Windmill: interesting facts. Mills. windmills, history, types and designs. Water and windmills

In which country and when were windmills invented?

The history of the windmill also goes far into the depths of centuries. History has not preserved the exact news about the manufacture of the first windmill. But it is known that windmills have been used in China for several millennia.. The vane wind turbine is the oldest and at the same time the best type of engine, which includes the windmill.
In ancient times, the Israelites, like other nations, ground edible grains “in millstones” to obtain flour. Working at a hand mill was not easy. Gradually, heavier millstones, which were "turned by a donkey" or other animals, came into use. But mills powered by animals also had their drawbacks. By that time, man had already learned to use the energy of water to turn a water wheel, and the energy of the wind to sail a sailboat. Around the 7th century A.D. e. in the arid steppes of Asia or the Near and Middle East combined these two ideas by making the wind turn the millstone. The first mention of windmills used in Iran for grinding grain also refers to the 7th century BC. AD So, a vertical shaft with sails came out of the millstone, which turned when the wind blew. With the help of such simple windmills, wheat or barley was ground, and water was also pumped from underground.
The first wind turbine was probably a simple device with a vertical axis of rotation, such as the device used in Persia 200 BC to grind grain. The use of such a mill with a vertical axis of rotation subsequently became widespread in the countries of the Middle East. Later, a mill with a horizontal axis of rotation was developed, consisting of ten wooden racks equipped with transverse sails. A similar primitive type of windmill is still used in many countries of the Mediterranean basin. In the 11th century, windmills were widely used in the Middle East and came to Europe in the 10th century. upon the return of the crusaders. During the Middle Ages in Europe, many manor rights, including the right to refuse permission to build windmills, forced tenants to have land for sowing grain near the mills of feudal estates. Planting trees near windmills was prohibited to ensure "free wind". In the XIV ", the Dutch became leading in the improvement of the design of windmills and widely used them from that time to drain swamps and lakes in the Rhine delta.
Early mills with sails on a vertical shaft were not very productive. But it has greatly increased with the realization that more power is produced when the blades or sails are attached to a horizontal shaft coming out of the tower. The horizontal shaft, through gears, imparted rotational motion to the vertical shaft, which turned the millstone attached to it. Then they came up with mills on goats, or "pillars". These mills rested on a pillar supported by beams, which made it possible to rotate the entire mill barn, setting the wings against the wind. For obvious reasons, the "pillars" could not be very large, and then they came up with another design: a fixed tower with a rotating roof ("tents" or "Dutch"). In mills of this type, the main shaft comes out of the roof, so that wherever the wind blows, it, together with the wings-sails, can be turned against the wind.
It is believed that windmills first appeared in the southern part of Europe (presumably in Greece) and quickly spread everywhere. Most authors believe that windmills appeared in Russia no earlier than the 17th century, although some researchers attribute their appearance in Russia to the 15th century.
At first, they were brick structures with wings that looked like huge barrels.
In 1772, a Scottish inventor replaced the sails with blinds that open and close automatically.

O.BULANOVA

They became a symbol of Holland, Don Quixote fought with them, fairy tales and legends were composed about them ... What are we talking about? Of course, about windmills. Centuries ago, they were used to grind grain, drive a water pump, or both.

The earliest example of the use of wind energy to drive a mechanism is the windmill of the Greek engineer Heron of Alexandria, invented in the 1st century BC. There is also evidence that in the Babylonian Empire, Hammurabi planned to use wind power for his ambitious irrigation project.

In the messages of Muslim geographers of the 9th century. Persian mills are described. They differ from Western designs in having a vertical axis of rotation and perpendicular wings (sails). The Persian mill has blades on the rotor, similar to the blades of a paddle wheel on a steamboat, and must be enclosed in a shell that covers part of the blades, otherwise the wind pressure on the blades will be the same from all sides and, since. the sails are rigidly connected to the axle, the windmill will not rotate.

Another type of vertical axis mill is known as the Chinese mill or Chinese windmill, used in Tibet and China in the early 4th century BC. This design differs significantly from the Persian in the use of a free-turning, independent sail.

