RU2513527C1 - Gas turbine engine combustion chamber and method of its operation - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed combustion chamber comprises housing accommodating the perforated fire tube with combustion and dilution zones, fuel feed system, air primary and secondary flow feed system and fuel-air mix ignition system. Airflow feed system incorporates primary airflow controller in primary air channel and secondary airflow controller inside circular channel between combustion chamber walls and fire tube. Said controllers include laser radiation source, laser radiation splitter for primary and secondary airflows controllers. Every said controller incorporates optic fibres with inputs connected to laser radiation splitter. Output of primary airflow controller optic fibre is connected via through hole with primary airflow inlet channel equipped with at least two opposed mirrors. Secondary airflow controller comprises at least two opposed mirrors located inside circular channel, one of the mirrors having a through hole at mirror axis in focal plane. Output of secondary airflow controller optic fibre is connected via mirror through hole with circular channel. Laser source can excite oxygen molecules to metastable singlet states.

EFFECT: higher completeness of combustion and chamber efficiency.

16 cl, 3 dwg

Description

The invention relates to aircraft engine building, in particular to methods for organizing combustion in the combustion chambers of aircraft gas turbine engines (GTE).

A known method of organizing combustion in a traditional combustion chamber of an aircraft gas turbine engine, widely used in the main combustion chambers of a gas turbine engine of a traditional design, regardless of the specific design features of the engine. The method consists in the fact that the working volume of the chamber is divided into two main parts: the combustion zone and the dilution zone. Behind the front device of the flame tube, gas circulation zones are formed, which are necessary for stabilization of the flame, i.e. for continuous ignition of the air-fuel mixture by hot combustion products. The fuel sprayed by the centrifugal nozzle is fed into this zone. The air entering the flame tube is divided into three main parts: primary, secondary and tertiary (see, for example, “Providing a set of basic characteristics of the chamber.” Main combustion chambers of gas turbine engines. Scientific contribution to the creation of aircraft engines, Book 2, TsIAM, 2000 ., pp. 308-309).

The disadvantage of this method is the high level of emission of pollutants, which, as you know, include: carbon monoxide СО, nitrogen oxides NO _x , unburned hydrocarbons С _n Н _m and soot particles that are formed during the combustion of hydrocarbon fuels in traditional gas turbine combustion chambers.

A gas turbine engine combustion chamber is known in which steam is used to reduce toxic emissions (RF patent No. 2287066, IPC F01K 21/04, publ. 2006). The method of operation of the specified chamber of the gas turbine engine includes supplying steam to the primary zone (combustion zone) and to the secondary zone (dilution zone) of the combustion chamber. The flow rate of steam into the primary zone is controlled by transferring part of the steam into the secondary zone and the optimum flame temperature in the primary zone is maintained in all main operating modes. In this case, the steam in the secondary zone is supplied directly to the combustion tube of the combustion chamber without preliminary mixing with the air supplied to the secondary zone. The invention allows to ensure under all operating conditions in the range of main operating modes a low level of emission of nitrogen oxides, carbon monoxide and unburned hydrocarbons, stable and reliable operation of the combustion chamber, a significant increase in power and efficiency installation.

The main disadvantage of this combustion chamber is the impossibility of its use in aircraft engines due to the large amount of steam required and the lack of a steam source on board the aircraft.

In connection with the stricter requirements for the emission of harmful substances from gas turbine engines, there is a need to develop a combustion chamber with low emissions of these substances. Among other solutions (steam or water supply to the combustion chamber), redistribution of air flow along the length of the combustion chamber is used to ensure optimal combustion conditions in the entire working range of gas turbine engine operating modes. At the same time, to prevent the formation of CO and C _n H _m at low conditions and to ensure normal start-up of the combustion chamber, the air flow to the primary zone is reduced, and at high conditions to prevent the formation of NO _x , the air flow to the primary zone is increased.

Closest to the proposed chamber is a gas turbine engine with a controlled distribution of air, containing a fire tube with windows in its wall, overlapped by a movable element located at the location of the windows, connected through a lever system with a drive (patent EP 0100135, IPC F23R 3/26, publ . 1986).

