Mode of incineration of hydrocarbon fuel and an arrangement for realization of this mode

Abstract

FIELD: mode of incineration of hydrocarbon fuel and an arrangement for its realization refers to engines and power engineering with working processes including preliminary processing of fuel.

Description

The invention relates to energy, in particular to the burning of hydrocarbon fuels, and can be used in the production of electricity, in the organization of the working process in automobile engines, jet, turbojet and turbofan aircraft and rocket engines, gas turbine and other power plants.

Various methods are known for burning hydrocarbon fuels based on the propagation of a flame front. As the main ones, one can specify periodic combustion of the fuel-air mixture in gasoline and diesel internal combustion engines [1], continuous combustion of the fuel-air (-oxidative) mixture in rocket and aircraft engines, pulsating combustion modes of the fuel-air (-oxidative) mixture in rocket and aircraft engines, continuous combustion of the air-fuel mixture in various versions of aircraft turbojets, turboprops and turbofan engines, continuous combustion of the air-fuel mixtures in gas turbine engines and power plants, as well as in other variants of burning a jet of fuel in an oxidizing medium, or a jet of a pre-mixed fuel-air (-oxidizing) mixture.

Known methods of forming a flame front by igniting a fuel-air mixture using special devices. As such devices for periodic ignition of fuel, for example, in internal combustion engines, various types of electric discharges in a gas are most often used, including a pulsed discharge between electrodes in a gas [1], a combined pulsed discharge through a gas gap and over a dielectric surface [2], a sliding discharge over the surface of the dielectric [3]. For continuous combustion of fuel, various heated elements, burners and torches with an open flame are used, etc.

It is known that, in hydrocarbon flames, gas ionization occurs at all stages of combustion, for example, in the reaction CH + O → CHO + + e - [4].

It is also known to use an electric field to intensify combustion of a fuel-air mixture in automotive internal combustion engines [5].

Methods are also known for exciting a high-pressure gas medium (tens of atmospheres) using a non-self-sustained discharge in order to create an inverse population of levels in high-power CO 2 lasers and some other gases. This is the so-called electroionization method for pumping compressed gas lasers [6]. The essence of the pumping method is the direct excitation of molecular gases by electron impact when free electrons move through a gas in an electric field. Free electrons are formed in the process of preionization of a gaseous medium, which is carried out by various methods. An electric field that accelerates free electrons is created in a gas volume using a system of electrodes placed in a gas medium. The selection of the parameters of the gaseous medium and the electric field makes it possible to carry out various types of gas excitation with high efficiency, including excitation of vibrational degrees of freedom, electronic degrees of freedom, and gas ionization.

It is also known to use a non-self-sustaining microwave discharge in a gas as a means of creating highly nonequilibrium vibrationally excited states of a molecular gas laser medium [7].

It is known to use electron beams for preionization of high pressure gas in electroionization lasers [8].

It is also known to use a sliding discharge over the surface of a dielectric in systems of preionization of electroionization lasers to obtain independent and non-independent volume discharges in interelectrode gaps [9]. In this case, the ionization of the gas medium is carried out by a stream of hard electromagnetic radiation, the source of which is a plasma of a sliding discharge. It is known that an increase in the growth rate of the potential difference U upon excitation of the creeping discharge dU / dt to values of ~ 10 13 V / s shifts the short-wavelength boundary of the creeping discharge radiation spectrum to the soft X-ray region [10]. Various types of electrode systems are known for using a sliding discharge over the surface of a dielectric as a source of preliminary ionization of a gaseous medium of a CO 2 laser, including devices with so-called plasma electrodes [11]. In these electrode systems, the main discharge current closes through a creeping discharge plasma, which led to the use of the term "plasma electrodes".

The occurrence of runaway electrons, which appear during electric breakdown of strongly overstressed gas spaces, is also known [12]. These electrons are formed as a result of pre-acceleration in the edge field region at the avalanche front of a developing gas discharge and are characterized by the fact that they are accelerated by an electric field throughout the interelectrode gap, gaining tens of kiloelectron-volts of energy. The criterion for runaway electrons is the condition:

where E f (x, φ) is the resulting electric field strength at the point "x" taking into account the main field E 0 and the polarization field of the plasma cloud E p , if the angle φ between the vectors E 0 and E p ; L 1 (w) is the energy loss of an electron with energy w per unit path length, P is the gas pressure.

An analysis of the expression for the runaway criterion of electrons (1) shows that it is possible to satisfy the runaway criterion if the electron in any way gains an energy w e higher than w 2 (Fig. 5). This can happen both at the stage of single avalanches, if the parameter E 0 / P is large enough, and later, after an avalanche-streamer transition or during the evolution of streamers, if E 0 / P «(E / P) cr . In strongly overstressed spaces, an avalanche-streamer transition occurs along the path z ~ 100 μm. As a result of such a transition, a plasma cloud is formed with a conductivity sufficient to create ionization fronts and runaway electron generation. Being in a strong electric field, the cloud is polarized. Further, the ionization process develops due to electrons escaping from the cloud and accelerating in the space charge zone. Some of these electrons acquire energy greater than w 2 and gain the ability to continuously accelerate up to the anode. To realize this situation at a gas pressure of ~ several tens of atmospheres, fields with an intensity of more than 10 6 V / cm are required.

Known methods for producing free electrons, which consist in using the phenomenon of an external photoelectric effect from metals and other materials under the influence of a flux of electromagnetic radiation [13]. The quantum yield of photoemission, that is, the number of photoelectrons emitted during the absorption of one photon, from pure metal surfaces in the visible region of the spectrum is of the order of 10 -4 electron / photon, and for hν≤10 eV, where hν is the quantum energy of electromagnetic radiation, does not exceed 10 -2 electron / photon. Metals have a high quantum yield of photoemission of ~ 10 -1 electron / photon only in the region hν> 12 eV and usually in the presence of oxide films on their surface.

There are also known methods of burning a fuel-air mixture without spreading a flame front [14, 15]. With such methods of burning fuel, conditions are created for self-ignition of the fuel-air mixture and its combustion until the stage of formation of the final oxidation products synchronously in the entire volume of the combustion chamber.

