History of the invention of steam turbines. History of the invention of turbines

- this is a heat engine, thermal energy steam in which is converted into mechanical work. Together with hydraulic turbines great value for the development of world energy, there was the invention and widespread use of steam turbines, which are the main engine of thermal power plants and nuclear power plants(NPP). The principle of operation of steam turbines is similar to hydraulic ones, the only difference is that in the first case the turbine was driven by a jet of heated steam, in the second by a jet of water. The steam turbine turned out to be simpler, more economical and more convenient than Watt's steam engine. Inventors have long tried to create a machine (steam turbine), where a jet of steam would directly rotate the impeller. At the same time, the rotation speed of the wheel must be very high due to the high speed of the steam jet.

In 1883, Laval managed to create the first steam engine, which was a light wheel with blades. Through nozzles placed at an angle, steam was directed onto the blades, which pressed on them and spun the wheel. In 1889 Laval improved the design, using a nozzle that expanded at the outlet. Due to this, the steam speed and, accordingly, the rotor rotation speed increased. The resulting jet was directed onto one row of blades, which were mounted on a disk. The steam pressure and the number of nozzles determined the power of the turbine operating on the active principle. If the exhaust steam did not enter the air, but was sent to a condenser, where it was liquefied at reduced pressure, then the turbine power would be at its highest. The Laval turbine received universal recognition; it provided great benefits when combined with high-speed machines (separators, saws, centrifugal pumps). It was also used as a drive for an electric generator, although only through a gearbox (due to its high speed).

In 1884, the English inventor Parsons patented a multi-stage jet turbine, specially created by him to drive action of an electric generator. At a lower rotation speed, the energy of the steam was used to the maximum due to the fact that the steam, passing through 15 stages, expanded gradually. Each stage had a pair of blade crowns. One crown with guide blades, which were attached to the turbine housing, was stationary. The second is movable with working blades on a disk, which was mounted on a rotating shaft. The blades of the crowns (fixed and movable) are oriented in opposite directions. This was the first steam turbine to be successfully used in industry.

In 1889, 300 turbines were already used to generate electricity; in 1899, the first power plant with Parsons turbines appeared. In 1894, the first steamship, the Turbinia, was launched, powered by a steam turbine. Soon, steam turbines began to be installed on high-speed ships. The French scientist Rato derived a comprehensive theory of turbomachines based on existing experience. Over time, the Parsons turbine gave way to compact active-reaction turbines. Although today steam turbines have largely retained the features of the Parsons turbine.

A steam turbine is the main power technological unit of an electric power plant, in which the internal energy of steam, stored during its generation, is converted into mechanical energy of rotor rotation. Unlike a steam engine, which directly converts the internal energy of steam into the work of a moving piston using the elastic forces of steam, a steam turbine, using nozzle blades, first converts the internal energy of steam into the kinetic energy of the working fluid flow, and then the latter into the mechanical energy of a rotating rotor . The term "turbine" comes from French word“turbine”, which arose from the Latin “turbo” - vortex, rotation at high speed, first used by Heron of Alexandria when describing the principle of movement of the “aeolipilus”.

The creation of a steam turbine required in-depth knowledge physical properties steam and the laws of its expiration. It was necessary to complete the formulation of the laws of thermodynamics and find new ones engineering solutions to produce work using the thermal properties of water and steam. The manufacture of the turbine became possible at a fairly high level of development of technologies for working with metals, since the required accuracy of obtaining individual parts and the strength of the elements had to be significantly higher than in the case of a steam engine.

Slovak engineer and heating scientist Aurel Stodola noted whole line advantages of a steam turbine over internal combustion engines and steam engines. These advantages include: a small number of moving parts, the absence of any contact seals and difficulties associated with ensuring their reliable operation (lubrication systems, problems associated with abrasion, etc.), a small volume of production facilities required for placement of equipment, advantages in regulation, relatively low repair costs. Today, another indisputable advantage has become obvious - a huge unit power, reaching one and a half million kilowatts today, which is simply unattainable either in internal combustion engines or in steam engines.

Aurel Stodola (1859–1942) graduated from the Budapest Polytechnic Institute in 1878, and from the Higher Technical School in Zurich in 1881. From 1892 to 1929 - Professor of the Department of Mechanical Engineering at this educational institution. His main works are devoted to automatic control, design and strength calculations of parts of steam and gas turbines. Very interesting characteristic Albert Einstein gave Stodola: “If Stodola had been born during the Renaissance, he would have been a great artist or sculptor, because the main characteristic of his personality is the power of imagination and creation. IN XIX century Such natures most often turned to technology. Here, in technology, the creative power of the age found its expression, here the passionate thirst for beauty found ways of embodiment that surpassed everything that a person not familiar with this area could offer. Stodola’s mighty impulse did not cool down during many years of teaching and passed on to the students - their eyes glow when we're talking about about the teacher. Other strong point Stodols – restless curiosity and rare clarity of scientific thinking.” The patent for the first steam turbine engine was received by the American naval engineer, Admiral Benjamin Franklin Eatherwood (1822–1915) in 1857. Following engineering developments in 1870, several such steam turbine units based on a single-stage turbine were placed on military frigates and allowed them to achieve relatively high speeds (up to 33 km/h). However, these steam turbines turned out to be too complex to manufacture and no more efficient (efficiency 6–8%) than steam engines. In 1883–1885 For the first time, primitive steam turbines were also used in sawmills in the eastern part of the United States to drive circular saws.

