Military Review

Rotary detonation engines - an economical perspective

19


The US Navy plans to upgrade its gas turbine power plants in the future, which are currently installed on their planes and ships, replacing conventional Brighton-powered engines with rotary-detonation engines. Due to this, it is assumed that fuel savings of about 400 million dollars annually. However, the serial use of new technologies is possible, according to experts, not earlier than in a decade.

The development of rotary or spin rotary engines in America is carried out by the Research Laboratory fleet USA. According to initial estimates, new engines will have more power, as well as about a quarter more economical than conventional engines. At the same time, the basic principles of the power plant operation will remain the same - the gases from the burnt fuel will enter the gas turbine, rotating its blades. According to the US Navy’s laboratory, even in the relatively distant future, when the entire US fleet will be powered by electricity, gas turbines will continue to be responsible for generating energy, to some extent modified.

Recall that the invention of the pulsating jet engine falls on the end of the nineteenth century. The inventor was a Swedish engineer Martin Wiberg. New power plants were widely spread during the Second World War, although they were significantly inferior in their technical characteristics to aircraft engines that existed at that time.

It should be noted that at this point in time, the American fleet numbers 129 ships using the 430 gas turbine engine. Each year, the cost of providing them with fuel amounts to about 2 billions of dollars. In the future, when modern engines will be replaced by new ones, the volume of costs for the fuel component will also change.

The internal combustion engines currently in use are based on the Brighton cycle. If you define the essence of this concept in a few words, then it all comes down to the sequential mixing of the oxidizer and fuel, the further compression of the resulting mixture, then - arson and combustion with the expansion of combustion products. This expansion is just used to drive, move the pistons, rotate the turbine, that is, perform mechanical actions, providing constant pressure. The combustion process of the fuel mixture moves at a subsonic speed — this process is called dafflagration.

As for the new engines, the scientists intend to use explosive combustion in them, that is, detonation, in which combustion occurs at supersonic speeds. And although at present the phenomenon of detonation is still not fully studied, it is known that with this type of combustion a shock wave occurs, which, propagating through a mixture of fuel and air, causes a chemical reaction, which results in the release of a fairly large amount of thermal energy. When the shock wave passes through the mixture, it is heated, which leads to detonation.

In the development of the new engine, it is planned to use certain developments that were obtained in the process of developing a detonation pulsating engine. Its principle of operation is that the precompressed fuel mixture is fed into the combustion chamber, where it is set on fire and detonated. Combustion products expand in the nozzle by performing mechanical actions. Then the whole cycle is repeated from the beginning. But the disadvantage of pulsating engines is that the repetition rate of the cycles is too low. In addition, the design of these engines themselves in the event of an increase in the number of pulsations becomes more complex. This is due to the need to synchronize the operation of valves that are responsible for the supply of the fuel mixture, as well as directly by the detonation cycles themselves. Pulsating engines are also very noisy, they need a large amount of fuel for their work, and work is possible only with constant metered injection of fuel.

If we compare detonation rotary engines with pulsating engines, then the principle of their operation is slightly different. So, in particular, in the new engines a constant continuous detonation of fuel in the combustion chamber is provided. A similar phenomenon is called spin, or rotating detonation. It was first described in 1956 by the Soviet scientist Bogdan Wojciechowski. But this phenomenon was discovered much earlier, in 1926 year. The pioneers were the British, who noticed that in certain systems there was a bright luminous "head" that moved in a spiral, instead of a detonation wave having a flat shape.

Wojciechowski, using a photographic recorder, which he himself designed, photographed the wave front, which moved in a ring combustion chamber in the fuel mixture. Spin detonation differs from flat one in that a single shock transverse wave arises in it, followed by a heated gas that has not reacted, and a zone of chemical reaction is already behind this layer. And it is precisely such a wave that prevents the burning of the camera itself, which Marlene Topchiyan called the “oblate bagel”.

It should be noted that in the past, detonation engines have already been used. In particular, we are talking about a pulsating jet engine, which was used by the Germans at the end of World War II on cruise missiles "V-1". Its production was quite simple, its use was rather easy, however, this engine was not very reliable for solving important problems.