The first windmills put into operation had sails rotating in a horizontal plane around a vertical axis. There were from 6 to 12 sails covered with reed or cloth. These mills were used for grinding grain or extracting water and were quite different from later European vertical windmills.

A description of this type of horizontal windmill with rectangular blades used for irrigation can be found in Chinese documents from the thirteenth century. In 1219, such a mill was brought to Turkestan by the traveler Yelü Chutsai.

Horizontal windmills were present in small numbers in the 18th-19th centuries. and throughout Europe. The most famous are Hooper's mill and Fowler's mill. Most likely, the mills that existed in Europe at that time were an independent invention of European engineers during the Industrial Revolution.

The existence of the first known mill in Europe (it is assumed that it was of a vertical type) dates from 1185. It was located in the village of Weedley in Yorkshire at the mouth of the River Humber. In addition, there are a number of less reliable historical sources, according to which the first windmills in Europe appeared in the 12th century. The first purpose of windmills was to grind grain.

There is evidence that the earliest type of European windmill was called the post mill, so named because of the large vertical detail that makes up the main structure of the mill mill.

When mounting the mill body, this part was able to rotate in the direction of the wind. In northwestern Europe, where wind direction changes very quickly, this allowed for more productive work. The foundations of the first such mills were dug into the ground, which provided additional support when turning.

Later, a wooden support was developed, called a flyover (goats). It was usually closed, which gave additional space for storing crops and provided protection during bad weather. This type of mill was the most common in Europe until the 19th century, until they were replaced by powerful tower mills.

Gantry mills had a cavity inside which a drive shaft was placed. This made it possible to turn the structure in the direction of the wind, applying less effort than in traditional gantry mills. The need to lift sacks of grain to high-placed millstones also disappeared. the use of a long drive shaft made it possible to place millstones at ground level. Such mills have been used in the Netherlands since the 14th century.

Tower mills appeared by the end of the 13th century. Their main advantage was that in the tower mill, only the roof of the tower mill reacted to the presence of wind. This made it possible to make the main structure much higher and the blades to be larger, so that the rotation of the mill became possible even in light winds.

The upper part of the mill could turn in the wind due to the presence of winches. In addition, it was possible to keep the roof of the mill and the blades in the direction of the wind due to a small windmill installed at right angles to the blades. This type of construction has become widespread in the territory of the British Empire, Denmark and Germany.

In the Mediterranean countries, tower mills were built with fixed roofs, because. the change in wind direction was very slight most of the time.

An improved version of the tower mill is the tent mill. In it, the stone tower was replaced by a wooden frame, usually octagonal in shape (there were mills with more or less angles). The frame was covered with straw, slate, roofing felt, sheet metal. This light-weight tent structure compared to tower mills made the windmill more practical, allowing mills to be erected in areas of unstable soil. Initially, this type was used as a drainage structure, but later the scope of use expanded significantly.

Of great importance in windmills has always been the design of the blades (sails). Traditionally, a sail consists of a frame-lattice, on which a canvas is stretched. The miller can independently adjust the amount of fabric depending on the strength of the wind and the required power.

In colder climates, the fabric was replaced with wooden slats, which prevented freezing. Regardless of the design of the blades, it was necessary to completely stop the mill in order to adjust the sails.

The turning point was the invention in Great Britain at the end of the 18th century. structure that automatically adjusts to the wind speed without the intervention of the miller. The most popular and functional sails were invented by William Cubitt in 1807. In these blades, the fabric was replaced by a mechanism of connected shutters.

In France, Pierre-Théophile Burton invented a system consisting of longitudinal wooden battens connected by a mechanism that allowed the miller to open them while the mill was turning.

In the twentieth century thanks to advances in aircraft construction, the level of knowledge in the field of aerodynamics has significantly increased, which led to a further increase in the efficiency of the mills by the German engineer Bilau and Dutch craftsmen.

Most windmills had four sails. Along with them, there were mills equipped with five, six or eight sails. They are most widespread in the UK, Germany and less frequently in other countries. The first mill canvas factories were in Spain, Portugal, Greece, Romania, Bulgaria and Russia.