The disadvantage of this device is its low reliability, since when heating the walls of the flame tube, the rings rotated and moved along it, the belts either do not provide tightness (when closed), which violates the optimal distribution of air along the length of the flame pipe, or (with sufficient tightness, t .e. with small gaps), failures in the movements of the regulating elements can occur due to warping of the flame tube, especially when it is unevenly heated, and from temperature expansion of the flame tube and adjustable lementov.

As noted above, in a traditional combustion chamber, the air drawn from the compressor is divided into two streams: primary and secondary streams. The primary stream enters the front-end device, which contains the fuel nozzle and ensures, with the help of the main and auxiliary swirlers, the creation of a turbulent flow of the gas mixture by mixing primary air with fuel. The formed air-fuel mixture ignites in a standard way and forms a flame plume in the flame tube in the direction of gas flow with a maximum temperature on the axis of the order of 2000 K or more. The high temperature of the flame torch causes the formation of nitrogen oxides in it, which, along with carbon oxides, are the main pollutants in the combustion chamber. The formation of CO in the combustion products is a consequence of incomplete combustion of hydrocarbon fuels in the region of the side wall of the flame tube, which is intensively cooled to 900 K in the narrow zone of supply of the secondary air sheet located between the body of the combustion chamber and the outer surface of the flame tube. At such a low temperature, carbon monoxide does not oxidize to CO ₂ . Thus, the reasons for the formation of nitrogen and carbon oxides are different, which explains the practical difficulties in the technical implementation of the simultaneous prevention of these contaminants in the exhaust gases of the gas turbine combustion chamber. The reduction of nitrogen oxides is carried out by burning lean mixtures, which may relate to some equivalent decrease in the effective residence time of the main combustion products in the area of intense heat generation. However, this approach is not optimal, since it is accompanied by problems of combustion instability compared with diffusion combustion, which is the main disadvantage and obstacle in creating combustion chambers using lean mixtures.

The present invention is based on the following tasks:

- acceleration of the combustion process while reducing emissions of harmful substances, including NO _x and CO;

- oxidation of CO to CO ₂ , which reduces the emission of CO from the combustion chamber by several times and thereby provides an environmentally friendly level of CO emission from the engine;

- increase the completeness of combustion of the air-fuel mixture and efficiency combustion chambers;

- providing cleaner burning.

To achieve the technical result, the gas turbine engine combustion chamber comprises a housing, a perforated flame tube located in the housing with combustion and dilution zones, a fuel supply system, a primary and secondary air flow supply system, and an air-fuel mixture ignition device. The air flow supply system is equipped with a device for influencing the primary air flow in the primary air inlet channel and a device for influencing the secondary air flow in the annular cavity cavity between the walls of the combustion chamber and the flame tube.

и $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

.New in the invention is that devices for influencing the flows of primary and secondary air contain a laser source and a laser divider for devices affecting the flows of primary and secondary air. Each exposure device is equipped with optical fibers with inputs connected to a laser radiation divider. The output of the optical fiber of the device for influencing the primary air flow is connected through a through hole to the input channel of the primary air, made with at least two mirrors located opposite each other. The device for influencing the secondary air flow contains at least two opposing mirrors located in the cavity of the annular channel, where one of the mirrors has a through hole in the focal plane on the axis of symmetry. The output of the optical fiber of the device for influencing the secondary air flow is connected through the through hole of the mirror to the annular channel. The laser radiation source is configured to excite oxygen molecules in metastable singlet states $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

and $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

.

Also new is the fact that the mirrors in the inlet channel of the primary air are made in the form of separate flat polyhedra.

Also new is the fact that the mirrors are located in the cavity of the annular channel covering the combustion zone or the dilution zone of the flame tube.

The method of operation of the combustion chamber of a gas turbine engine is that fuel and air are separately supplied to the combustion chamber. The air flow is divided into two parts. In this case, the primary air flow is affected, mixed with fuel and ignited in the cavity of the flame tube. The secondary air stream is exposed and supplied through openings in the wall of the combustion tube combustion chamber.