The creation of modern steam turbines is associated with the names of outstanding engineers of the 19th century: the Swede G. Laval and the Englishman C. Parsons.

Laval's main merit lies in the fact that he was able to create the basic elements of the turbine, bring them to perfection and combine them into a workable design, which in many respects was decades ahead of its time. If we compare the modern single-stage active turbine with its great-grandmother created by Laval (Fig. 3.2), their similarity will be striking. It turns out that over a period of more than 100 years of improvement in one of the most dynamic areas of technology, the shapes of turbine nozzles, blades, and disks have generally undergone minor changes. This is probably an unprecedented case in the history of technology. Moreover, the indicator is related to the strength of the structure.

Carl Gustav Patrick de Laval Interesting feature Laval's creativity (1845–1913) can be considered his “naked empiricism”: he created completely workable constructions, the theory of which was later developed by others. Thus, the Slovak scientist A. Stodola subsequently deeply studied the theory of the flexible shaft. He also systematized the main issues of calculating the strength of turbine disks of equal resistance. It was the lack of a good theory of steam turbines that did not allow Laval to achieve great success; moreover, he was an enthusiastic person and easily switched from one topic to another. Neglecting financial side business, this talented experimenter, not having time to implement his next invention, quickly lost interest in it, carried away by the new idea.

The English engineer Charles Algernon Parsons (1854–1931) was a different kind of person. In his multistage jet turbine (Fig. 3.3), steam expansion occurred in several stages of nozzle (stationary) and working (rotating) grids. Thanks to this, it became possible to operate the machine with significantly lower steam velocities at the exit of the nozzle grids than in the Laval turbine and with lower peripheral speeds of the working blades.

This turbine was designed to work in conjunction with an electric generator. Thus, from the very first step, Parsons correctly foresaw one of the most promising areas the use of steam turbines and in the future he did not have to look for consumers for his invention. In order to balance the axial force, steam was supplied to the middle part of the turbine shaft and then flowed to its ends. Parsons' first steam turbine had a power of only 6 hp. (about 4.4 kW) and was subjected to various tests. The main difficulties were the development of a rational design of the blades and methods of attaching them to the rotor, as well as ensuring seals. Already in the design of 1887, Parsons used labyrinth seals, which made it possible to move to turbines with unidirectional steam flow. By 1889, the number of turbines built exceeded 300 units and they were used primarily to drive electric generators. In the turbine, manufactured in 1896, the power had already reached 400 kW, and the specific steam consumption reached 9.2 kg/kW.

Energy turbine construction has developed primarily in the direction of using high-pressure steam. For the power plant in Mannheim, the Brown-Boveri plant manufactured a turbine with a power of 7000 kW at a steam pressure of 15.7 MPa and a temperature of 430 ° C. For the steam turbine built for the power plant in Langerbrugge, the steam parameters were chosen even higher: pressure 22 MPa and temperature 450 ° C.

In the USA, GE (General Electric) in Schenectady, having limited the pressure to 84 atm (8.2 MPa), began to vigorously increase the power of a single installation. At the beginning of the twentieth century, turbines with a power of 500, 1000, 2500 and 10,000 kW were developed and manufactured. Initially, these turbines were manufactured in a vertical design. However, operating experience forced the company to abandon the vertical design and switch to a horizontal turbine design. For a long time, the company produced turbines for operation in condensing mode with a power of up to 14,000 kW, and with back pressure - up to 8,000 kW.

Charles Algernon Parsons. Thanks to the work of Charles Parsons and his employees, England was ahead of the rest of the planet in the use of steam turbines: while in other countries they were just looking at steam turbines, in the United Kingdom the total power of all steam turbines built in 1896 exceeded 40,000 hp. (29420 kW). In 1899, it was decided to use two 1000 kW Parsons turbines at the Elberfeld power plant (Germany) under construction. The turbine test results, published in 1900, testified to the undeniable advantages of the units used compared to traditional “steam engines”. Soon, one of the best electrical engineering firms of that time, Brown-Boveri in Baden (Switzerland), acquired a license to produce Parsons turbines. Further, offers to purchase licenses began to grow like a snowball: in addition to the Germans, Italians and Americans (in particular, the Westinghouse company) showed interest in the turbines. Turbines began to be manufactured in Switzerland, France, and Austria-Hungary. If in 1903 the maximum turbine power was 6,500 kW, then in 1909 units with a capacity of 10,000 kW appeared, in 1915 - 20,000 kW, and in 1917 - 30,000 kW. In the company of the “founding fathers” of turbine construction, the names of the Frenchman O. Rato and the American C. Curtis appeared. But Parsons went down in the history of turbine engineering as a star of the first magnitude: in addition to purely “turbine” problems, he took upon himself (and successfully solved) the task of introducing a new engine into the fleet.

