Drowned by the Great Depression: diesel-powered sailboat "Barbara". Rotary wind propulsors for ships Conclusions and prospects

Our friends and colleagues from the Hungarian magazine “Ezermester” offered to build this interesting model of a rotary yacht for their readers. Try to do it yourself.

An ordinary sail is familiar to everyone. The wind blows it, creating a driving force. And the rotor sail, which you see in the pictures, transmits force to the propeller, working like an engine. This sail has a drawback: a yacht model equipped with it cannot reach the same speed as with a conventional sail. But there are also advantages: firstly, there is no need to “catch the wind” by changing the position of the sail; secondly, the yacht sails almost the same at any angle to the wind and even directly against the wind.

The rotor is installed vertically on the yacht. Rotating under the pressure of the wind, he through the pole

the crank pair is driven by the propeller shaft.

Choose the design of the yacht hull yourself. The length of the vessel with the indicated rotor dimensions is no more than 700 mm. Do not hollow out the body from a single piece of wood - it will turn out too heavy. Make a light and durable frame and cover it with plywood veneer. Cover the inside of the veneer with paper (it will protect the plywood from cracking) and cover with waterproof varnish.

To prevent the yacht from capsizing, equip it with a weighted centerboard. Install the rudder at the stern - its position should be fixed.

Bend the rotor blades from millimeter balsa or plywood 0.6 mm thick. Make disks from plywood 1-1.5 mm thick. The rotor should rotate freely on a vertically mounted spoke.

After you manage to build and test a yacht with a rotor sail, try experimenting by changing the height and diameter of the rotor, the shape of its blades, and the size of the propeller. Perhaps you will be able to increase the speed of the yacht and improve its stability.

Useful juices

Plastic film can be joined like this: press two pieces of film between metal plates so that the edges protrude slightly, and draw a burning match. The seam is welded.

Your little brother, who is taking his first steps, has difficulty maintaining his balance on the slippery floor. Glue two thin strips of rubber along the foot to the soles of the booties - and the child can safely walk on the polished floor.

Insert a small permanent magnet into the back of the hammer handle. Now it will be easy for you to collect the scattered nails after finishing the work.

After two independent tests in the North Sea, Finnish company Norsepower, which designs and manufactures rotor sails for ships, has confirmed fuel savings of 5 to 20%. The technology is called Rotor Sail Solution and is an upgraded version of the Flettner rotor.

During operation of the turbosail, the cylinder rotates around its axis. The operation of an engine is based on a physical phenomenon in which the flow of air flowing around a rotating body creates additional force.


The company claims that the technology allows saving up to 20% of fuel per year, depending on weather conditions.

The first tests of rotor sails took place at the end of 2014. The vessel operated continuously between the Netherlands and Great Britain on the North Sea at a speed of 16 knots.


A technical research center in Finland collected data over a six-month period, during which time the rotor sail operated 99% of the time. The results confirmed that the rotor sail is capable of producing a large number of traction force, which provides significant fuel savings.

“The successful testing of our wind turbine is a groundbreaking moment not only for Norsepower, but also for more widespread development wind power technology for shipping. The findings suggest that when Norsepower technology is implemented at scale, it can produce up to 20% net fuel cost savings with a payback period of less than four years at current fuel prices, confirming that wind technologies are commercially viable solutions , which reduce

Blowing in a wind tunnel showed: this driving force can be increased almost 2 times if you cover the top of the cylinder with a disk (in the form of a flat plate), the diameter of which is larger than the diameter of the cylinder itself. In addition, it was important to find the necessary relationships between wind speed and the angular speed of rotation of the rotor. The magnitude of the force caused by rotation depends on this; That’s why the rotors were first tested in a wind tunnel and then on a model ship. The experiment made it possible to establish their optimal dimensions for an experimental vessel, and the name “Flettner rotor” has since been assigned to the unusual propulsion unit.

The battered three-masted schooner “Bukau” with a displacement of 980 tons was used as the first experimental vessel to test it. In 1924, instead of three masts, two rotor-cylinders with a height of 13.1 m and a diameter of 1.5 m were installed on it (hereinafter, see images of ships on the central spread of the magazine), They were driven by two 220 V DC electric motors. Electricity was generated by a small diesel generator with a capacity of 33 kW (45 hp).