Further, in 2008, the Rutang Long-EZ, an experimental aircraft equipped with a detonation pulsating engine, took off into the air. The flight lasted only ten seconds at a height of thirty meters. During this time, the power plant has developed thrust order 890 Newtons.

An experimental model of the engine, presented by the US Navy US laboratory, is an annular cone-shaped combustion chamber having a diameter of 14 centimeters on the fuel supply side and 16 centimeters on the nozzle side. The distance between the walls of the chamber is 1 centimeter, while the “tube” has a length of 17,7 centimeters.

A mixture of air and hydrogen is used as a fuel mixture, which is fed under the pressure of 10 atmospheres into the combustion chamber. The temperature of the mixture is 27,9 degrees. We note that this mixture was recognized as the most convenient for studying the phenomenon of spin detonation. But, according to scientists, it will be quite possible to use a fuel mixture in the new engines, consisting not only of hydrogen but also of other combustible components and air.

Experimental studies of a rotary engine have shown its greater efficiency and power compared with internal combustion engines. Another advantage is significant fuel economy. At the same time, in the course of the experiment, it was revealed that the combustion of the fuel mixture in a rotary "test" engine is not uniform, so it is necessary to optimize the design of the engine.

Combustion products that expand in the nozzle can be collected into a single gas jet using a cone (this is the so-called Coanda effect), and then this jet can be sent to the turbine. Under the influence of these gases, the turbine will rotate. Thus, the turbine operation can be partially used for propulsion of ships, and in part for the generation of energy, which is necessary for ship equipment and various systems.

The engines themselves can be produced without moving parts, which will significantly simplify their design, which, in turn, will reduce the cost of the power plant as a whole. But this is only in perspective. Before launching new engines into mass production, it is necessary to solve many difficult problems, one of which is the selection of durable heat-resistant materials.

Note that at the moment rotary detonation engines are considered one of the most promising engines. Scientists from the University of Texas at Arlington are also developing them. The power plant, which was created by them, was called the "continuous detonation engine." In the same university, studies are being conducted on the selection of various diameters of annular chambers and various fuel mixtures, which include hydrogen and air or oxygen in various proportions.

Russia is also developing in this direction. Thus, in the 2011 year, according to I. Fedorov, managing director of the Saturn research and production association, scientists of the Lyulka Scientific and Technical Center are conducting research on a pulsed air jet engine. The work is carried out in parallel with the development of a promising engine, called the "Product 129" for the T-50. In addition, Fedorov also said that the association is conducting research on the creation of promising aircraft for the next phase, which are supposed to be unmanned.

In this case, the head did not specify what kind of a pulsating engine in question. At the moment, there are three known types of such engines - valveless, valve and detonation. It is generally accepted, however, that the pulsating engines are the simplest and cheapest to manufacture.

Today, some major defense firms are conducting research into high-performance pulsating jet engines. These firms include the American Pratt & Whitney and General Electric and the French SNECMA.

Thus, it is possible to draw certain conclusions: the creation of a new promising engine has certain difficulties. The main problem at the moment lies in the theory: what exactly happens when a shock detonation wave moves in a circle is only known in general terms, and this greatly complicates the process of optimizing development. Therefore, the new technology, although it has a very large attractiveness, is not realizable on the scale of industrial production.

However, if the researchers manage to deal with theoretical issues, we can talk about a real breakthrough. After all, turbines are used not only in transport, but also in the energy sector, in which an increase in efficiency can have an even stronger effect.

Materials used:
http://science.compulenta.ru/719064/
http://lenta.ru/articles/2012/11/08/detonation/


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19 comments
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  1. Strezhevchanin
    Strezhevchanin 19 November 2012 08: 21
    0
    As I have repeatedly said, all that has already been invented for a long time and a lot of us, we can implement and modify more and more, the potential is huge, do not want to work!
    But about Rotational detonation engines, I could be wrong, but in my opinion this technology was used in the Aurora project or whatever it was.
    Yes exactly
    1. snek
      snek 19 November 2012 11: 02
      +3
      Aurora is a mythical project. There is no real evidence of its existence.
      1. Strezhevchanin
        Strezhevchanin 19 November 2012 11: 21
        -1
        I do not argue hi but there was a lot of noise, souser of the air for a total of 2 days for continuous viewing smile
      2. matvey.z
        matvey.z 20 November 2012 00: 30
        +1
        Quote: snek
        There is no real evidence of its existence.