A mill with an even number of sails had an advantage over other types of mills, because if one of the blades was damaged, the blade opposite to it could be removed, thereby maintaining the balance of the entire structure.

It should be noted that windmills were used for many industrial processes other than grain grinding, such as oilseed processing, wool dressing, dyeing and stone products.

The total number of windmills in Europe at the time of the greatest distribution of this type of device reached, according to experts, the number of about 200 thousand. But this figure is quite modest compared to about 500 thousand watermills that existed at the same time. Windmills proliferated in regions where there was too little water, where the rivers froze in winter, and also in the plains where the flow of rivers was too slow.

With the advent of the Industrial Revolution, the importance of wind and water as major industrial energy sources declined; eventually a large number of windmills and water wheels were replaced by steam mills and mills powered by internal combustion engines. At the same time, windmills were still quite popular, they continued to be built until the end of the 19th century.

In addition to windmills, there were also wind turbines - structures specially designed to generate electricity. The first wind turbines were built at the end of the 19th century. by Professor James Blyth in Scotland, Charles F. Brush in Cleveland, and Paul La Cour in Denmark.

There were also wind pumps. They were used to pump water in the territory of modern Afghanistan, Iran and Pakistan since the 9th century. The use of wind pumps became widespread throughout the Muslim world, and then spread to the territory of modern China and India. Windpumps have been used in Europe, especially in the Netherlands and the East Anglia areas of Great Britain, from the Middle Ages onwards, to drain land for agricultural or building purposes.

In 1738-1740. In the Dutch town of Kinderdijk, 19 stone windmills were built to protect the lowlands from flooding. They pumped water from an area below sea level to the Lek River, which flows into the North Sea. In addition to pumping water, windmills were used to generate electricity. Thanks to these mills, Kinderdijk became the first electrified city in the Netherlands in 1886.

It is also worth noting that in 1997 windmills were included in the UNESCO World Heritage List.

According to the site ru.beautiful-houses.net

Wind organ in Ulyanovsk

The description of the first device, which was set in motion by the power of faith, was left to us by Heron of Alexandria, a Greek mathematician and mechanic of the first century AD. However, it was not a mill at all, but a hydraulic musical organ designed for temples. Another ancestor for the mill can serve as a Buddhist prayer wheel. This device is a smooth or faceted drum that rotates either from the touch of a hand or from a breath of wind. Special prayers - mantras - are embedded in the drum, which are constantly repeated with the rotation of the prayer windmill. The oldest device of this kind was described by a Chinese pilgrim at the beginning of the fifth century AD.

Arab geographers of the fifth century described Persian mills, the blades of which were located on the paddle-wheel blades on a steamer. The main disadvantage of this design was that it can only work where the wind blows in one direction. Another type of mill - with a vertical axis of rotation, was known in China. The design of this windmill differs from the Persian device in that the Chinese mechanism used a freely rotating sail blade.

In medieval Europe, the need for new sources of energy was constantly growing. For a long time, water mills firmly held the leadership, but windmills appeared in those areas where there were severe winters and rivers could freeze.

The first documentary evidence of a European windmill with a horizontal rotor dates back to the 80s of the twelfth century. Almost simultaneously, these devices appeared in England and Normandy. Some researchers believe that the crusaders brought windmills from the east. The next, 13th century, became a true century of windmills. In Europe, the first mills began to operate, in which the entire building turned towards the wind. They have grown significantly in size. The wingspan reached nine meters, and the power of such mills was equal to the power of twenty-five horses, or three hundred people.

In lands where production grew rapidly, the number of windmills increased accordingly. Most of all, England and Flanders succeeded in this matter. The city of Ypres alone acquired 120 windmills. Windmills were especially effective where the constancy of the winds was maintained. For example, in the coastal expanses of Holland. Mills have become an integral feature of the Dutch landscape, as well as part of the history and culture of this country. Dutch mills ground wood to make paper, crushed oak bark used in leather production, ground spices brought by ships from the east, but of course, the main purpose of these windmills was to pump water from low-lying areas. Ninety percent of all mills were employed in this work. Their wings swirled day and night.

