Do-it-yourself vertical windmill (5 kW). Ventilation deflector DIY wind fan rotary turbine

Deflectors are attached to pipe outlets natural ventilation over the roofs of small businesses, public buildings, residential buildings. Using wind pressure, deflectors stimulate draft in vertical ventilation ducts. The second important function of deflectors is to protect against rain and snow getting into the ventilation shafts. Dozens of models of ventilation deflectors have been developed, the design of some is described below. The simplest versions of deflectors can be made with your own hands.

Ventilation deflector device

Any type of ventilation deflector contains standard elements: 2 glasses, brackets for the cover and a pipe. The outer glass expands downward, and the lower one is flat. The cylinders are placed on top of each other, and a cover is attached above the top one. At the top of each cylinder there are ring-shaped bumpers that change the direction of air in a ventilation deflector of any size.

The releases are installed in such a way that the wind on the street creates suction through the spaces between the rings and accelerates the removal of gases from the ventilation.

The design of the ventilation deflector is such that when the wind is directed from below, the mechanism works worse: being reflected from the lid, it is directed towards the gases that exit into the upper hole. This disadvantage is present to a greater or lesser extent in any type of ventilation deflector. To eliminate it, the lid is made in the shape of 2 cones, fastened with bases.

When the wind is from the side, the exhaust air is removed simultaneously from both above and below. When the wind is directed from above, the outflow occurs from below.

Another device for the ventilation deflector is the same glasses, but the roof is in the shape of an umbrella. It is the roof that plays an important role here in redirecting the wind flow.

The principle of operation of the ventilation deflector

The principle of operation of the exhaust ventilation deflector is very simple: the wind hits its body, is cut by the diffuser, the pressure in the cylinder decreases, which means the draft in the air increases. exhaust pipe. The greater the air resistance created by the deflector body, the better the draft in the ventilation ducts. It is believed that deflectors on ventilation pipes installed slightly at an angle work better. The efficiency of the deflector depends on the height above the roof level, size, and shape of the housing.

Ventilation deflector in winter period There is frost on the pipes. On some models with a closed body, the frost is not visible from the outside. But when the flow area is open, ice appears from the outside of the lower glass and is immediately noticeable.

A properly selected deflector can increase ventilation efficiency by up to 20%.

Most often, deflectors are used in natural draft exhaust ventilation, but sometimes they enhance forced ventilation. If the building is located in areas with rare and weak winds, the main task of the device is to prevent a decrease or “overturning” of the draft.

Types of deflectors

When choosing a ventilation deflector, you can get confused by the variety.

The most common types of ventilation deflectors today are:

TsAGI;
Grigorovich;
star-shaped "Shenard";
ASTATO open;
spherical "Wolper";
H-shaped.

Plastic ventilation deflectors are rarely used because they are short-lived and fragile. It is allowed to install plastic deflectors for basement ventilation, ground floors. Plastic deflectors are widely used only as car accessories.

Some consumers mistakenly call distribution devices for ventilation suspended ceilings deflectors. Ventilation deflectors are installed only at the ends of exhaust ducts. Ventilation of exhaust ceilings is provided by diffusers and anemostats, through which air penetrates evenly and in the required quantities into the room.

Deflector ASTATO

A model of a rotating ventilation deflector that uses both mechanical and wind draft. When there is sufficient wind force, the engine is switched off and ASTATO operates on the principle of an exhaust ventilation deflector. When there is a calm, the electric motor is started, which does not in any way affect the aerodynamics of the ventilation system, but provides sufficient vacuum (no more than 35 Pa).

The electric motor is very economical; it is turned on by a signal from a sensor that measures the pressure at the outlet of the ventilation duct. In principle, for most of the year the ventilation deflector operates on wind draft. The ASTATO ventilation deflector device includes a pressure sensor and a time relay that automatically starts and stops the engine. If desired, this can be done manually.

Static deflector with ejection fan

The partially rotating ventilation deflector is a new product that has been working very successfully for several years. DS deflectors are installed at the outlets of the ventilation ducts; low-pressure fans with reduced noise output are located just below. The fans are started by a pressure sensor. The glass is made of galvanized steel with thermal insulation. Soundproofed air ducts and drainage are connected to it. The entire structure is covered from below with a suspended ceiling.

Deflector-vane

The device belongs to the category of active ventilation deflectors. It is rotated by the force of moving air currents. The housing and covers rotate due to the bearing module. While moving between the canopies, the wind forms a zone of low pressure. The advantage of this type of ventilation deflector is the ability to “adapt” to any wind direction and good protection of the chimney from the wind. The disadvantage of a rotating ventilation deflector is the need to lubricate the bearings and monitor their condition. IN very coldy the weather vane freezes over and does not perform its function well.

Rotary turbine

In calm weather, a turbo deflector for ventilation in the form of a turbine is completely useless. Therefore, rotary turbines are not so widespread, despite their attractive appearance. They are installed only in areas with stable wind. Another limitation is that such a turbo deflector cannot be used for chimneys of solid fuel stoves, as it can become deformed.

DIY ventilation deflector

Most often, a Grigorovich deflector is made with one’s own hands for ventilation. The device is quite simple, and the operation of this type of ventilation deflector is uninterrupted.

To make a Grigorovich ventilation deflector with your own hands you will need:

galvanized or stainless steel sheet;
rivets, nuts, bolts, clamp;
electric drill;
metal scissors;
scriber;
ruler;
pencil;
compass;
several sheets of cardboard;
paper scissors.

Step 1. Calculation of deflector parameters

At this stage, you need to calculate the dimensions of the ventilation deflector and draw a diagram. All initial calculations are based on the diameter of the ventilation duct.

H=1.7 x D,

Where N– deflector height, D– chimney diameter.

Z=1.8 x D,

Where Z– width of the cap,

d=1.3 x D,

d– diffuser width.

We create a diagram of the elements of the ventilation deflector on cardboard, do it ourselves and cut it out.

If you do not have experience making deflectors, we recommend practicing on a cardboard mockup.

Step 2. Making a deflector

We trace the patterns on a sheet of metal with a scriber and use scissors to obtain parts of the future device. We connect the parts together with small bolts, rivets or welding. To install the cap, we cut out the brackets in the shape of curved strips. We fix them on the outside of the diffuser, and attach the reverse cone to the umbrella. All components are ready, now the entire diffuser is assembled directly on the chimney.

Step 3. Installation of the deflector

We install the lower glass on the chimney pipe and fasten it with bolts. We put the diffuser (top glass) on top, clamp it with a clamp, and attach the cap to the brackets. The work on creating a ventilation deflector with your own hands ends with the installation of a reverse cone, which will help the device function even in an undesirable wind direction.

Selecting a ventilation deflector

Any owner wants to choose the most effective deflector for ventilation.

The best models of exhaust ventilation deflectors are:

disk-shaped TsAGI;
DS model;
ASTATO.

The operation of the deflector in calculations is determined by two parameters:

vacuum coefficient;
local loss coefficient.

The coefficients depend only on the model, and not on the size of the ventilation deflector.

For example, for DS the local loss coefficient is 1.4.