The tests began in the Baltic and ended successfully. In February 1925, the ship left the Free City of Danzig, heading to England. In the North Sea, the Bukau had to contend with strong seas, but the schooner, due to proper reballasting, swayed less than ordinary ships. Fears that heavy rotors would negatively affect the stability of the vessel or would themselves suffer during rolling did not materialize; the wind pressure on their surface did not reach large values. At the same time, the weather was so bad that many ships of the same displacement as the Bukau sought refuge in nearby ports. “Not a single sailing ship could have completed the voyage that a rotary schooner had done,” wrote English newspapers.

The return journey to Cuxhaven was also accompanied by storms. This time

Fig.3. Change in speed (average values) of vessels: 1) with power plants (PP), 2) sailing and 3) with combined (sail and PP) propulsors.

The Bukau was loaded with coal along the waterline, and she once again showed her advantages over other sailing ships. Waves rolled over the deck and broke the lifeguard

body boat, but the rotors themselves did not receive any damage. Subsequently, the schooner was renamed “Baden-Baden” and she made another difficult voyage - after enduring a severe storm in the Bay of Biscay, she crossed Atlantic Ocean and arrived safely in New York.

The rotary propulsion system received high praise. It turned out to be easier to maintain than conventional sails required, it quickly entered operating mode, and therefore they decided to continue testing. In 1924, the first ship designed specifically for sailing with a rotary propulsion was laid down at the shipyard of the Weser joint-stock company (Germany). It was called "Barbara" and was intended to transport fruit from the ports of South America to Germany. With a length of 85, a width of 15.2 and a draft of 5.4 m, the ship had a cargo capacity of about 3000 tons. According to the initial project, it was supposed to have one giant rotor with a height of 90 m and a diameter of 13.1 m, but then, taking into account the experience of the schooner Bukau ", the colossal rotor was replaced by three smaller ones - 17 m high and 4 m in diameter. They were made of aluminum alloys with a wall thickness of slightly more than a millimeter. For each rotor there was one motor with a power of 26 kW (35 hp), developing 150 rpm. With a force 5 wind (8 - 11 m/s) in a favorable direction (heading angle 105 - 110 degrees), the thrust of the rotary propulsors was equivalent to the operation of an engine with a power of 780 kW (1060 hp). In addition, a 750 kW (1,020 hp) single-shaft diesel unit driving the propeller supplemented the rotor thrust, allowing the ship to sail at a speed of 10 knots (18.5 km/h).

At the beginning of 1926, the ship was delivered to the customer, and until the end of the year it transported fruit from Italy 8 to Germany - it was necessary to test the rotors in long-term operation. Since 1927, "Barbara" performed regular flights V South America, however, after three years, preference was still given to the diesel engine, replacing the rotors with them.

Being essentially sailing ships, ro

tow ships had enormous advantages over them. There was no need to call the crew on deck to clean and set the sails; only one officer (on the bridge) controlled the movement of the rotors using several handles. These ships sailed close-hauled - up to 30 degrees, whereas most conventional sailboats have an angle between the direction

The wind direction and direction of movement is at least 40 - 50 degrees. The travel speed was regulated by the speed of rotation of the rotors, and maneuvering was controlled by changing the direction of their rotation. Rotor ships could even reverse.

However, the complexity of the design of rotary propulsors, and most importantly the fact that the ships equipped with them continued to remain sailing ships with all the disadvantages, the first of which was complete dependence on the wind, did not lead to their widespread use.

However, despite all the disadvantages, designers returned again and again to the idea of ​​using wind energy.

In the mid-60s. In many maritime countries Special design bureaus were created that dealt with the problem of wind propulsion, that is, the movement of a vessel with the help of wind engines and wind propulsors. In the first case, the conversion of wind energy into thrust occurs along the chain: wind engine - transmission (mechanical or electrical) - propeller. By design, wind turbines are distinguished with a horizontal axis of rotation (1-2-3 or multi-blade turbine) and with a vertical axis, for example, a drum-type turbine; in terms of rotation speed - high-speed, having a high rotation speed (combines well with electric generators in terms of rotation frequency), and low-speed, creating a large torque directly on the propeller. When using a wind engine, the ship is not limited in choosing a course relative to the direction of the wind, however, the wind engine has low efficiency due to repeated energy conversion. The wind turbine is effective at wind speeds of 3 - 4< У, <12-14м/с, причем судно лучше двигается при встречных ветрах, нежели при попутных; при скорости ветра 15 - 20 м/с он должен быть остановлен, поскольку возникает угроза его разрушения,

Experimental wind turbines of various designs have been successfully tested on yachts. However, on large transport ships they are not used even as drives for electric generators, although experiments in this direction are being conducted.