и $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

.New in the invention is that the impact on the flows of primary and secondary air is carried out by laser radiation with the possibility of excitation of oxygen molecules in metastable singlet states $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

and $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

.

Also new is the fact that when exposed to laser radiation on the flows of primary and secondary air, a uniform, isotropic light field is formed, providing multiple reflection of laser radiation between the mirrors.

It is also new that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel, covering the combustion zone or the dilution zone of the flame tube.

и $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

описан в следующих статьях: 1) Adam Hicks, Seth Norberg, Paul Shawcross, Walter R Lempert, J William Rich and Igor V Adamovich. Singlet oxygen generation in a high pressure non-self-sustained electric discharge//J. Phys. D: Appl. Phys. 38 (2005) 3812-3824; 2) K.F.Pliavaka, S.V.Gorbatov, S.V.Shushkou, F.V.Pliavaka, A.P.Chemukho, S.A.Zhdanok, V.V.Naumov, A.M. Starik, A. Bourig, J.-P. Martin. Singlet oxygen production in electrical non-self-sustained HV pulsed+DC cross discharge at atmospheric pressure with application to plasma assisted combustion technologies//In Contributed Papers of International Workshop on Nonequilibrium Processes in Combustion and Plasma Based Technologies, page 186-191, Minsk, 2006.The mechanism of influence on the air flow with the possibility of providing excitation of molecular oxygen to singlet states $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

and $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

described in the following articles: 1) Adam Hicks, Seth Norberg, Paul Shawcross, Walter R Lempert, J William Rich and Igor V Adamovich. Singlet oxygen generation in a high pressure non-self-sustained electric discharge // J. Phys. D: Appl. Phys. 38 (2005) 3812-3824; 2) KFPliavaka, SV Gorbatov, SVShushkou, FVPliavaka, APChemukho, SAZhdanok, VVNaumov, AM Starik, A. Bourig, J.-P. Martin Singlet oxygen production in electrical non-self-sustained HV pulsed + DC cross discharge at atmospheric pressure with application to plasma assisted combustion technologies // In Contributed Papers of International Workshop on Nonequilibrium Processes in Combustion and Plasma Based Technologies, page 186-191, Minsk , 2006.

The present invention is based on the following physical processes for reducing the concentration of nitric oxide and carbon oxides.

It is known that a noticeable decrease in nitrogen oxides can be realized by burning poor hydrocarbon air mixtures, which are characterized by the parameter ϕ equal to the ratio of the mass of fuel to the mass of oxidizer (air) and is called the coefficient of excess fuel (fuel). For ϕ = 1, the mixture is stoichiometric, and for ϕ <1, the mixture is poor, and vice versa. The acceleration of the combustion process can be achieved by using oxygen molecules in excited metastable singlet states. The corresponding detailed kinetic mechanism of such combustion is described in: Starik A.M., Koslov V.E., Titova N.C. // Combust. Flame 2010. V.157. N2. P.313-327.

в смеси СH₄ - воздух была разработана расширенная кинетическая модель. Оценки констант скорости для реакций N(⁴S)+ $$O_2(a^1{\Delta }_g)$$

=NO(X²П)+O(³P) и N²+ $$O_2(a^1{\Delta }_g)$$

=N₂O+O(¹D), основанные на вычислениях поверхностей потенциальной энергии, показали, что активность молекул синглетного кислорода в этих реакциях намного меньше, чем молекул кислорода в основном состоянии. Однако присутствие дополнительного количества синглетного кислорода в смеси СН₄ - воздух приводит к увеличению концентрации NO. Тем не менее, это увеличение не превышает 30% даже при $${\lambda }_{O_2(a^1{\Delta }_g)}^0=\mathrm{0,05}{\gamma }_{O_2}^0$$