Kirillov Ivan Ivanovich (1902–1993) is one of the greatest turbine scientists, whose name is rightfully inscribed in golden letters in the history of world turbine science next to the names of L. Euler, A. Stodola and G. Flügel. He was born in 1902 in St. Petersburg in the family of a military doctor. After graduating from the Leningrad Technological Institute in 1924, Kirillov already in the thirties declared himself as a serious specialist in the field of calculations and design of steam turbines, and by the beginning of the Second World War he was an established scientist, well known among fellow turbine engineers. In 1945–1950, and then in 1961–1980. Head of the Department of Steam Turbines and Machines at the Leningrad Polytechnic Institute. In 1951–1961 organizes the Department of Turbine Engineering at the Bryansk Institute of Transport Engineering and is its head. I.I. Kirillov is the author of 25 monographs, textbooks and teaching aids, more than 350 articles in domestic and foreign journals, 80 inventions.

The second North American power engineering company, Westinghoyse, also began producing steam turbines with a unit capacity of 30, 45 and 60 thousand kW in the 20s of the twentieth century.

In the early thirties of the twentieth century, huge power steam turbine plants with a unit capacity of 160 and even 208 MW came into operation in the USA. The Europeans limited themselves to significantly lower unit power values ​​of industrial steam turbines. One of the largest was considered to be the installation in Vitkovice (Czech Republic), equipped with two turbines with a capacity of 30 and 18 MW. The rotation speed of these units was chosen to be 3000 rpm, which was determined by the AC frequency accepted in Europe (50 Hz). It should be noted that in the USA, steam turbines had a rotation speed of 1800 or 3600 rpm due to the "American" alternating current frequency of 60 Hz.

Zhiritsky Georgy Sergeevich (1893–1966) - a famous turbine scientist who not only created fundamentals engineering education in turbomachinery, but also trained numerous engineers, young scientists and teachers. In 1911 he graduated from the Kyiv First Gymnasium with a gold medal, and in 1915 he graduated from the mechanical faculty of the Kyiv Polytechnic Institute. G.S. Zhiritsky in 1918 became a teacher at the Kyiv Polytechnic Institute and combined the work of an engineer with pedagogical activity. Already in 1925, he was confirmed with the rank of professor in the course of steam engines. Zhiritsky’s monograph “Steam Engines” is coming out, having gone through five editions. In 1926, he was appointed dean of the mechanical faculty and head of the department of steam engines at the Kyiv Polytechnic Institute. In 1929, he headed the department of steam turbines at the N.E. Bauman Higher Technical School and published a two-volume textbook on steam turbines with a systematic presentation of the theory and design of steam turbines. Under his leadership in 1930–1932. The department of steam turbines was organized and the heat and power department was created at the Moscow Energy Institute. In 1947, Georgy Sergeevich created and permanently headed the department of blade machines at the Kazan Aviation Institute until 1965.

Shcheglyaev Andrey Vladimirovich (1902–1970) - a leading engineer and scientist of thermal power engineering, corresponding member of the USSR Academy of Sciences. In 1921 Shcheglyaev A.V. entered the Faculty of Mechanics at the Moscow Higher Technical University, and in 1926 he graduated from the institute and, having received the title of mechanical engineer, continued to work at the VTI, combining engineering activities with teaching at the Moscow Higher Technical University, and from 1930 at the Moscow Power Engineering Institute. Engineering and scientific activity Andrei Vladimirovich Shcheglyaev was inextricably linked with the development and improvement of new thermal power plants in the USSR, with the creation of modern powerful turbine units for supercritical steam parameters, increasing the reliability and efficiency of turbines, and with their automation. Since 1937, he has permanently headed the department of steam and gas turbines at MPEI, which under his leadership has grown into a large educational and scientific center. He created a scientific school of turbine engineers, many of whose representatives work at turbine manufacturing plants, in energy systems, in scientific institutions in Russia and abroad. A.V. Shcheglyaev is the author of more than 100 works on theory and design of turbine equipment for thermal power plants. His books “Regulation of Steam Turbines” and “Steam Turbines” (translated into Bulgarian, Chinese, Georgian, Czech, Hungarian, Japanese, spanish languages) – popular textbooks for turbine engineering students.

Shubenko-Shubin Leonid Aleksandrovich (1907–1994) - a famous engineer, teacher, thermal power scientist, academician of the National Academy of Sciences of Ukraine, founder of a scientific school on resolving issues of optimization of processes and designs of turbomachines, initiator of the creation of the Central Design and Research Bureau at the Kharkov Turbine Plant, head of the creation unique domestic turbine units. He carried out a deep theoretical study of the issues of creating powerful steam, gas and special turbines, the author of more than 200 printed scientific works. The construction was carried out by the companies Laval (Sweden), Brown-Boveri Company (Switzerland), AEG (Berlin, Germany), Bergman (Berlin, Germany), Escher-Wies (Zurich, Switzerland), Rato (France) ), Skoda (Czech Republic), Parsons (England), Metropolitan Vickers (England), later CEM and GEC-Alstom (France). Currently, well-known Japanese companies Mitsubishi, Toshiba, Hitachi, Chinese companies in Harbin and Nanjing, the German company Siemens and the French company Alstom are engaged in steam turbine construction in the world.