Russia occupies a dual position with regard to wind energy resources. On the one hand, due to the huge total area and the abundance of flat areas, there is generally a lot of wind, and it is mostly even. On the other hand, our winds are predominantly low-potential and slow, see Fig. On the third, in sparsely populated areas the winds are violent. Based on this, the task of installing a wind generator on the farm is quite relevant. But in order to decide whether to buy a fairly expensive device or make it yourself, you need to think carefully about which type (and there are a lot of them) to choose for what purpose.

Basic Concepts

KIEV – wind energy utilization coefficient. When used to calculate a mechanistic model of flat wind (see below), it is equal to the efficiency of the rotor of a wind power plant (WPU).
Efficiency – end-to-end efficiency of the APU, from the oncoming wind to the terminals of the electric generator, or to the amount of water pumped into the tank.
Minimum operating wind speed (MRS) is the speed at which the windmill begins to supply current to the load.
The maximum permissible wind speed (MAS) is the speed at which energy production stops: the automation either turns off the generator, or puts the rotor in a weather vane, or folds it and hides it, or the rotor itself stops, or the APU is simply destroyed.
Starting wind speed (SW) - at this speed, the rotor is able to turn without load, spin up and enter operating mode, after which the generator can be turned on.
Negative starting speed (OSS) - this means that the APU (or wind turbine - wind power unit, or WEA, wind power unit) to start at any wind speed requires mandatory spin-up from an external energy source.
Starting (initial) torque is the ability of a rotor, forcibly braked in the air flow, to create torque on the shaft.
Wind turbine (WM) is part of the APU from the rotor to the shaft of the generator or pump, or other energy consumer.
Rotary wind generator - an APU in which wind energy is converted into torque on the power take-off shaft by rotating the rotor in the air flow.
The range of rotor operating speeds is the difference between MMF and MRS when operating at rated load.
Low-speed windmill - in it the linear speed of the rotor parts in the flow does not significantly exceed the wind speed or is lower than it. The dynamic pressure of the flow is directly converted into blade thrust.
High-speed windmill - the linear speed of the blades is significantly (up to 20 or more times) higher than the wind speed, and the rotor forms its own air circulation. The cycle of converting flow energy into thrust is complex.

Notes:

Low-speed APUs, as a rule, have a KIEV lower than high-speed ones, but have a starting torque sufficient to spin up the generator without disconnecting the load and zero TAC, i.e. Absolutely self-starting and usable in the lightest winds.
Slowness and speed are relative concepts. A household windmill at 300 rpm can be low-speed, but powerful APUs of the EuroWind type, from which the fields of wind power plants and wind farms are assembled (see figure) and whose rotors make about 10 rpm, are high-speed, because with such a diameter, the linear speed of the blades and their aerodynamics over most of the span are quite “airplane-like”, see below.

What kind of generator do you need?

An electric generator for a domestic windmill must generate electricity in a wide range of rotation speeds and be capable of self-starting without automation and external sources nutrition. In the case of using APU with OSS (spin-up wind turbines), which, as a rule, have high KIEV and efficiency, it must also be reversible, i.e. be able to work as an engine. At powers up to 5 kW, this condition is satisfied by electric machines with permanent magnets based on niobium (supermagnets); on steel or ferrite magnets you can count on no more than 0.5-0.7 kW.

Note: asynchronous alternating current generators or collector ones with a non-magnetized stator are completely unsuitable. When the wind force decreases, they will “go out” long before its speed drops to MPC, and then they will not start themselves.

The excellent “heart” of the APU with a power from 0.3 to 1-2 kW is obtained from an alternating current self-generator with a built-in rectifier; these are the majority now. First, they maintain an output voltage of 11.6-14.7 V over a fairly wide speed range without external electronic stabilizers. Secondly, the silicon valves open when the voltage on the winding reaches approximately 1.4 V, and before that the generator “does not see” the load. To do this, the generator needs to be spun up quite decently.

In most cases, a self-generator can be directly connected, without a gear or belt drive, to the shaft of a high-speed high-pressure engine, selecting the speed by selecting the number of blades, see below. “High-speed trains” have a small or zero starting torque, but the rotor, even without disconnecting the load, will have time to spin sufficiently before the valves open and the generator produces current.

Choosing according to the wind

Before deciding what type of wind generator to make, let’s decide on the local aerology. In gray-greenish(windless) areas of the wind map, only a sailing wind engine will be of any use(We’ll talk about them later). If a constant power supply is required, you will have to add a booster (rectifier with voltage stabilizer), Charger, powerful battery, inverter 12/24/36/48 V DC to 220/380 V 50 Hz AC. Such a facility will cost no less than $20,000, and it is unlikely that it will be possible to remove long-term power of more than 3-4 kW. In general, with an unwavering desire for alternative energy, it is better to look for another source.

In yellow-green, low-wind places, if you need electricity up to 2-3 kW, you can use a low-speed vertical wind generator yourself. There are countless of them developed, and there are designs that are almost as good as industrially manufactured “blade blades” in terms of KIEV and efficiency.

If you plan to buy a wind turbine for your home, then it is better to focus on a wind turbine with a sail rotor. There are many controversies, and in theory everything is not yet clear, but they work. In the Russian Federation, “sailboats” are produced in Taganrog with a power of 1-100 kW.

In red, windy regions, the choice depends on the required power. In the range of 0.5-1.5 kW, homemade “verticals” are justified; 1.5-5 kW – purchased “sailboats”. “Vertical” can also be purchased, but will cost more than a horizontal APU. And finally, if you need a wind turbine with a power of 5 kW or more, then you need to choose between horizontal purchased “blades” or “sailboats”.

Note: Many manufacturers, especially the second tier, offer kits of parts from which you can assemble a wind generator with a power of up to 10 kW yourself. Such a kit will cost 20-50% less than a ready-made kit with installation. But before purchasing, you need to carefully study the aerology of the intended installation location, and then select the appropriate type and model according to the specifications.

About security

The parts of a wind turbine for household use in operation can have a linear speed exceeding 120 and even 150 m/s, and a piece of any solid material weighing 20 g, flying at a speed of 100 m/s, with a “successful” hit, will kill a healthy man outright. Steel, or from hard plastic, a 2 mm thick plate moving at a speed of 20 m/s cuts it in half.

In addition, most wind turbines with a power of more than 100 W are quite noisy. Many generate air pressure fluctuations of ultra-low (less than 16 Hz) frequencies - infrasounds. Infrasounds are inaudible, but are harmful to health and travel very far.

Note: in the late 80s there was a scandal in the United States - the largest wind farm in the country at that time had to be closed. Indians from a reservation 200 km from the field of its wind farm proved in court that their health disorders, which sharply increased after the wind farm was put into operation, were caused by its infrasounds.

Due to the above reasons, installation of APUs is allowed at a distance of at least 5 of their heights from the nearest residential buildings. In the courtyards of private households, it is possible to install industrially manufactured windmills that are appropriately certified. It is generally impossible to install APUs on roofs - during their operation, even low-power ones, alternating mechanical loads arise that can cause resonance of the building structure and its destruction.

