How rpd works. With sealing flaps and reciprocating movements

17.04.2019

Internal combustion engine - brilliant invention humanity. Thanks to the internal combustion engine, technical progress began to develop significantly. There are several types of these settings. But the most famous are connecting rod and piston and rotary piston. The latter was invented by the German engineer Wankel in collaboration with Walter Freude. This power unit has a different device and principle of operation, when compared with the classic connecting rod-piston internal combustion engine. What is the principle of operation of the Wankel engine and why has this internal combustion engine not become so popular? All this we will consider in our today's article.

Characteristic

So what is this motor? This is an internal combustion engine that was developed by Felix Wankel in 1957. The function of the piston in this unit was performed by a three-vertex rotor. He made rotational movements inside a cavity of a special shape.

After a number of experimental models of motorcycles and cars, which occurred in the 70s of the last century, the demand for the Wankel engine decreased significantly. Although today a number of companies are still working on improving this internal combustion engine. So, you can meet the Wankel engine on the Mazda PX series. Also, this unit has found its application in modeling.

Wankel engine device

This power unit consists of several components:

Housings (stator).
combustion chambers.
inlet and outlet windows.
Fixed gear.
gear wheel.
Rotor.
Vala.
Spark plug.

What is the working principle of the Wankel engine? We will consider this below.

Principle of operation

This ICE operates in the following way. The rotor, mounted on an eccentric shaft through bearings, is driven by the force of gas pressure, which was formed as a result of the combustion of the air-fuel mixture. The motor rotor relative to the stator through a pair of gears. One of them ( big size) is located on the inner surface of the rotor. The second (support) is smaller and is tightly attached to the side cover of the engine. Through the interaction of the gears, the rotor produces eccentric circular motions. Thus, its edges are in contact with the inner surface of the combustion chamber.

As a result, several isolated chambers of variable volume are formed between the motor housing and the rotor. Their number is always 3. In these chambers, the process of mixture compression, its combustion, expansion of gases (which subsequently put pressure on the working surface of the rotor) and their removal takes place. As a result of the ignition of the fuel, the rotor is driven, transferring torque to the eccentric shaft. The latter is mounted on bearings and then transfers power to the transmission units. And only then the moment of forces of the Wankel engine goes to the wheels according to the classical scheme - through a cardan drive and axle shafts to the hubs. Thus, several mechanical pairs work simultaneously in a rotary motor. The first is responsible for the movement of the rotor and consists of several gears. The second de converts the movement of the rotor into revolutions of the eccentric shaft.

The gear ratio of the stator (housing) and gears is always stable and is 3:2. Thus, the rotor has time to rotate for a full revolution of the shaft by 120 degrees. In turn, for a full revolution of the rotor, internal combustion is produced in each of the three chambers formed by the faces.

Advantages

What are the advantages of this ICE? Wankel has a simpler design than the connecting rod and piston. So, the number of parts in it is 40 percent less than in a piston four-stroke internal combustion engine. But still, it is not possible to create a Wankel engine with your own hands without sophisticated equipment. After all, the rotor has a very complex shape. Those who tried to make a Wankel with their own hands suffered numerous failures.

But let's move on to the benefits. In the design of the rotary unit there is no crankshaft, gas distribution mechanism. Also, there are no connecting rods and pistons. The combustible mixture enters the chamber through the inlet window, which is opened by the edge of the rotor. And the exhaust gases at the end of the working cycle are released from the body through the exhaust port. Again, the role of the valve here is performed by the edge of the rotor itself. Also, there is no camshaft in the design (of which several are now used on connecting rod units). The Wankel rotary piston engine, according to the principle of operation of the gas distribution mechanism, is similar to a two-stroke one.

Special mention should be made of lubrication system. In fact, it is absent in the Wankel rotary engine. But how then do friction pairs work? It's simple: oil is added to the combustible mixture itself (as in primitive motorcycle engines). Thus, the lubrication of rubbing parts is carried out by the air-fuel mixture itself. The design does not have an oil pump familiar to everyone, which takes the lubricant from the sump and sprays it under special pressure.

Another advantage of the Wankel engine is its light weight and size. Since almost half of the parts that are mandatory in piston engines are missing here, the rotary unit is more compact and can fit in any engine compartment. compact dimensions allow you to use the space of the engine compartment more rationally, as well as provide a more uniform load on the front and rear axles (after all, in cars with conventional engines, more than 70 percent of the load falls on the front part). And due to the low weight, high stability is achieved. So, the engine has a minimum level of vibration, which has a positive effect on the comfort of the car.

The next plus of this unit is the high specific power, which is achieved at high shaft speeds. This feature allows you to achieve good technical characteristics. This is why the Wankel engine is used in Mazda sports cars. The motor easily spins up to seven or more thousand revolutions. At the same time, it provides much more torque and power at a small volume. All this has a positive effect on the accelerating dynamics of the car. For example, you can take the car "Mazda RX-8". With a volume of 1.3 liters, the engine produces 210 Horse power power.

Design flaws

Considering the device and principle of operation of the Wankel rotary engine, it is worth noting the main design flaw. This is the low efficiency of the gap seals between the combustion chamber and the rotor. The latter has a rather complex shape, which requires reliable sealing not only along the edges (of which there are four in total), but also along the side surface (which are in contact with the engine cover). At the same time, they are made in the form of steel spring-loaded strips with particularly precise processing both from the ends and from the working surfaces. All allowances for expansion during heating, incorporated in the design, degrade these characteristics. Because of this, it is impossible to avoid the breakthrough of gases in the end places of the sealing plates. In piston engines, the labyrinth effect is applied. So, the design uses three sealing rings with gaps in different sides.

But it is worth noting that in last years seal quality has improved. The designers have improved the Wankel engine, using new materials for seals. But still, gas breakthrough is considered the weakest point in a rotary internal combustion engine.

Oil consumption

As we said earlier, there is no lubrication system as such in this engine. Due to the fact that the oil enters along with the combustible mixture, its consumption increases significantly. And if on connecting rod engines natural lubricant leakage is excluded or is no more than 100 grams per 1 thousand kilometers, then on rotary engines this parameter ranges from 0.4 to 1 liter per thousand kilometers. This is because a complex sealing system requires more effective lubrication of the surfaces. Also, due to the high oil consumption, these motors cannot meet modern environmental standards. IN exhaust gases cars with a Wankel engine contain many dangerous to the body and environment substances.

Besides, rotary motor could only work on high-quality and expensive oils. This is due to several factors:

Tendency of contacting parts of the motor chamber and rotor to high wear.
Tendency of friction pairs to overheat.