. Главная причина этого явления - появление дополнительного количества атомарного кислорода в горячей и холодной областях пламени вследствие ускорения разветвления цепи при наличии синглетного кислорода в смеси СН₄ - воздух. Более быстрое образование атомов О увеличивает производство молекул NО в ходе реакции N₂+О=NO+N, входящей в тепловой механизм. Поскольку присутствие возбужденных молекул O₂ в смеси СН₄ - воздух приводит к росту скорости пламени и расширению пределов воспламенения, становится возможным сжигание более бедной смеси, по сравнению со случаем отсутствия молекул $$O_2(a^1{\Delta }_g)$$

в газе, при одинаковом значении скорости пламени. Это позволяет значительно уменьшить концентрацию оксида азота в продуктах сгорания.To analyze the processes of NO _x formation in the presence of singlet oxygen molecules $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

In the CH ₄ - air mixture, an extended kinetic model was developed. Estimates of the rate constants for the reactions N ( ⁴ S) + $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

= NO (X ² P) + O ( ³ P) and N ² + $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

= N ₂ O + O ( ¹ D), based on calculations of potential energy surfaces, showed that the activity of singlet oxygen molecules in these reactions is much less than the oxygen molecules in the ground state. However, the presence of an additional amount of singlet oxygen in the mixture of CH ₄ - air leads to an increase in the concentration of NO. However, this increase does not exceed 30% even at $${\lambda }_{O_2(a^{\mathrm{one}}{\Delta }_g)}^0=0.05{\mathrm{<figure-callout\; id="2"\; label="\gamma \; O"\; filenames="00000014.png"\; state="\{\{state\}\}">\gamma \; </figure-callout>}}_{O_{}}^{{}_2}$$

. The main reason for this phenomenon is the appearance of an additional amount of atomic oxygen in the hot and cold regions of the flame due to accelerated branching of the chain in the presence of singlet oxygen in the mixture of CH ₄ air. Faster formation of O atoms increases the production of NO molecules during the reaction N ₂ + O = NO + N, which is part of the thermal mechanism. Since the presence of excited O ₂ molecules in the CH ₄ - air mixture leads to an increase in the flame velocity and expansion of the ignition limits, it becomes possible to burn a poorer mixture compared to the case of the absence of molecules $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

in gas, at the same flame speed. This can significantly reduce the concentration of nitric oxide in the combustion products.

уменьшение концентрации NО для атмосферного пламени метан - воздух из-за горения более бедной смеси может достигать двух раз (ст.: A.M.Starik, P.S.Kuleshov, A.S.Sharipov, V.A.Strelnikova, N.S.Titova. On the influence of singlet oxygen molecules on the NO_x formation in methane-air laminar flame. Proceedings of the Combustion Institute, 2012, V.34, doi l0.1016/j.proci. 2012.10.003).So, with $${\lambda }_{O_2(a^{\mathrm{one}}{\Delta }_g)}^0=0.05{\mathrm{<figure-callout\; id="2"\; label="\gamma \; O"\; filenames="00000014.png"\; state="\{\{state\}\}">\gamma \; </figure-callout>}}_{O_{}}^{{}_2}$$

a decrease in the concentration of NO for the atmospheric flame of methane - air due to the burning of a poorer mixture can reach two times (Art .: AMStarik, PSKuleshov, ASSharipov, VAStrelnikova, NSTitova. On the influence of singlet oxygen molecules on the NO _x formation in methane-air laminar flame. Proceedings of the Combustion Institute, 2012, V.34, doi l0.1016 / j.proci. 2012.10.003).

. Далее в результате относительно быстрого тушения состояния $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

: $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

+М= $$O_2(a^1{\Delta }_g)$$

+М в воздухе возникает метастабильное состояние $$O_2(a^1{\Delta }_g)$$

. Молекулы синглетного кислорода $$O_2(a^1{\Delta }_g)$$

реагируют с молекулами СО на несколько порядков величины быстрее, чем молекулы О₂ в основном электронном состоянии (Sharipov A.S. and Starik A.M. // J. Phys. Chem. A.2011. V.115. P.1795-1803). Поступая вместе с вторичным воздухом в пристеночную область жаровой трубы с относительно низкой температурой (Т=900-1000 К), синглетный кислород $$O_2(a^1{\Delta }_g)$$