Note: The height of the APU is considered to be the highest point of the swept disk (for bladed rotors) or geometric figure (for vertical APUs with a rotor on the shaft). If the APU mast or the rotor axis protrude even higher, the height is calculated by their top - the top.

Wind, aerodynamics, KIEV

A homemade wind generator obeys the same laws of nature as a factory one, calculated on a computer. And the do-it-yourselfer needs to understand the basics of his work very well - most often he does not have expensive, state-of-the-art materials and technological equipment at his disposal. The aerodynamics of the APU are oh so difficult...

Wind and KIEV

To calculate serial factory APUs, the so-called. flat mechanistic model of wind. It is based on the following assumptions:

Wind speed and direction are constant within the effective rotor surface.
Air is a continuous medium.
The effective surface of the rotor is equal to the swept area.
The energy of the air flow is purely kinetic.

Under such conditions, the maximum energy per unit volume of air is calculated using the school formula, assuming the air density at normal conditions 1.29 kg*cub. m. At a wind speed of 10 m/s, one cube of air carries 65 J, and from one square of the effective surface of the rotor, with 100% efficiency of the entire APU, 650 W can be removed. This is a very simplified approach - everyone knows that the wind is never perfectly even. But this has to be done to ensure repeatability of products - a common thing in technology.

The flat model should not be ignored, it gives a clear minimum of available wind energy. But air, firstly, is compressible, and secondly, it is very fluid (dynamic viscosity is only 17.2 μPa * s). This means that the flow can flow around the swept area, reducing the effective surface and KIEV, which is most often observed. But in principle, the opposite situation is also possible: the wind flows towards the rotor and the effective surface area will then be greater than the swept one, and the KIEV will be greater than 1 relative to it for a flat wind.

Let's give two examples. The first is a pleasure yacht, quite heavy; the yacht can sail not only against the wind, but also faster than it. Wind means external; the apparent wind must still be faster, otherwise how will it pull the ship?

The second is a classic of aviation history. During tests of the MIG-19, it turned out that the interceptor, which was a ton heavier than the front-line fighter, accelerates faster in speed. With the same engines in the same airframe.

The theorists did not know what to think, and seriously doubted the law of conservation of energy. In the end, it turned out that the problem was the cone of the radar radome protruding from the air intake. From its toe to the shell, an air compaction arose, as if raking it from the sides to the engine compressors. Since then, shock waves have become firmly established in theory as useful, and the fantastic flight performance of modern aircraft is due in no small part to their skillful use.

Aerodynamics

The development of aerodynamics is usually divided into two eras - before N. G. Zhukovsky and after. His report “On attached vortices” dated November 15, 1905 was the beginning new era in aviation.

Before Zhukovsky, they flew with flat sails: it was assumed that the particles of the oncoming flow gave all their momentum to the leading edge of the wing. This made it possible to immediately get rid of the vector quantity - angular momentum - which gave rise to tooth-breaking and most often non-analytical mathematics, move to much more convenient scalar purely energy relations, and ultimately obtain a calculated pressure field on the load-bearing plane, more or less similar to the real one.

This mechanistic approach made it possible to create devices that could, at the very least, take to the air and fly from one place to another, without necessarily crashing to the ground somewhere along the way. But the desire to increase speed, load capacity and other flight qualities increasingly revealed the imperfections of the original aerodynamic theory.

Zhukovsky's idea was this: the air travels a different path along the upper and lower surfaces of the wing. From the condition of continuity of the medium (vacuum bubbles by themselves do not form in the air) it follows that the velocities of the upper and lower flows descending from the trailing edge should be different. Due to the small but finite viscosity of the air, a vortex should form there due to the difference in speeds.

The vortex rotates, and the law of conservation of momentum, just as immutable as the law of conservation of energy, is also valid for vector quantities, i.e. must also take into account the direction of movement. Therefore, right there, on the trailing edge, a counter-rotating vortex with the same torque should form. Due to what? Due to the energy generated by the engine.

For aviation practice, this meant a revolution: by choosing the appropriate wing profile, it was possible to send an attached vortex around the wing in the form of a circulation G, increasing its lift. That is, by spending part, and for high speeds and loads on the wing – most of the motor power, you can create an air flow around the device, allowing you to achieve better flight qualities.

This made aviation aviation, and not part of aeronautics: now the aircraft could create for itself the environment necessary for flight and no longer be a toy of air currents. All you need is a more powerful engine, and more and more powerful...

KIEV again

But the windmill does not have a motor. On the contrary, it must take energy from the wind and give it to consumers. And here it turns out - his legs were pulled out, his tail got stuck. We used too little wind energy for the rotor’s own circulation - it will be weak, the thrust of the blades will be low, and the KIEV and power will be low. We give a lot to the circulation - in a weak wind, the rotor will spin like crazy at idle, but consumers again get little: they just put on a load, the rotor slowed down, the wind blew away the circulation, and the rotor stopped working.

The law of conservation of energy gives the “golden mean” right in the middle: we give 50% of the energy to the load, and for the remaining 50% we turn up the flow to the optimum. Practice confirms the assumptions: if the efficiency of a good pulling propeller is 75-80%, then the efficiency of a bladed rotor that is also carefully calculated and blown in a wind tunnel reaches 38-40%, i.e. up to half of what can be achieved with excess energy.

Modernity

Nowadays, aerodynamics, armed with modern mathematics and computers, is increasingly moving away from inevitably simplifying models towards an accurate description of behavior real body in a real stream. And here, in addition to the general line - power, power, and once again power! – side paths are discovered, but promising precisely when the amount of energy entering the system is limited.

The famous alternative aviator Paul McCready created an airplane back in the 80s with two chainsaw motors with a power of 16 hp. showing 360 km/h. Moreover, its chassis was tricycle, non-retractable, and its wheels were without fairings. None of McCready's devices went online or went on combat duty, but two - one with piston engines and propellers, and the other a jet - for the first time in history flew around the globe without landing at the same gas station.

The development of the theory also affected the sails that gave birth to the original wing quite significantly. “Live” aerodynamics allowed the yachts to operate in winds of 8 knots. stand on hydrofoils (see figure); to accelerate such a monster to the required speed with a propeller, an engine of at least 100 hp is required. Racing catamarans sail at a speed of about 30 knots in the same wind. (55 km/h).

There are also finds that are completely non-trivial. Fans of the rarest and most extreme sport - base jumping - wearing a special wing suit, wingsuit, fly without a motor, maneuvering at a speed of more than 200 km/h (picture on the right), and then smoothly land in a pre-selected place. In which fairy tale do people fly on their own?

Many mysteries of nature were also resolved; in particular, the flight of a beetle. According to classical aerodynamics, it is not capable of flying. Just like the founder of the stealth aircraft, the F-117, with its diamond-shaped wing, is also unable to take off. And the MIG-29 and Su-27, which can fly tail first for some time, do not fit into any idea at all.

And why then, when working on wind turbines, not a fun thing and not a tool for destroying their own kind, but a source of a vital resource, do you need to dance away from the theory of weak flows with its flat wind model? Is there really no way to move forward?

What to expect from the classics?

However, one should not abandon the classics under any circumstances. It provides a foundation without which one cannot rise higher without relying on it. Just as set theory does not abolish the multiplication table, and quantum chromodynamics will not make apples fly up from the trees.