It is known that, despite the variety of methods for burning hydrocarbon fuel with a flame front and without spreading the flame front, all of them have a common characteristic feature due to the kinetics of oxidation of hydrocarbon fuel. This feature is related to the fact that the chemical reaction of hydrocarbon oxidation is a “chain reaction with degenerate branching” [16]. Moreover, the stages of chain branching are most important in combustion processes, and especially in the processes of fuel ignition. The sequence of elementary reactions of a “chain reaction with a degenerate branching” contains the initial chain nucleation reactions and the main chain — chain extension reactions, at each stage of which an active radical is formed instead of the “spent” radical. In the process of a chain oxidation reaction, a sequential degradation of the initial hydrocarbon molecules occurs with the formation of increasingly "shorter" molecules. At a certain stage in the development of the process of destructive oxidation of the initial hydrocarbons, the formation of metastable molecules of intermediate products of incomplete oxidation occurs. These products, due to the relative stability of their molecules, accumulate in the reaction medium. However, they are still not truly stable, and under the influence of external conditions they are likely to decompose, generating two active radicals that branch and nucleate new chains of the oxidation reaction of hydrocarbon molecules. Thus, a distinctive feature of the kinetics of oxidation of hydrocarbon molecules is the generation and accumulation of metastable molecules of intermediate products of incomplete oxidation, and the formation of new chains and acceleration of the oxidation reaction occurs only after a certain “preparatory” period in the decay of the accumulated metastable molecules. Upon reaching a certain decay rate of the accumulated metastable products, the reaction goes into an explosion, which corresponds to ignition of the fuel-air mixture.

In all but the examples presented above [15] of using hydrocarbon combustion to obtain thermal energy, the destruction of metastable molecules of intermediate products of incomplete oxidation of hydrocarbons occurs due to an increase in the temperature T of the gas medium due to an increase in the energy of the translational degrees of freedom in the molecules of the gas medium. In the course of increasing temperature, an increasing proportion of molecules has an energy of thermal motion exceeding the activation energy of the decay of metastable molecules of intermediate products. In collisions of metastable molecules with other molecules due to thermal motion, they can receive additional energy sufficient to activate the process of molecular decomposition. When the average energy (temperature) of the gaseous medium reaches a certain value, the rate of decomposition of metastable molecules and the formation of new chains of the hydrocarbon oxidation reaction becomes sufficient for the irreversible development of a “thermal explosion”.

In [17–21] and others related to detailed studies of the kinetics of the chemical reaction of hydrocarbon oxidation carried out in the last 15–20 years, it was shown that the key reaction leading to chain branching and irreversible transition to ignition is the decomposition of hydrogen peroxide:

where M is another molecule of the gaseous medium or the wall of the reactor.

Thus, a sensitivity analysis and an analysis of reaction pathways performed in [21] show that after the initiation reaction - hydrocarbon radical) followed by the reaction and reaction (2) performing chain branching. Next, the radicals formed in reaction (2) can form radicals for example in reactions: generating a large number of "precursors" of subsequent branching of the chain and ensuring the development of a thermal "explosion". Such chain branching is possible in the temperature range T: 900 K <T <1100 K. For higher temperatures T> 1100 K, the chain branching mechanism becomes quite simple

and relatively independent of the nature of the fuel.

Reaction (2) is described by a first order kinetic equation. In order for monomolecular decomposition to take place, the molecule must have a supply of energy, which can appear as a result of activating and deactivating collisions between molecules. The reaction rate depends on the temperature and pressure of the gaseous medium.

At the initial stages of the development of the self-ignition process, in the so-called low-temperature region, other metastable molecules of intermediate products of incomplete oxidation of hydrocarbons, such as alkyl peroxides and alkyl hydroperoxides, can also be accumulated, which, through a chain of chemical reactions, radical decays, and isomerization processes, turn into a relatively stable ketohydroperoxide group. The decomposition temperature of ketohydroperoxides is about 800 K, which is somewhat lower than that of H 2 O 2 molecules [18]. The decomposition of ketohydroperoxides leads to the formation of two active particles and the branching of the hydrocarbon oxidation reaction. However, this chain branching mechanism is degenerate, in accordance with which, immediately after its beginning, due to a slight increase in temperature, the equilibrium of reactions generating complex compounds, which are “precursors” of branching, shifts, and the branching reaction stops feeding. After this, there is a delay in the development of self-ignition (multi-stage self-ignition) until conditions are reached (temperature increase, the accumulation of a high concentration of peroxides) for the dominant chain branching process characteristic of real systems due to the decomposition of H 2 O 2 molecules [20] . This is true and is the main feature of the kinetics of hydrocarbon ignition processes for laboratory RCM experiments, the knock phenomenon in spark ignition engines, ignition in diesel engines and when controlling the ignition process in HCCI engines. In each of these systems, Н 2 О 2 is formed at low temperatures and remains relatively inert until the temperature, increasing from compression and exothermic reactions, reaches the level when Н 2 О 2 molecules rapidly fall apart through reaction (2) and do not “start” chain branching of the oxidation reaction [18].

The rate of change in the number of hydrogen peroxide molecules H 2 O 2 due to decay can be represented as:

where [M] is the molar concentration of peroxide;

k 1 - = 1.2-10 17 * exp (-45500 / RT) is the reaction rate constant (2).

From formula (4), we can obtain the expression for the "decay time constant" τ of peroxide molecules:

As an example, we estimate the decay time for the concentration of peroxide molecules [M] ~ 10 –4 mol / cm 3 obtained in [20] after compression of the fuel – air mixture in an RCM experiment. Calculations of τ (according to formula (5) give values: τ 900 = 7.8 · 10 -3 sec for Т = 900 K; τ 1000 = 6.4 · 10 -4 sec for Т = 1000 K; τ 1100 = 8 · 10 -5 sec for T = 1100 K.

The development of the hydrocarbon ignition process according to the above scheme with thermal stimulation of the decomposition of metastable molecules of intermediate products is characterized by poor controllability due to the statistical nature of the process of thermal destruction and the absence of a natural “mechanism” of rapid exposure to the temperature of the entire gas volume. When a fuel-air mixture is burned by spreading a flame front, the ignition of new portions of fuel occurs according to the same "mechanism" as the "mechanism" of a radical-thermal explosion considered above, but with some features caused by diffusion of active radicals from the flame zone and heat transfer processes.

From formula (5) it is also seen that the ignition process is sensitive to the concentration [M] of hydrogen peroxide molecules accumulated at this point. In turn, the value [M] is determined by many parameters, such as, for example, the previous "thermal history", that is, the dynamics of changes in the thermal characteristics of the effect on the fuel-air mixture; the composition of the fuel-air mixture; molecular composition of fuel, etc., directly affecting the rate of formation of hydrogen peroxide molecules. It is clear from this that, due to the large number of critical parameters, it is difficult to ensure sufficient controllability, accuracy, and repeatability of the moment of transition to the explosion. This feature is crucial for applications associated with the periodic combustion of the air-fuel mixture under changing conditions, for example, in internal combustion engines and is the main technical problem that hinders the practical implementation of some promising technologies, such as "Homogeneous Charge Compression Ignition" and "Controlled Auto Ignition "(CAI (HCCI Engine) [14].