инициирует протекание цепного механизма, приводящему к быстрому окислению СО до СО₂. При этом уменьшается эмиссия СО из камеры сгорания в несколько раз и достигается экологически безопасный уровень эмиссии. Увеличиваются полнота сгорания топливовоздушной смеси и к.п.д. камеры сгорания в целом.Unlike nitric oxide, carbon monoxide in a traditional chamber is formed as a result of lowering the temperature in a narrow zone of supply of a secondary air sheet in the region between the outer surface of the flame tube and the housing of the combustion chamber. The formation of CO in the combustion products is a consequence of the incompleteness of the combustion of hydrocarbon fuels in this low-temperature region, which is intensively cooled to 900 K in a narrow zone of supply of a shroud of secondary air. At such a low temperature, carbon monoxide does not oxidize to CO ₂ . The intensification of the oxidation of CO to CO ₂ in the low-temperature region is achieved by excitation of O ₂ molecules from the ground to an excited electronic state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

. Further, as a result of relatively quick quenching of the state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

: $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

+ M = $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

+ M in the air there is a metastable state $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

. Singlet oxygen molecules $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

react with CO molecules several orders of magnitude faster than O ₂ molecules in the ground electronic state (Sharipov AS and Starik AM // J. Phys. Chem. A.2011. V.115. P.1795-1803). Entering together with the secondary air in the wall region of the flame tube with a relatively low temperature (T = 900-1000 K), singlet oxygen $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

initiates the occurrence of a chain mechanism leading to the rapid oxidation of CO to CO ₂ . In this case, the emission of CO from the combustion chamber is reduced several times and an environmentally friendly level of emission is achieved. The completeness of combustion of the air-fuel mixture and efficiency is increasing. combustion chambers in general.

Thus, the tasks of the invention are solved in comparison with the known analogues.

(сплошная и пунктирная линии при значениях: Р₀=1 атм, Т₀=300 К); на фиг.3 изображен график, где мольная доля NО на расстоянии 10 см от фронта ламинарного пламени для смеси СH₄ - воздух с Р₀=1 атм, Т₀=300 К и различных значениях ϕ при $${\lambda }_{O_2(a^1{\Delta }_g)}^0=0$$

и $$\mathrm{0,05}{\gamma }_{O_2}^0$$

(белые и черные колонки, соответственно). Для рассматриваемых случаев над каждой колонкой указаны значения конечной адиабатной температуры в продуктах сгорания.The present invention is illustrated by the following detailed description of the gas turbine engine combustion chamber and the method of its operation with reference to the drawings shown in figures 1-3, where Fig.1 is a diagram of a gas turbine engine combustion chamber; figure 2 is a graph of the dependence of the velocity of the laminar flame U _n in a mixture of CH ₄ - air on the value of the coefficient of excess fuel (ϕ) for a lean mixture at $${\lambda }_{O_2(a^{\mathrm{one}}{\Delta }_g)}^0=0\mathrm{and}0.05{\mathrm{<figure-callout\; id="2"\; label="\gamma \; O"\; filenames="00000014.png"\; state="\{\{state\}\}">\gamma \; </figure-callout>}}_{O_{}}^{{}_2}$$

(solid and dashed lines at values: P ₀ = 1 atm, T ₀ = 300 K); figure 3 shows a graph where the molar fraction of NO at a distance of 10 cm from the front of the laminar flame for a mixture of CH ₄ - air with P ₀ = 1 ATM, T ₀ = 300 K and various values of ϕ at $${\lambda }_{O_2(a^{\mathrm{one}}{\Delta }_g)}^0=0$$

and $$0.05{\mathrm{<figure-callout\; id="2"\; label="\gamma \; O"\; filenames="00000014.png"\; state="\{\{state\}\}">\gamma \; </figure-callout>}}_{O_{}}^{{}_2}$$

(white and black columns, respectively). For the cases under consideration, values of the final adiabatic temperature in the combustion products are indicated above each column.