In the USSR, the first steam turbine was built in 1924 at the Leningrad Metal Plant (LMZ). It was designed for initial steam parameters of 1.1 MPa, 300°C and had a power of 2 MW. In 1926, a turbine with a power of 10 MW at a rotation speed of 3000 rpm was already produced, in 1930 a turbine with a power of 24 MW at a rotation speed of 3000 rpm was produced for initial steam parameters of 2.55 MPa and 375 ° C, and in 1931 g. - turbine with a power of 50 MW at a frequency of 1500 rpm for steam parameters of 2.85 MPa and 400 °C.

In 1934, the Kharkov Turbo Generator Plant (KhTGZ, and currently JSC Turboatom) came into operation in Ukraine and began producing the first Ukrainian turbines with a capacity of 50 and 100 MW at a frequency of 1500 rpm for steam parameters of 2.85 MPa and 400°C.

In 1940, the Ural Turbomotor Plant (UTMZ) was built in Sverdlovsk, which produced heating turbines with controlled steam extraction with a capacity of 12, 25, 50 MW, and later – 100 and 250 MW.

It was during this period that the production of turbines with a capacity of 50 thousand kW began - low-speed in Kharkov, high-speed in Leningrad. In 1940, LMZ and KhTGZ began manufacturing steam turbines with a capacity of 100 thousand kW. The operating experience of the low-speed KhTGZ unit at the Zuevskaya State District Power Plant turned out to be positive. Total number operating hours at the AK-100-29 turbine at Zuevskaya GRES exceeded the calculated one several times.

The great contribution to the creation and development of the theory of turbomachines, to the development and implementation of projects for stationary steam and gas turbine installations by outstanding scientists and turbine engineers I.I. Kirillova, V.V. Uvarova. (see subsection 3.6), Zhiritsky G.S., Deycha M.E., Arseneva V.G., Shcheglyaeva A.V., ShubenkoShubina L.A., Shnee Ya.I., Kosyaka Yu.F. and others. The works of foreign scientists B. Eckert, K. Bammert, W. Hawthorne, J. Horlock, W. Traupel, Wu Chung-Hua and others are well known.

Since 1946, factories began to produce high-pressure turbines with steam parameters of 8.8 MPa, 500°C with a power of 25, 50 and 100 MW at a frequency of 3000 rpm. In 1952, LMZ produced a 150 MW turbine with initial steam parameters of 16.6 MPa, 550°C with intermediate overheating to 520°C, which at that time was the most powerful single-shaft unit in Europe.

In 1958, the lead samples of the LMZ type K-200-130 and KhTGZ turbines of the K-150130 type with a power of 200 and 150 MW were produced for steam parameters of 12.8 MPa, 565°C, and in 1960 the lead samples of the LMZ and KhTGZ turbines were produced type K-300-240 with a power of 300 MW with initial supercritical steam parameters of 23.5 MPa, 560°C and intermediate superheating to 565°C. In 1965, a two-shaft turbine with a capacity of 800 MW was produced at LMZ, and a single-shaft turbine with a capacity of 500 MW was produced at KhTGZ for steam parameters of 23.5 MPa and 540°C with intermediate overheating to 540°C. Since 1969, LMZ has been producing single-shaft turbines of the K-800-240 type with a power of 800 MW for the same steam parameters.

Since 1970, the Ural Turbo Engine Plant has been producing heating turbines of the T-250-240 type with a power of 250 MW for supercritical steam parameters of 23.5 MPa, 540°C with intermediate overheating to 540°C, which have no equal in the global turbine industry.

In 1978, LMZ manufactured a unique single-shaft turbine type K-1200-240 with a power of 1200 MW at a frequency of 3000 rpm for initial steam parameters of 23.5 MPa, 540°C with intermediate overheating to 540°C, which, when the high-pressure heaters are turned off, designed to increase power to 1400 MW and is the largest single-shaft turbine in the world.

Main types of steam turbines and their parameters

The following main types of turbines are distinguished:

• depending on the number of steps – single-step (one or several speed steps) and
• multi-stage; depending on the number of buildings – single-body, double-body(TsSVD and TsND) and multi-body (TsSVD, TsVD, TsSD, TsND), single-shaft and multi-shaft;
• depending on the direction of steam flow - axial, or axial, turbines, in which steam moves along the turbine axis, iradial turbines, where steam moves perpendicular to the turbine axis;
• according to the principle of steam action - active turbines (in which the potential energy of steam is converted into kinetic energy only in fixed guide grids, and in working grids the kinetic energy of steam is converted into mechanical work) and reaction turbines (in which expansion of steam occurs in both guides and working grids each stage to approximately the same extent);
• depending on the nature of the thermal process - condensation steam turbines, in which the entire flow of fresh steam, with the exception of selections for regeneration, flowing through the flow part and expanding in it to a pressure less than atmospheric, enters the condenser, where the heat of the exhaust steam is transferred to cooling water and is not usefully used, and back pressure turbines, in which exhaust steam is sent to thermal consumers that use heat for heating or industrial purposes; condensing turbines with controlled steam extraction, in which part of the steam is taken from the intermediate stage and discharged to the heat consumer at an automatically maintained constant pressure, and the remaining amount of steam continues to work in subsequent stages and is sent to the condenser, and, finally, turbines with controlled steam extraction and back pressure, in which part of the steam is taken at constant pressure from the intermediate stage, and the rest passes through subsequent stages and is discharged to the heat consumer at a lower pressure;
• according to fresh steam parameters - medium pressure turbines (3.43 MPa, 435°C), high pressure turbines (8.8 MPa, 535°C), high pressure turbines (12.75 MPa, 565°C) and supercritical turbines (23.55 MPa, 560°C);
• for use in industry - stationary type turbines with a constant rotor speed (for operation at power plants) and a variable rotor speed (for driving pumps, compressors), as well as non-stationary type turbines with a variable rotor speed (ship and transport).

