill/Docs/Furling.asp and when the propeller is turned clockwise - the propeller deviates from the mast - it means that I (and you Dima too) have welded VGs 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 decision!

04.02.2011, 13:18

yes, I checked it, I did everything right :)

Added after 2 minutes
I put the CD on the axle and checked. When rotating clockwise, when folding my windmill, the blades are bent away from the mast, when the propeller returns to the wind, the blades approach the mast ... like this;)

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

Added after 1 minute
in short, then I'll test it on a drill, otherwise my experiment raises doubts about its purity ...

04.02.2011, 14:45

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

Alexander

04.02.2011, 18:58

Are you guys 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 back to the wind. When holding the drill, you are behind the windmill. Therefore, while observing clockwise rotation, one 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 are looking at the screw.
As for whether this should be taken into account or not, here is what we can say. 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 takes place in an extremely extreme mode for the propeller, and the gyroscopic forces are tens of times higher than the centrifugal ones. To make a propeller too stiff is to make it too heavy. And get even more strength. Forces breaking the swing of the blades and striving to bend the wind wheel shaft. If you make the screw elastic, then it will turn out to be lighter, but there is a danger of snagging on the mast. With all the consequences ... Therefore, all this fuss takes place 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 point slightly upwards from 3 to 5 radices. This eliminates the possibility of grazing the mast blades. And where it will rotate is not important. This excludes the blade from the force acting on the blade during braking of the air flow, and it does not matter in which direction the propeller rotates.
Whatever one may say, centrifugal forces will still try to leave the screw in one plane. Thereby reducing bending.
In a strong wind, the pressure on the propeller on the left and on the right is generally the same. We are not considering the pressure on the propeller now. We want to understand what forces (besides 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 screw rotates clockwise - the screw deviates from the mast - it means that I (and you Dima too) have VG welded correctly! If you look at photo 4, it is not clear, and you did not write in which direction the turn was made ...

Here I took a picture of my VG in a gusty wind, like the blade takes you away from the mast. At this distance from the mast, you are not threatened with grazing, rather the blade will break.

Added after 20 minutes
For the folding of the tail takes place in an extremely extreme mode for the propeller, and the gyroscopic forces are tens of times higher than the centrifugal ones. To make a propeller too stiff is to make it too heavy. And get even more strength. Forces breaking the swing of the blades and striving to bend the shaft of the wind wheel. Respect to Alexander. I once asked Dima what diameter to make the propeller shaft? He said that he read somewhere 1/80 of the diameter of the turbine. If we take 3m, then it is 37.5mm. That's when I got a lot of questions like: Based on what did this number come from? What does it 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 the six-bladed one is 2.5 times more than the two-bladed one. But hardly anyone took into account the gyroscopic forces arising at the moment the propeller was pulled out of the wind. And as Alexander noted, these forces are quite significant, and in places of stress concentration, paired with a torque, they can simply cut off the shaft.

Alexander

04.02.2011, 21:33

On what basis did this figure come from? What does it take into account?
This figure is somewhat redundant. The redundancy is taken in order not to bother calculating the strength for each specific case. If we are guided by 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 wind turbines 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 a multi-wing of 8 meters. (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 that of a high-speed three-blade. By the way, Fateev mentioned this in his book.
So what can be done on Dima's recommendation and it will be fine.

04.02.2011, 22:08

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

Alexander

04.02.2011, 22:40

It was in this way that I was taken away. When the wind speed exceeds 8 m / s. Working 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 on which side of the mast to place the propeller, but on 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 screw always rotate in the wind around its axis in one direction, no matter which one. 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 needs to be "introduced" into the wind again, and it will now turn around the mast in the opposite direction at the SAME direction of rotation of the propeller itself, and, therefore, the blades will be pressed against the mast. The described situation can be repeated exactly the opposite, the essence will not change from this.