On the use of RPD in the automotive industry

This engine gained the greatest popularity in the late 60s and early 70s of the last century. The Wankel RPD patent has been acquired by 11 leading automakers. So, in the 67th year, NSU developed the first business-class car with a rotary engine, which was called the NSU RO 80. This model mass-produced for 10 years. In total, more than 37 thousand copies were released. The car was popular, but the shortcomings of the rotary engine eventually tarnished the reputation of this car. Against the background of other NSU models, the NSU RO 80 sedan was the most unreliable. The mileage before the overhaul was only 50 thousand with the declared 100.

Also, the Peugeot-Citroen concerns, the Mazda company and the VAZ plant experimented with rotary engines (we will talk about this case separately below). The greatest success was achieved by the Japanese, releasing a car with a rotary engine in the 63rd year. On this moment the Japanese still equip RPDs on their RX series sports cars. To date, they have been freed from many of the "childhood diseases" that were inherent in the RPD of that time.

RPD Wankel and the motorcycle industry

In the 70s and 80s of the last century, some motorcycle manufacturers experimented with rotary engines. These are Hercules and Suzuki. Now mass production of rotary motorcycles has been established only at Norton. This brand produces NRV588 sportbikes equipped with two-rotor engines with a total volume of 588 cubic centimeters. The power of the Norton bike is 170 horsepower. with a curb weight of 130 kilograms, this motorcycle has excellent dynamic performance. Additionally, these RPDs are equipped with an electronic fuel injection system and a variable intake tract.

Data power units widely used among aircraft modellers. Since there are no requirements for efficiency and reliability in the model internal combustion engine, the production of such motors turned out to be inexpensive. In such internal combustion engines, there are no rotor seals at all, or they have the most primitive design. The main advantage of such an aircraft model unit is that it is easy to install it in a flying aircraft. scale model. ICE is light and compact.

Another fact: Felix Wankel, having received a patent for RPD in 1936, became the inventor of not only rotary engines, but also compressors, as well as pumps that operated in the same way. Such units can be found in repair shops and in production. By the way, portable electric pumps for pumping tires, cars are arranged exactly according to this principle.

RPD and VAZ cars

During Soviet times, they were also engaged in the creation of a rotary piston engine and its installation on domestic cars VAZ. So, the first RPD in the USSR was the VAZ-311 engine with a capacity of 70 horsepower. It was created on the basis of the Japanese unit 13V. But since the creation of the motor was carried out according to unrealistic plans, the unit turned out to be unreliable after being put into mass production. The first car with this engine was the VAZ-21018.

But the story of installing the Wankel engine on the VAZ does not end there. The second in a row was the VAZ-415 power unit, which was used in small batches on the G8 in the 80s. This power unit had better specifications. Power with a volume of 1308 cubic centimeters increased to 150 horsepower. Thanks to this, the Soviet VAZ-2108 with a rotary engine accelerated to hundreds in 9 seconds. And the maximum speed was limited to 190 kilometers per hour. But this engine was not without flaws. In particular, it is a small resource. He barely reached 80 thousand kilometers. Also among the minuses it is worth noting the high cost of creating such a car. Oil consumption was 700 grams for every thousand kilometers. Fuel consumption is about 20 liters per hundred. Therefore, the rotary unit was used only on special services vehicles, in small batches.

Conclusion

So, we found out what the Wankel engine is. This rotary unit is now used in series only on Mazda cars, and only on one model. Despite numerous improvements and attempts by Japanese engineers to improve the design of the RPD, it still has a rather small resource and is characterized by high oil consumption. Also, the new 1.3-liter Mazdas do not differ in fuel efficiency. All these shortcomings of the rotary motor make it impractical and little used in the automotive industry.

The only commercially produced rotary motor model to date is the Wankel engine, which belongs to the type of rotary motors with planetary circular motion of the main working element. Such a constructive layout of a rotary engine is undoubtedly the simplest in terms of its technical design, but not the most optimal in terms of the way of organizing work processes and therefore has its own inherent and serious drawbacks.

There are quite a lot of varieties of rotary engines with planetary movement of the main working element, but in essence they differ from each other only in the number of rotor faces and the corresponding shape of the inner surface of the housing. The given schemes different layouts similar motors are taken from the book "Marine Rotary Engines", edition of 1967, authors E. Akatov, V. Bologov and others and prepared for publication in in electronic format the author of this site.

Let's take a brief look at the very design of this type of engine, along with the history of its appearance and scope. The history of the creation of rotary engines with planetary rotational movement of the main working element begins in 1943, when the inventor Mylar proposed the first such scheme. Then, within a short time, several more patents were filed for engines of a similar design. Including the developer of the German company NSU - V. Frede. But the main weak point of this rotary engine scheme was the sealing system between the ribs at the junction of adjacent faces of the rotating triangular rotor and the walls of the stationary housing. R. Wankel, as a specialist in seals, was involved in solving this complex engineering problem. Soon, thanks to his energy and engineering thinking, he became the leader of the development team. In 1957, a prototype rotary engine of the DKM type was built in the NSU laboratory, with a triangular rotor and a capsule-shaped working chamber in which the rotor was stationary and the housing rotated around it. Much more practical was the KKM-type layout with a normal layout - the working chamber in the housing was stationary, and the rotor rotated in it. This motor appeared a year later, in 1958. In November 1959, NSU officially announced the creation of a working rotary engine. In a short time, about 100 companies around the world have acquired licenses for this technology, with 34 of them being Japanese.

The motor turned out to be very small, powerful and had few parts. In Europe, sales of cars with rotary engines began, but as it turned out, they had a small motor resource, they consumed a lot of fuel and had a very toxic exhaust. The oil crisis of 1973 due to another Arab-Israeli war, when gasoline prices increased several times, sharply raised the question of the efficiency of car engines. Because of this, in Europe and America, attempts to bring the Wankel rotary engine to the desired degree of perfection were discontinued. And only the Japanese company Mazda stubbornly continued to work in this direction. And also the Soviet VAZ plant - since gasoline at that time in the USSR cost a penny, and a powerful, albeit with a small resource, engine was needed law enforcement agencies. But in 2004, small-scale production at VAZ was closed and today Mazda is the only automaker that mass-produces cars with a rotary engine. Currently, only one car with a Wankel rotary engine is mass-produced in the world - this is the Mazda RX-8 sports coupe. This machine is equipped with a RENESIS engine with two rotor sections with a total volume of 1.3 liters. The engine is available in several versions with power from 200 to 250 hp.

After a brief review of the history of a rotary engine with a planetary motion of the rotor, let's dwell on the consideration of its advantages and disadvantages. ADVANTAGES of the Wankel rotary engine compared to traditional piston engines: 1) Increased specific power (hp / kg), it is almost twice that of piston 4 stroke engines. The mass of unevenly moving parts in the Wankel engine is much less than in piston engines of similar power, and the amplitude of such unbalanced movements is noticeably smaller. This is due to the fact that in the "piston" reciprocating movements are carried out, and in the Wankel engine - rotational, planetary circuits. In addition, the Wankel engine lacks a crankshaft and connecting rods.