Table 3.1 Key indicators of some superheated steam turbines with a capacity of up to 200 MW

SM* – “Power machines”.

Table 3.2 Main indicators of superheated steam turbines with a capacity above 200 MW

In the designation of turbines, the first letter characterizes the type of turbine: K - condensing, T - condensing with cogeneration steam extraction, P - with production steam extraction for industrial consumers, PT - with production and heating controlled steam extraction, P - with back pressure, PR - with production selection and back pressure.

The second group (numbers) in the designation indicates the power of the turbine, MW (if it is a fraction, then the numerator is the nominal power, and the denominator is the maximum power).

The third group (numbers) in the designation indicates the initial steam pressure in front of the turbine stop valve, ata (kgf/cm2) or MPa. Below the line for turbines of types P, PT, R and PR the nominal production pressure or back pressure, ata (kgf/cm2) or MPa, is indicated. Rated power refers to the maximum power that the turbine must develop long time at nominal values ​​of all other main parameters, and maximum power is the maximum power that the turbine must develop for a long time in the absence of steam extraction for external heat consumers.

The main characteristics and parameters of modern superheated steam turbines installed at thermal power plants in Ukraine and Russia are given in Table. 3.1 and 3.2.

A turbine is a rotating device that is driven by a flow of liquid or gas.

The simplest example of a turbine is a water wheel.

Let's imagine a vertically placed wheel, on the rim of which scoops or blades are attached. A stream of water pours onto these blades from above. The wheel rotates under the influence of water. And by rotating the wheel you can activate other mechanisms. So, in a water mill the wheel rotated the millstones. And they ground flour. In hydroelectric power plants, turbines turn generators that produce electrical energy. At thermal power plants, turbine blades are driven by thermal energy, which is released when fuel is burned (gas, coal, etc.). Wind generators are driven by wind energy.

From the point of view of physics, turbines are devices that convert the energy of steam, wind, water into useful work.

Depending on what type of energy is converted in the turbines, a distinction is made between steam turbines and gas turbines.

Steam turbine

Aeolipile of Heron

In a steam turbine, the thermal energy of steam is converted into mechanical work.

Back in 130 BC, the Greek mathematician and mechanic Heron of Alexandria invented a primitive steam turbine, which was called the “aeolipil”. The device was a tightly sealed cauldron, from which two tubes were taken out. A hollow ball with two L-shaped nozzles was installed on these tubes. Water was poured into the cauldron and it was placed on fire. Steam entered the ball through tubes and escaped from the nozzles under pressure. The ball began to rotate. It was a prototype of a jet engine, in which the reactive force that rotated the ball was created by steam.

During the time of Heron, his invention was treated like a toy. It has not found any practical application.

In 1629, the Italian engineer and architect Giovanni Branchi created a steam turbine in which a wheel with blades was driven by a stream of steam.

In 1815, the English engineer Richard Treyswick installed two nozzles on the rim of a locomotive wheel and released steam through them.

From 1864 to 1884, hundreds of turbine-related inventions were patented by engineers.

And only in 1889. Swedish engineer Gustaf Laval created a steam turbine that could be used in industry. In the Laval turbine, a stream of steam emerging from the nozzles of a stationary stator pressed on the blades mounted on the wheel rim. The wheel rotated under steam pressure. Such a turbine was called active.

In the Laval turbine, the nozzle expanded at the outlet. This increased the speed of the escaping steam and, as a consequence, the rotation speed of the turbine. The Laval nozzle became the prototype of modern rocket nozzles.

A little earlier, independently of Laval, in 1884, the English engineer and industrialist Charles Algernon Parsons invented a multi-stage reactive steam turbine. Such a turbine had several rows of working blades, which were called stages. Parson patented the idea of ​​a ship that was powered by this turbine.

Gas turbine

John Barber

A gas turbine differs from a steam turbine in that it is driven not by steam from the boiler, but by the gas that is formed during the combustion of fuel. And all the basic principles of the design of steam and gas turbines are the same.

The first patent for a gas turbine was received in 1791 by the Englishman John Barber. Barber designed his turbine to propel a horseless carriage. And elements of the Barber turbine are present in modern gas turbines.

In 1903, the Norwegian Egidius Elling invented a gas turbine that produced more energy than was used to operate it. The principle of its operation was used by the English design engineer Sir Frank Whittle, who in 1930 patented a gas turbine for jet propulsion.

Tesla Turbine

Tesla Turbine

In 1913, engineer, physicist and inventor Nikola Tesla patented a turbine, the design of which was fundamentally different from that of a traditional turbine. The Tesla turbine did not have blades that were driven by steam or gas energy.