With the advent of the era of steam, and then electricity, the demand for wind energy dropped sharply. The mills gradually began to disappear.
In southern Europe, the wind innovation took root much more slowly. Since the time of the Roman Empire, there has been the practice of using water mills. The rivers did not freeze there, and there was no need for windmills.

Vertical mills are highly dependent on the direction of the wind, so they soon came up with a mill on a goat, or post. Such mills rested on a pillar supported by sticks, which made it possible to turn the entire mill barn, setting it up against the wind. But a fully rotating mill could not be very large and heavy. Then another design was born - a fixed tower with a rotating roof. Its top turned to expose the blades to the winds blowing from different directions. It was this technical innovation that could give the mill the appearance of a formidable giant, waving his arms, as Don Quixote saw it ...

Soon, mill progress went even further - in 1772, the Scottish inventor Andrew Meikle replaced the sails with automatically opening and closing shields, similar to blinds. With revolving roofs and self-adjusting wings, mills reached the pinnacle of technical excellence by the end of the 19th century. However, for all their progressiveness, the mills had a strange reputation. In the villages, they were placed, as a rule, outside the outskirts, outside the small human world, and this gave rise to suspicions about the millers in dealing with evil spirits. In 1779, the comic opera The Miller, the Sorcerer, the Deceiver and the Matchmaker, based on a libretto by the writer Alexander Oblesimov, was staged in St. Petersburg. Already in the first monologue, the hero-miller explains to the public that every mill must have a sorcerer.

Pushkin, as we remember, placed the windmill among other fantasies from Tatyana's dream. This windmill "squatting dances, and crackles and waves its wings" ...

Having become a symbol of technological progress in the late Middle Ages, the mill fell victim to this progress at the beginning of the twentieth century. However, by the end of the last century, the wind turbine was revived again, only now it converts the free energy of the wind into electrical energy. Very successful and all over the world.

17. MILL

The first tools for grinding grain into flour were a stone mortar and pestle. Some step forward in comparison with them was the method of grinding grain instead of crushing. People very soon became convinced that grinding flour turns out much better. However, it was also extremely tedious work. The big improvement was the transition from moving the grater back and forth to rotation. The pestle was replaced by a flat stone that moved across a flat stone dish. It was already easy to move from a stone that grinds grain to a millstone, that is, to make one stone slide while rotating on another. Grain was gradually poured into the hole in the middle of the upper stone of the millstone, fell into the space between the upper and lower stones and was ground into flour. This hand mill was most widely used in ancient Greece and Rome. Its design is very simple. The basis of the mill was a stone, convex in the middle. At its top was an iron pin. The second, rotating stone had two bell-shaped recesses connected by a hole. Outwardly, it resembled an hourglass and was empty inside. This stone was planted on the base. An iron strip was inserted into the hole. When the mill rotated, the grain, falling between the stones, was ground. Flour was collected at the base of the lower stone. Such mills were of various sizes: from small ones, like modern coffee grinders, to large ones, which were driven by two slaves or a donkey. With the invention of the hand mill, the process of grinding grain was facilitated, but still remained a laborious and difficult task. It is no coincidence that it was in the flour milling business that the first machine in history arose that worked without the use of the muscular strength of a person or animal. This is a water mill. But first, the ancient masters had to invent a water engine.

The ancient water-motors apparently developed from the watering machines of the Chadufons, with the help of which they raised water from the river to irrigate the banks. Chadufon was a series of scoops that were mounted on the rim of a large wheel with a horizontal axis. When the wheel was turned, the lower scoops sank into the water of the river, then rose to the top of the wheel and overturned into the chute. At first, such wheels were rotated by hand, but where there is little water, and it runs quickly along a steep channel, the wheel began to be equipped with special blades. Under the pressure of the current, the wheel rotated and drew water itself. The result was a simple automatic pump that does not require the presence of a person for its operation. The invention of the water wheel was of great importance for the history of technology. For the first time, a person has at his disposal a reliable, versatile and very easy to manufacture engine. It soon became apparent that the movement created by the water wheel could be used not only to pump water, but also for other needs, such as grinding grain. In flat areas, the speed of the flow of rivers is small in order to turn the wheel with the force of the impact of the jet. To create the necessary pressure, they began to dam the river, artificially raise the water level and direct the jet along the chute onto the wheel blades.