The fact that such a single-rotor design engine produces power for three-quarters of each revolution of the output shaft also plays into the increased power of the Wankel. Unlike a single cylinder 4 stroke piston engine which only delivers power for one quarter of each revolution of the output shaft. It is for these reasons that much more power is removed from the unit volume of the combustion chamber in the serial Wankel rotary engine. With a working chamber volume of 1300 cm 3, the Mazda RX-8 has a power of 200 hp - 250 hp, and the previous Mazda model RX-7, with an engine of the same size, but with a turbocharger, produced 350 hp.

That is why a special feature of the Mazda RX is its excellent dynamic performance:

in low gear, it is possible to accelerate the car above 100 km / h without undue load on the engine at higher engine speeds (8000 rpm or more).
the Wankel engine is much easier to mechanically balance and get rid of vibration, which makes it possible to increase the comfort of light vehicles such as microcars;
the overall dimensions of a rotary piston engine are 1.5-2 times smaller in relation to a piston engine of comparable power.

The Wankel engine has 35-40% fewer parts.

Flaws:

1) The short stroke length of the face of the triangular rotor. Although it is difficult to compare these indicators directly with a piston motor - the types of piston and rotor movements are too different, but the Wankel engine has about a fifth less stroke length. There is one fundamental difference between the Wankel and the piston engine - the “piston” has an increase in volume in the direction of one linear direction, which coincides with the direction of the stroke. But for Wankel, this movement is complex and only part of the trajectory of the triangular rotor with planetary movement becomes the actual line of the working stroke. (FIG.) This is why the Wankel engine has poorer fuel efficiency than piston engines. Therefore, due to the short stroke length, the temperature of the exhaust gases is very high - the working gases do not have time to transfer their main pressure to the rotor, as the exhaust window and hot gases already open high pressure with volumetric fragments that have not yet stopped burning working mixture out into the exhaust pipe. Therefore, the exhaust gas temperature of the Wankel engine is very high.

2) The complex shape of the "crescent" combustion chamber. Such a combustion chamber has a large surface of contact of gases with the walls of the housing and the rotor. Therefore, a significant part of the heat is spent on heating the engine parts, and this reduces thermal efficiency and increase the temperature of the motor. In addition, this form of the combustion chamber leads to a deterioration in mixture formation and a slowdown in the combustion rate of the working mixture. Therefore, the Mazda RX-8 engine has 2 spark plugs on one rotor section. These features also negatively affect the level of thermodynamic efficiency.

3) Potentially low torque for a rotary motor. In order to remove rotation from a moving rotor, the center of rotation of which itself continuously performs planetary rotation along a circular path around the geometric center of the working chamber, this engine uses disks eccentrically located on the main shaft. In fact, these are elements of a crank device. That is, the Wankel engine could not completely get rid of the main drawback of the classic piston internal combustion engines - the crank - connecting rod mechanism. Although it is presented in the Wankel motor in its lightweight version - in the form of an eccentric shaft, but the main flaws of this mechanism: a torn, pulsating torque mode and a small arm of the main element that perceives torque - remained “not cured”. (FIG.) That is why a single-section Wankel is inefficient and you need to make 2 or 3 rotor sections to obtain normal performance, it is also desirable to put an additional flywheel on the shaft. In addition to the presence in the Wankel engine crank mechanism, the torque, which is small for a rotary engine, is also affected by the fact that the kinematic scheme of such a motor is very irrational in terms of perception by the surface of the rotor of the pressure of the working expansion gases. Therefore, only a certain part of the pressure - about a third - is translated into the working rotation of the rotor and creates a torque. We'll talk more about torque in a special section of the site.

For details on the principle of torque generation in a Wankel rotary engine, see the TORQUE page of the website.

4) The presence of vibrations in the body. The fact is that the system of a rotary motor with a planetary movement of the working element implies a non-equilibrium movement of this body. Those. during rotation, the center of mass of the rotor performs a continuous rotational movement around the center of mass of the body and the radius of this rotation is equal to the shoulder of the eccentric of the main motor shaft. That is why a constantly rotating force vector acts on the motor housing from the inside, equal to the centrifugal force that occurs on the rotor. That is, the rotor, when rotating on an eccentric shaft rotating in turn, has inevitable and pronounced elements of oscillatory motion in the nature of its movement. Which leads to the inevitability of vibrations. (RICE.)

5) Rapid wear of the mechanical radial seals at the corners of the rotor triangle, as they are subjected to a strong radial load, which is inevitable in the Wankel engine by its very principle of operation. (RICE.)

6) The constant threat of a breakthrough of high-pressure gases from the cavity of one working cycle to the cavity of another cycle. This is because the contact of the radial seal between the rotor fin and the combustion chamber wall occurs in one thin line. At the same time, there is still the problem of gas breakthrough through the plug installation sockets when the rotor rib passes over them.

7) Sophisticated lubrication system of the rotating rotor. In the Mazda RX-8 engine, special nozzles inject oil into the combustion chambers to lubricate the rotor fins rubbing against the walls of the combustion chamber during rotation. This increases the toxicity of the exhaust and at the same time makes the engine very demanding on the quality of the oil. In addition, at high speeds, there are increased requirements for lubrication of the cylindrical surface of the eccentric part of the main shaft, around which the rotor rotates, and which removes the main force from the rotor and translates into shaft rotation. It was these two technical difficulties, which are very difficult to solve, that led to insufficient lubrication at high speeds of the most friction-loaded parts of such an engine, and this, accordingly, sharply reduced the engine's engine life. It was the insufficient solution of such technical problems that led to a very small resource of Wankel engines, which were produced by the domestic AvtoVAZ. (FIG. - indicate the cylindrical contact surface of the inner socket of the rotor and the eccentric of the shaft disk)

8) High demands on the accuracy of the execution of parts of complex shape make such a motor difficult to manufacture. Such production requires high-precision and expensive equipment - machines capable of creating complex volumes of a working chamber with a curved epitrochoidal surface. The rotor itself also has the shape of a complex triangle with convex surfaces.

As can be seen from the content of this section of the site, the Wankel rotary engine has pronounced advantages, and a large number of almost insurmountable shortcomings that did not allow this type of engine to displace piston engines from the arsenal of modern technology. Although such prospects were seriously discussed in the late 60s and early 70s of the last century, and opinions were expressed in analytical reviews that by the end of the 80s of the 20th century, more than half of the world's cars will already have rotary engines of various types .... And, despite the presence of negative features and technical difficulties, the Wankel rotary engine could appear technically and take place as a commercially viable type of product, because the shortcomings of its main competitors - piston engines with crank - connecting rod mechanisms are even more serious and numerous. And this, despite over a century of attempts to improve them.