On the diagram of the combustion chamber of a gas turbine engine (figure 1), the following notation:

one flame tube; 2 combustion chamber body; 3 fuel supply system; four source of laser radiation; 5 mirrors placed in the cavity of the annular channel; 6 optical fiber; 7 optical fiber input; 8 openings for supplying secondary air; 9 circulation flows in the combustion chamber; 10 annular cavity cavity; eleven ignition device; 12 primary air flow; 13 secondary air flow; fourteen laser divider; fifteen primary air inlet 16 mirrors in the primary air inlet.

The gas turbine combustion chamber contains a housing 2, a perforated flame tube 1 with combustion zones and dilution zones 2, a fuel supply system 3, a primary and secondary air flow system 12, 13, and an air-fuel ignition device 11 (see FIG. 1). The GTE combustion chamber is equipped with a device for influencing the primary air stream 12 in the primary air inlet 15 and a device for influencing the secondary air stream 13 in the cavity 10 of the annular channel between the walls of the combustion chamber and the flame tube 1. Devices for influencing the primary and secondary air flows 12, 13 comprise a laser radiation source 4 and a laser radiation divider 14 according to devices for influencing the primary and secondary air streams 12, 13. Each exposure device is equipped with optical fibers 6 with inputs connected to a laser divider 14. The output (not shown) of the optical fiber 6 of the device for influencing the primary air stream 12 is connected through a through hole (not shown) to the input air channel 15 of the primary air made with at least two mirrors 16 opposite each other 16. The device for influencing the stream 13 The secondary air contains at least two opposing mirrors 5 located in the cavity 10 of the annular channel, where one of the mirrors 5 has a through hole in the focal plane on the axis of symmetry (not shown). The output (not shown) of the optical fiber 6 of the device for influencing the secondary air stream 13 is connected through the through hole of the mirror 5 to the cavity 10 of the annular channel, and the laser radiation source 4 is configured to excite oxygen molecules in metastable singlet states.

. Выделение соответствующего спектрального диапазона излучения, которое вызывает указанный переход, можно осуществить стандартным методом с помощью монохроматора либо отдельной дифракционной отражательной решетки, установленной на пути излучения, выходящего из кристалла Al₂O₃Ti³⁺, и отражением выделенного решеткой спектра в область протекания реакции горения между внешней поверхностью жаровой трубы 1 и стенкой корпуса 2 камеры сгорания. Многократное отражение лазерного излучения между зеркалами 5, 16 формирует однородное, изотропное световое поле. Однородное световое поле обеспечивает интенсификацию воздействия лазерного излучения на обрабатываемый воздух. Возможность осуществления подобной оптической схемы подтверждается результатами исследований (ст.: Н.И.Липатов, А.С.Бирюков, Э.С.Гулямова. Световой котел-генератор синглетного кислорода $$O_2(a^1{\Delta }_g)$$

// Квантовая электроника. 2008. Т.38. №13. C.1179-1182).The laser radiation source 4 can be made in the form of a solid-state Nd: YAG laser, the main frequency of which is converted by an Al ₂ O ₃ Ti ³⁺ crystal into broadband radiation, including a wavelength of 762 nm, which causes the transition of oxygen molecules from the ground electronic state to the excited singlet state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

. The selection of the corresponding spectral range of radiation that causes the indicated transition can be carried out by the standard method using a monochromator or a separate diffraction reflective grating installed on the path of radiation emerging from the Al ₂ O ₃ Ti ³⁺ crystal and reflecting the spectrum allocated by the grating to the region of the combustion reaction between the outer surface of the flame tube 1 and the wall of the housing 2 of the combustion chamber. Multiple reflection of laser radiation between the mirrors 5, 16 forms a homogeneous, isotropic light field. A uniform light field provides an intensification of the effect of laser radiation on the processed air. The possibility of implementing such an optical scheme is confirmed by the research results (st .: N.I. Lipatov, A.S. Biryukov, E.S. Gulyamova. Light boiler-generator of singlet oxygen $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

// Quantum Electronics. 2008.V. 38. No. 13. C.1179-1182).