So, what can you expect with the classical approach? Let's look at the picture. On the left are types of rotors; they are depicted conditionally. 1 – vertical carousel, 2 – vertical orthogonal (wind turbine); 2-5 – bladed rotors with different quantities blades with optimized profiles.

On the right along the horizontal axis is the relative speed of the rotor, i.e., the ratio of the linear speed of the blade to the wind speed. Vertical up - KIEV. And down - again, relative torque. A single (100%) torque is considered to be that which is created by a rotor forcibly braked in the flow with 100% KIEV, i.e. when all the flow energy is converted into rotating force.

This approach allows us to draw far-reaching conclusions. For example, the number of blades must be selected not only and not so much according to the desired rotation speed: 3- and 4-blades immediately lose a lot in terms of KIEV and torque compared to 2- and 6-blades that work well in approximately the same speed range. And the outwardly similar carousel and orthogonal have fundamentally different properties.

In general, preference should be given to bladed rotors, except in cases where extreme low cost, simplicity, maintenance-free self-starting without automation are required, and lifting onto a mast is impossible.

Note: Let's talk about sailing rotors in particular - they don't seem to fit into the classics.

Verticals

APU with vertical axis rotations have an undeniable advantage for everyday life: their units that require maintenance are concentrated at the bottom and there is no need to go upstairs. There remains, and even then not always, a thrust-support self-aligning bearing, but it is strong and durable. Therefore, when designing a simple wind generator, the selection of options should begin with verticals. Their main types are presented in Fig.

Sun

In the first position is the simplest one, most often called the Savonius rotor. In fact, it was invented in 1924 in the USSR by J. A. and A. A. Voronin, and the Finnish industrialist Sigurd Savonius shamelessly appropriated the invention, ignoring the Soviet copyright certificate, and began serial production. But the introduction of an invention in the future means a lot, so in order not to stir up the past and not disturb the ashes of the deceased, we will call this windmill a Voronin-Savonius rotor, or for short, VS.

The aircraft is good for the home-made man, except for the “locomotive” KIEV at 10-18%. However, in the USSR they worked a lot on it, and there are developments. Below we will look at an improved design, not much more complex, but according to KIEV, it gives bladers a head start.

Note: the two-blade aircraft does not spin, but jerks jerkily; The 4-blade is only slightly smoother, but loses a lot in KIEV. To improve, 4-trough blades are most often divided into two floors - a pair of blades below, and another pair, rotated 90 degrees horizontally, above them. KIEV is preserved, and the lateral loads on the mechanics weaken, but the bending loads increase somewhat, and with a wind of more than 25 m/s such an APU is on the shaft, i.e. without a bearing stretched by cables above the rotor, it “tears down the tower.”

Daria

Next is the Daria rotor; KIEV – up to 20%. It is even simpler: the blades are made of a simple elastic tape without any profile. The theory of the Darrieus rotor is not yet sufficiently developed. It is only clear that it begins to unwind due to the difference aerodynamic drag hump and pocket of the tape, and then becomes sort of high-speed, forming its own circulation.

The torque is small, and in the starting positions of the rotor parallel and perpendicular to the wind it is completely absent, so self-spin is possible only with an odd number of blades (wings?) In any case, the load from the generator must be disconnected during spin-up.

The Daria rotor has two more bad qualities. Firstly, when rotating, the thrust vector of the blade describes a full rotation relative to its aerodynamic focus, and not smoothly, but jerkily. Therefore, the Darrieus rotor quickly breaks down its mechanics even in a steady wind.

Secondly, Daria not only makes noise, but screams and squeals, to the point that the tape breaks. This happens due to its vibration. And the more blades, the stronger the roar. So, if they make a Daria, it is with two blades, from expensive high-strength sound-absorbing materials (carbon, mylar), and a small aircraft is used for spinning in the middle of the mast-pole.

Orthogonal

At pos. 3 – orthogonal vertical rotor with profiled blades. Orthogonal because the wings stick out vertically. The transition from BC to orthogonal is illustrated in Fig. left.

The angle of installation of the blades relative to the tangent to the circle touching the aerodynamic foci of the wings can be either positive (in the figure) or negative, depending on the wind force. Sometimes the blades are made rotating and weather vanes are placed on them, automatically holding the “alpha”, but such structures often break.

The central body (blue in the figure) allows you to increase the KIEV to almost 50%. In a three-blade orthogonal, it should have the shape of a triangle in cross-section with slightly convex sides and rounded corners, and with a larger number of blades, a simple cylinder is sufficient. But the theory for the orthogonal gives an unambiguous optimal number of blades: there should be exactly 3 of them.

Orthogonal refers to high-speed wind turbines with OSS, i.e. necessarily requires promotion during commissioning and after calm. According to the orthogonal scheme, serial maintenance-free APUs with a power of up to 20 kW are produced.

Helicoid

Helicoidal rotor, or Gorlov rotor (item 4) is a type of orthogonal that ensures uniform rotation; an orthogonal with straight wings “tears” only slightly weaker than a two-bladed aircraft. Bending the blades along a helicoid allows one to avoid losses of CIEV due to their curvature. Although the curved blade rejects part of the flow without using it, it also scoops part into the zone of highest linear speed, compensating for losses. Helicoids are used less often than other wind turbines, because Due to the complexity of manufacturing, they are more expensive than their counterparts of equal quality.

Barrel raking

For 5 pos. – BC type rotor surrounded by a guide vane; its diagram is shown in Fig. on right. IN industrial version It is rare because expensive land acquisition does not compensate for the increase in capacity, and the material consumption and complexity of production are high. But a do-it-yourselfer who is afraid of work is no longer a master, but a consumer, and if you need no more than 0.5-1.5 kW, then for him a “barrel-raking” is a tidbit:

A rotor of this type is absolutely safe, silent, does not create vibrations and can be installed anywhere, even on a playground.
Bending a galvanized “trough” and welding a frame of pipes is nonsense work.
Rotation is absolutely uniform, mechanical parts can be taken from the cheapest or from the trash.
Not afraid of hurricanes - too strong a wind cannot push into the “barrel”; a streamlined vortex cocoon appears around it (we will encounter this effect later).
And the most important thing is that since the surface of the “barrel” is several times larger than that of the rotor inside, the KIEV can be over-unit, and the rotational moment already at 3 m/s for a “barrel” of three-meter diameter is such that a 1 kW generator with a maximum load of They say it’s better not to twitch.

Video: Lenz wind generator

In the 60s in the USSR, E. S. Biryukov patented a carousel APU with a KIEV of 46%. A little later, V. Blinov achieved 58% KIEV from a design based on the same principle, but there is no data on its testing. And full-scale tests of Biryukov’s APU were carried out by employees of the magazine “Inventor and Innovator”. A two-story rotor with a diameter of 0.75 m and a height of 2 m spun at full power in a fresh wind asynchronous generator 1.2 kW and withstood 30 m/s without breakdown. Drawings of Biryukov's APU are shown in Fig.

rotor made of galvanized roofing;
self-aligning double row ball bearing;
shrouds – 5 mm steel cable;
axis-shaft – steel pipe with a wall thickness of 1.5-2.5 mm;
aerodynamic speed control levers;
speed control blades – 3-4 mm plywood or sheet plastic;
speed control rods;
speed controller load, its weight determines the rotation speed;
drive pulley - a bicycle wheel without a tire with a tube;
thrust bearing - thrust bearing;
driven pulley – standard generator pulley;
generator.