However, the invention of the engine immediately gave rise to another problem: how to transfer the movement from the water wheel to the device that should perform useful work for humans? For these purposes, a special transmission mechanism was needed, which could not only transmit, but also transform rotational motion. Solving this problem, the ancient mechanics again turned to the idea of ​​the wheel. The simplest wheel drive works as follows. Imagine two wheels with parallel axes of rotation, which are in close contact with their rims. If now one of the wheels begins to rotate (it is called the driver), then due to the friction between the rims, the other (slave) will also begin to rotate. Moreover, the paths traversed by the points lying on their rims are equal. This is true for all wheel diameters.

Therefore, a larger wheel will make, in comparison with a smaller one associated with it, as many times fewer revolutions as its diameter exceeds the diameter of the latter. If we divide the diameter of one wheel by the diameter of the other, we get a number that is called the gear ratio of this wheel drive. Imagine a two-wheel transmission in which the diameter of one wheel is twice the diameter of the other. If the larger wheel is driven, we can use this gear to double the speed, but at the same time, the torque will decrease by half. This combination of wheels will be convenient when it is important to get a higher speed at the exit than at the entrance. If, on the contrary, the smaller wheel is driven, we will lose output in speed, but the torque of this gear will double. This gear is useful where you need to "strengthen the movement" (for example, when lifting weights). Thus, using a system of two wheels of different diameters, it is possible not only to transmit, but also to transform the movement. In real practice, gear wheels with a smooth rim are almost never used, since the couplings between them are not rigid enough, and the wheels slip. This drawback can be eliminated if gear wheels are used instead of smooth wheels. The first wheel gears appeared about two thousand years ago, but they became widespread much later. The fact is that cutting teeth requires great precision. In order for the second wheel to rotate evenly, without jerks and stops, with uniform rotation of one wheel, the teeth must be given a special shape, in which the mutual movement of the wheels would be as if they were moving over each other without slipping, then the teeth of one wheel would fall into hollows of the other. If the gap between the teeth of the wheels is too large, they will hit each other and quickly break off. If the gap is too small, the teeth cut into each other and crumble. The calculation and manufacture of gears was a difficult task for ancient mechanics, but they already appreciated their convenience. After all, various combinations of gears, as well as their connection with some other gears, provided enormous opportunities for transforming movement. For example, after connecting a gear wheel to a screw, a worm gear was obtained that transmits rotation from one plane to another. Using bevel wheels, it is possible to transmit rotation at any angle to the plane of the drive wheel. By connecting the wheel with a gear ruler, it is possible to convert the rotational motion into translational, and vice versa, and by attaching a connecting rod to the wheel, a reciprocating motion is obtained. To calculate gears, they usually take the ratio not of the diameters of the wheels, but the ratio of the number of teeth of the driving and driven wheels. Often several wheels are used in the transmission. In this case, the gear ratio of the entire transmission will be equal to the product of the gear ratios of the individual pairs.

When all the difficulties associated with obtaining and transforming movement were successfully overcome, a water mill appeared. For the first time, its detailed structure was described by the ancient Roman mechanic and architect Vitruvius. The mill in the ancient era had three main components interconnected into a single device: 1) a motor mechanism in the form of a vertical wheel with blades rotated by water; 2) a transmission mechanism or transmission in the form of a second vertical gear; the second gear rotated the third horizontal gear - the pinion; 3) an actuator in the form of millstones, upper and lower, and the upper millstone was mounted on a vertical gear shaft, with the help of which it was set in motion. Grain poured from a funnel-shaped bucket over the top millstone.

The creation of a water mill is considered an important milestone in the history of technology. It became the first machine to be used in production, a kind of pinnacle reached by ancient mechanics, and the starting point for the technical search for Renaissance mechanics. Her invention was the first timid step towards machine production.