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

Thus, if we are talking about this phenomenon, then everything ultimately (simplified) will be reduced to the calculation of the bending of a cantilever beam, which is the blade. The bending moment will depend on the magnitude of the force acting over 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 rotor. It will depend on the mass of the blade, the angular speed of rotation of the propeller, the elasticity of the material of the blade and the acceleration with which the propeller turns around the mast.

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

05.02.2011, 00:39

BUT, when the wind weakens a little, the propeller needs to be "introduced" into the wind again, and it will now turn around the mast in the opposite direction at 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 - WEAKENING, which means that when leaving the wind, the revolutions will be higher, and therefore the moment of forces is greater than when the propeller returns to the wind, which means that the propeller will bend away from the mast when leaving the wind more than when returning, tends to touch the mast ...
nevertheless, Alexander is right about the correct placement of the tail of the evacuation system.

05.02.2011, 00:44

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

All this is very arbitrary, since 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, just in my opinion, the significance of this phenomenon is somewhat exaggerated ...

05.02.2011, 00:46

The propeller ALWAYS rotates in one direction, and when it turns around the mast "back and forth" the blades will either be pressed against the mast or move away from it. But, when being pulled out of the wind, its rotational speed and turn rate are much higher than when it comes back.

05.02.2011, 00:52

But, when being pulled out of the wind, its rotational speed and rate of turn are much higher than when it comes back.

How to say, how to say ... We take it out of the wind in order to decrease the speed, and introduce it into the wind in order to increase the speed ... I do not think that they (the speed) will be so "striking" 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 ...
yes no, watch the video, how my screw turns and what speed it develops, and its diameter is 2.5 meters;)
http://www.youtube.com/watch?v\u003d3JQIf0adPDc&feature\u003dplayer_embedded

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

05.02.2011, 00:54

I was interested in another question here, namely. The wind is blowing in the forehead, and it is blowing, but the screw attachment point, when turning, begins its1 movement, at first almost perpendicular to the wind, and approaching 90 degrees, almost parallel. With all the ensuing consequences ...

06.02.2011, 23:15

Something quieted everything down.
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, do it first and then count. (Right Igor?: Scratch_one-s_head :;)).
Photo 1. Collected the necessary blanks.
Photo 2. Brewed the swivel unit.
Photo 3. I welded the generator mount, as expected, at an angle of 4 degrees.
Photo 4-5 Kingpin in two planes.
Photo 6. I strengthened it a little, the atoms turned out to be quite flimsy.
Photo 7. This is like the long-awaited TAIL started doing ...
Photo 8. Gathered everything in a heap, General view.
Photo 9. Front view.
Photo 10. Side view.
Photo 11. Top view.
Photo 12-13. As it was rightly noted, you should never forget about the limiting 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 layout or a future operating model? In photo 9, why did the tail go to the right in its original state? 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 restriction is needed at the bottom.

08.02.2011, 04:57

It seems he began 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 thirst to receive a lot of information and in a short period of time leads to superficial knowledge. Many little things 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 pin parallel to the plane of the wind wheel. It is this angle that determines the strength 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 chamfered and where the windhead is. And finally, precession. Hopefully on the animation, the spinning top rotates clockwise, that is, it has 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

Sergei, If the memory is not beaten back, Vladimir, he also said that it depends on the speed (filling).

09.02.2011, 18:32

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

Added after 6 minutes
In photo 12, the top stop is not needed, the tail restriction is needed at the bottom, just the opposite is true. Restriction is needed 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 me these formulas.

Alexander

09.02.2011, 19:06

"Blades". Page 21, message 207 ...
.php? p \u003d 2092 & postcount \u003d 207 Here everything was chewed in detail. What, how and why. It's amazing that we quickly forget everything. The formulas that Dima used to make the plate just take into account the braking coefficient 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 - this is how it will press on a flat plywood solid disc. If you divide the force in the first picture by the one in the second, you get 0.879. And the coefficient of load on the swept surface of the propeller is 0.888. Which is pretty close. Don’t you? The calculation in the second picture is suitable for a multi-wing, since it has a huge fill factor and because of this, the load on the wind wheel is close to a plywood disc of equal size. And the frontal pressure for the case of high speed, naturally, turns out to be less. Do you need to explain further, or is everything already clear? :))