The rotating part of the turbine, the rotor, was a set of thin metal disks mounted on a shaft and separated by washers. The flow of gas or working fluid came from the outer edge of the disks and passed to the center along the gaps, twisting. It is known that if a flow of liquid or gas is directed along a flat surface, the flow begins to drag this surface along with it. The disks in Pascal's turbine were carried away by the gas flow, causing rotation.

Nikolay Alexandrov

It was not for nothing that the nineteenth century was called the age of steam. With the invention of the steam engine, a real revolution took place in industry, energy, and transport. It became possible to mechanize work that previously required too many human hands. Railways dramatically expanded the possibilities of transporting goods by land. Huge ships took to the sea, capable of moving against the wind and guaranteeing the timely delivery of goods. Expansion of volumes industrial production set the energy industry the task of increasing engine power in every possible way. However, initially it was not at all high power brought to life a steam turbine...

The hydraulic turbine as a device for converting the potential energy of water into the kinetic energy of a rotating shaft has been known since ancient times. The steam turbine has an equally long history, with one of the first designs known as Heron's turbine and dating back to the first century BC. However, let us immediately note that until the 19th century, turbines driven by steam were more likely technical curiosities, toys, than real industrially applicable devices.

And only with the beginning of the industrial revolution in Europe, after the widespread practical introduction of D. Watt’s steam engine, inventors began to take a closer look at the steam turbine, so to speak, “closely.” The creation of a steam turbine required a deep knowledge of the physical properties of steam and the laws of its flow. Its manufacture became possible only with a sufficiently high level of technology for working with metals, since the required precision in the manufacture of individual parts and the strength of the elements were significantly higher than in the case of a steam engine.

Unlike a steam engine, which performs work by using the potential energy of steam and, in particular, its elasticity, a steam turbine uses the kinetic energy of a steam jet, converting it into rotational energy of the shaft. The most important feature water vapor is the high speed of its flow from one medium to another, even with a relatively small pressure difference. Thus, at a pressure of 5 kgf/m2, the steam jet flowing from the vessel into the atmosphere has a speed of about 450 m/s. In the 50s of the last century, it was found that in order to effectively use the kinetic energy of steam, the peripheral speed of the turbine blades at the periphery must be at least half the speed of the blowing jet; therefore, with a turbine blade radius of 1 m, it is necessary to maintain a rotation speed of about 4300 rpm . Technique first half of the 19th century For centuries I have not known bearings capable of withstanding such speeds for a long time. Based on his own practical experience, D. Watt considered such high speeds of movement of machine elements unattainable in principle, and in response to a warning about the threat that a turbine could create for the steam engine he invented, he answered: “What kind of competition can we talk about if without "With the help of God, the working parts cannot be made to move at a speed of 1000 feet per second?"

However, time passed, technology improved, and the hour for the practical use of the steam turbine struck. Primitive steam turbines were first used in sawmills in the eastern United States in 1883-1885. for driving circular saws. Steam was supplied through the axis and then, expanding, was directed through pipes in the radial direction. Each of the pipes ended with a curved tip. Thus, in design, the described device was very close to the Heron turbine, had extremely low efficiency, but was more suitable for driving high-speed saws than a steam engine with its reciprocating piston movement. In addition, to heat the steam, according to the concepts of that time, waste fuel was used - sawmill waste.

However, these first American steam turbines were not widely used. Their influence on further history There is practically no technology. What can't be said about the Swede's inventions? French origin de Laval, whose name is known to any engine specialist today.

Carl Gustav Patrick de Laval

De Laval's ancestors were Huguenots who were forced to emigrate to Sweden in late XVI centuries due to persecution in their homeland. Carl Gustav Patrick (the “main” name was still considered Gustav) was born in 1845 and received excellent education, having graduated from the Institute of Technology and University in Uppsala. In 1872, de Laval began working as a chemical and metallurgical engineer, but soon became interested in the problem of creating an effective milk separator. In 1878 he managed to develop good option separator designs, which have become widespread; Gustav used the proceeds to expand work on a steam turbine. It was the separator that gave the impetus to start working on the new device, since it needed a mechanical drive capable of providing a rotation speed of at least 6000 rpm.

In order to avoid the use of any kind of multipliers, de Laval proposed placing the separator drum on the same shaft with a simple jet-type turbine. In 1883, an English patent was taken out for this design. De Laval then moved on to develop a single-stage active-type turbine, and already in 1889 he received a patent for an expanding nozzle (and today the term “Laval nozzle” is in common use), which makes it possible to reduce the steam pressure and increase its speed to supersonic. Soon after this, Gustav was able to overcome other problems that arose in the production of a functional active turbine. So, he proposed using a flexible shaft and a disk of equal resistance and developed a method for securing the blades in the disk.

On international exhibition in Chicago, held in 1893, a small de Laval turbine with a power of 5 hp was introduced. with a rotation speed of 30,000 rpm! The enormous rotation speed was an important technical achievement, but at the same time it became the Achilles heel of such a turbine, since for practical application it involved the inclusion of a reduction gearbox in the power plant. At that time, gearboxes were manufactured mainly as single-stage gearboxes, so the diameter of a large gear was often several times greater than the size of the turbine itself. The need to use bulky gear reduction gears prevented the widespread adoption of de Laval turbines. The largest single-stage turbine with a power of 500 hp. had a steam consumption of 6...7 kg/hp h.