Biryukov received several copyright certificates for his APU. First, pay attention to the cut of the rotor. When accelerating, it works like an aircraft, creating a large starting torque. As it spins, a vortex cushion is created in the outer pockets of the blades. From the wind's point of view, the blades become profiled and the rotor becomes a high-speed orthogonal, with the virtual profile changing according to the wind strength.

Secondly, the profiled channel between the blades acts as a central body in the operating speed range. If the wind intensifies, then a vortex cushion is also created in it, extending beyond the rotor. The same vortex cocoon appears as around the APU with a guide vane. The energy for its creation is taken from the wind, and it is no longer enough to break the windmill.

Thirdly, the speed controller is intended primarily for the turbine. It keeps its speed optimal from the KIEV point of view. And the optimum generator rotation speed is ensured by the choice of mechanical transmission ratio.

Note: after publications in the IR for 1965, the Armed Forces of Ukraine Biryukova sank into oblivion. The author never received a response from the authorities. The fate of many Soviet inventions. They say that some Japanese became a billionaire by regularly reading Soviet popular-technical magazines and patenting everything worthy of attention.

Lopastniki

As stated, according to the classics, a horizontal wind generator with a bladed rotor is the best. But, firstly, it needs a stable wind of at least medium strength. Secondly, the design for a do-it-yourselfer is fraught with many pitfalls, which is why often the fruit of long hard work, at best, illuminates a toilet, hallway or porch, or even turns out to only be able to unwind itself.

According to the diagrams in Fig. Let's take a closer look; positions:

Fig. A:

rotor blades;
generator;
generator frame;
protective weather vane (hurricane shovel);
current collector;
chassis;
swivel unit;
working weather vane;
mast;
clamp for the shrouds.

Fig. B, top view:

protective weather vane;
working weather vane;
protective weather vane spring tension regulator.

Fig. G, current collector:

collector with copper continuous ring busbars;
spring-loaded copper-graphite brushes.

Note: Hurricane protection for a horizontal blade with a diameter of more than 1 m is absolutely necessary, because he is not capable of creating a vortex cocoon around himself. With smaller sizes, it is possible to achieve a rotor endurance of up to 30 m/s with propylene blades.

So, where do we stumble?

Blades

Expect to achieve power on the generator shaft of more than 150-200 W on blades of any size cut from thick-walled plastic pipe, as is often advised, are the hopes of a hopeless amateur. A pipe blade (unless it is so thick that it is simply used as a blank) will have a segmented profile, i.e. its top or both surfaces will be arcs of a circle.

Segmented profiles are suitable for incompressible media, say hydrofoils or blades propeller. For gases, a blade of variable profile and pitch is needed, for an example, see Fig.; span - 2 m. This will be a complex and labor-intensive product, requiring painstaking calculations in full theory, blowing in a pipe and full-scale testing.

Generator

If the rotor is mounted directly on its shaft, the standard bearing will soon break - there is no equal load on all the blades in windmills. An intermediate shaft with a special support bearing and mechanical transmission from it to the generator. For large windmills, the support bearing is a self-aligning double-row one; V best models– three-tiered, Fig. D in Fig. higher. This allows the rotor shaft not only to bend slightly, but also to move slightly from side to side or up and down.

Note: It took about 30 years to develop a support bearing for the EuroWind type APU.

Emergency weather vane

The principle of its operation is shown in Fig. B. The wind, intensifying, puts pressure on the shovel, the spring stretches, the rotor warps, its speed drops and eventually it becomes parallel to the flow. Everything seems to be fine, but it was smooth on paper...

On a windy day, try holding a boiler lid or a large saucepan by the handle parallel to the wind. Just be careful - the fidgety piece of iron can hit you in the face so hard that it breaks your nose, cuts your lip, or even knocks out your eye.

Flat wind occurs only in theoretical calculations and, with sufficient accuracy for practice, in wind tunnels. In reality, a hurricane damages windmills with a hurricane shovel more than completely defenseless ones. It’s better to change damaged blades than to do everything again. In industrial installations it is a different matter. There, the pitch of the blades, each individually, is monitored and adjusted by automation under the control of the on-board computer. And they are made from heavy-duty composites, not water pipes.

Current collector

This is a regularly serviced unit. Any power engineer knows that the commutator with brushes needs to be cleaned, lubricated, and adjusted. And the mast is made from a water pipe. If you can’t climb, once every month or two you’ll have to throw the entire windmill down to the ground and then pick it up again. How long will he last from such “prevention”?

Video: bladed wind generator + solar panel for power supply to a dacha

Mini and micro

But as the size of the paddle decreases, the difficulties fall according to the square of the wheel diameter. It is already possible to manufacture a horizontal bladed APU on your own with a power of up to 100 W. A 6-bladed one would be optimal. With more blades, the diameter of the rotor designed for the same power will be smaller, but they will be difficult to firmly attach to the hub. Rotors with less than 6 blades need not be taken into account: a 2-blade 100 W rotor needs a rotor with a diameter of 6.34 m, and a 4-blade of the same power needs 4.5 m. For a 6-blade, the power-diameter relationship is expressed as follows :

10 W – 1.16 m.
20 W – 1.64 m.
30 W – 2 m.
40 W – 2.32 m.
50 W – 2.6 m.
60 W – 2.84 m.
70 W – 3.08 m.
80 W – 3.28 m.
90 W – 3.48 m.
100 W – 3.68 m.
300 W – 6.34 m.

It would be optimal to count on a power of 10-20 W. Firstly, a plastic blade with a span of more than 0.8 m will not withstand winds of more than 20 m/s without additional protection measures. Secondly, with a blade span of up to the same 0.8 m, the linear speed of its ends will not exceed the wind speed by more than three times, and the requirements for profiling with twist are reduced by orders of magnitude; here a “trough” with a segmented pipe profile, pos. B in Fig. And 10-20 W will provide power to a tablet, recharge a smartphone, or illuminate a house-saving light bulb.

Next, select a generator. A Chinese motor is perfect - wheel hub for electric bicycles, pos. 1 in Fig. Its power as a motor is 200-300 W, but in generator mode it will give up to about 100 W. But will it suit us in terms of speed?

The speed index z for 6 blades is 3. The formula for calculating the rotation speed under load is N = v/l*z*60, where N is the rotation speed, 1/min, v is the wind speed, and l is the rotor circumference. With a blade span of 0.8 m and a wind of 5 m/s, we get 72 rpm; at 20 m/s – 288 rpm. A bicycle wheel also rotates at approximately the same speed, so we will take off our 10-20 W from a generator capable of producing 100. You can place the rotor directly on its shaft.