In the second case, the traction force pulling the ship arises directly on the wind propulsion device, but sailing directly against the wind and in a certain range of heading angles near this direction is impossible; the speeds of such vessels depend on the wind speed and are relatively low - 7 - 10 knots (13 - 18.5 km/h). The main types of wind propulsors include the already known Flettner rotor, the wing-sail and the classic sail, which are still being improved, both in the creation of new materials and the implementation of the most effective projects, If on Viking ships, on Russian boats, caravels, barges, clipper ships used canvas sails, and some peoples, for example the Nivkhs living on Sakhalin and along the lower Amur, made sails from fish skin, but now, thanks to advances in chemistry, new materials with amazing properties have been created. Wrinkle-resistant lavsan and heat-resistant nitron appeared, and in 1977, industrial tests of plastics and synthetic fibers, characterized by increased strength and lightness, were carried out. It is these materials that are used for modern ships with sailing propulsion.

The first full-scale studies with wind turbines were carried out in 1960 - 1967. at the Hamburg Institute

TECHNOLOGY-YOUTH 2 9 8

The famous documentary series “The Underwater Odyssey of the Cousteau Team” was filmed by the great French oceanographer in the 1960s and 1970s. Cousteau's main ship was then converted from the British minesweeper Calypso. But in one of the subsequent films - "Rediscovery of the World" - another ship appeared, the yacht "Halcyone".

Looking at her, many TV viewers asked themselves the question: what kind of strange pipes are installed on the yacht?.. Maybe these are pipes from boilers or propulsion systems? Imagine your surprise if you find out that these are SAILS... turbosails...

The Cousteau Foundation acquired the yacht Alcyone in 1985, and this ship was considered not so much as a research ship, but as a basis for studying the effectiveness of turbosails - the original ship propulsion system. And when, 11 years later, the legendary Calypso sank, Alkyone took its place as the main ship of the expedition (by the way, today Calypso is raised and in a semi-looted state stands in the port of Concarneau).

Actually, the turbosail was invented by Cousteau. Just like scuba gear, an underwater saucer and many other devices for exploring the depths of the sea and the surface of the World Ocean. The idea was born in the early 1980s and was to create the most environmentally friendly, but at the same time convenient and modern propulsion device for waterfowl. The use of wind power seemed to be the most promising area of ​​research. But here’s the problem: mankind invented the sail several thousand years ago, and what could be simpler and more logical?

Of course, Cousteau and company understood that it was impossible to build a ship propelled solely by sail. More precisely, perhaps, but its driving performance will be very mediocre and dependent on the vagaries of the weather and wind direction. Therefore, it was initially planned that the new “sail” would be only an auxiliary force used to help conventional diesel engines. At the same time, a turbosail would significantly reduce diesel fuel consumption, and in strong winds it could become the only propulsion device of the vessel. And the team of researchers looked to the past - to the invention of the German engineer Anton Flettner, a famous aircraft designer who made a serious contribution to shipbuilding.

The turbosail is a hollow cylinder equipped with a special pump. The pump creates a vacuum on one side of the turbosail, pumping air into the sail, the outside air begins to flow around the turbosail at different speeds and the ship begins to move in a direction perpendicular to the air pressure. This is very reminiscent of the lift force acting on the wing of an airplane - the pressure is greater from below the wing and the airplane is pushed upward. The turbosail allows the ship to move against any wind, as long as there is enough pump power. Used as an auxiliary system for a conventional marine engine. Two turbosails installed on the ship of Cousteau’s team “Halcyon” allowed saving up to 50% of fuel.

Flettner rotor and Magnus effect

On September 16, 1922, Anton Flettner received a German patent for the so-called rotary vessel. And in October 1924, the experimental rotary ship Buckau left the slipways of the Friedrich Krupp shipbuilding company in Kiel. True, the schooner was not built from scratch: before the installation of Flettner rotors, it was an ordinary sailing vessel.

Flettner's idea was to use the so-called Magnus effect, the essence of which is as follows: when an air (or liquid) flow flows around a rotating body, a force is generated perpendicular to the direction of the flow and acts on the body. The fact is that a rotating object creates a vortex motion around itself. On the side of the object where the direction of the vortex coincides with the direction of the liquid or gas flow, the speed of the medium increases, and on the opposite side it decreases. The pressure difference creates a transverse force directed from the side where the direction of rotation and the direction of flow are opposite, to the side where they coincide.