In addition, the main consequence of the presented mechanism of ignition of the air-fuel mixture and its combustion by propagation of the flame front in internal combustion engines with spark ignition is the restriction on an unreasonably low level of acceptable compression ratio r (r≤11 ÷ 12) due to knocking (detonation ), incomplete combustion of fuel, increased toxicity of combustion products and, as a result, low efficiency.

Another unpleasant feature of the reaction with the thermal “mechanism” for stimulating branching of the chains is the relatively low rate of development of the irreversible process of self-ignition. Moreover, the rate of development of the process is underestimated not because of “fundamental natural restrictions,” but only because at the initial stage of the irreversible transition to a thermal explosion, the temperature rises relatively slowly and, consequently, the number of decaying metastable molecules from the number accumulated in the fuel air mixture. It is this circumstance that also limits the speed of flame propagation, or, which is equivalent for most applications with a continuous mode of fuel combustion, the feed rate of the fuel-air mixture into the combustion zone.

When continuously burning fuel, for example, in ramjet aircraft or gas turbine engines, various methods of gas-dynamic flame stabilization are used to organize combustion in a high-speed stream. One of them is the placement of a poorly streamlined body (stabilizer), which creates a redistribution of pressure in the flow and, as a result, a zone of reverse currents. In this stabilization method, the combustion products circulating in the reverse current zone serve as a constant source of ignition for the newly incoming air-fuel mixture. The stability of the turbulent diffusion flame on the stabilizer with respect to the speed of the incoming flow and fuel consumption is a very critical parameter, which largely determines the characteristics of the power plant. The flame is stable in those cases when the feed rate of the fuel-air mixture does not exceed a value at which reverse currents exist, heating new portions of the fresh combustible mixture.

A method of periodically burning a fuel-air mixture without spreading a flame front [15] is based on the forced destruction of metastable molecules of intermediate products of incomplete oxidation of hydrocarbons in the volume of a combustible mixture by means of energy exposure. In this method, when metastable molecules are destroyed, the reaction branches out, a chain explosion quickly develops in the entire volume of the air-fuel mixture, where the molecules were destroyed. Thus, the destruction of metastable molecules functionally replaces the ignition of a fuel-air mixture. The specified method of burning a fuel-air mixture when using a weak shock wave or a stream of electromagnetic radiation as the energy effect is closest to the present invention and is selected as a prototype.

The type of energy effect proposed in [15], associated with the use of a weak shock wave, can be used only in the periodic mode of combustion of the fuel-air mixture under the conditions of an internal combustion engine and cannot be extended to cases of continuous combustion characteristic of burning the fuel-air mixture , for example, in continuous flow mode. Another type of energy effect proposed in [15] by irradiating a combustible mixture with a flux of electromagnetic radiation with a quantum energy sufficient to destroy metastable molecules can, in principle, be used in a continuous combustion mode. However, in the practical application of this type of energy exposure, there are fundamental difficulties associated with creating a source of electromagnetic radiation having the necessary radiation flux density (since each quantum of electromagnetic radiation destroys only one molecule that has absorbed this quantum to destroy the required number of metastable molecules whose specific density in a gaseous environment of less than 3 ÷ 5%, it is necessary to create a radiation flow density of ~ 15 October ÷ October 19 photons / cm 2) and the difficulty of Sintered its efficiency under the conditions of the combustion chamber. At the same time, there are also fundamental difficulties in ensuring uniform illumination of the entire volume of the combustion chamber due to the high absorption coefficient of radiation in a gas medium. For these reasons, it is problematic to put into practice such flare of the combustion zone, which is required for a sufficiently complete and uniform destruction of metastable molecules of intermediate products of incomplete oxidation of hydrocarbons in the fuel combustion zone, and to provide conditions for the rapid development of a radical chain explosion.

The technical result of the present invention is the implementation of an instantaneous reaction of a radical chain explosion in the entire volume of the air-fuel mixture due to the implementation of almost simultaneous destruction of most of the accumulated metastable molecules of the intermediate products, leading to the formation of a large number of active radicals, branching and generating new chains of the oxidation reaction of hydrocarbon fuel. The invention provides an increase in the efficiency of burning hydrocarbon fuels, an increase in the speed of flame propagation and an increase in combustion stability with a continuous mode of fuel combustion, as well as an acceleration of the development of ignition and oxidation of fuel to final products in comparison with known methods for carrying out the combustion of hydrocarbon fuels due to the implementation of a mass branching chain reaction oxidation of hydrocarbon molecules.

To achieve the technical result in the known method of burning hydrocarbon fuel, in which the stimulated destruction of molecules of metastable intermediate products of incomplete oxidation of hydrocarbons accumulated in the gas volume of the air-fuel mixture is realized by energy exposure, it is proposed to enrich the air-fuel mixture with free electrons, and the energy effect on molecules of a combustible mixture to carry out through their inelastic collisions with free electrons, oryaemymi electric field intensity E which is smaller than the voltage transition to independent gas discharge.

The following specific improvements to the method for burning hydrocarbon fuels are also provided:

- enrichment of the fuel-air mixture with free electrons is carried out by its ionization;

- enrichment of the fuel-air mixture with free electrons is carried out by injection of electrons;

- the intensity E of the accelerating electric field is 0.1 ÷ 0.2 part of the electric field strength of the breakdown of the gas gap;

- enrichment of the fuel-air mixture with free electrons and their acceleration by an electric field is carried out pulse, and the pulses of enrichment of the combustible mixture with free electrons coincide in time with the pulses of the accelerating electric field;

- the fuel-air mixture is passed through a zone in which it is continuously enriched with free electrons, and a zone in which free electrons are accelerated in an electric field, while the flow rate of the fuel-air mixture and the geometry of the impact zones are selected so that the lifetime of free electrons exceeds the time between the moment of their formation and the moment of falling into the zone of influence of an accelerating electric field;

- acceleration of free electrons is carried out by an alternating electric field;

- acceleration of free electrons is carried out by an alternating electric field of the microwave range with E eff ~ (1 ÷ 5) · 10 -16 · N V / cm;

- hard electromagnetic radiation containing quanta with energy higher than the ionization potential of at least one of the components of the gas constituting the fuel-air mixture is used as ionizing radiation;

- hard electromagnetic radiation is obtained by means of a sliding electric discharge over the surface of the dielectric with ε≥2;

- as a hard electromagnetic radiation using bremsstrahlung of electrons in the field of "soft x-ray";

- hard electromagnetic radiation in the "soft x-ray" region is obtained by means of a sliding electric discharge over the surface of the dielectric with ε≥2 at the rate of rise of the potential difference on the electrodes dU / dt> 10 12 V / s;

- fast electrons are used as ionizing radiation;

- free electrons are obtained by photoemission when the conductive photoemitter is irradiated with a stream of electromagnetic radiation with a quantum energy of at least the threshold energy of the "exit" of the photoelectrons into the fuel-air mixture.