An interesting feature of Laval’s work can be considered his “bare empiricism”: he created completely workable designs, the theory of which was later developed by others. Thus, the theory of a flexible shaft was subsequently deeply studied by the Czech scientist A. Stodola, who also systematized the main issues of calculating the strength of turbine disks of equal resistance. It was the lack of a good theory that did not allow de Laval to achieve great success; moreover, he was an enthusiastic person and easily switched from one topic to another. Neglecting the financial side of the matter, this talented experimenter, not having time to implement his next invention, quickly lost interest in it, being carried away by the new idea. A different kind of person was the Englishman Charles Parsons, son of Lord Ross.

Charles Algernon Parsons

Charles Parsons was born in 1854 and received a classical English education, graduating from Cambridge University. He chose mechanical engineering as his occupation and since 1976 began working at the Armstrong plant in Newcastle. The designer's talent and ingenuity, combined with the financial capabilities of his parents, allowed Parsons to quickly become the head of his own business. Already in 1883, he was a co-owner of the company Clark, Chapman, Parsons and Co., and in 1889 he became the owner of his own turbine and dynamism plant in Guiton.

Parsons built the first multi-stage jet-type steam turbine in 1884. It was not intended to drive relatively low-power separators, but to work in conjunction with an electric generator. Thus, from the very first step, Parsons correctly foresaw one of the most promising areas of application of steam turbines, and in the future he did not have to look for consumers for his invention. In order to balance the axial force, steam was supplied to the middle of the turbine shaft and then flowed to its ends. Parsons' first steam turbine had a power of only 6 hp. and was subjected to various tests. The main difficulties were the development of a rational design of the blades and methods of attaching them to the disk, as well as ensuring seals. Already in a design dating back to 1887, Parsons used labyrinth seals, which made it possible to move to turbines with unidirectional steam flow. By 1889, the number of turbines built exceeded 300 units; their power had not yet reached 100 hp. at a rotation speed of about 5000 rpm. Such turbines were used primarily to drive electric generators.

The relationship between the partners at Clark, Chapman, Parsons and Co. turned out to be far from rosy, and Parsons was forced to leave, leaving former colleagues and part of the copyrights formally owned by the company. In this regard, he abandoned the creation of active turbines (protected by a patent) for a long time and moved on to the development of radial multistage turbines. By improving this type, the designer was able to achieve impressive results. Thus, he reduced the specific steam consumption from 44 to 12.7 kg/kWh, but at the same time realized that the previous axial type of turbine was still more promising. Beginning in 1894, having restored the rights to the patent, Parsons again began to work on just such turbines.

At his plant he tried a variety of materials for turbine blades, but settled on bronze for saturated and moderately superheated steam, pure copper for the high pressure part, and nickel bronze for highly superheated steam. In addition, in-depth research was carried out to create a rational design for the steam supply regulator. To improve accuracy, Parsons used the intermittent relay principle to reduce friction. At the same time, other improvements were introduced, which together led to a decrease in the specific steam consumption to 9.2 kg/kWh for a 400 kW turbine manufactured in 1896.

W. Garrett Scaife

W. Garrett Scaife, Trinity College, Dublin

Towards the end of the last century, the industrial revolution reached a turning point in its development. A century and a half earlier, steam engines had significantly improved - they could run on any type of fuel and drive a wide variety of mechanisms. A technical achievement such as the invention of the dynamo, which made it possible to generate electricity in large quantities, had a great influence on the improvement of the design of steam engines. As human energy needs grew, so did the size of steam engines, until their dimensions were constrained by limitations on mechanical strength. For further development of industry it was necessary new way obtaining mechanical energy.

This method appeared in 1884, when the Englishman Charles Algernon Parsons (1854-1931) invented the first turbogenerator suitable for industrial use. Ten years later, Parsons began studying the possibility of using his invention for vehicles. Several years of hard work were crowned with success: the steamer Turbinia, equipped with a turbine, reached a speed of 35 knots - more than any ship in the Royal Navy. Compared to piston steam engines that use reciprocating piston motion, turbines are more compact and simpler in design. Therefore, over time, when power and efficiency. turbines have been significantly increased

They replaced the engines of previous designs. Currently, all over the world, steam turbines are used in thermal power plants as generator drives. electric current. As for the use of steam turbines as engines for passenger ships, their undivided dominance came to an end in the first half of this century, when diesel engines became widespread. The modern steam turbine has inherited many of the features of the first machine invented by Parsons.

Reactive and active principles underlying the operation of a steam turbine. The first of them was used in the "aeolipil" device ( A), invented by Heron of Alexandria: the sphere in which the steam is located rotates due to the action of reaction forces that arise when steam exits hollow tubes. In the second case ( b) the jet of steam directed at the blades is deflected and due to this the wheel rotates. Turbine blades ( With) also deflect the steam jet; in addition, passing between the blades, the steam expands and accelerates, and the resulting reaction forces push the blades.

The operation of a steam turbine is based on two principles of creating a circumferential force on the rotor, known since ancient times - reactive and active. As early as 130 BC. Heron of Alexandria invented a device called the aeolipile. It was a hollow sphere filled with steam with two L-shaped nozzles located on opposite sides and directed in different directions. Steam flowed out of the nozzles at high speed, and due to the resulting reaction forces, the sphere began to rotate.