CONTINUED ABOUT WANKEL ROTARY ENGINE

September 2016 One of the most difficult problems of all types of rotary engines is the creation effective system seals, which should create a closed volume in the working chambers of a rotary engine. So far, this is one of the main difficulties in the Tverskoy-type scheme. There it is necessary to make an effective and difficult to manufacture sealing system. And in order to train my hand and get positive experience in such a matter, I decided to create a small working copy of the Wankel engine right from scratch. The work is already coming to an end - I am attaching a photo of such a motor.

Seals

The approximate power of one such rotor section is expected to be about 35-40 hp. A motor of 2 rotor sections is expected to have a power of 70-80 hp.

WANKEL ENGINE - DECEMBER
December 25, 2016 The production of the small Wankel is proceeding at an optimal pace. The engine is ready for 95%, small details remain.
Since on some sites on the Internet these photos of mine are already being discussed and a lot of fantasies are being wound around them, I inform you.
The engine was created from ZERO, there is not a single part from foreign models in it. It does not contain parts from Sachs Wankel, which have not been produced for 30 years, nor from modern small modern aixro, etc., etc.
The engine housing is made of structural alloyed heat-resistant steel subjected to thermochemical hardening. The hardness of the surface layer is 70 HRC. The depth of the heat-strengthened layer averages 1.5 mm. air cooling, oil for lubrication will be supplied to the compression chamber through 2 special nozzles. Those. there will be no need to mix oil with gasoline as in 2-stroke engines.

The engine was put on a lathe and subjected to a cold break-in for several hours. This made it possible to evaluate the operation of the seals and the tightness of the resulting sections in the engine as quite safe. In the near future, the pressure that is obtained in the compression sector of the motor will be measured.
The start of the engine is scheduled for the end of January.

RESUME AFTER A PAUSE

After some break active work resumed. Now (March-May 18) there are active test scrolling of a small experimental engine model. As a result, seals are being finalized - the most difficult and delicate element in rotary engines. The results are very encouraging.

Not many people know that along with classic piston engines, rotary units are used in the automotive industry, called Wankel motors by the name of the inventor. They are engines with an internal principle of fuel combustion, however, its structure and operating principles are completely different. Today we will talk about rotary motors in more detail.

Structural device of a rotary engine

The main parts of the Wankel engine in their design have nothing to do with classic internal combustion engines.

Its main parts are as follows:

1. Main working chamber

The body of any rotary unit is an oval metal chamber in which the main working processes take place - intake mode, compression stroke, fuel combustion process and exhaust gases. The shape of the camera is not accidental. It is made in such a way that when interacting with the rotor, its walls come into contact with all its vertices, forming several closed contours. The intake and exhaust ports of such motors do not have valves. They are located directly on the sides of the working chamber and are connected directly to the exhaust pipe and power system.

2. Rotor

The shape of the rotor is somewhat reminiscent of a triangle, the edges of which have a convex outward rounding. In addition, each of its sides is made with a small selection, which increases the volume of the resulting closed combustion chamber and increases the speed of the rotor. The purpose of this component is similar to the functions of pistons in a conventional internal combustion engine. The occurrence of work cycles occurs by creating the three child chambers already mentioned above. The central part of the rotor is endowed with a toothed hole connecting the rotor to the drive, fixed in turn to the output shaft. This link determines in which direction and along which trajectory the rotor will move inside the main working chamber.

3. Output shaft

The functions of the output shaft of a rotary engine are similar to those of the crankshaft of classical power units. It is endowed with semicircular protrusions-cams that have an asymmetrical alignment with a clear offset from the central working axis. Several rotors are placed on the shaft, put on their working cam. Their asymmetric arrangement creates the prerequisites for the formation of a torque that occurs as a result of the force pressure of each of the rotors.

We think you have already guessed that rotary engines have a multilayer structure, which implies the creation of several working chambers in which several rotors rotate. The only unifying link in this work is the output shaft rotating as a result of this synchronous interaction. "Layers" are securely fastened together with many bolts located along the edges. The cooling of such engines is flow-through. It implies the presence of antifreeze not only around the common block, but also in each of its parts.

In the Wankel engine, all work is built by the same combustion method. fuel mixture, as in piston engines. However, they do not provide any static combustion chambers. The pressure arising from the combustion of fuel is created in separately formed chambers, which are separated from the common working chamber by rotary faces.

The rotor itself is constantly in contact with its tops with the walls of the chamber, at each moment of time creating another closed loop. When it rotates, the contours alternately expand, then compress. During these cycles, air and fuel enter the chamber, which, as a result of the force of the rotor, is compressed and ignited, by its expansion giving the rotor another rotational impulse. Exhaust gases are ejected through the holes into the exhaust system, after which the chamber is again filled with fuel-air composition.

Advantages and disadvantages of rotary motors

The use of rotary motors has a number of undeniable advantages.

Fewer internal components. Similar to the four-cylinder piston engine, the rotary "brother" is endowed with only four main parts: a common chamber, a pair of rotors and a camshaft. A classic ICE with similar cycles of operation consists of at least forty moving parts, each of which is subject to wear.
Softness of work. During the operation of rotary units, vibrations practically do not occur, due to the fact that all moving parts rotate in only one direction. We think you know that the work of pistons in a conventional engine is multidirectional. It alternates forward movement with reverse movement.
low rhythm. Since each rotor is only responsible for rotating one third of the full circle of the output shaft, the movement required for this is noticeably slower, which greatly increases the reliability of the Wankel motor.

Negative factors in the use of rotary engines, of course, cannot be ruled out.

No rotary engine can clearly adapt to the regulations of the environmental standards of various countries.. It can in no way be called environmentally friendly due to the serious amount of carbon dioxide emissions, which are unrealistic to reduce.
The high cost of manufacturing. The production of rotary engines is very expensive, mainly due to small serial batches. Concerns produce very few of them, which does not require special cost optimization in manufacturing.
Resource limitation. The functional stock of Wankel rotary motors is very limited. It rarely exceeds 100-150 thousand kilometers, upon reaching which they require a complete overhaul ( overhaul) or replacement.
Increased fuel consumption. The main reason for the increased "voracity" is their low compression ratio. The engine, holding the required power, compensates for it due to the larger amount of fuel supplied inside the closed chambers.

Outcome

Summing up, let's say that rotary power units, of course, have the right to exist. They have a number of undeniable "pluses" that make them possible, albeit small, use in automotive production. On the other hand, the severity of the "minuses" is very noticeable. In many countries of the world, they simply cannot be applied due to existing environmental standards, and serious fuel consumption and limited working life makes the purchase of cars with rotary engines completely unprofitable. We predict that they will still be on the market for some time, but soon enough they will be replaced by hybrid power systems, the development of which is carried out at an absolutely grandiose pace.