To implement the method of burning hydrocarbon fuel, a device is proposed comprising a combustion chamber with a source of energy exposure. A feature of the device, in contrast to the prototype, is that the source of energy exposure consists of an accelerating electric field source, including a system of electrodes with controlled switches connected to high-voltage voltage sources, and a device for enriching free electrons in the fuel-air mixture.

The following device variants are provided:

- as a device for enrichment with free electrons of the fuel-air mixture, an ionizing radiation source is used;

- the free electron enrichment device is made in the form of a photoemitter included as a cathode in the electric circuit of the system of electrodes of an accelerating electric field source;

- the combustion chamber is made in the form of a capacitor, the plates of which are the electrodes of the accelerating electric field source, and the free electron enrichment device is placed in the gap between the electrodes;

- the free electron enrichment device consists of two electrodes and sources of electromagnetic radiation, located on the periphery of the interelectrode gap;

- as a high-voltage electrodes of an accelerating electric field source, a sliding discharge plasma of an ionizing radiation source was used;

- the system of electrodes of the source of the accelerating electric field consists of two electrodes with potentials of different sizes, made permeable to the pumped air-fuel mixture and forming an excitation zone of vibrational degrees of freedom of the molecules of the air-air mixture, and the source of free electrons is implemented as an oxidation zone of hydrocarbon-air air hydrocarbons mixture, while the third electrode is introduced into the device with a potential below the lower potential of the two electrodes of the accelerating electric field source, p and the electrode of the electric field source with lower potential is adjacent to the oxidation zone and forms together with the third electrode transfer system of free electrons in a zone of excitation of the vibrational degrees of freedom of the molecules of the fuel-air mixture.

The invention is illustrated by the accompanying drawings.

Figure 1 shows a schematic diagram of a device for implementing a method of burning hydrocarbon fuel with the destruction of metastable molecules by exciting vibrational and rotational degrees of freedom due to inelastic collisions with free electrons moving in an electric field.

Figure 2 shows a diagram of a device for implementing the method in a continuous mode of combustion of the air-fuel mixture.

Figure 3 shows a diagram of a device for implementing the method in a continuous mode of burning a fuel-air mixture when using the oxidation (combustion) zone of hydrocarbons in a fuel-air mixture as a source of free electrons.

Figure 4 shows a diagram of a device when using a source of an accelerating electric field of a plasma of a sliding discharge of an ionizing radiation source as an electrode.

Figure 5 shows a characteristic view of the dependence of the energy loss of electrons per unit path from the energy of electrons.

Figure 6 shows in relative units the effectiveness of various mechanisms of energy loss by electrons depending on the ratio of electric field to pressure for molecular nitrogen [22].

Figure 7 presents the results of calculations of the decay time constant τ of vibrationally excited molecules of hydrogen peroxide N 2 About 2 for the variant molar concentration characteristic of practical systems [20].

The method of burning hydrocarbon fuel is as follows: the prepared air-fuel (oxidizing) mixture 1 is pre-compressed either directly in the combustion chamber bounded by the shell 2, or a compressed mixture is introduced into the volume of the combustion chamber; then the gas mixture is enriched with free electrons by injection or form free electrons directly in the volume of the gas mixture, for example, by partial ionization with the formation of free electrons e - and I + ions using an ionizing radiation source 3 (Fig. 1). Free electrons are accelerated by the electric field created by the electrodes 4 having a voltage E less than the transition voltage to an independent discharge, in particular, the voltage E is 0.1 ÷ 0.2 parts of the value of the gas breakdown voltage.

In the case of periodic combustion of the fuel-air mixture, the moment of injection of free electrons into the fuel-air mixture or the moment of formation of free electrons by ionization of the fuel-air mixture must precede or coincide in time with the action of the electric field, which is created using electrodes 4 placed in the combustion chamber . That is, during all time, or in part of the time of the action of the accelerating electric field in the volume of the fuel-air mixture should be free electrons. Moreover, the duration of the accelerating electric field should be sufficient for the irreversible development of the process of self-ignition of the fuel-air mixture.

Free electrons under the action of an electric field with intensity E acquire enough energy to excite vibrational states of the molecules of the air-fuel mixture 1 by inelastic collisions with these molecules, including molecules of intermediate products of incomplete oxidation of hydrocarbons, including metastable molecules. Excitation of vibrational states of metastable molecules, for example, hydrogen peroxide, facilitates their decomposition into two OH • radicals, which branch a chain reaction of hydrocarbon oxidation, quickly bring the combustible mixture to ignition, and, together with vibrationally excited molecules of other intermediate products of incomplete hydrocarbon oxidation, shorten the reaction time oxidation up to the formation of end products of fuel combustion.

In the case of continuous combustion of the air-fuel mixture (Fig. 2) in a flow mode using a non-self-sustaining electric discharge in a gas to excite vibrational levels in the molecules of the gas medium and stimulate the destruction of metastable hydrogen peroxide molecules, a compressed pre-prepared or a fuel-air mixture prepared in the reactor volume that crosses the flow of penetrating ionizing radiation 3 and / or the free electron injection zone (heating zone scheniya) and falls into the gap between the electrodes 4, to which is applied a potential difference U that creates an electric field between the electrodes of the desired intensity E. In operation, the same processes as in the previous case, but in the continuous time mode. The flow rate of the fuel-air mixture and the geometry of the zones of ionizing and electrical effects on the mixture are selected so that the lifetime of free electrons exceeds the time between the moment of their formation and the moment of falling into the zone of exposure to an electric field.

In the continuous mode of burning the fuel-air mixture, when using the oxidation zone 5 (Fig. 3) of hydrocarbons as the source of free electrons of the fuel-air mixture, the latter is passed along the chamber cavity through gas-permeable electrodes 6 and 7 with potentials of different sizes creating in the gap between electrodes the electric field of the required intensity E for vibrational excitation of molecules. An electrode 6 with a lower potential is adjacent to the oxidation zone 5. The third electrode 8 is at a lower potential than the potential of the electrode 6. The electric potentials of the electrodes 6 and 8 are selected so that the electric field created in the gap between these electrodes draws free electrons, formed in the combustion zone as a result of chemical reactions of fuel oxidation, for example, as a result of a reaction into the gap between the electrodes 6 and 7. After the free electrons e - fall into this gap, they gain energy under the influence of an electric field E and excite vibrational levels of molecules of the incident air-fuel mixture 1. Next, the flow of the combustible mixture 1 with vibrationally excited gets into oxidation zone 5 by molecules, and intensified combustion processes occur in it. The flow of combustion products 9 flows from the combustion chamber. In this method, there is no need to use ignition burners or a combustion stabilizer that creates reverse currents of combustion products that play the role of an ignition device. In fact, since the destruction of metastable molecules functionally replaces ignition, the need for igniting reverse currents of a burning air-fuel mixture disappears. This, as well as the fact that, compared with conventional combustion methods, the rate of combustion of a vibrationally excited fuel-air mixture increases, it can significantly increase the rate of flow of a combustible mixture through a reactor.