“Flettner’s wind ship is on everyone’s lips thanks to unusually zealous newspaper propaganda,” wrote Louis Prandtl in his article about the development of the German engineer.

This effect was discovered in 1852 by the Berlin physicist Heinrich Magnus.

Magnus effect

German aeronautical engineer and inventor Anton Flettner (1885–1961) went down in maritime history as the man who tried to replace sails. He had the opportunity to travel for a long time on a sailboat across the Atlantic and Indian oceans. Many sails were installed on the masts of sailing ships of that era. Sailing equipment was expensive, complex, and aerodynamically not very efficient. Constant dangers awaited the sailors, who, even during a storm, had to deal with sails at a height of 40–50 meters.

During the voyage, the young engineer had the idea to replace the sails, which required a lot of effort, with a simpler but effective device, the main propulsion of which would also be the wind. While thinking about this, he remembered the aerodynamic experiments conducted by his compatriot, the physicist Heinrich Gustav Magnus (1802–1870). They found that when the cylinder rotates in the air flow, a transverse force arises with a direction depending on the direction of rotation of the cylinder (Magnus effect).

One of his classic experiments went like this: “A brass cylinder could rotate between two points; rapid rotation was imparted to the cylinder, as in a top, by a cord. The rotating cylinder was placed in a frame, which, in turn, could easily rotate. This system was exposed to a strong stream of air using a small centrifugal pump. The cylinder deviated in a direction perpendicular to the air stream and to the cylinder axis, moreover, in the direction in which the directions of rotation and the stream were the same” (L. Prandtl “The Magnus Effect and the Wind Ship”, 1925).

A. Flettner immediately thought that the sails could be replaced by rotating cylinders installed on the ship.

It turns out that where the surface of the cylinder moves against the air flow, the wind speed decreases and the pressure increases. On the other side of the cylinder, the opposite is true - the air flow speed increases, and the pressure drops. This difference in pressure on different sides of the cylinder is the driving force that makes the ship move. This is the basic principle of operation of rotary equipment, which uses the force of the wind to propel the vessel. Everything is very simple, but only A. Flettner “did not pass by,” although the Magnus effect has been known for more than half a century.

He began to implement the plan in 1923 on a lake near Berlin. Actually, Flettner did a rather simple thing. He installed a paper cylinder-rotor about a meter high and 15 cm in diameter on a meter-long test boat, and adapted a clock mechanism to rotate it. And the boat sailed.

The captains of sailing ships mocked A. Flettner's cylinders, which he wanted to replace the sails with. The inventor managed to interest wealthy patrons of the arts in his invention. In 1924, instead of three masts, two rotary cylinders were mounted on the 54-meter schooner Buckau. These cylinders were rotated by a 45 hp diesel generator.

The rotors of the Bukau were driven by electric motors. Actually, there was no difference in design from Magnus’s classical experiments. On the side where the rotor rotated towards the wind, an area of ​​high pressure was created, and on the opposite side, a region of low pressure. The resulting force moved the ship. Moreover, this force was approximately 50 times greater than the force of wind pressure on a stationary rotor!

This opened up enormous prospects for Flettner. Among other things, the area of ​​the rotor and its mass were several times smaller than the area of ​​the sail rig, which would provide equal driving force. The rotor was much easier to control, and it was also quite cheap to produce. From above, Flettner covered the rotors with plate-like planes - this approximately doubled the driving force due to the correct orientation of the air flows relative to the rotor. The optimal height and diameter of the rotor for the Bukau were calculated by blowing a model of the future vessel in a wind tunnel.

Cousteau's turbosailer - As of 2011, Alkyone is the only ship in the world with a Cousteau turbosail. The death of the great oceanographer in 1997 put an end to the construction of a second similar ship, Calypso II, and other shipbuilders are wary of the unusual design...