Steam engines and internal combustion engines have one common drawback - the reciprocating movement of the piston must be converted into rotational movement of the wheels. Hence the obviously low efficiency and high wear of the mechanism elements. Many wanted to build an internal combustion engine so that all moving parts in it only rotated - as happens in electric motors.

However, the task turned out to be not easy, only a self-taught mechanic, who in his entire life never received a higher education, or even a working specialty, managed to successfully solve it.

Felix Heinrich Wankel (1902–1988) was born on August 13, 1902 in the small German town of Lahr. During the First World War, Felix's father died, because of which the future inventor had to leave the gymnasium and go to work as an apprentice seller in a bookstore at a publishing house. Through this work, Wankel became addicted to reading books, from which he independently studied technical disciplines, mechanics and automotive engineering.

There is a legend that the solution to the problem came to the seventeen-year-old Felix in a dream. Whether this is true or not is unknown. But it is obvious that Felix had a very outstanding ability to mechanics and a "non-soapy" look at things. He understood how all four cycles of a conventional internal combustion engine (injection, compression, combustion, exhaust) can be carried out while rotating.

Quite quickly, Wankel came up with the first engine design, and in 1924 he organized a small workshop, which also served as an impromptu "laboratory". Here Felix began to conduct the first serious research in the field of rotary piston internal combustion engines.

From 1921, Wankel was an active member of the NSDAP. He advocated party ideals, was the founder of the All-German Military Youth Association and the Jungführer of various organizations. In 1932, he left the party after accusing one of his former colleagues of political corruption. However, on a counter-charge, he himself had to spend six months in prison. Released from prison thanks to the intercession of Wilhelm Keppler, he continued to work on the engine. In 1934 he created the first prototype and received a patent for it. He designed new valves and combustion chambers for his motor, created several different versions of it, developed a classification of kinematic schemes for various rotary piston machines.

In 1936, BMW became interested in the Wankel engine prototype - Felix received money and his own laboratory in Lindau to develop experimental aircraft engines.

However, until the very defeat of Nazi Germany, not a single Wankel engine went into production. Perhaps it took too much time to bring the design to mind and create mass production.

After the war, the laboratory was closed, the equipment was taken to France, and Felix was left without a job (his former membership in the National Socialist Party affected him). However, Wankel soon got a position as a design engineer at NSU Motorenwerke AG, one of the oldest manufacturers of motorcycles and cars.

In 1957, by the joint efforts of Felix Wankel and NSU lead engineer Walter Froede, a rotary piston engine was first installed on the NSU Prinz car. The initial design turned out to be far from perfect: even to replace the candles, it was necessary to disassemble almost the entire “engine”, reliability left much to be desired, and it was a sin to talk about efficiency at this stage of development. As a result of the tests, a car with a traditional internal combustion engine went into the series. Nevertheless, the first rotary-piston engine DKM-54 proved its fundamental performance, opened up directions for further refinement and demonstrated the colossal potential of the “rotors”.

Thus, new type ICE finally got its start in life. In the future, it will have many more improvements and improvements. But the prospects for a rotary piston engine are so attractive that nothing could stop engineers from bringing the design to operational excellence.

Before analyzing the advantages and disadvantages of rotary piston internal combustion engines, it is still worth considering their design in more detail.
A round hole was made in the center of the rotor, covered from the inside with teeth like a gear. A rotating shaft of smaller diameter, also with teeth, is inserted into this hole, which ensures that there is no slippage between it and the rotor. The ratios of the diameters of the hole and the shaft are chosen so that the vertices of the triangle move along the same closed curve, which is called the "epitrochoid" - Wankel's art as an engineer was to first understand that this is possible, and then calculate everything exactly. As a result, the piston, which has the shape of a Reuleaux triangle, cuts off three chambers of variable volume and position in the chamber, repeating the shape of the curve found by Wankel.

The design of a rotary piston internal combustion engine allows you to implement any four-stroke cycle without the use of a special gas distribution mechanism. Thanks to this fact, the "rotor" turns out to be much simpler than a conventional four-stroke piston engine, in which, on average, there are almost a thousand more parts.

Sealing of working chambers in rotary piston engine provided by radial and end sealing plates pressed against the “cylinder” by tape springs, as well as by centrifugal forces and gas pressure.

Another of its technical features is its high “labor productivity”. For one complete revolution of the rotor (that is, for the cycle "injection, compression, ignition, exhaust"), the output shaft makes three complete revolutions. In a conventional piston engine, such results can only be achieved using a six-cylinder internal combustion engine.

After the first successful demonstration of a rotary internal combustion engine in 1957, the largest auto giants began to show increased interest in the development. At first, the license for the engine, which received the informal name "Wankel", was bought by Curtiss-Wright Corporation, a year later, Daimler-Benz, MAN, Friedrich Krupp and Mazda. In just a very short period of time, licenses for new technology acquired about a hundred companies worldwide, including such monsters as Rolls-Royce, Porsche, BMW and Ford.
Such interest in the "wankel" of such large players in the automotive market is due to its great potential and significant advantages - a rotary piston engine has 40% fewer parts, it is easier to repair and manufacture.

In addition, the Wankel is almost twice as compact and lighter as a traditional piston ICE, which in turn improves the car's handling, facilitates the optimal location of the transmission and allows for a more spacious and comfortable interior.

The rotary piston engine develops high power with a rather modest fuel consumption. For example, a modern “wankel” with a volume of only 1300 cm3 develops a power of 220 hp, and with a turbocharger - all 350. Another example is a miniature OSMG 1400 engine weighing 335 g (5 cm3 working volume) develops a power of 1.27 liters .With. In fact, this little one is 27% stronger than a horse.

Another important advantage is the low level of noise and vibration. The rotary piston engine is perfectly balanced mechanically, in addition, the mass of moving parts (and their number) in it is much less, so that the “Wankel” runs much quieter and does not vibrate.

And finally, the rotary piston engine has excellent dynamic characteristics. In low gear, you can accelerate the car to 100 km / h at high engine speeds without much load on the engine. In addition, the “Wankel” design itself, due to the lack of a mechanism for converting reciprocating motion into rotational motion, is able to withstand high speed than a traditional ICE.