In one embodiment of the method, it is proposed to use only electrodes 6 and 8. In this case, the electric potentials of the electrodes are selected so that free electrons are pulled from the oxidation zone 5 by an electric field formed in the gap between the electrodes 6 and 8, and its voltage E is sufficient to excite vibrational degrees of freedom of the molecules of the fuel-air mixture during their collisions with free electrons moving in this field.

It may also be used for the excitation of vibrational degrees of freedom of the molecules of the gas fuel and air mixture nonself microwave discharge, the amplitude of the microwave electric field E which is to be microwave ≤5 E kV / cm · atm. In this case, the radiation parameters are selected so that E eff ~ (1 ÷ 5) · 10 -16 · N V / cm, where E eff = (E microwave / 2 1/2 ) · (1 + ω 2 / ν 2 eff ) -1/2 , where ω is the angular frequency of microwave radiation, ν eff is the effective collision frequency of an electron is a neutral molecule, N is the concentration of molecules of the gas medium.

To enrich the free-air mixture of a fuel-air mixture in sufficient concentration, several modifications of the ionizing radiation source are provided.

In one embodiment of the invention, it is proposed to use a source of hard electromagnetic radiation containing quanta with energy higher than the ionization potential of at least one of the gas components of the fuel-air mixture as a source of ionizing radiation. Such sources of radiation can be: gas discharges of various types, developing directly in an ionized gas medium; gas discharges in a gas medium isolated from the main volume; excimer or other types of lasers having the desired radiation wavelength; other well-known sources of hard electromagnetic radiation. The density of the flux of electromagnetic radiation used for ionization can be reduced by a factor of ~ 10 6 compared to the prototype due to the repeated use of free electrons and due to the "flow" of excitation from nitrogen molecules N 2 , which are long-lived in an excited state, constituting ~ 75% of gas molecules medium, to the molecules of intermediate products of incomplete oxidation of hydrocarbons in the relaxation process during multiple mutual collisions of molecules of the gas medium.

In another embodiment, it is proposed to use soft x-ray radiation with an energy of radiation quanta from a few tens of kiloelectron-volts (keV) to ionize the gas volume of the fuel-air mixture. Such radiation has sufficient penetrating power for relatively uniform ionization of the gas volume characteristic of commonly used combustion chambers. In practice, the implementation of pulsed sources of soft x-ray radiation is possible. Therefore, the implementation option under consideration relates to the use for intermittent combustion of a fuel-air mixture in internal combustion engines.

In particular, a pulsed gas-discharge source of soft X-rays based on runaway electrons can be used. It is possible to satisfy the criterion of "runaway" of electrons in strongly overstressed discharge gaps. In the proposed embodiment, the device shown in FIG. 4 is used. This device consists of two or more electrodes placed on the surface of the dielectric 10 with a dielectric constant ε> 2. As an example of implementation, we describe the operation of a device containing two electrodes. One of the electrodes 11 is placed on the back surface of the dielectric 10 under the other electrode 12 and goes to the front surface, forming a discharge gap 13 on the surface of the dielectric. When a voltage pulse U is applied to the electrodes 11 and 12, the dielectric is polarized in an electric field, forming bound electric charges with a density σ on the surface of the dielectric, which attenuate the electric field inside the dielectric by a factor of ε. Near the electrode 12, where the electric field is maximum, the bound charge on the surface of the dielectric reaches a maximum value. As a result of this, giant local overvoltages arise between the electrode 12 and the surface polarizing charges of the dielectric. As a result of polarization, the insulator “translates” the potential (the surface potential is [(ε-1) / ε] U 11 ) from the lower electrode 11 to the front surface of the dielectric in the immediate vicinity of the electrode 12. For sufficiently fast, dU / dt> 10 12 V / s, an increase in the potential difference U applied to the electrodes 11 and 12, the ions of the gaseous medium do not have time to neutralize the bound charges on the surface of the dielectric and the electric field strength E lock near the electrode 12 reaches values of the order of 10 8 V / cm. With such an electric field, explosive emission of electrons [23] from the surface of the electrode 12 occurs. In this case, the emitted electrons at the initial stage acquire energy w e > w 2 (Fig. 5) and this condition is met for the fulfillment of the “electron runaway criterion”, as well as the condition of continuous electron acceleration is realized up to an energy of several tens of kiloelectron-volts. In the process of their interaction with gas, bremsstrahlung occurs in the soft X-ray region, which carries out the preionization of the gas medium, generating free electrons in the gas volume and preparing the conditions for the excitation of vibrational degrees of freedom of the gas mixture molecules. After an electric field of intensity E is excited in a gas volume , free electrons gain energy and, in inelastic collisions with molecules of a gas medium, excite vibrational degrees of freedom of molecules. An electric field with a strength E y is created in the volume of the air-fuel mixture by a system of electrodes that are connected via controlled switches R and R 1 (Fig. 4) to high-voltage power sources. Structural elements and walls of the combustion chamber can be used as one of the electrodes of the electric field source, and the other electrode is placed on the resistance side of the combustion chamber on a dielectric substrate fixed to one of the structural elements or the wall of the combustion chamber. In one embodiment (Fig. 4), it is proposed to use a sliding discharge plasma as a high-voltage electrode of a source of electric field, which occurs during the development of breakdown of a gas gap over the surface of a dielectric.

In one embodiment of the invention, it is proposed to use a stream of fast electrons, which forms low-energy secondary electrons in the gas, to ionize a gas air-fuel mixture and prepare conditions for the subsequent excitation of vibrational levels of gas molecules. As a source of fast electrons, β-active isotopes or sources of accelerated electrons can be used.