The Flettner rotor performed excellently. Unlike a conventional sailing ship, a rotary ship was practically not afraid of bad weather and strong side winds; it could easily sail on alternating tacks at an angle of 25º to the headwind (for a conventional sail the limit is about 45º). Two cylindrical rotors (height 13.1 m, diameter 1.5 m) made it possible to perfectly balance the vessel - it turned out to be more stable than the sailboat that the Bukau was before perestroika. Tests were carried out in calm conditions, in storms, and with deliberate overload - and no serious deficiencies were identified. The most advantageous direction for the movement of the ship was the direction of the wind exactly perpendicular to the axis of the ship, and the direction of movement (forward or backward) was determined by the direction of rotation of the rotors.

In mid-February 1925, the schooner Buckau, equipped with Flettner rotors instead of sails, left Danzig (now Gdansk) for Scotland. The weather was bad, and most sailing ships did not dare leave the ports. In the North Sea, the Buckau had a serious battle with strong winds and large waves, but the schooner heeled less than other sailing ships encountered.

During this voyage, it was not necessary to call crew members on deck to change sails depending on the strength or direction of the wind. All that was needed was one watch navigator, who, without leaving the wheelhouse, could control the activities of the rotors. Previously, the crew of a three-masted schooner consisted of at least 20 sailors; after it was converted into a rotary ship, 10 people were enough.

In the same year, the shipyard laid down its second rotary ship - the mighty cargo liner Barbara, driven by three 17-meter rotors. At the same time, one small motor with a power of only 35 hp was enough for each rotor. (at a maximum rotation speed of each rotor of 160 rpm)! The thrust of the rotors was equivalent to the thrust of a screw propeller coupled with a conventional ship diesel engine with a power of about 1000 hp. However, diesel was also present on the ship: in addition to the rotors, it drove the propeller (which remained the only propulsion device in case of calm weather).

Promising experiences prompted the shipping company Rob.M.Sloman from Hamburg to build the Barbara in 1926. It was planned in advance to equip it with turbosails - Flettner rotors. Three rotors with a height of about 17 m were mounted on a vessel with a length of 90 m and a width of 13 m.

"Barbara", as planned, successfully transported fruit from Italy to Hamburg for some time. Approximately 30–40% of the voyage was powered by the wind. With a wind of 4–6 points, “Barbara” developed a speed of 13 knots.

The plan was to test the rotary vessel on longer voyages in the Atlantic Ocean.

But in the late 1920s the Great Depression struck. In 1929, the charter company refused to continue leasing the Barbara and she was sold. The new owner removed the rotors and refitted the ship according to the traditional design. Still, the rotor was inferior to screw propellers in combination with a conventional diesel power plant due to its dependence on the wind and certain limitations on power and speed. Flettner turned to more advanced research, and the Baden-Baden eventually sank during a storm in the Caribbean in 1931. And they forgot about rotor sails for a long time...

The beginning of rotary ships seemed to be quite successful, but they were not developed and were forgotten for a long time. Why? Firstly, the “father” of rotary ships, A. Flettner, plunged into the creation of helicopters and ceased to be interested in maritime transport. Secondly, despite all their advantages, rotary ships have remained sailing ships with their inherent disadvantages, the main one of which is dependence on the wind.

Flettner rotors became interested again in the 80s of the twentieth century, when scientists began to propose various measures to mitigate climate warming, reduce pollution, and more rational fuel consumption. One of the first to remember them was the explorer of the depths, the Frenchman Jacques-Yves Cousteau (1910–1997). To test the operation of the turbosail system and reduce the consumption of increasingly expensive fuel, the two-masted catamaran “Alcyone” (Alcyone is the daughter of the wind god Aeolus) was converted into a rotary vessel. Having set sail in 1985, he visited Canada and America, rounded Cape Horn, and around Australia and Indonesia, Madagascar and South Africa. He was transferred to the Caspian Sea, where he sailed for three months, doing various research. Alcyone still uses two different propulsion systems - two diesel engines and two turbo sails.

Turbosail Cousteau

Sailboats were also built throughout the 20th century. In modern ships of this type, the sails are furled using electric motors, and new materials make the design significantly lighter. But a sailboat is a sailboat, and the idea of ​​using wind energy in a radically new way has been in the air since the time of Flettner. And it was picked up by the tireless adventurer and explorer Jacques-Yves Cousteau.

On December 23, 1986, after the Halcyone mentioned at the beginning of the article was launched, Cousteau and his colleagues Lucien Malavard and Bertrand Charrier received joint patent No. US4630997 for “a device that creates force through the use of a moving liquid or gas.” The general description is as follows: “The device is placed in an environment moving in a certain direction; in this case, a force arises acting in a direction perpendicular to the first. The device avoids the use of massive sails, in which the driving force is proportional to the sail area.” What is the difference between a Cousteau turbosail and a Flettner rotor sail?