        Except, of course, some "oddities" with the budget
        Request for $ 2,227 billion for 1987 ($ 80 million in 1086), jnrfp
        And a sharp (10 times increase in the budget for "special renovation programs", although the request was $ 139 million
    2. kostello2004
      kostello2004 3 December 2012 12: 21
      0
      there is no aurora, there is great imagination and live news
  2. tronin.maxim
    tronin.maxim 19 November 2012 08: 22
    +3
    It’s not difficult for me to say, but the Americans are great! There are interesting technologies!
    1. Strezhevchanin
      Strezhevchanin 19 November 2012 08: 29
      +1
      These technologies are a hundred years old at lunch. Everything new is well forgotten old, or recently declassified again hi
      1. iCuD
        iCuD 19 November 2012 08: 48
        +1
        Totally agree with you. As my teacher on microprocessor systems used to say: "These iPhones of yours are made using 60-70gg technologies."
        1. snek
          snek 19 November 2012 11: 08
          +2
          Quote: iCuD
          Totally agree with you. As my teacher on microprocessor systems used to say: "These iPhones of yours are made using 60-70gg technologies."

          I've always wondered what phrases like "X" were made using the technologies of the 19XXs. " Well, in the Stone Age they knew that if you hammer stones and stones, it will break - all the grinders are based on the technologies of the Stone Age. And in antiquity, they knew that if a metal is very hot, it will turn into a liquid, and if another molten metal is added to this liquid, an alloy can be obtained. It turns out that all metallurgy is based on ancient technologies. Well, this is if you use logic in the style of "iPhone on 60s technology" in any modern device, a lot of technologies and the vast majority of them appeared in the next 10-20 years.
          1. ikrut
            ikrut 19 November 2012 16: 55
            +1
            By and large - it is. Realization of ideas is always held back by effective technology. In the mid-19th century, aluminum was worth more than gold and was used exclusively in jewelry. After creating the technologies for its efficient production and processing, it became the basis of the aircraft industry. But the theory of the wing of the time was already well known and calculated.
          2. iCuD
            iCuD 20 November 2012 01: 59
            0
            Your sarcasm here is not appropriate.
            Quote: snek
            in any modern device, a bunch of technologies and the vast majority of them appeared in the next 10-20 years.

            Heh, he never liked to argue with a man who was too lazy to write a comment before writing a comment about the topic of conversation. Let's look at the main thing that has been developed over the past 20 years: touch screen - development of the late 60s and early 70s. batteries? again no. or are microprocessors really? And what do you call
            Quote: snek
            a bunch of technologies and the vast majority of them appeared in the next 10-20 years
            ??? Is it really software ??? hmm .. but this just fits your definition .. and then with a big stretch. Or do you call those things that just turned out to be a small improvement on the old?
            You don’t even have to go far for examples: you probably know why the Nobel Prize is not given immediately after any discovery, is it not?
          3. Lone gunman
            Lone gunman 9 January 2013 23: 33
            0
            physicists, mathematicians, chemists and others living with thoughts now live for 100-200 years in the future and what they are creating now in secret laboratories and in scientific research institutes - (THIS INFORMATION is verified), according to one unknown physicist, who on such fantastic projects and works, (... which our sages never dreamed of ...) for us ordinary people are simply not subject to our understanding and attitude, what THEY invent and create. civilization develops in a double way, there are "gods" and there are slaves, and everyone has their own way ... who are you ?!
  3. marmon
    marmon 19 November 2012 08: 30
    +2
    The engine is promising. But the main thing was that it may not have moving parts at all, and if so it will be very reliable. And all problems are solvable, with the modern development of supercomputers.
    1. Strezhevchanin
      Strezhevchanin 19 November 2012 08: 37
      +1
      I remember God knows in what shaggy years roofing felts were buses roofing felts trucks on gas turbines in the USSR, and now in Europe it is a promising engine!
      1) At the end of the XIX century. in the book "Self-propelled crews", published in 1898 in St. Petersburg, the Russian motorist N. Pesotsky cites the design of a gas turbine, considering it promising as a car engine. In later works on automobile engines, the most visionary authors (P. Orlovsky, N. Brilling, etc.) provide information on gas turbines and indicate their possible advantages for use as an automobile engine.
      2) CHARACTERISTICS Jaguar C-X75 CONCEPT
      Engine: Two gas turbines, 4 electric motors
      Power: 790 l / s
      Speed: 390 km / h
      Acceleration: 0 ... 100 km / h 3,4 s
      0 ... 160 km / h 5,5 s
      0 ... 300 km / h 10,3 s
  4. IlyaKuv
    IlyaKuv 19 November 2012 09: 07
    -2
    Quote: tronin.maxim
    It’s not difficult for me to say, but the Americans are great! There are interesting technologies!