In another embodiment of the invention, it is proposed to use, together with the ionization of the gas air-fuel mixture, during which free electrons are obtained in the volume of the gas medium, an additional source of free electrons. It is proposed to use a photoelectron emitter as an additional source of free electrons. It is proposed to use structural elements and walls of the combustion chamber as an emitter of photoelectrons. The inevitable "contamination" of the inner surface and structural elements of the combustion chamber by films of oxides and other compounds, as a rule, reduce the work function of electrons from the metal surface and therefore do not impede the use of these surfaces as photo emitters. In another embodiment, a specialized photoemitter with a high quantum yield of photoelectrons in the spectral region of exciting electromagnetic radiation λ≈200 ÷ 400 nanometers can be used. For the formation of free electrons, the photoemitter must be "illuminated" using an electromagnetic radiation source having a radiation spectrum with a quantum energy above the threshold of photoemission from this photoemitter, and the emitter must be included in the electric circuit as a cathode. In the proposed embodiment, the cathode of the system of electrodes forming an electric field acting on free electrons can be a photoemitter. In one embodiment, it is proposed to use a sliding discharge plasma over the surface of the dielectric as a source of electromagnetic radiation illuminating the photoemitter with a periodic mode of hydrocarbon combustion. The efficiency of conversion of the stored energy into UV radiation measured in [24] in the spectral range of 250–350 nm was 2%. With a stored energy of ~ 50 millijoules, such a flux of electromagnetic radiation (~ 2 · 10 15 photons) will create ~ 10 12 ÷ 10 14 photoelectrons (free electrons). In the practical implementation of the proposed device enriching the fuel-air mixture with free electrons, the combustion chamber can be made in the form of a capacitor, the "dielectric" of which is the fuel-air mixture, and the "plates" of the capacitor are electrodes of the free electron acceleration system. The role of one of the electrodes, as already indicated, can be performed by structural elements and walls of the combustion chamber. The enrichment device in the form of an ionizing radiation source or an electromagnetic radiation source illuminating the photoemitter can be placed in the gap between the electrodes. In another embodiment, the free electron enrichment device in the form of an ionizing radiation source or an electromagnetic radiation source can be dispersed, for example, have several discharge gaps, and is located on the periphery of the combustion chamber. In this case, the radiation sources are oriented so that the ionizing radiation flux is directed into the gap between the electrodes, and the electromagnetic radiation flux is directed to the photoemitter.

When a sliding discharge plasma is used as field-forming electrodes over the surface of the dielectric, for example, in accordance with the embodiment of FIG. 4, the sliding discharge plasma itself will be an effective source of free electrons. At typical electric field strengths E, the electrons from the "plasma" cathode will be drawn into the fuel-air mixture and carry out the process of excitation of the vibrational states of the molecules of the gaseous medium.

The development of the process of self-ignition of the fuel-air mixture after excitation of vibrational degrees of freedom of the molecules of the gas medium in all cases described in the previous examples of the device (Fig. 1 ÷ 4) occurs according to a similar scenario due to the method of burning hydrocarbon fuel, in which the destruction metastable molecules of intermediate products of incomplete oxidation of hydrocarbons.

A method of burning hydrocarbon fuel, in which the destruction of metastable molecules of intermediate products of incomplete oxidation of hydrocarbons is carried out, consists in the excitation of vibrational degrees of freedom of molecules by inelastic collisions of free electrons moving through the molecular gas of a fuel-air medium under the influence of an electric field. Typically, the air-fuel mixture is approximately 75% nitrogen N 2 molecules. Therefore, free electrons moving through this molecular gas will mainly experience collisions with nitrogen molecules. In inelastic collisions, electrons transfer the energy accumulated between collisions to various degrees of freedom of the molecules. 6: curve 1 shows the fraction of energy transferred per unit time to the excitation of vibrational levels; curve 2 - share on the excitation of electronic levels; curve 3 - for ionization during electron motion through molecular nitrogen with pressure P under the influence of an electric field E. The dependences for other molecular gases have a similar form. From Fig.6 it is seen that when the values of the reduced electric field strength E / P <15 V / cm · Torr, the main mechanism of energy loss by electrons is the excitation of molecular vibrations. During the excitation of molecular gases, such as СО 2 , СО, N 2 , in which the maximum of the excitation cross section for molecular vibrations σ v ≈ 10 -15 cm 2 is located in the range 1 ÷ 2 eV and the cross section decreases sharply with increasing and decreasing electron energy, to 98% of the energy is spent on exciting vibrations. Under the action of inelastic collisions with electrons, nitrogen molecules pass from the lower level v 0 to excited vibrational levels v 1 ÷ 8 . Vibrationally excited nitrogen molecules having a zero dipole moment live for a very long time, and, essentially, the only mechanism for removing their vibrational energy is collisions with unexcited molecules, including molecules of intermediate products. During these collisions, vibrationally excited nitrogen molecules exchange vibrational quanta, which are 0.29 eV, with other molecules. Ultimately, this leads to the excitation of vibrational levels of metastable molecules and other molecules of intermediate products involved in the chain reaction of hydrocarbon oxidation.

Focusing on the main thing, it should be noted that this mechanism is most effective for excitation of vibrational levels of molecules in the ground electronic state. The reason for this is the use of a relatively weak electric field of ~ 3 ÷ 4 kV / cm · atm (kilovolts per centimeter per atmosphere). In such fields, the energy of the electric current is spent almost entirely on the excitation of oscillations, and the fraction of the energy spent on the excitation of electronic levels and ionization is practically zero. A key feature of this application of a non-self-sustaining gas discharge maintained in such electric fields is the volumetric nature of the discharge, which captures the entire volume, where there are free electrons and where the electric field penetrates, and there is no discharge contraction. This is what makes it possible to sufficiently evenly excite the molecules of the gaseous medium and create conditions for volumetric self-ignition of the fuel-air mixture.

Another important for practical applications, the feature of the proposed method is the high efficiency of the use of free electrons. Despite the fact that the gaseous fuel-air mixture in which electrons move is an electronegative medium and the lifetime of free electrons when moving in such a medium is limited not only by the process of recombination with positively charged ions, but also by the processes of adhesion of electronegative components of the gas medium to the molecules, the number of inelastic collisions during the lifetime of a free electron reaches ~ 10 3 ÷ 10 4 . During the time between inelastic collisions, an electron manages to gain an energy of ~ 0.5–1.5 eV. In inelastic collisions, this energy completely goes to the excitation of vibrational levels of molecules. The vibrational energy of molecules after such collisions corresponds to thousands of degrees, and translational energy is in thermal equilibrium with the medium. The high density of vibrationally excited molecules and the long lifetime of the excited states of nitrogen molecules N 2 leads to rapid excitation (mainly by transferring "vibrational quanta" from excited nitrogen molecules N 2 ) to metastable and other molecules of intermediate products of incomplete oxidation of hydrocarbons directly involved in the reactions oxidation.

Taking into account vibrational excitation to the corresponding vibrational energy E v , the rate constant k 1, v (T; E v ) of reaction (2) for vibrationally excited molecules can be represented as:

where m 1 = 1.2 · 10 17 is the preexponential factor of the reaction rate constant (2), α is the coefficient of use of vibrational energy. It is seen that for vibrationally excited molecules with energy E v, the activation barrier decreases as if by a value of α · E v .