After the NSU Spyder, released in 1964, followed legendary model NSU Ro 80 (there are still many clubs of owners of these cars in the world), Citroen M35 (1970), Mercedes C-111 (1969), Corvette XP (1973). But the only mass producer was Japanese Mazda, which has been producing since 1967, sometimes 2-3 new models with RPD. Rotary engines were put on boats, snowmobiles and light aircraft. The end of euphoria came in 1973, at the height of the oil crisis. It was then that the main drawback of rotary engines appeared - inefficiency. With the exception of Mazda, all automakers ended rotary programs, and the Japanese company's sales in America declined from 104,960 cars sold in 1973 to 61,192 in 1974.
Along with undeniable advantages, the Wankel also had a number of very serious drawbacks. First, durability. One of the first prototypes of rotary-piston engines ran out of service in just two hours. The next, more successful DKM-54 had already endured a hundred hours, but this was still not enough for the normal operation of the car. The main problem lay in the uneven wear of the inner surface of the working chamber. During operation, transverse furrows appeared on it, which received the speaking name "devil's marks".

IN Mazda after acquiring a license for the Wankel, a whole department was formed to improve the rotary piston engine. Pretty soon it turned out that when the triangular rotor rotates, the plugs on its tops begin to vibrate, as a result of which “devil marks” are formed.

At present, the problem of reliability and durability has been finally solved by using high-quality wear-resistant coatings, including ceramic ones.

Other serious problem- increased toxicity of the Wankel exhaust. Compared to a conventional reciprocating internal combustion engine, a “rotornik” emits less nitrogen oxides into the atmosphere, but much more hydrocarbons, due to incomplete combustion of fuel. Quite quickly, Mazda engineers, who believed in the bright future of the Wankel, found a simple and effective solution to this problem. They created the so-called thermal reactor, in which the hydrocarbon residues in the exhaust gases were simply “burned out”. The first car to implement this scheme was the Mazda R100, also called the Familia Presto Rotary, released in 1968. This car, one of the few, immediately passed the very stringent environmental requirements put forward by the United States in 1970 for imported cars.

The next problem of rotary piston engines partially follows from the previous one. This is economy. The fuel consumption of a standard "wankel" due to incomplete combustion of the mixture is significantly higher than that of a standard internal combustion engine. Once again, Mazda engineers set to work. Through a series of measures, including redesigning the thermoreactor and carburetor, adding a heat exchanger to the exhaust system, developing a catalytic converter, and introducing a new ignition system, the company has achieved a 40% reduction in fuel consumption. As a result of this undoubted success, in 1978 was released sport car Mazda RX-7.

It is worth noting that at that time only Mazda and ... AvtoVAZ produced cars with rotary piston engines all over the world.
It was in the disastrous year of 1974 that the Soviet government created a special design bureau RPD (SKB RPD) at the Volga Automobile Plant - the socialist economy is unpredictable. In Togliatti, work began on the construction of workshops for the mass production of "wankels". Since the VAZ was originally planned as a simple copyer of Western technologies (in particular, Fiat ones), the factory specialists decided to reproduce the Mazda engine, completely discarding all the ten-year developments of domestic engine-building institutes.

Soviet officials negotiated with Felix Wankel for quite some time regarding the purchase of licenses, some of which took place right in Moscow. True, no money was found, and therefore it was not possible to use some proprietary technologies. In 1976, the first Volga single-section VAZ-311 engine with a capacity of 65 hp was put into operation, it took another five years to fine-tune the design, after which an experimental batch of 50 units of VAZ-21018 rotary "units" was produced, which instantly dispersed among VAZ workers. It immediately became clear that the engine only outwardly resembled a Japanese one - it began to crumble in a very Soviet way. The management of the plant was forced to replace all engines with serial piston engines in six months, cut the staff of SKB RPD by half and suspend the construction of workshops. The salvation of the domestic rotary engine building came from the special services: they were not very interested in fuel consumption and engine life, but they were very interested in dynamic characteristics. Immediately, a two-section RPD with a power of 120 hp was made from two VAZ-311 engines, which began to be installed on the “special unit” - VAZ-21019. It is this model, which received the unofficial name "Arkan", that we owe countless tales about police "Cossacks" catching up with fancy "Mercedes", and many law enforcement officers - with orders and medals. Until the 90s, the outwardly unpretentious Arkan really easily overtook all the cars. In addition to VAZ-21019, AvtoVAZ also produces small batches of VAZ-2105, -2107, -2108, -2109, -21099 cars. The maximum speed of the rotary "eight" is about 210 km / h, and it accelerates to hundreds in just 8 seconds.

Revived on special orders, SKB RPD began to make engines for water sports and motorsport, where cars with rotary engines began to win prizes so often that sports officials were forced to ban the use of RPD.

In 1987, Boris Pospelov, head of the SKB RPD, died, and Vladimir Shnyakin, a man who came to the automotive industry from aviation and dislikes ground transport, was elected at a general meeting. The main direction of SKB RPD is the creation of engines for aviation. This was the first strategic mistake: we produce disproportionately fewer cars, and the plant lives from the sold engines.

The second mistake was the orientation in the preserved production automotive RPD for low-power VAZ-1185 engines of 42 hp for the Oka, although more voracious, but more dynamic rotary engines are asking for the fastest domestic cars- for example, on the "eight". The same Japanese install "wankels" only on sports models. As a result, there were only a few rotary minicars "Oka" on Russian roads. In 1998, a civilian version of the two-cylinder rotary 1.3-liter VAZ-415 engine was finally prepared, which was installed on the VAZ-2105, 2107, 2108 and 2109.

In May 1998, the ring VAZ-110 "RPD-sport" (190 hp, 8500 rpm, 960 kg, 240 km/h) was homologated. Alas, things did not go further than a single sample, more often shown at exhibitions than starting in races. The 110 was the most powerful in the peloton, but the frankly crude design each time did not allow it to demonstrate its full potential. However, the most offensive thing is that at VAZ they quickly cooled off towards the rotary direction, and the unique Lada was converted into a rally car with a conventional internal combustion engine.

So why haven't all the leading car manufacturers switched to Wankel yet? The fact is that the production of rotary piston engines requires, firstly, a well-honed technology with a wide variety of nuances, and not every company is ready to follow the path of the same Mazda, stepping on numerous "rakes" along the way. And secondly, we need special high-precision machines capable of turning surfaces described by such a cunning curve as an epitrochoid.

The Mazda RX-7 is one of the first cars to feature a Wankel rotary piston engine. There have been four generations in the history of the Mazda RX-7. First generation from 1978 to 1985. Second generation - from 1985 to 1991. Third generation - from 1992 to 1999. Last, fourth generation - from 1999 to 2002. The first generation RX-7 appeared in 1978. It had a mid-engine layout and was equipped with a rotary engine with a capacity of only 130 hp. With.

At present, only Mazda is engaged in serious research in the field of rotary piston engines, gradually improving their design, and most of the pitfalls in this area have already been overcome. "Wankels" are quite consistent with world standards in terms of exhaust toxicity, fuel consumption and reliability. For modern machine tools, the surfaces described by the epitrochoid are not a problem (just as much more complex curves are not a problem), new structural materials make it possible to increase the service life of a rotary piston engine, and its cost is already lower than that of a standard internal combustion engine due to fewer used details.