In cross section, the turbosail is something like an elongated drop, rounded at the sharp end. On the sides of the “drop” there are air intake grilles, through one of which (depending on the need to move forward or backward) air is sucked out. To ensure maximum efficient suction of wind into the air intake, a small fan driven by an electric motor is installed on the turbo sail.

It artificially increases the speed of air movement on the leeward side of the sail, sucking in the air stream at the moment of its separation from the plane of the turbosail. This creates a vacuum on one side of the turbosail, while simultaneously preventing the formation of turbulent vortices. And then the Magnus effect acts: rarefaction on one side, as a result - a lateral force capable of causing the ship to move. Actually, a turbosail is an aircraft wing placed vertically; at least the principle of creating a driving force is similar to the principle of creating an aircraft lift. To ensure that the turbosail is always facing the most advantageous side to the wind, it is equipped with special sensors and installed on a turntable. By the way, Cousteau’s patent implies that air can be sucked out from inside the turbosail not only by a fan, but also, for example, by an air pump - thus Cousteau closed the gate for subsequent “inventors.”

In fact, Cousteau first tested a prototype turbosail on the catamaran “Windmill” (Moulin à Vent) in 1981. The catamaran's largest successful voyage was from Tangier (Morocco) to New York under the supervision of a larger expedition ship.

And in April 1985, the Halcyone, the first full-fledged ship equipped with turbosails, was launched in the port of La Rochelle. Now she is still on the move and today is the flagship (and, in fact, the only large ship) of the Cousteau team flotilla. The turbosails on it do not serve as the only propulsion, but they help the usual coupling of two diesel engines and
several screws (which, by the way, allows you to reduce fuel consumption by about a third). If the great oceanographer had been alive, he would probably have built several more similar ships, but the enthusiasm of his associates noticeably waned after Cousteau left.

Shortly before his death in 1997, Cousteau was actively working on the project of the Calypso II vessel with a turbosail, but did not have time to complete it. According to the latest data, in the winter of 2011, Alkyone was in the port of Kaen and was waiting for a new expedition.

And again Flettner

Today, attempts are being made to revive Flettner's idea and make rotor sails widespread. For example, the famous Hamburg company Blohm + Voss began active development of a rotary tanker after the oil crisis of 1973, but by 1986 economic factors closed down this project. Then there was a whole series of amateur designs.

In 2007, students at the University of Flensburg built a catamaran propelled by a rotor sail (Uni-cat Flensburg).

In 2010, the third ship in history with rotor sails appeared - the E-Ship1 heavy-duty truck, which was built for Enercon, one of the largest manufacturers of wind generators in the world. On July 6, 2010, the ship was launched for the first time and made a short voyage from Emden to Bremerhaven. And already in August he set off on his first working voyage to Ireland with a load of nine wind generators. The vessel is equipped with four Flettner rotors and, of course, a traditional propulsion system in case of calm weather and for additional power. Still, rotor sails serve only as auxiliary propulsion: for a 130-meter truck, their power is not enough to develop the proper speed. The engines are powered by nine Mitsubishi power units, and the rotors are driven by a Siemens steam turbine that uses exhaust gas energy. Rotor sails can save 30 to 40% of fuel at a speed of 16 knots.

But Cousteau’s turbosail still remains in some oblivion: Alkyone is currently the only full-size ship with this type of propulsion. The experience of German shipbuilders will show whether it makes sense to further develop the theme of sails powered by the Magnus effect. The main thing is to find an economic justification for this and prove its effectiveness. And then, you see, all world shipping will switch to the principle that a talented German scientist described more than 150 years ago.

In the North Sea in 2010, a strange ship “E-Ship 1” could be seen. On its upper deck there are four tall round chimneys, but smoke never billows from them. These are the so-called Flettner rotors, which replaced traditional sails.

The world's largest manufacturer of wind power plants, Enercon, launched a 130-meter-long, 22-meter-wide rotary vessel, which was later named E-Ship 1, at the Lindenau shipyard in Kiel on August 2, 2010. It was then successfully tested in the North and Mediterranean seas, and is currently transporting wind generators from Germany, where they are produced, to other European countries. It reaches a speed of 17 knots (32 km/h), simultaneously transports more than 9 thousand tons of cargo, its crew is 15 people.