16.02.2011, 09:42

I began to reread this topic first. Good topic, needed. And as before, I 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 this come from? Theoretically, we simply cannot turn more than 90 degrees. And as far as who needs it, this is the second question. That is why this formula contains FURL resistance \u003d Tail Weight * Sin (Pivot angle in degrees) * Sin 45o.
yes it returns under its own weight, but I think that it comes back late, yes it is rejected by a small degree, I have somewhere 3-5 degrees
gda98, What are these degrees? If up, then everything is clear. And if against a reversal, then this is completely different ...
Work when lifting the tail \u003d mgh m weight in kg g - 9.81 gravity h - height of the point at the center of gravity h \u003d distance in meters from the center of rotation of the tail kingpin to the center of gravity * sina (sine of the angle of inclination of the kingpin) This is the same incomprehensible place. Why center of gravity? We're not lifting it at the center of gravity, are we? Why didn’t I take a dynamometer with me? I’d already checked everything experimentally.
Sergei, While I will not cut off (on the Czech, this angle is somewhere 5-7 degrees), do you calculate at what wind the trigger will be? Tail 1.5m * 6kg * 0.342 (sin20) * 1 (sin90) \u003d 3kg. It will resist the tail with such an effort. Go ahead. With what force do we need to press down on the screw in order to overcome these 3kg on the 0.06m lever. 3 / 0.06 \u003d 50kg. We look at the table and see that on a 1.9m propeller it will be with a wind of 18m / sec. So, if I understand everything correctly, it just won't start to fold before this wind. He didn't leave the side of the house, first tore off one and then the second blade (d \u003d 1.5 m), and the floating tail did not help, my assumptions that it works as a stabilizer and not a drift from the wind, unfortunately, it was justified! It's a shame, it's 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, more powerful, more reliable ...

16.02.2011, 12:16

Quote: Posted by Goga65
CZECH did not leave aside - first tore off one and then the second blade (d \u003d 1.5m), and the floating tail did not help - my assumptions that it works as a stabilizer and not a drift from 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, more powerful, more reliable ...
In the Czech, the kingpin has an angle of inclination in my 7 degrees (I copied the tail from Valerian's autogenes)

17.02.2011, 11:53

Why 90grad? Where did this come from?
http://alter-energo.ru/viewtopic.php?p\u003d22966#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 many places that I do not understand. For example, nowhere is the distance from the screw attachment to the mast axis taken into account, and the distance of the tail position on the pivot to the same mast axis. But this is a two-armed lever. And it's good if the shoulders are the same or close to each other, you can neglect. And if they differ two times? 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 pp. 191-192 and pp. 201-212, it seems to me that Fateev considered the issues that concern you there..php? P \u003d 430 & postcount \u003d 6

Also, I drew attention to the message of Vladimir, where he says that the screws calculated according to the Zhukovsky scheme and calculated according to the Sabinin scheme give different pressures. http://alter-energo.ru/viewtopic.php?p\u003d11535#11535

19.02.2011, 12:41

serggrey, Thanks for the help. Someone on the forum said that almost everything that we have was studied and forgiven at the beginning of the 20th century. Vladimir wrote (The situation is worse if the propeller is not calculated according to any of these theories ... Then there is nowhere to go - you will have to take its sweeps and integrate.) Our calculations, even if they come down to understanding the processes that are taking place, are not bad.

10.03.2011, 18:50

I don’t know where to write a question - I decided here.
Interested in how reliable wind turbine protection from a hurricane with a folding tail system is?
Still wondering whether it reliably protects a windmill with a propeller size of 3 meters and more in high winds, for example, from 15 ms and above?
If there are owners of such wind generators, please, please respond. Write what kind of wind did your wind turbines withstand?

10.03.2011, 23:12

i want to ask a question experienced. Has anyone tried such a protection system, or can you tell us about the pros and cons?