    The Americans are great only in one thing: to steal other people's discoveries, patent them, and then master the skill, convince the whole world that it was they who, if you do not believe me, are looking for data on Sikorsky helicopters (a Russian emigrant), on a Rutherford bulb (the most important element in light bulb), on spaceships (like the Germans built a rocket), and much more. I am sure this development is also not theirs, but some sort of poor visiting Asian or Russian emigrant.
    1. Strezhevchanin
      Strezhevchanin 19 November 2012 09: 23
      +1
      I’ve invented and started to introduce not the same thing, I’m hoping that the implementation of our own technologies will go faster.
    2. snek
      snek 19 November 2012 11: 17
      +2
      Quote: IlyaKuv
      The Americans have done well only in one thing: steal other people's discoveries, patent them, and then mastery, convince the whole world that it was they who invented it

      Yes, in general, real arrogance: not only did they copy their miserable b-4 from our wonderful Tu-29, and their DiSi-2 from our Li-3, also some of their fraudster by the name of Christie spied on our BTs and tried to give them out for their own, only the hamburger’s mind had only the platform to copy — he didn’t finish the tower.
      The British also took no better and from our t-26 they allegedly copied their 6-ton Vickers, and then they also stole the engine from our instant-15. And they have enough arrogance to say that they say we took it from them! But we know that all these are just tales of a world government that is trying to hide the truth.
      The meanness of the Anglo-Saxons knows no bounds!
    3. Blat
      Blat 19 November 2012 13: 46
      0
      Sikorsky Pole)))))))))))))))))))))))))))) and the fact that they collect talents from all over the world are done well and, as they say, the result. here you spit saliva so it’s a fact on your face or ..................... continuation of know
      1. ikrut
        ikrut 19 November 2012 17: 00
        +1
        Sikorsky Pole by blood. But there are no aircraft building genes in the blood. And Poland was part of the Russian Empire. Sikorsky is primarily a representative and a native of the RUSSIAN Aviation School. With all the consequences. Like Zhukovsky (founder of wing theory), Mozhaisk. Zander (jet propulsion theorist) and many others. And they are Poles, Jews or Mordovians - this is the tenth thing. There are no blood Americans at all. However, some scholars are called Americans, not Irish. eg. Like the British too. It’s a pity, there are no Moldovan aircraft builders and never have been. Or am I missing something? :)))))))
        1. Blat
          Blat 19 November 2012 19: 31
          0
          that's what I noticed is typical for people like you. here if Dima Bilan is the winner of Eurovision, then he’s almost Russian, but his own brother, you know how you call them. I don’t just want to use this word here, otherwise the moderators’ adequacy and I will get a warning. So here is the Sikorsky Pole. And the comparison with the Americans is stupid. It’s not complicated, but it is the United States that is an international country, something that only people like you have been talking about for 70 years
          1. Zynaps
            Zynaps 20 November 2012 01: 29
            +1
            Quote: blat
            what only people like you have been talking about for 70 years


            because they spoke correctly. it's only the last 30 years that the USA is so multicultural. and now wrinkle your brain and remember in which year racial segregation was officially abolished in the USA? what, less than 70 years old? and Obama became their prezik only recently. and back in the 80s (I remember, because I was in the States then) there were violent discussions - to be or not to be the black president of the US baseball league.