Singapore-based shipbuilding company Wind Again, which creates technologies to reduce fuel consumption and emissions, proposes to install specially designed Flettner rotors (folding) on ​​tankers and cargo ships. They will reduce fuel consumption by 30–40% and will pay for themselves in 3–5 years.

Finnish marine engineering company Wartsila is already planning to install turbosails on cruise ferries. This is due to the desire of the Finnish ferry operator Viking Line to reduce fuel consumption and environmental pollution.

The use of Flettner rotors on pleasure boats is being studied by the University of Flensburg (Germany). Rising oil prices and an alarming warming climate appear to be creating favorable conditions for the return of wind turbines.

The yacht designed by John Marples, Cloudia, is a rebuilt Searunner 34 trimaran. The yacht underwent its first tests in February 2008 in Fort Pierce, Florida, USA, and its creation was financed by the Discovery TV channel. “Claudia” showed itself to be incredibly maneuverable: it stopped and reversed in a matter of seconds, and moved freely at an angle of about 15° to the wind. The noticeable improvement in performance compared to the traditional Flettner rotor is due to the additional transverse discs installed on the front and rear rotors of the trimaran.

Apparently, a phenomenon has appeared in technical creativity that can roughly be called bottle modeling. The fact is that modelers of various directions are increasingly using... plastic bottles. From these light and at the same time durable vessels, they make beautiful hulls for models of yachts and catamarans, compressed air cylinders for driving air engines of aircraft and car models. Thin transparent plastic has become an ideal material for making lanterns for airplane models.

And here is another model, the design of which uses plastic vessels. This is a catamaran with an original rotary wind propulsion system.

To begin with, a few words about how the rotor generates a driving aerodynamic force. It has long been noted that if you place a rotating cylinder in an air flow, then a force perpendicular to the direction of the flow will act on the cylinder. The fact is that when the cylinder rotates, the direction of movement of one of the parts of its surface coincides with the direction of air flow, and the rotation of the opposite part coincides with it.

In accordance with Bernoulli's law, which establishes the correspondence between the speed of air flow and the pressure in it, as the flow speed increases, the pressure in it decreases. When blowing a rotating cylinder in a zone with counter-movement of the cylindrical surface and flow, the pressure is less than in the zone with co-movement of the cylindrical surface and air. The appearance of a pressure difference causes the formation of a force directed perpendicular to the movement of the air flow from a zone of higher pressure to a zone of lower pressure.

Attempts have been made from time to time to use rotors to drive ships. One of the most successful is the propulsion unit installed on Jacques-Yves Cousteau's research vessel Calypso. Rotating cylinders mounted in the center plane of the vessel allow saving a lot of fuel on ocean crossings.

1 - bridge cross member (plywood s15.2 pcs.); 2- bridge platform (pine, slats 60×15); 3 - rotor housings; 4-front part of the catamaran model hull; 5 - keel; 6 - rear part of the hull of the catamaran model; 7 - steering device; 8- washers; 9 - M5 bolt; 10 - spacer washer (rubber); 11 - M5 nut; 12,17,21,22 - wide washers (steel); 13 - valve nut (2 pcs.); 14 - valve with spool (from the bicycle inner tube); 15-thread plug; 16-sealing washer (rubber); 18 - spacer sleeve (duralumin); 19 - bearing (2 pcs.); 20 - rotor shaft (steel); 23 - M6 nut; 24 - bearing housing (duralumin)

It should be noted that the rotors on the Calypso are spun by a small auxiliary motor. However, devices driven by air flow also show good results.

In the proposed catamaran model, the rotors are also spun by air flow. Each of the rotors is a plastic bottle, on the surface of which there are many blades - when blown, such a bottle, mounted vertically on bearings, receives axial rotation.

However, it makes sense to start making a catamaran with the hulls - each will require two one and a half or two liter bottles. Plastic vessels into a single body are joined at the bottoms and connected with an M5 bolt, nut and washers - two steel and one rubber. This connection turns out to be very rigid and ensures absolutely accurate alignment. The fact is that the bottom protrusions of one vessel fall into the depressions of another.

For such a connection, special tools are required - a screwdriver with an extended blade and a long socket wrench. To insert fasteners inside the bottles, a bolt, nut and washer can be glued to the tools with ordinary plasticine.