But here the following problem arises: after spending a lot of work and money, at least on a motor, we got... a toy! What is 10-20, well, 50 W? But you can’t make a bladed windmill capable of powering even a TV at home. Is it possible to buy a ready-made mini-wind generator, and wouldn’t it be cheaper? As much as possible, and as cheaply as possible, see pos. 4 and 5. In addition, it will also be mobile. Place it on a stump and use it.

The second option is if a stepper motor from an old 5- or 8-inch floppy drive is lying around somewhere, or from a paper drive or carriage of an unusable inkjet or dot matrix printer. It can work as a generator, and attaching a carousel rotor from cans to it (pos. 6) is easier than assembling a structure like the one shown in pos. 3.

In general, the conclusion regarding “blade blades” is clear: homemade ones are more likely for tinkering to your heart’s content, but not for real long-term energy output.

Video: the simplest wind generator for lighting a dacha

Sailboats

The sailing wind generator has been known for a long time, but soft panels on its blades (see figure) began to be made with the advent of high-strength, wear-resistant synthetic fabrics and films. Multi-bladed windmills with rigid sails have spread widely around the world as a drive for low-power automatic water pumps, but their technical specifications are lower even than those of carousels.

However, a soft sail like a windmill wing, it seems, turned out to be not so simple. The point is not about wind resistance (manufacturers do not limit the maximum permissible wind speed): sailboat sailors already know that it is almost impossible for the wind to tear the panel of a Bermuda sail. Most likely, the sheet will be torn out, or the mast will be broken, or the whole vessel will make an “overkill turn.” It's about energy.

Unfortunately, exact test data cannot be found. Based on user reviews, it was possible to create “synthetic” dependencies for the installation of a Taganrog-made wind turbine-4.380/220.50 with a wind wheel diameter of 5 m, a wind head weight of 160 kg and a rotation speed of up to 40 1/min; they are presented in Fig.

Of course, there can be no guarantees for 100% reliability, but it is clear that there is no smell of a flat-mechanistic model here. There is no way a 5-meter wheel in a flat wind of 3 m/s can produce about 1 kW, at 7 m/s reach a plateau in power and then maintain it until a severe storm. Manufacturers, by the way, state that the nominal 4 kW can be obtained at 3 m/s, but when installed by forces based on the results of studies of local aerology.

There is also no quantitative theory to be found; The developers' explanations are unclear. However, since people buy Taganrog wind turbines and they work, we can only assume that the declared conical circulation and propulsive effect are not a fiction. In any case, they are possible.

Then, it turns out, IN FRONT of the rotor, according to the law of conservation of momentum, a conical vortex should also arise, but expanding and slow. And such a funnel will drive the wind towards the rotor, its effective surface will be more swept, and the KIEV will be more than unity.

Field measurements of the pressure field in front of the rotor, even with a household aneroid, could shed light on this issue. If it turns out to be higher than on the sides, then, indeed, the sailing APUs work like a beetle flies.

Homemade generator

From what has been said above, it is clear that it is better for homemade craftsmen to take on either verticals or sailboats. But both are very slow, and transmission to a high-speed generator is extra work, extra costs and losses. Is it possible to make an efficient low-speed electric generator yourself?

Yes, you can, on magnets made of niobium alloy, so-called. supermagnets. The manufacturing process of the main parts is shown in Fig. Coils - each of 55 turns of 1 mm copper wire in heat-resistant high-strength enamel insulation, PEMM, PETV, etc. The height of the windings is 9 mm.

Pay attention to the grooves for the keys in the rotor halves. They must be positioned so that the magnets (they are glued to the magnetic core with epoxy or acrylic) converge with opposite poles after assembly. “Pancakes” (magnetic cores) must be made of a soft magnetic ferromagnet; Regular structural steel will do. The thickness of the “pancakes” is at least 6 mm.

In general, it is better to buy magnets with an axial hole and tighten them with screws; supermagnets attract with terrible force. For the same reason, a cylindrical spacer 12 mm high is placed on the shaft between the “pancakes”.

The windings that make up the stator sections are connected according to the diagrams also shown in Fig. Soldered ends should not be stretched, but should form loops, otherwise the epoxy with which the stator will be filled may harden and break the wires.

The stator is poured into the mold to a thickness of 10 mm. There is no need to center or balance, the stator does not rotate. The gap between the rotor and stator is 1 mm on each side. The stator in the generator housing must be securely secured not only from displacement along the axis, but also from rotation; a strong magnetic field with current in the load will pull it along with it.

Video: DIY windmill generator

Conclusion

And what do we have in the end? The interest in “blade blades” is explained more by their spectacular appearance than by their actual appearance. performance qualities in a homemade version and at low power. A homemade carousel APU will provide “standby” power for charging a car battery or powering a small house.

But with sailing APUs it is worth experimenting with craftsmen with a creative streak, especially in the mini version, with a wheel 1-2 m in diameter. If the developers’ assumptions are correct, then it will be possible to remove all 200-300 W from this one, using the Chinese engine-generator described above.

Andrey said:

Thank you for your free consultation... And the prices “from companies” are not really expensive, and I think that craftsmen from the outback will be able to make generators similar to yours. And Li-po batteries can be ordered from China, inverters in Chelyabinsk make very good ones (with smooth sine). And sails, blades or rotors are another reason for the flight of thought of our handy Russian men.

Ivan said:

question:
For windmills with a vertical axis (position 1) and the “Lenz” option, it is possible to add an additional part - an impeller that points in the direction of the wind, and covers the useless side from it (going towards the wind). That is, the wind will not slow down the blade, but this “screen”. Positioning downwind with the “tail” located behind the windmill itself below and above the blades (ridges). I read the article and an idea was born.

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Excessive humidity and odors create an unhealthy atmosphere and even cause diseases. The quality of ventilation in a home, office or workplace directly affects the level of comfort, do you agree with this?

That is why properly arranged ventilation is the most important condition when putting construction projects into operation. A turbo deflector for ventilation helps to establish high-quality air exchange. But which one to choose and install correctly so as not to call specialists?

We will try to answer all questions in detail - this material discusses the operating principle, existing types of turbo deflectors, and installation features. Attention is also paid to maintenance and repair issues.

For a better understanding of the information presented, visual photographs and diagrams of the design of rotary deflectors have been selected, and video recommendations for troubleshooting breakdowns have been provided. The information is structured and even an inexperienced home craftsman will find it easy to understand the intricacies of choosing, installing and repairing a rotary deflector.

The operation of the turbo deflector is based on the following principles: using wind energy, the device creates a vacuum of air in the ventilation shaft, increases draft and draws polluted air from the room, ventilation duct, and under-roof space.

No matter how the direction and strength of the wind changes, the rotating head (impeller) always rotates in one direction and creates a partial vacuum in the ventilation shaft.

Image gallery

Turbine installation rules

Ventilation turbines can be installed directly on a pitched or straight roof, at the outlet of a chimney or ventilation shaft. The placement location depends on the application of the turbine.

Incredible! But it will happen soon. Third generation alternative energy sources will revolutionize the world as a whole. The beginning has already been made. Wind turbines are the electric power future of humanity.

Introduction

Although alternative types Energy technologies such as wind turbines, for example, still receive undeservedly little attention; they continue to be developed intensively. Perhaps soon the mighty of the world this will be understood that reckless mining does more harm than good, and natural views energy workers will firmly enter our daily life. This hope is closely related to the fact that some time ago the appearance of a third generation wind generator was announced.