10.03.2011, 23:58

makhno, Well, where's the catch? Like the whole tail does not fold, but the plumage?

11.03.2011, 00:07

LEX, there is no catch. Soon I will have a question about storm protection (well, I really do not want a windmill that folds in half. Not beautiful). so I'm considering options. this one seems to be nothing. that's why I want to know the pros and cons of this design from competent people.

11.03.2011, 00:17

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

11.03.2011, 00:41

So what is the scheme? unclear from the photo! You can and I join the discussion. I didn’t understand anything, even the intention of the 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 leave the wind even in weak winds or will it still "keep the nose in the wind" :) And what 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 has calculated. I do not yet understand how, even though it is her that I am trying to overcome.

11.03.2011, 01:20

makhno, after reading, I understood the mechanics, the windmill itself is displaced to the side, when the wind force the large propeller begins to bend back and the tail unit remains in the wind, and the tail turns relative to the propeller (only the plumage is correct, the tail rod itself is stationary), a brake drive is connected to this tail, such a system cannot be used on powerful windmills - the brake pads will quickly wear out and the braking will disappear, up to 300-500W is possible, but you will probably have to change the pads once a year or two.

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? It depends on which pipe and which mill ...

11.03.2011, 16:18

11.03.2011, 20:47

Bosoiy

12.03.2011, 00:11

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

It happens on my veranda that it freezes in winter. But it never burst. There, after all, the plastic is thick, due to this and durability. Yes, it will be convenient in installation. Only the plumage needs to think about what would pull it back.: Bye:

12.03.2011, 00:11

Still wondering if it reliably protects a windmill with a propeller size of 3 meters and more in high winds, for example, from 15 ms and above? Previously, different types of wind turbines were produced in Russia. At least - for one of them I was able to find data on the diameter of the main shaft bearing. It turned out to be 75 mm in diameter for a multi-wing of 8 meters. (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 out of the wind in the way in which we are trying to figure it out.
It was in this way that I was taken away. When the wind speed exceeds 8 m / s. The working speed is only 25 - 35 rpm. I hope I answered;) ...

12.03.2011, 09:05

On my veranda it happens that it gets cold in winter.: Bye:

This is no load, but how will it behave under load, and even after icing?

15.03.2011, 12:05

How without load? There are simply two types of pipe expansion. 1.-Linear. 2. Radial. In my case, the second. And how it will behave in the first is unknown.

16.03.2011, 11:16

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

16.03.2011, 12:21

do you need to make a tail to fold?
for a 500W wind turbine is already needed.

16.03.2011, 17:33

Dima thanks. So you need to do it.

22.04.2011, 06:39

I found a folding tail excel, it is not verified, who has a desire to check, check and ask to report the results, if she thinks correctly, then we will put it in the library.

22.04.2011, 10:25

I liked Evgeny Boyko's plate more

22.04.2011, 10:29

Found a folding tail
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'm going to do the blades.

22.05.2011, 15:31

I read everything from beginning to end, and so there is nothing specific. I tried to look at the plates for the calculation, I need a password. How to calculate roughly? 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 to open: You cannot use this command on a protected sheet (Unprotect a sheet (Service)). I open there a password plate comes out.

22.05.2011, 20:27

Paul, what kind of table? There are several of them.

22.05.2011, 20:30

gda98, On this page at the end, I don't know which one suits me?

22.05.2011, 20:45

Pavel, you do not need to press 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 work out anything. It's okay. I have the rotation of the blades to the left, so that the nut does not unscrew. Which way should the tail turn? And if you put it in the middle or so you can't?

24.05.2011, 21:40

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

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

Carved a sleeve for the tail on bearings. How is the tail length and size determined?

28.05.2011, 12:07

About protection by the "tail" (for Pasha): from the info, I did something like this:
tail length \u003d wind wheel diameter
tail area \u003d 10-15% of the wind wheel area
angles of inclination "copied" from Valera (http: //site/showthread.php? t \u003d 28 & page \u003d 7)
Here's some more info on the topic: http: //evgenb.mylivepage.ru/page/

28.05.2011, 14:55

Goga65, Thank you. Let's read it.