The second principle is based on the conversion of potential energy of steam into kinetic energy, which does useful work. It can be illustrated by the example of Giovanni Branca's machine, built in 1629. In this machine, a jet of steam drove a wheel with blades, reminiscent of a water mill wheel.

The steam turbine uses both of these principles. A jet of high-pressure steam is directed onto curved blades (similar to fan blades) mounted on a disk. When flowing around the blades, the jet is deflected, and the disk with the blades begins to rotate. Between the blades, the steam expands and accelerates its movement: as a result, the steam pressure energy is converted into kinetic energy.

The first turbines, like Branca's machine, could not develop sufficient power because steam boilers were not capable of creating high pressure. The first operating steam engines of Thomas Savery, Thomas Newcomen and others did not require high pressure steam. Low pressure steam displaced the air under the piston and condensed, creating a vacuum. The piston lowered under the influence of atmospheric pressure, producing useful work. Experience in the construction and use of steam boilers for these so-called atmospheric engines gradually led engineers to design boilers capable of generating and withstanding pressures far in excess of atmospheric pressure.

With the advent of the opportunity to produce high-pressure steam, inventors again turned to the turbine. Various design options have been tried. In 1815, engineer Richard Trevithick tried to install two nozzles on the wheel rim of a steam locomotive engine and pass steam from the boiler through them. Trevithick's idea failed. A sawmill built in 1837 by William Avery in Syracuse (New York) was based on a similar principle. In England alone, in the 100 years from 1784 to 1884, 200 inventions related to turbines were patented, and more than half of these inventions were registered in the twenty-year period from 1864 to 1884.

None of these attempts resulted in the creation of an industrially suitable machine. These failures were partly due to ignorance of the physical laws governing the expansion of steam. The density of steam is much less than the density of water, and its “elasticity” is much greater, so the speed of the steam jet in steam turbines is much greater than the speed of water in the water turbines with which the inventors had to deal. It was found that the efficiency the turbine becomes maximum when the speed of the blades is approximately equal to half the speed of the steam; Therefore, the first turbines had very high rotation speeds.

Big number speed was the cause of a number of undesirable effects, among which not the least role was played by the danger of destruction of rotating parts under the influence of centrifugal forces. The rotation speed of the turbine could be reduced by increasing the diameter of the disk on which the blades were mounted. However, this was impossible. The steam flow in early devices could not be large, which means that the cross-section of the outlet opening could not be large. Due to this reason, the first experimental turbines had a small diameter and short blades.

Another problem related to the properties of steam caused even more difficulties. The speed of steam passing through the nozzle varies proportionally to the ratio of the inlet pressure to the outlet pressure. The maximum velocity in a convergent nozzle is achieved, however, at a pressure ratio of approximately two; a further increase in the pressure drop no longer affects the increase in jet speed. Thus, designers could not take full advantage of the power of high-pressure steam: there was a limit to the amount of energy stored in high-pressure steam that could be converted into kinetic energy and transferred to the blades. In 1889, the Swedish engineer Carl Gustav de Laval used a nozzle that expanded at the outlet. Such a nozzle made it possible to obtain much higher steam velocities, and as a result, the rotor speed in the Laval turbine increased significantly.

Parsons created a fundamentally new turbine design. It was distinguished by a lower rotation speed, and at the same time it made maximum use of steam energy. This was achieved due to the fact that in the Parsons turbine the steam expanded gradually as it passed through 15 stages, each of which was a pair of blade rims: one fixed (with guide blades attached to the turbine body), the other movable (with working blades). on a disk mounted on a rotating shaft). The blades of the fixed and movable rims were oriented in opposite directions, i.e. so that if both crowns were movable, then the steam would make them rotate in different directions.

The turbine blade rims were copper rings with blades fixed in slots at an angle of 45°. The movable rims were fixed on the shaft, the fixed ones consisted of two halves rigidly connected to the body (the upper half of the body was removed).

Alternating movable and fixed rims of blades ( A) set the direction of steam movement. Passing between the fixed blades, the steam expanded, accelerated and was directed to the movable blades. Here the steam also expanded, creating a force that pushed the blades. The direction of steam movement is shown on one of the 15 pairs of crowns ( b).

The steam directed to the stationary blades expanded in the interblade channels, its speed increased, and it was deflected so that it fell on the movable blades and forced them to rotate. In the interblade channels of the movable blades, the steam also expanded, an accelerated jet was created at the outlet, and the resulting reactive force pushed the blades.

With many movable and stationary blade rims, high rotation speeds have become unnecessary. At each of the 30 rims of the multi-stage Parsons turbine, the steam expanded slightly, losing some of its kinetic energy. At each stage (pair of crowns) the pressure dropped by only 10%, and maximum speed As a result, the steam turned out to be equal to 1/5 of the jet speed in a turbine with one stage. Parsons believed that with such small pressure drops, steam could be considered a low-compressibility liquid similar to water. This assumption gave him the opportunity to high degree accurately make calculations of steam speed, efficiency. turbines and blade shapes. The idea of ​​stepwise expansion of steam, which underlies the design of modern turbines, was only one of many original ideas embodied by Parsons.