What is a third generation wind generator

It is traditionally believed that the first generation devices that converted wind energy were ordinary ship sails and mill wings. A little over a century ago, with the development of aviation, a second-generation wind generator appeared - a mechanism whose operation was based on the principles of wing aerodynamics.

It was a breakthrough at that time! Although, if we take it as a whole, the second generation windmills are low-power, since due to their design features they cannot operate in strong winds. Therefore, in order to receive more electricity, it was necessary to increase in size, which entailed additional financial costs for development, production, installation and its operation. Naturally, it couldn’t stay like this for long.

In the early 2000s, development specialists announced the appearance of a third generation wind generator - a wind turbine. The design, operating principle, installation, and most importantly, the power of the new device is fundamentally different from its predecessors.

Device

Simplicity. This is exactly the word that can be used to describe the design of a wind turbine generator. Compared to bladed wind generators, a wind turbine has a much smaller number of working units and many more fixed elements, making it more resistant to various static and dynamic loads.

Wind turbine design:

fairing, there is internal and external;
fairing of the turbogenerator assembly;
gondola;
turbine;
generator;
dynamic fastening unit.

Among the additional systems, the wind generator is equipped with inversion, accumulation and control units. There are no systems for adjusting the blades and orientation to the wind, traditional for a bladed wind generator. The latter is replaced by a fairing, which also acts as a nozzle, catches the wind and increases its power. If we take into account that the energy of the wind flow is equal to its speed in the cube V3, then due to the presence of the nozzle this formula looks like this: V3x4 = Ex64. At the same time, thanks to its cylindrical design the fairing has the ability to self-adjust to the direction of the wind.

Advantages

Any new product or invention must always stand out in a significant way from its predecessors, and always in better side. All this can be said about the new wind generator with a turbo design. One of the main advantages of a wind turbine is its resistance to strong winds. Its design is designed in such a way that it will operate efficiently and safely beyond the critical limits for conventional bladed wind turbines: from 25 m/sec to 60 m/sec. But this is not the only advantage that a wind turbine has, there are several of them:

Lack of infrasonic waves. Scientists have finally managed to solve one of the important problems that wind turbines have. It is precisely because of the existence of such side effect The APU (wind power plant) has been criticized by opponents of alternative energy; infrasound has a negative impact on the living environment. But now, thanks to the absence of infrasonic waves, turbine-type wind generators can be installed even within city limits.

The absence of blades eliminates several tasks that faced the designers and manufacturers of the wind generator. First, significant costs of effort and money for operational control of bladed wind turbines are eliminated. Second, the wind wheel blade is the most difficult element of a wind generator to manufacture. The lion's share of the cost of a conventional wind turbine is the cost of manufacturing the blades. In addition, there are known cases when, during strong gusts of wind, the blade broke, scattering fragments over hundreds of meters.
Easy to assemble and install. All complex designs or the units are manufactured and assembled by the manufacturing plant; only the last stage of assembly and installation on the mast takes place on site. Plus, the lightness of the structural elements allows you to use the most common lifting equipment when installing the wind generator.
Connection diagram. Unlike a bladed APU, the turbine is connected via standard scheme. This fact is not affected in any way by those technical specifications, which is put forward by the future owner of the wind turbine.
The long service life is due to the materials from which the wind generator and its individual parts are made. Taking into account the preventive maintenance that is required when operating a wind turbine, the service life of the device can be up to 50 years.

Geography of turbine APU operation

The most real and optimal place installations turbine wind generator there will be a lake or sea shore. Near bodies of water, such a wind generator will work almost all year round, because thanks to its nozzle device, it is very sensitive to light breezes and other slightest manifestations of wind with a speed of 2 m/sec.

With the same success, VST will work within the city, where a conventional wind generator is unable to work for a number of well-known reasons:

Unsafety of bladed wind turbines.
The infrasound they emit.
The minimum wind speed for operation of a bladed wind generator is 4 m/sec.

An interesting fact that proves the advantage of VTU

One of the cornerstones on which the position of opponents of alternative energy is based is that wind power plants interfere with the operation of location equipment. During operation, the wind generator interferes with the passage of radio waves. Considering the size of individual wind power plants, which can range from several tens to hundreds of square kilometers, it is clear why the governments of many countries have begun to block alternative energy projects at the state level - this is a direct threat to national security.

For this reason, a French company that produces components for wind generators took on not an easy task from the point of view of execution - to make the wind power plants themselves invisible to radars, and not the space around the wind generator. For this purpose, the experience gained in the manufacture of Stealth aircraft will be used. New components are planned to be released onto the market in 2015.

But where is the fact that proves the advantage of VST over bladed wind turbines? But the fact is that wind turbines do not interfere with the operation of location equipment even without expensive Stealth technology.

Prospects for the development of alternative wind energy

The first attempts to start using a wind generator in industrial scale were undertaken back in the middle of the last century, but were unsuccessful. This was due to the fact that oil resources were relatively cheap, and the construction of wind power stations was unprofitably expensive. But literally 25 years later the situation has changed radically.

Alternative energy sources began to develop intensively in the 70s of the last century, after the pace of mechanical engineering in the world increased sharply and countries faced an oil shortage, which led to the oil crisis of 1973. Then, for the first time, the non-traditional energy sector in some countries received state support and the wind generator began to be used on an industrial scale. In the 80s, the global wind energy industry began to reach self-sufficiency, and today countries such as Denmark, Germany and Australia are almost 30% self-sufficient from alternative energy sources, including wind power plants.

Unfortunately, and perhaps fortunately, last year's trend in the oil market with unstable oil prices makes us seriously think that the times when cheap oil was good are in the past. Today, for many countries, the cheaper the oil, the more profitable it is to develop non-traditional energy; this primarily applies to the CIS countries. Therefore, there are prerequisites for wind energy to develop. Let's see how it will be.

Issues of energy independence worry the minds of not only leaders of states and enterprises, but also individual citizens and owners of private houses. With the increase in monopoly and tariffs by electricity producers, people are looking for efficient alternative power sources. One such source is a wind generator.

Main elements in a wind generator system

There are many models, options from different manufacturers, but as it shows practical experience, they are not always affordable in price and quality for a wide range of consumers. If you have information, certain knowledge of electrical engineering and practical skills, you can make a wind generator yourself.

Operating principle and main elements

The operation of a homemade wind generator is no different from industrial models; the operating principles are the same. Wind energy is converted into mechanical energy by rotating a generator rotor, which produces electricity.

Main design elements (Fig. above):

propeller with blades;
a rotation shaft through which torque is transmitted to the generator rotor;
generator;
design for mounting the generator at the installation site;
if necessary, to increase the rotor speed, a gearbox or belt drive can be installed between the shaft with the propeller and the generator shaft;
to convert the alternating current of the generator into direct current, a converter is used, a rectifying diode bridge, the current from which is supplied to recharge the battery;
a battery from which electricity is supplied through the inverter to the load;
inverter converts D.C. batteries with a voltage of 12 V or 24 V AC with a voltage of 220 V.