в воздухеFurther, as a result of relatively quick quenching of the state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

in the air

$$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}+M=O_2(a^{\mathrm{one}}{\Delta }_g)+M(\mathrm{one})$$

. Наличие активных центров-носителей цепного механизма окисления молекул СО в форме синглетного кислорода $$O_2(a^1{\Delta }_g)$$

позволяет интенсифицировать протекание цепной реакции окисленияa (1) metastable state occurs $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

. The presence of active carrier centers of the chain mechanism of oxidation of CO molecules in the form of singlet oxygen $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

allows to intensify the course of the oxidation chain reaction

$$CO+O_2(a^{\mathrm{one}}{\Delta }_g)=\mathrm{<figure-callout\; id="2"\; label="C\; O"\; filenames="00000014.png"\; state="\{\{state\}\}">C\; </figure-callout>}{O}_{}{}_2+O(2)$$

in the considered region of the combustion chamber, where, in addition to the oxygen atoms formed in the reaction of the chain mechanism (2), there are also active H atoms and OH radicals participating in the chain mechanism of CO oxidation. This allows to reduce the amount of carbon monoxide at the exit from the combustion chamber to the lowest possible level.

при воздействии лазерного излучения с длинной волны 1268 нм.A similar mechanism of oxidation of CO molecules is present in the case of excitation of O ₂ molecules in a singlet state $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

when exposed to laser radiation with a wavelength of 1268 nm.

и $$O_2(b^1{\displaystyle {\sum }_g^{+})}$$

.The method of operation of the combustion chamber of a gas turbine engine is as follows. Separately, fuel and air are supplied to the combustion chamber. In the working volume of the chamber, combustion and dilution zones are formed, while behind the front device of the flame tube 1, circulation flows 9 are formed, which are necessary to stabilize the flame. Fuel is sprayed into this zone through the fuel supply system 3 by a centrifugal nozzle. The air flow is divided into two parts. The primary air stream 12 is mixed with fuel and ignited in the cavity of the flame tube 1. Secondary air stream 13 is used to cool the walls of the flame tube 1. Laser radiation is applied to the primary and secondary air flows 12, 13 with the possibility of excitation of oxygen molecules to metastable singlet states. When laser radiation acts on the primary and secondary air streams 12, 13, a uniform, isotropic light field is formed, providing multiple reflection of laser radiation between the mirrors 16 in the input channel 15 of the primary air and the mirrors 5 located in the cavity 10 of the annular channel. Laser radiation provides excitation of molecular oxygen to singlet states $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

and $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

.

The impact on the stream 13 of secondary air is carried out by laser radiation in the cavity 10 of the annular channel, covering the combustion zone or dilution of the flame tube 1.

Simultaneously with the irradiation of the secondary air, the primary air is exposed to the laser radiation in the input channel 15, as shown in FIG. The specified effect causes in the stream 12 of primary air when it is mixed with fuel for a lean mixture ϕ <1: acceleration of combustion and preservation of thermodynamic parameters, including the speed of propagation of the flame (see figure 2) and the temperature of the combustion products (see figure 3), with a significant reduction in nitrogen oxides (about 1.87 times) compared with the traditional emission for a lean mixture without the use of laser exposure. From the graph shown in Fig. 2, it can be seen that the presence of singlet oxygen at a level of about 5% of the oxygen concentration in the ground electronic state allows burning without disruption for ϕ values of less than 0.66 (dashed line) while maintaining the laminar flame velocity of 15.5 cm / s and a decrease in the concentration of NO from 10.3 ppm to a value of 5.8 ppm, which is approximately 1.8 times less compared to conventional combustion (10.3 ppm), when there is no singlet oxygen in the combustion area. Near the indicated and considered points are given the values of the concentration of NO and speed U _n .