28.05.2011, 15:36

Doesn't the length of the tail lever depend on the distance between the propeller and the swivel unit?

05.06.2011, 10:28

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

05.06.2011, 11:54

noticed that some people put generators on the turntable at an angle of 4-5 degrees (vertical). What for?
so that the tips of the blades are farther from the mast and do not hit it.

05.06.2011, 12:00

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

05.06.2011, 12:14

put generators on a swivel unit at an angle of 4-5 degrees (vertically)
To prevent the blade from hitting the mast in strong winds.

From the center horizontally, you need a generator or tail. This is me about wind protection.
both.

Added after 3 minutes
but then we lose a few percent of the power ..?!
I was tilting to 15 (albeit up when I was adjusting the pull), and did not notice the 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 with the calculation of the tail, it's still not clear.
.gif A trial of calculating the tail..php? attachmentid \u003d 2742 & d \u003d 1306566465) - when both the generator and the tail are displaced in relation to the center - what value should be substituted 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 it is the sum of the displacements 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 to offset. Compensation is the second meaning.
I can give you about ten more meanings of the translation, but how does this help answer the question?

06.06.2011, 22:26

logically, this is the sum of the displacements of the tail and the propeller from the center of the mast.
No DIP, this is turbine displacement. Together with the force of pressure on the propeller, it 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 wind turbine, we spread the turbine and tail by this distance?
Sanya77, did you talk about this compensation?

07.06.2011, 03:10

DIP, I don't agree about the distance between the turbine and the tail. But this is just my personal opinion. I will try to justify it. Yes, due to the 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 pulley. The pivot, having an inclination, will put the projection of this force on the plane of the table and on the lever of applying this force from the pivot axis we get the tail moment. That is, in my understanding, 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 repeat that this is just my opinion ...

07.06.2011, 10:44

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

07.06.2011, 11:38

I, too, not how can I not deal with this tail? Need to start doing and just don’t know where to start? There are a lot of incomprehensible 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 \u003d 1.29kg / m ^ 3. Tail area \u003d X m ^ 2,
Wind speed \u003d U m / s ..
Tail arm length \u003d Z m.
How to calculate from all this the pressure on the swivel unit - for example, with one meter of lever and with two? The same question, how does the pressure on the rotary knot of the screw lever depend on the KIEV? And most importantly, I just can't understand .. Why should the generator be displaced relative to the rotary knot? And how will the length of the offset arm work to our advantage?

07.06.2011, 12:20

DIP, as for me, so the tail lever is what I marked in green. And it depends on the distance of the attachment point of the tail from the axis of rotation.
I supplement the drawing with a new point. Segment A is equal to segment B.
Those. the attachment point from the axis of rotation is at the same distance. I don't think we'll get the same effect when attaching the tail to the ends of the line segments.

07.06.2011, 14:49

And I think it's the same. If in either case the kingpin is tilted back, this table will stay in one place.

Added after 12 minutes
And most importantly, I just can't understand .. Why should the generator be displaced relative to the swivel unit? And how will the length of the offset arm work to our advantage? Well, you give a brother: scratch_one-s_head: ...
After all, you can not only direct the propeller into the wind with the tail, but you can also take it out of the wind. When it exceeds some speed of course. And earlier it is not necessary, there the propeller should look to 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 displaced, then the tail will not fold? Or if you move the generator, then do the folding tail inappropriately?

07.06.2011, 15:06

Need to start doing and just don’t know where to start? There are a lot of incomprehensible 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 \u003d 221 There is everything that I found: 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 propeller diameter. Although this must be treated differentially. For example, I piled everything in a heap, and then just started measuring it. :))

07.06.2011, 15:25

And unless the generator is displaced, then the tail will not fold? And with what business he develops ...
Or if you displace the generator, then the folding tail is inappropriate? I hope this schematic will explain how this system works.