            during WWII, national minorities became generals of the Red Army and admirals of the Navy, and in the States blacks in the fleet were barely allowed to be servants and cooks - they believed that they were not capable of more. so do not whistle, expert. especially since you don’t argue with your opponent, but you stupidly decided to distort.
            1. Blat
              Blat 21 November 2012 10: 27
              0
              so you didn’t understand that you yourself wanted to show the superiority of some people over others. and out of ignorance or deliberately calling Sikorsky Russian. but Sikorsky Pole. and since you thought that fascist I thought it was in you
  5. webdog
    webdog 19 November 2012 09: 57
    0
    The pulsating engine was invented at the end of the 1th century by the Swedish engineer Martin Wiberg. The new power plant was developed during the Second World War and was serially used on the German Vau-014 cruise missiles. These missiles were equipped with the Argus As-XNUMX engine manufactured by Argus-Werken. The power plant was inferior in characteristics to the already existing aircraft engines at that time, but was cheap and easy to manufacture.
    something like this))))))
  6. Volkhov
    Volkhov 19 November 2012 14: 46
    +1
    Judging by the photos and videos, these models are useless for anyone, the focus failed and they are looking for those who want to get into the same dead end.
    If there was an effect, then there would be large samples, and so - purely laboratory ones.
  7. I think so
    I think so 19 November 2012 18: 26
    -1
    It smacks of a dummy. If for so many years they could not even come up with a theory for this process, then it means that everything is not so simple there, even in theory. And not to mention practice. Somehow it is not visible due to which the efficiency is greater. The same amount of fuel burns, the combustion temperature is the same then the efficiency is basically the same ... If the combustion temperature is much higher, then the problems, like in the thermonuclear fusion, keep the combustion from getting to the walls, and this is an unsolvable problem ... All this is doubtful .. .
  8. Garik1971
    Garik1971 19 November 2012 22: 43
    0
    Maybe, of course, they will not make such an engine, But this will move science forward "detonatively"). They will understand the detonation process and, on its basis, create something truly revolutionary! Russian and Soviet science was also characterized by the thirst for knowledge. And what was created in Russia, you yourself know very well from a light bulb to a daukhkontorny jet engine and, say, the same wide-body aircraft. Only now we didn’t rob the world and therefore we didn’t have so many resources. But this is already a civilizational question.
  9. Garik1971
    Garik1971 19 November 2012 23: 26
    0
    I really liked the statement of Mr. Blat that "the United States is an inernational country." I was straightforwardly touched) Blessed are those who believe.
  10. gridasov
    gridasov 1 December 2012 22: 02
    0
    We have created a sufficient theoretical base on the basis of which we can speak of a decisive breakthrough in the mover of the structure. I must say right away that all analytical calculations can and should be carried out only and only on the basis of the behavior of magnetic force processes and vector-directed flows. For several years now we have been talking about the physical process and the device by which it is possible to replace the physical process organized by a screw, propeller or those turbines that are a derivative of the first. The so-called Brighton cycle is greatly simplified. No valves or control equipment. Everything is absolutely simple, but, for some reason, inaccessible to understanding. Moreover, for hyperspeed propulsors, the turbine does not have moving parts at all, but the change in energy density is fully functional. Moreover, the transformation of the substance of the medium is carried out without pre-preparation, and the use of all other fuels and oxidizing agents remains less effective.
    And the first and second video only confirms that the method of experiments without the basic theoretical basis of movement will not be forward. You can see a lot. The main thing is to understand what is happening and the consequence of what this phenomenon is and what it determines. Therefore, even if something rational is detected, it is perceived as an anomaly.

    In this case, it is worth adding that modern mathematical methods of analysis cannot describe and justify the level of data of physical processes. Therefore, we are talking about the method of high-capacity and high-performance computing, which is carried out not on the basis of binary coding of information, but based on the use of all numbers of the natural series. In this case, it is possible to simulate not only turbulent processes, but also more fleeting and complex ones in that local space which is analyzed as energetically connected. Etc.