For the case of the monomolecular reaction of spontaneous dissociation of hydrogen peroxide (2), the value of α≅1. The results of calculations of the decay time constant of vibrationally excited metastable Н 2 О 2 molecules, performed using expression (6), show that the excitation of vibrational levels significantly expands the range of operating temperatures at which a fast one is possible (for example, τ <0.5 · 10 -3 sec) process of self-ignition of the prepared air-fuel mixture. And, most importantly, before the vibrational levels of self-ignition are excited, the air-fuel mixture does not occur due to insufficient temperature, and after the fast process of vibrational levels excitation (less than 1 μs), self-ignition develops almost instantly. Thus, an effective remote “mechanism” (actually a trigger) of self-ignition process control appears. The presented family of curves corresponding to the excitation levels of vibrational states up to an energy of 0.1 ÷ 1.5 eV, when compared with the curve "A", the corresponding dependence of the decay time constant τ 0 of Н 2 О 2 molecules on temperature in Kelvin, is located strongly "on the left", which means achieving the same decay rate at significantly lower temperatures. When using the proposed method, for example, in an internal combustion engine, the air-fuel mixture is compressed in a compression stroke, while the temperature of the combustible mixture rises, the pressure rises, chain reactions of low-temperature multi-stage self-ignition occur, during which metastable Н 2 О 2 molecules are formed and accumulate and other molecules of intermediate products of incomplete oxidation of hydrocarbons. As an example, we consider the case when the engine operates in such a mode that after the compression stroke the temperature of the fuel-air mixture is 850 K. The decay time constant of metastable H 2 O 2 molecules corresponding to this state of the fuel-air mixture is on curve “A” at the point A 1 (Fig.7). It can be seen that τ A1 ~ 3 · 10 -2 sec and we cannot speak of any self-ignition of the fuel-air mixture near the "top dead center". Usually in such and similar (when τ is large) cases, the combustible mixture is ignited with a spark plug. (In practice, in internal combustion engines with compression of the prepared fuel-air mixture, the combustible mixture is always ignited with one or another lead near the top dead center). In contrast, in the proposed method at an instant corresponding to the “top dead center”, an energetic effect is applied to the fuel-air mixture, which leads to the excitation of vibrational levels of the molecules of the gaseous medium. After that, during the relaxation process, in a period of less than 10 -6 sec, predominantly excited N 2 nitrogen molecules transfer the excitation energy to the molecules of intermediate products and, ultimately, excite vibrational degrees of freedom in almost all accumulated H 2 O 2 molecules. As a result of the excitation of vibrational states of metastable molecules, the decay time constant τ decreases sharply. The values of τ for different temperatures and excitation energies of vibrational levels of H 2 O 2 molecules can be found using the family of curves shown in Fig. 7. In the presented case, the decay time "acceptable" for practical use is ~ 5 · 10 -4 sec and, accordingly, the development time of the self-ignition of the air-fuel mixture will correspond to the excitation energy E v ≥0.3 eV, equal to the energy obtained by the exchange of one quantum of vibrational energy of the excited nitrogen molecule N 2 . Thus, it can be seen from FIG. 7 that stimulated self-ignition of the fuel-air mixture in internal combustion engines is possible for all essential engine operating modes.

It is also possible the development of self-ignition of the fuel-air mixture in a different way. The “high-temperature” branching reaction (3) has an activation energy of 70.3 kJ / mol and can play a significant role for the development of the self-ignition process only at temperatures above 1100–1200 K. However, estimates made using expressions of the type (6) for the “high-temperature” reaction branchings (3) show that after the vibrational levels of the molecules of the gaseous medium are excited, the effective temperature of the chain branching process along this path decreases by ~ 300 ÷ 500 K. For this reason, such a mechanism with movosplameneniya, wherein immediately after the excitation of vibrational levels of the molecules of the gaseous medium developing kinetically simple and weakly dependent on the fuel process chain branching by reaction (3).

An essential kinetic feature of the proposed method for burning hydrocarbon fuel is that when it is used due to the strong disequilibrium of the reaction system, when the "vibrational" temperature of the excited molecules corresponds to thousands of degrees, and the "translational" temperature practically does not change compared to the initial one (meaning the beginning of the process of excitation of vibrational degrees of freedom of molecules) by the value, as if the "degenerate" nature of the branching of the chain reaction is removed. This means that the emergence of new molecules of the "precursor" of the formation of peroxide molecules - molecules, is not blocked. which continue to form in the fuel-air mixture and provide peroxide molecules during the reaction Thus, at the initial stages of the development of self-ignition after vibrational excitation of molecules, the branching process can occur simultaneously both in reaction (2) and in reaction (3). When the energy of the molecules becomes sufficient during the oxidation of hydrocarbons with the participation of vibrationally excited molecules of intermediate products, the branching mechanism of the chain oxidation process proceeds to reaction (3).

The branching reaction (3) is also the main branching reaction during the combustion of the hydrogen-oxygen system [25]. Therefore, the proposed method of burning fuel can be used to burn hydrogen fuel, for example, in internal combustion engines, rocket engines or other power plants that use hydrogen as fuel.

When implementing the proposed method of combustion, the self-ignition process develops synchronously in the entire volume of the fuel-air mixture that has been subjected to energy impact. This eliminates the possibility of a phenomenon called “knocking” that occurs when the last portions of unburned air-fuel mixture (exhaust gases) spontaneously ignite in a known working process in a spark ignition engine. In the process of development of volumetric self-ignition of a combustible mixture, the very concept of exhaust gases loses its meaning, since almost the entire combustible mixture goes through the stage of self-ignition synchronously in time. At the same time, the speed and completeness of fuel combustion also increases both due to a faster increase in the number of destroyed metastable molecules, and due to a decrease in the effective activation energy of endothermic reactions along the entire length of the main chain of the hydrocarbon oxidation reaction. All this allows to raise the compression ratio of the fuel-air mixture in gasoline internal combustion engines when using standard grades of gasoline to r> 15. The criterion for assessing the permissible degree of compression when using this type of fuel is the restriction on the temperature of the fuel-air mixture during compression. This temperature should not exceed the “top dead center” value at which thermal decomposition of hydrogen peroxide molecules occurs at a noticeable rate. That is, the temperature and pressure of the air-fuel mixture at the end of the compression stroke, as well as the fuel must be such that the delay time for the self-ignition of the fuel mixture is longer than the duration of the last 20 ° ÷ 30 ° before the "top dead center" in the crankshaft rotation angle. Conditionally, the value of ~ 900 K can be taken as the boundary temperature for standard grades of gasoline at all practically significant operating modes of the automobile engine [26].