The proposed technical solution allows to increase the completeness of combustion of the air-fuel mixture and efficiency combustion chambers. The device of the gas turbine combustion chamber and the method of its operation make it possible to obtain an environmentally friendly exhaust of combustion products from a traditional combustion chamber, practically without nitrogen oxides and carbon oxides, which creates a significant technical and economic effect and can be implemented when creating aircraft gas turbine engines.

Claims (16)

1. The combustion chamber of a gas turbine engine, comprising a housing, a perforated flame tube in the housing with combustion and dilution zones, a fuel supply system, a primary and secondary air flow supply system, and an air-fuel mixture ignition device, an air flow supply system is provided with a device for influencing the primary flow air in the input channel of the primary air and a device for influencing the flow of secondary air in the cavity of the annular channel between the walls of the combustion chamber and the flame tube, from characterized in that the devices for influencing the flows of primary and secondary air contain a laser source, a laser divider for devices for influencing the flows of primary and secondary air, and each device is equipped with optical fibers with inputs connected to the laser divider, the output of the optical fiber of the device effects on the primary air flow is connected through a through hole to the input channel of the primary air, made with at least two arranged opposite each other mirrors, the device for influencing the flow of secondary air contains at least two opposite mirrors located in the cavity of the annular channel, where one of the mirrors has a through hole in the focal plane on the axis of symmetry, the output of the optical fiber of the device the secondary air flow is connected through a through hole of the mirror to the annular channel, and the laser radiation source is configured to excite oxygen molecules in the metasta yl singlet states. 2. The combustion chamber according to claim 1, characterized in that the source of radiation contains a laser, which is configured to excite molecular oxygen in a singlet state $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

. 3. The combustion chamber according to claim 1, characterized in that the radiation source comprises a laser, which is configured to provide excitation of molecular oxygen in a singlet state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

. 4. The combustion chamber according to one of claims 1 to 3, characterized in that the mirrors in the inlet channel of the primary air are made in the form of separate flat polyhedra. 5. The combustion chamber according to one of claims 1 to 3, characterized in that the mirrors are located in the cavity of the annular channel covering the combustion zone of the flame tube. 6. The combustion chamber according to one of claims 1 to 3, characterized in that the mirrors are located in the cavity of the annular channel covering the dilution zone of the flame tube. 7. The method of operation of the combustion chamber of a gas turbine engine, namely, that fuel and air are separately supplied to the combustion chamber, the air flow is divided into two parts, while acting on the primary air flow, mix it with fuel and ignite in the cavity of the flame tube, act to the secondary air stream and feed it through openings in the wall of the combustion tube combustion chamber, characterized in that the primary and secondary air flows are subjected to laser radiation with the possibility of exciting the molecule l of oxygen to metastable singlet states. 8. The method according to claim 7, characterized in that when exposed to laser radiation on the flows of primary and secondary air form a uniform, isotropic light field, providing multiple reflection of laser radiation between the mirrors. 9. The method according to PP.7 or 8, characterized in that the impact on the flows of primary and secondary air is carried out by laser radiation with the possibility of excitation of molecular oxygen in a singlet state $$O_2(a^{\mathrm{one}}{\Delta }_g)$$

. 10. The method according to PP.7 or 8, characterized in that the impact on the flows of primary and secondary air is carried out by laser radiation with the possibility of excitation of molecular oxygen in a singlet state $$O_2(b^{\mathrm{one}}{\displaystyle {\sum }_g^{+})}$$

. 11. The method according to PP.7 or 8, characterized in that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel covering the combustion zone of the flame tube. 12. The method according to claim 9, characterized in that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel covering the combustion zone of the flame tube. 13. The method according to claim 10, characterized in that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel covering the combustion zone of the flame tube. 14. The method according to PP.7 or 8, characterized in that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel covering the dilution zone of the flame tube. 15. The method according to claim 9, characterized in that the impact on the flow of secondary air is carried out by laser radiation in the cavity of the annular channel covering the dilution zone of the flame tube. 16. The method according to claim 10, characterized in that the impact on the stream of secondary air is carried out by laser radiation in the cavity of the annular channel covering the dilution zone of the flame tube.

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