Like NSU, Mazda in the 60s. was a small company with limited technical and financial resources. The basis of its lineup was delivery trucks and family runabouts. Therefore, it is not surprising that the Mazda 110S Cosmo sports coupe (982 cm3, 110 hp, 185 km/h) was created for more than 6 years and turned out to be very capricious and expensive. And the damaged reputation of the NSU Ro80 did not contribute to the excitement (in 1967-1972 only 1175 "spaces" found their owners), but the world interest in the 110S contributed to an increase in sales of all the rest of the company's products!

To prove that the RPD is just as reliable (its superiority in power has already become obvious to everyone), Mazda took part in the competition for almost the first time in its life, and chose the most difficult and longest race - the 84-hour Marathon De La Route, held on Nurburgring. How the crew from Belgium managed to take 4th place (the second car retired three hours before the finish line due to jammed brakes), losing only to the Porsche 911 “grown up” on the Nordschleife, seems to remain a mystery.

Wankel workshop in Lindau

Although since then the Japanese “rotorniks” have become regulars on the race tracks, they had to wait 16 years for a major success in Europe. In 1984, the British won the prestigious Spa-Francochamps daily race with an RX-7. But in the USA, in the main market of the "seven", her racing career developed much more successfully: from the moment she made her debut in the IMSA GT championship in 1978 and until 1992, she won more than a hundred stages in her class, and from 1982 to 1992 she won more than a hundred stages. excelled in the main race of the series - 24 hours of Daytona.

In the rally, the Mazda did not go so smoothly. As was often the case with Japanese teams (Toyota, Datsun, Mitsubishi), they performed only at certain stages of the World Rally Championship (New Zealand, Great Britain, Greece, Sweden), which were primarily of interest to the marketing departments of concerns. There were enough national titles: for example, in 1975-1980. Rod Millen won as many as five in New Zealand and the USA. But in the WRC, the successes were exclusively local: the best that the RX-7 showed was 3rd and 6th places in the Greek Acropolis in 1985.

Well, the loudest success of Mazda in general and RPD in particular was the victory of its sports prototype 787B (2612 cm3, 700 hp, 607 Nm, 377 km/h) at Le Mans in 1991. Moreover, it was not only fast pilots and competitive equipment that helped to overcome the factory Porsches, Peugeot and Jaguars: the perseverance of Japanese managers also played a role, regularly “knocking out” all sorts of relaxations in the regulations for rotors. So, on the eve of the victory of the 787th, the organizers of the race agreed to compensate for the voracity of the “rotors” with a 170-kilogram (830 versus 1000) weight reduction. The paradox was that, unlike gasoline engines, the "appetite" of the RPD with further forcing grew at a much more modest pace than that of conventional piston engines, and the 787th turned out to be more economical than its main competitors!

It was a shock. Mercedes, which Stern magazine for its conservatism called nothing more than “a car manufacturer for 50-year-old gentlemen in hats,” presented a supercar in 1969 that even struck the imagination in color. The defiant bright orange color, emphatically wedge-shaped shape, mid-engine layout, gull-wing doors and a heavy-duty three-section RPD (3600 cm3, 280 hp, 260 km / h) - for a conservative Mercedes it was something!

And since the company did not build concepts, everyone believed that the C111 had only one way: a small-scale (homologation) assembly and a great racing future, because since 1966 the FIA allowed the RPD to official competitions. And checks rained down at the headquarters of Mercedes with a request to enter the right amount for the right to possess C111. The Stuttgarters, on the other hand, further fueled interest in the Eske, in 1970 introducing the second generation of the coupe with an even more fantastic design, a 4-section rotor and mind-blowing performance (4800 cm3, 350 hp, 300 km / h). To fine-tune, Mercedes built five mock-ups that spent days and nights at the Hockenheimring and Nurburgring, preparing to set a series of speed records. The press relished the upcoming "clash of the titans" between the rotary Mercedes, the naturally aspirated Ferrari and the supercharged Porsche in the World Endurance Championship. Alas, the return to big sport did not take place. Firstly, C111 was very expensive even for Mercedes, Secondly, the Germans could not put such a crude design on sale. And after the Caribbean oil crisis, they generally covered the project, focusing on diesel engines. They were equipped latest versions C111, who set several world records.

Having no completed technical education, at the end of his life, Felix Wankel achieved world recognition in the field of engine building and sealing technology, having won a lot of awards and titles. The streets and squares of German cities (Felix-Wankel-Strasse, Felix-Wankel-Ring) are named after him. In addition to engines, Wankel developed a new concept for high-speed craft and built several boats himself.

The most interesting thing is that the rotary engine, which made him a millionaire and brought him worldwide fame, Wankel did not like, considering him an "ugly duckling." Real working RPDs were made according to the so-called "KKM concept", which provides for planetary rotation of the rotor and requires the introduction of external counterweights. A significant role was played by the fact that this scheme was proposed not by Wankel, but by NSU engineer Walter Freude. Until recently, Wankel himself considered the ideal engine layout “with rotating pistons without unevenly rotating parts” (Drehkolbenmasine - DKM), conceptually much more beautiful, but technically complex, requiring, in particular, the installation of spark plugs on a rotating rotor. Nevertheless, rotary engines all over the world are associated precisely with the name of Wankel, since everyone who knew the inventor closely unanimously claims that without the irrepressible energy of the German engineer, the world would not have seen this amazing device. Felik Wankel passed away in 1988.
The history of the Mercedes 350 SL is curious. Wankel really wanted to have a rotary Mercedes C-111. But the company Mercedes did not go to meet him. Then the inventor took the serial 350 SL, threw out the “native” engine from there and installed a rotor from the C-111, which was 60 kg lighter than the previous 8-cylinder, but developed significantly more power (320 hp at 6500 rpm). In 1972, when the engineering genius finished work on his next miracle, he could have been behind the wheel of the fastest Mercedes SL-class at that time. The irony was that Wankel never got a driver's license for the rest of his life.

We owe the revival of interest in RPD to a new Mazda engine Renesis (from RE - Rotary Engine - and Genesis). Over the past decade, Japanese engineers have managed to solve all the main problems of RPD - exhaust toxicity and inefficiency. Compared to its predecessor, it was possible to reduce oil consumption by 50%, gasoline by 40% and bring the emission of harmful oxides to Euro IV standards. A two-cylinder engine with a volume of only 1.3 liters produces 250 hp. and takes up much less space in the engine compartment.