07.06.2011, 15:29

Sergey, you are right. Spaced vectors, the dependence on the distance of the attachment point from the axis of rotation along a straight line perpendicular to the turbine is obtained.
Dealt with 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 left rotation of the propeller, the generator is located to the right of the mast. Although when I applied 20kg to the blade at a distance of 0.75R 20kg, 15 centimeters remained to the mast. Although this effect is present. A completely different matter is gyroscopic forces, 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 \u200b\u200b4 square meters, the tail area is 0.4 square meters. Length from the axis of attachment 1.6m + 0.3m to the axis of the mast. The weight of the tail is 4.2 kg and the weight at the tip is 2.6 kg. In principle, everything is fine and I grab the kingpin on the floor at an angle of 20 degrees. But how much I watched this whole thing, I never saw that the screw tried to turn away from the wind. Although, in comparison with Goga, the propeller is 2 times larger in area, it is offset from the mast 2 times further 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 coarse it, it's much easier, just hooked some piece of iron on the tail and that's it. But as you can see, it was not there. Now you have to either lighten the tail, or reduce the tilt 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,
At me (at the Czech), the tail begins to drift to the side, even with the screw off !?

11.06.2011, 00:01

11.06.2011, 02:33

I found it on my computer. Once read and preserved.
The calculation of the tail with an inclined kingpin which was done by Vladimir Kotlyar ...

I also toss my tail. I just can't figure out what speed to take for the stream flowing around the stabilizer. It turns out that 67% ??

11.06.2011, 03:57

I also toss my tail. I just can’t get it, The same I am toiled and I can’t get it. But just the speed of the flow near the tail worries me less than the moment of the turbine. Let me 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 about 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 the underloaded screw in the wind will continue to unwind and will not go into defense. And God forbid, the load will disappear, there will be no braking at all. Am I reasoning correctly?

11.06.2011, 04:42

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

Wrong. 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 to the gyroplane rotor and nothing is taken away. And at the same time, the rotor resistance is even greater than that of a disc with a swept surface diameter.

My tail is generally nonsense. It seems that the rotors of most wind turbines are in principle at an angle to the stream. 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 the underloaded propeller in the wind will continue to unwind and will not go into defense. And God forbid, the load will disappear, there will be no braking at all. Am I reasoning correctly?

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

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

11.06.2011, 12:43

So in this respect physics works for us, but at least something works for us. And then I already began to think, why didn't I do it with the side scapula? It doesn't matter if it stands or turns. And I think it's not difficult to make it ...

It looks like the rotors of most wind turbines basically stand at an angle to the stream. I mean, like in position 3?

11.06.2011, 14:32

I mean, like position 3?

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

Added after 2 minutes
Quite the opposite, if the screw is released without load and allowed to spin, then the axial force will increase in comparison with the nominal value, and it will just go into defense. and if you overload it, then it will pass more wind and the axial force will be less. So in this regard, physics works for us ..

Yes it is. Without a 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, this angle can be used to determine the rotation speed.

11.06.2011, 22:33

Without a 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 weather vane will momentarily stand along the wind only if it is welded to the mast. Why? I did it like that. Initially I gave him some angle.

11.06.2011, 23:02

How to make a tail correctly.?! I read and cannot understand. Him, what just do you need to take 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 carefully. Ilya Moscow State University is right. If a moment acts on the tail, it will never be along the wind because it will have to resist this moment. And the smaller this moment and the stronger the wind, the smaller the angle between the wind and the tail will be. But he will still be ...

Why do you need to get him out of the shadows? Everything is calculated. Simply put it this way. In the shade, you need 0.5 square meters for confident taxiing on some kind of lever, and without the shade 0.3 square meters. on the same lever.

11.06.2011, 23:43

Sergei, what moment, acting on the tail, prevents the rotor from standing perpendicular to the wind?

12.06.2011, 00:14

If we take this position as the starting position, then only there will be some pressure on the turbine, the tail will immediately go to the side trying to compensate for this moment. But the turbine will already stand at some angle to the wind, and not perpendicular. How much 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 biased.