1 - overlay (birch, strip 12×10, 2 pcs.); 2 - plate (plywood s5)

Rotor housing(rotor base is a plastic bottle with a capacity of 1.5 or 2 l)

Valves from bicycle inner tubes are inserted into the corks of all four bottles; with their help, the bodies are secured with nuts to the crossbars of the bridges. In addition, through the valves, you can use a regular bicycle pump to create excess air pressure inside the housings, which significantly increases their rigidity.

The hulls prepared in this way are mounted into a single catamaran using a bridge consisting of a platform (pine board with a cross-section of 60×15 mm) and two cross members (plywood 15 mm thick). The bridge parts are connected with long screws with a diameter of 4 mm. Holes for valves are drilled in the crossbars. The finished bridge is sanded, painted and covered with two or three layers of parquet varnish.

The keel of the catamaran is cut out of 5 mm thick plywood, and two birch blocks are glued to its upper part with epoxy resin. The front part of the keel is rounded, the rear part is ground into a wedge. The finished keel is sanded and coated with two layers of parquet varnish. If necessary, if the stability of the catamaran is insufficient, a lead bulb can be hung on the end of the keel. Fastening the keel to the bridge platform with four screws with a diameter of 4 mm.

The steering device of the catamaran consists of a plywood rudder and a tiller axle. The latter is bent from 4 mm steel wire and an M4 thread is cut at one end. The tail feather has a symmetrical profile with a rounded front and pointed trailing edges. The finishing of the feather is standard: sanding, painting and coating with parquet varnish.

The connection between the feather and the tiller axle is one-piece - using epoxy glue. However, if it is necessary to periodically disassemble the catamaran, then when gluing the axle into the feather, the threads on it should be coated with a thin layer of grease. Once the resin has cured, the axle will be easy to unscrew from the pen. Fastening the steering device to the bridge platform with a pair of nuts and washers.

And now the main thing is the manufacture of a rotary propulsion unit. As already mentioned, each of the rotors is a one-and-a-half or two-liter plastic bottle hinged on a platform with many bent blades on the surface. When blown by an air flow, such a rotor begins to rotate. To ensure that the blades are uniform and neat, it is advisable to use an electric burner or a homemade electric thermal cutter as a working tool for cutting through the wall of the rotor bottle.

1 - cutting part (nichrome, d0.5 wire); 2 - porcelain block (from the lamp socket); 3 - handle (from a file); 4 - connecting two-wire cord

Steering gear:

1 - tiller axis (steel, d4 wire); 2- bridge platform; 3 - M4 nuts; 4 - steering feather (plywood s6); 5 - washers

The latter is easy to assemble from a wooden handle from a file, a porcelain block from an incandescent lamp socket and nichrome wire with a diameter of 0.5 mm. The instrument is powered by LATR. The voltage should provide such heating of the nichrome wire that the plastic only melts, but in no case burns.

It is advisable to mark the contours of the blades on the surface with a thin felt-tip pen according to a template - a tin plate with a window cut into it according to the size of the blade. Before cutting, it makes sense to melt a couple of holes in the window, and then make slits along the contour of the blade. It should be noted that you need to work with a thermal cutter in a well-ventilated area - preferably near an open window. On a rotor prepared in this way, the blades are bent by approximately 35°.

The rotor hinge units must ensure their rotation is extremely easy - literally, from the slightest breeze. This can only be done using ball bearings. For two-liter bottles, bearings with diameters of 18 (external) and 6 (internal) mm and a width of 6 mm are quite suitable.

To secure the bearings in the neck of the bottle, you need a duralumin housing; in the neck it is fixed with a standard bottle cap with a hole with a diameter of 8 mm. The stepped roller on which the bearings and, accordingly, the rotor rotate is made of steel; it is secured to the bridge platform with an M6 nut. To ensure easy rotation of the rotor, before installing the bearings in the housing, remove the grease from them (rinse the bearings in kerosene) and apply machine oil intended for sewing machines.

During sea trials, a properly adjusted catamaran's rotary propulsion unit easily spins, and the boat, oriented sideways to the wind, quickly picks up speed, automatically maintaining a course relative to the direction of the wind. If the model is driven or falls, it is necessary to shift the center of lateral resistance by moving the keel forward or backward.

It should be noted that a rotary catamaran can sail not only on a gulfwind course, when the wind blows directly on board, but also on fuller or sharper courses. Although, of course, a catamaran with a classic sail is able to sail somewhat steeper into the wind.