The use of the proposed method of burning hydrocarbon fuel as applied to internal combustion engines, in addition to the above-mentioned advantages associated with increasing the compression ratio, increasing the speed and completeness of fuel combustion and, therefore, reducing the toxicity of exhaust gases and increasing fuel economy, also has additional advantages. One of the most important is the increase in the efficiency (efficiency) of the conversion of thermal energy into mechanical energy compared to engines using spark ignition, due to the elimination of additional back pressure on the piston that occurs when part of the fuel charge is burned to the “top dead center” during completion compression stroke.

A significant advantage of the proposed method of burning hydrocarbon fuel as applied to internal combustion engines is the reduction in the content of harmful emissions of nitrogen oxides NO x , where x <2, due to the "oxidation" of NO x molecules to NO 2 molecules, which are then quite effectively restored in the catalytic converter to the starting products N 2 and O 2 . The process of “oxidation” occurs in the combustion chamber due to the fact that NO x molecules formed during the combustion of the air-fuel mixture are also exposed to energy from the side of accelerated free electrons and are in a vibrationally excited state. In this case, the effective energy of NO x molecules exceeds the activation energy of the “oxidation” reaction, resulting in NO 2 molecules.

The advantages of the proposed method for continuously burning hydrocarbon fuel over known combustion methods are the following factors: increasing the speed and completeness of fuel combustion, which allows to increase the maximum amount of the air-fuel (oxidizing) mixture passed through the reactor, and therefore, to improve the power characteristics of the power plant; the possibility of increasing the flow rate of the combustible mixture; an opportunity to do without combustion stabilizers; the ability to do without igniting burners; increasing the stability of fuel combustion.

Information Sources Used

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Claims

1. A method of burning hydrocarbon fuel, in which they realize stimulated destruction of molecules of metastable intermediate products of incomplete oxidation of hydrocarbons accumulated in the gas volume of the fuel-air mixture by means of energy exposure, characterized in that the air-fuel mixture is enriched with free electrons, and the energy effect on the molecules mixtures are carried out by means of their inelastic collisions with free electrons accelerated by an electric field, the intensity E of which is less tension transition to an independent gas discharge.

2. The method of burning hydrocarbon fuel according to claim 1, characterized in that the enrichment of the fuel-air mixture with free electrons is carried out by its ionization.

3. The method of burning hydrocarbon fuel according to claim 1, characterized in that the enrichment of the fuel-air mixture with free electrons is carried out by injection of electrons.

4. The method of burning hydrocarbon fuel according to claim 1, characterized in that the electric field E is 0.1-0.2 parts of the electric field breakdown of the gas gap.

5. The method of burning hydrocarbon fuel according to claim 1, characterized in that the enrichment of the fuel-air mixture with free electrons and their acceleration by an electric field is carried out pulse, and the pulses of enrichment of the combustible mixture with free electrons coincide in time with the pulses of the accelerating electric field.

6. The method of burning hydrocarbon fuel according to claim 1, characterized in that the air-fuel mixture is passed through a zone in which it is continuously enriched with free electrons, and a zone in which free electrons are accelerated in an electric field, while the flow rate of the fuel -the air mixture and the geometry of the zones of influence are selected so that the lifetime of free electrons exceeds the time between the moment of their formation and the moment of getting into the zone of influence of an accelerating electric field.

7. The method of burning hydrocarbon fuel according to claim 1, characterized in that the acceleration of free electrons is carried out by an alternating electric field.

8. The method of burning hydrocarbon fuel according to claim 1, characterized in that the acceleration of free electrons is carried out by an alternating electric field of the microwave range with E eff ~ (1 ÷ 5) · 10 -16 · N V / cm, where N is the concentration of molecules of the gas medium .

9. The method of burning hydrocarbon fuel according to claim 2, characterized in that hard ionizing radiation containing quanta with energy higher than the ionization potential of at least one of the components of the gas constituting the air-fuel mixture is used as ionizing radiation.

10. The method of burning hydrocarbon fuel according to claim 9, characterized in that hard electromagnetic radiation is obtained by means of a sliding electric discharge over the surface of a dielectric with ε≥2.

11. The method of burning hydrocarbon fuel according to claim 9, characterized in that the bremsstrahlung of electrons in the "soft x-ray" region is used as hard electromagnetic radiation.

12. The method of burning hydrocarbon fuel according to claim 11, characterized in that hard electromagnetic radiation in the soft x-ray region is obtained by means of a sliding electric discharge over the surface of the dielectric with ε≥2 at a rise rate of potential difference across the electrodes dU / dt> 10 12 .

13. The method of burning hydrocarbon fuel according to claim 2, characterized in that fast electrons are used as ionizing radiation.

14. The method of burning hydrocarbon fuel according to claim 3, characterized in that free electrons are obtained by photoemission when the conductive photoemitter is irradiated with a stream of electromagnetic radiation with a quantum energy of at least a threshold energy for the "exit" of photoelectrons to the air-fuel mixture.

15. A device for implementing a method of burning hydrocarbon fuel containing a combustion chamber with a source of energy, characterized in that the source of energy consists of a source of an accelerating electric field, including a system of electrodes with controllable switches connected to high voltage sources, and a free electron enrichment device fuel-air mixture.

16. The device according to clause 15, wherein a source of ionizing radiation is used as a device for enrichment with free electrons of the fuel-air mixture.

17. The device according to clause 15, wherein the free electron enrichment device is made in the form of a photoemitter included as a cathode in the electric circuit of the electrode system of the accelerating electric field source.

18. The device according to clause 15, wherein the combustion chamber is made in the form of a capacitor, the plates of which are electrodes of an accelerating electric field source, and the free electron enrichment device is located in the gap between the electrodes.

19. The device according to clause 15, wherein the free electron enrichment device consists of two electrodes and electromagnetic radiation sources located on the periphery of the interelectrode gap.

20. The device according to p. 15, characterized in that as the high-voltage electrodes of the source of the accelerating electric field, a sliding discharge plasma of the ionizing radiation source is used.

21. The device according to p. 15, characterized in that the electrode system of the accelerating electric field source consists of two electrodes with potentials of different sizes, made permeable to the pumped air-fuel mixture and forming an excitation zone of vibrational degrees of freedom of the fuel-air mixture molecules, and the source of free electrons is implemented in the form of a zone of hydrocarbon oxidation of a fuel-air mixture, while a third electrode with a potential lower than the lower potential of two electrodes nick accelerating electric field, the electric field supply electrode with lower potential is adjacent to the oxidation zone and forms together with the third electrode transfer system of free electrons in a zone of excitation of the vibrational degrees of freedom of the molecules of the fuel-air mixture.