Specially for new engine the Mazda RX-8 car was developed, which, according to the brand manager Mazda Motor Europe Martin Brink, was created according to a new concept - the car was "built" around the engine. As a result, the weight distribution along the axes of the RX-8 is ideal - 50 to 50. The use of a unique shape and small dimensions of the engine made it possible to place the center of gravity very low. "RX-8 is not racing monster, but it's the best driving car I've ever driven," Martin Brink enthused Popular Mechanics.

Barrel of honey...

Without a doubt, at first glance, a rotary piston engine has a lot of advantages over traditional engines internal combustion:
- 30-40% fewer parts;
- Smaller in 2-3 times dimensions and weight, in comparison with the standard internal combustion engine corresponding in power;
- Smooth torque response over the entire rpm range;
- Absence of a crank mechanism, and, consequently, a much lower level of vibration and noise;
- High level of revolutions (up to 15000 rpm!).

A spoon of tar…

It would seem that if the Wankel has such advantages over a piston engine, then who needs these bulky, heavy, rattling and vibrating piston engines? But, as is often the case, in practice, everything is far from so chocolate. Not a single ingenious invention, having left the threshold of the laboratory, was sent to the basket marked "for waste." Serial production was found not on one stone, but on a whole placer of granite:
- Development of the combustion process in a chamber of unfavorable shape;
- Ensuring tightness of seals;
- Ensuring work without warpage of the body in conditions of uneven heating;
- Low thermal efficiency due to the fact that the RPD combustion chamber is much larger than that of a traditional internal combustion engine;
- High fuel consumption;
- High toxicity of gaseous products of combustion;
- Narrow temperature zone for RPD work: at low temperatures engine power drops sharply, at high - rapid wear rotor seals.

And what else? Pluses or minuses? Is the game worth the candle? Does it make sense (if not more - the possibility) to master the mass production of RPDs?

The main difference between the internal structure and the principle of operation of a rotary engine from an internal combustion engine is the complete absence of motor activity, while it is possible to achieve high engine speeds. The rotary engine, or otherwise the Wankel engine, has a number of other advantages, which we will consider in more detail.

The general principle of the design of a rotary engine

The RPD is clad in an oval body for optimal placement of the triangular rotor. Distinctive feature rotor in the absence of connecting rods and shafts, which greatly simplifies the design. In fact, the key parts of the RD are the rotor and stator. The main motor function in this type of motor is carried out due to the movement of the rotor located inside the housing, which is similar to an oval.

The principle of operation is based on the high-speed movement of the rotor in a circle, as a result, cavities are created to start the device.

Why are rotary engines not in demand?

The paradox of a rotary engine lies in the fact that, for all its simplicity of design, it is not as in demand as an internal combustion engine, which has very complex design features and difficulties in carrying out repair work.

Of course, the rotary engine is not without drawbacks, otherwise it would be widely used in modern automotive industry, and perhaps we would not have known about the existence of an internal combustion engine, because the rotary one was designed much earlier. So why complicate the design so much, let's try to figure it out.

Obvious shortcomings of the rotary motor can be considered the lack of reliable sealing in the combustion chamber. This is easily explained by the design features and operating conditions of the motor. In the course of intense friction of the rotor with the cylinder walls, uneven heating of the body occurs and, as a result, the metal of the body expands from heating only partially, which leads to pronounced violations of the sealing of the body.

To enhance the sealing properties, especially if there is a pronounced difference temperature conditions between the chamber and the intake or exhaust system, the cylinder itself is made of different metals and placed in different parts of the cylinder to improve tightness.

To start the motor, only two candles are used, this is due to the design features of the motor, which make it possible to produce 20% more efficiency, in comparison with an internal combustion engine, for the same period of time.

Zheltyshev rotary engine - principle of operation:

Benefits of a rotary engine

With small dimensions, it is able to develop high speed However, there is a big minus in this nuance. Despite its small size, it is the rotary engine that consumes a huge amount of fuel, but the engine's service life is only 65,000 km. So, an engine of only 1.3 liters consumes up to 20 liters. fuel per 100 km. Perhaps this was the main reason for the lack of popularity of this type of motor for mass consumption.

The price of gasoline is always considered topical issue humanity, given that the world's oil reserves are located in the Middle East, in a zone of constant military conflicts, gasoline prices remain quite high, and in the short term there are no trends to reduce them. This leads to the search for solutions for the minimum consumption of resources without sacrificing power, which is the main argument in favor of the internal combustion engine.

All this together has determined the position of rotary engines as a suitable option for sports cars. However, the world-famous car manufacturer Mazda continued the work of the inventor Wankel. Japanese engineers are always trying to get the most out of unclaimed models through modernization and use innovative technologies, which allows us to maintain a leading position in the global automotive market.

The principle of operation of the Akhriev rotary engine on the video:

The new model "Mazda", equipped with a rotary engine, is not inferior in power to the advanced German models, delivering up to 350 horsepower. At the same time, fuel consumption was incomparably high. Mazda design engineers had to reduce the power to 200 horsepower, which made it possible to normalize fuel consumption, however, the compact size of the engine made it possible to give the car additional advantages and make worthy competition European car models.

In our country, rotary engines have not taken root. There were attempts to install them on the transport of specialized services, but this project was not funded in the proper amount. Therefore, all successful developments in this direction belong to Japanese engineers from the Mazda company, which intends to show a new car model with a modernized engine in the near future.

How a Wankel rotary motor works on video

The principle of operation of a rotary engine

The RPD works by rotating the rotor, so power is transferred to the gearbox through the clutch. The transforming moment consists in the transfer of fuel energy to the wheels due to the rotation of the rotor made of alloy steel.

The mechanism of operation of a rotary piston engine:

fuel compression;
fuel injection;
oxygen enrichment;
combustion of the mixture;
release of fuel combustion products.

How a rotary engine works is shown in the video:

The rotor is attached to special device, during rotation, it forms cavities independent of each other. The first chamber is filled air-fuel mixture. Subsequently, it is thoroughly mixed.

Then the mixture passes into another chamber, where compression and ignition takes place, thanks to the presence of two candles. Subsequently, the mixture moves to the next chamber, parts of the processed fuel that exit the system are displaced from it.

This is how a complete cycle of operation of a rotary piston engine occurs, based on three cycles of work in just one revolution of the rotor. It was the Japanese developers who managed to significantly modernize the rotary engine and install three rotors in it at once, which can significantly increase power.

The principle of operation of the Zuev rotary engine:

Today, the advanced two-rotor engine is comparable to a six-cylinder internal combustion engine, and the three-rotor engine is as powerful as a 12-cylinder engine. cylinder engine internal combustion.

Do not forget about the compact size of the engine and the simplicity of the device, which allows, if necessary, to carry out repairs or complete replacement main motor units. Thus, Mazda engineers managed to give a second life to this simple and productive device.