The designs of propellers, generators, gearboxes and other elements may differ, have different characteristics, and additional devices, but the system is always based on the listed components.

Do-it-yourself selection and production

According to the design, there are two types of axis that rotate the generator rotor:

generators with a horizontal axis of rotation;

Generator with horizontal axis of rotation

generators with a vertical axis of rotation.

Rotary wind generator with vertical axis of rotation

Horizontal axes of rotation

Each design has its own advantages and disadvantages. The most common option is with a horizontal axis. These models have a high efficiency of converting wind energy into rotational movements of the axis, but there are certain difficulties in calculating and making the blades yourself. The usual flat blade shape, which was used on ancient windmills, is ineffective.

To use maximum wind energy when rotating the axis, the blades must have a wing-shaped shape. On airplanes, the shape of the wing, due to the force of the headwind, provides lifting flows. In the case under consideration, the forces of these flows will be directed to rotate the generator shaft. Propellers can have two, three, or more blades; designs with three blades are most common. This is quite enough to provide the required rotation speed.

Wind generators with a horizontal axis of rotation must be constantly turned by the plane of the propeller towards the front of the oncoming wind flow. To do this, it is necessary to use a weathervane-type tail unit, which, under the influence of the wind, like a sail, turns the entire structure with a propeller towards the headwind.

Vertical axes of rotation

The main disadvantage of this option is low efficiency, but this is compensated by a simpler design that does not require manufacturing additional elements to turn the blades towards the wind. The vertical arrangement of the axis and blades allows you to use wind energy for rotation from any direction; this design is easier to make with your own hands. The shaft rotates more stably, without sudden jumps in speed.

The average annual wind speeds on the territory of Russia are not the same. The most favorable conditions for the operation of wind generators are 6-10 m/s. There are few such areas; winds of 4-6 m/s generally prevail. To increase the rotation speed, it is necessary to use gearboxes and take into account the height and wind rose in the area where the generator is installed.

An example of wind generator manufacturing

A variant with a vertical axis of rotation is being considered.

DIY wind turbine

The easiest option for producing blades is to use a 50-200 liter metal barrel. Depending on the number of blades required, the barrel is sawn with a grinder from top to bottom into 4 or 3 equal parts.

Vertical blades from a metal barrel

You can simply use sheets of galvanized roofing iron, which can be easily cut into the desired shape with your own hands using metal scissors.

Vertical blades made of sheet iron

Subsequently, the blades are attached to the top of the rotation axis. The basis for their fastening can be wooden disks made of six-layer plywood.

It is safer to use a metal frame made of rectangular profile, to which the blades are bolted.

Example of placement of vertical blades

An example of attaching blades to a platform

The frame or disks are rigidly attached to the rotation axis; the axis itself is inserted into couplings with bearings, which are securely installed in the frame of the tower or roof of the building on which the generator is located.

Installing an axle with blades on a tower

A visual representation of the installation of a vertical axis of rotation on the roof of a building

Turbine with vertical blades.
Axle stabilization platform with double-row ball bearing.
Steel cable braces Ø 5mm.
Vertical axis, steel pipe Ø 40-50mm, wall thickness not less than 2 mm.
Rotation speed control lever.
The blades of the aerodynamic regulator are made of plywood or plastic 3-4 mm thick.
Rods that regulate the speed of rotation and the number of revolutions.
A load whose weight sets the speed of rotation.
Vertical axis pulley for belt drive, widely used bicycle wheel rim, without tube and tire.

Support bearing.
Pulley on the generator rotor axis.

A pulley for a belt drive or gears for a gearbox is attached to the lower end of the axle; this is necessary to increase the rotation speed of the rotor. Practice shows that at a wind speed of 5 m/s, the rotation of the shaft with horizontal blades from the barrel will be no more than 100 rpm. At a wind speed of 8-10 m/s, rotation reaches up to 200 m/s. This is very little for the generator to produce the necessary power to charge the battery.

A 1:10 ratio gearbox allows you to achieve the required rotation speed.

Installing Belt Pulleys

Low speed generator

The easiest way to convert mechanical rotational energy into electricity is to use car generators. But ordinary generators from passenger cars They are not recommended for windmills due to the presence of brushes in their design. Graphite brushes remove the current induced on the rotor; during operation, they wear out and require replacement. In addition, such generators are high-speed; to generate a voltage of 14 V with a current of up to 50A, 2000 or more revolutions are required.

More efficient generators for wind turbines from tractors and buses G.964.3701 with magnetic excitation of windings. They do not have brushes and operate at lower speeds. Generator G288A.3701 has three phases and is used for power supply Vehicle together with the battery. Has good characteristics for use in wind turbine systems:

produces a voltage of 28 V;
built-in rectifier produces direct current up to 47 A;
output power up to 1.3 kW;
at idle speed 1200 rpm;
with a current load of 30A, 2100 rpm is required.

The generator has suitable dimensions and weight:

total weight 10 kg;
diameter 174 mm;
length 230 mm.

Generator from MAZ - 24V

Generators of this type are used in KAMAZ, Ural, KRAZ, MAZ vehicles with engines from the Yaroslavl plant YaMZ 236, 238, 841, 842 and ZMZ 73. In order to save money, you can buy a used generator at dismantling points. To generate more electrical power at low speeds, you can make a generator with your own hands using neodymium magnets, but this is a separate topic and requires a more detailed description.

Assembly sequence

First of all, a tower or generator mounting structure is installed on the roof of the building. The vertical axis is attached to bushings with bearings, and the blades are installed.

After installing the axis with the blades, a pulley for the belt drive is fixed on the lower part.
At the level of the axle pulley, a generator with a pulley for the belt on the rotor shaft is attached to a specially prepared platform. The generator pulleys and axles with blades must be installed at the same level.

The diameter of the pulley on the axle should be approximately 10 times larger diameter pulley on the generator shaft. Based on the conditions that the estimated wind speed is approximately 10 m/s, the axis rotation speed will be up to 200 rpm.

The formula used is:

Wr = Wos x Dosd, where

Wr – generator pulley rotation speed;
Dos – pulley diameter on the vertical axis;
d – diameter of the pulley on the generator rotor shaft;
Wos is the rotation speed of the vertical axis pulley.

Wr = 200 rpm x 500mm/50 mm = 2000 rpm - sufficient rotation speed for the generator of the selected type to produce the required power.

The belt is tensioned; to do this, there must be slots in the generator mounting platform, like on a car mounting.
The output wires of the generator are connected to the battery terminals.

These generators have built-in rectifiers, the output is direct current, so the positive red wire is attached to the “+” terminal, and the negative wire is attached to the “minus” terminal.

The 24V/220V inverter input is connected to the battery, also observing the polarities.
The inverter output is connected to the circuit with the load.

Video. DIY wind generator.

Having necessary materials, practical skills in plumbing, using ready-made automobile generators with magnetic excitation of the windings, the wind generator is easy to install with your own hands. To manufacture a higher-power generator using neodymium magnets, more in-depth knowledge in electrical engineering and skills in assembling electrical equipment will be required. This is one of the most simple ways assemble a wind generator with your own hands.