12.06.2011, 01:20

Why then move it?

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

12.06.2011, 01:46

Have you read this article? http://translate.google.ru/translate?js\u003dn&prev\u003d_t&hl\u003dru&ie\u003dUTF-8&layout\u003d2&eotf\u003d1&sl\u003den&tl\u003dru&u\u003dhttp%3A%2F%2Fwww.thebackshed.com%2FWindmill%2FDoling cs% 2FWindmill%2FDoling cs% 2 .asp This topic actually started with her. And there are such pictures. Now think for yourself why to displace. Tomorrow on the carpet with an explanation of why you started everything like that: yes: ...

12.06.2011, 02:08

It always seemed to me that a propeller without a lever relative to the mast itself would seek the path of least resistance to the wind flow. After all, in the absence of a tail, even though 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 point, then why complicate the whole structure by adding one more lever, which is unclear how to calculate it?

12.06.2011, 02:30

That's right, it will look, and it will be exactly behind the mast, but not parallel, but perpendicular to the wind - you get a leeward version.

If the option is windward, then you need a tail.
if the windward propeller needs to be taken out of the wind, then the tail should fold.
for the tail to fold, you need an offset.

Added after 1 minute
.... adding one more lever, which is unclear how to calculate?

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

12.06.2011, 05:46

We consider the balance of forces and moments, we carefully knock everything - flies in one direction, cutlets - in the other.
The class is petruha256, and then you write to Bosom, but it is the same thing. "Why displace?" and that's it :)

12.06.2011, 09:43

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

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

12.06.2011, 12:04

This topic actually began 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 Moscow State University
Without a 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 runaway will change not due to the rotation of the blades, but due to the fact that the peripheral speed increases, i.e. in fact - speed.

12.06.2011, 14:40

petruha256, Let's say the screw is 2m. The original translation is bad and much remained incomprehensible to me. How to calculate the lever of its displacement?

Without getting into the jungle something like this.

(1) Fa * x * pi / 2 \u003d m * g * l * sin (a).

Fa is the axial force on the screw.
according to Sabinin (2) Fa \u003d 1.172 * pi * D ^ 2/4 * 1.19 / 2 * V ^ 2
according to Zhukovsky (2.1) Fa \u003d 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 - the desired offset (offset);
m is the mass of the tail;
g - acceleration of gravity;
l is the distance from the king pin to the center of gravity of the tail;
a - angle of inclination of the king pin.

Let's say - the propeller is 2 m, the wind speed at which the tail should fold \u003d 10 m / s
count according to Zhukovsky Fa \u003d 0.888 * 3.1415 * 2 ^ 2/4 * 1.19 / 2 * 10 ^ 2 \u003d 165Н

Tail weight \u003d 5 kg,
distance from the kingpin to the center of gravity of the tail \u003d 2m,
kingpin tilt angle \u003d 20 degrees

X \u003d 5 * 9.81 * 2 * sin (20) /165/3.1415*2\u003d0.129 m.

12.06.2011, 16:07

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

Added after 15 minutes
The area of \u200b\u200bthe tail wing is also not visible, but a lot should depend on its shape too.

12.06.2011, 16:10

It depends, but not much. If the screw is loaded to the maximum possible KIEV of this screw, then you can use these formulas.
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 - the formulas for the ideal screw.

Added after 1 minute
The tail wing area is from a different opera - one that should provide wind taxiing and hold the tail in the right direction, and not at all one that should fold to protect against a hurricane.

12.06.2011, 16:25

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

12.06.2011, 22:04

petruha256, Thank you too. It seems a bit clear. I have a propeller with a diameter of two meters, an offset of 0.129 m, a tail weight of 5 kg, an angle of inclination of a king pin 20 gadus. Do I understand you correctly? It is still unclear what the tail area should be? And if rotation is right 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 should make the distance from the kingpin to the center of gravity of the tail 2m? Well, this is the tail of three meters will be .. Not too much eh?

12.06.2011, 22:36

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