RU2451878C1 - Method for preliminary preparation and combustion of "lean" air-fuel mixture in low-emission burner - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: invention relates to areas, where processes of mixing different liquids and gases take place, including processes of carburetion of various fuels with air and burning "lean" fuel-air mixture (FAM), in particular, to development of low-emission combustion chambers (LCC) of aircraft gas-turbine engines (GTE) and stationary gas-turbine plants (GTP) on the basis of low-emission burners (LB) with preliminary preparation and burning "lean" mixtures of fluid or gaseous fuels and air. The method for preliminary preparation and burning "lean" fuel-air mixture in a low-emission burner comprises an external bushing open at both ends, which comprises a supply fuel nozzle, a circular fuel receiver and dosing perforation arranged in the end of a fuel supply line, a permeable element with preset values of porosity and dispersity made of metal, and an axial-vane swirler with a central body of turbine type, arranged downstream the permeable element, in accordance with which fuel and air are previously mixed by supplying fuel into an air crossflow under excessive pressure via dosing perforation in order to reduce ways of mixing and increasing homogeneity of the mixture, further the flow of the formed "lean" fuel and air mixture is sent via the permeable element, where main mixing of components takes place to produce a homogeneous fuel and air mixture, then the flow is accelerated and swirled in order to form a circulation zone downstream a low-emission burner through sending the "lean" mixture flow via the axial-vane swirler. The fuel is divided into the main and the auxiliary ones, the central body is a central bushing that separates the low-emission burner into two coaxial circuits: inner and outer ones, besides, the outer circuit covers the inner circuit, the central bushing is arranged in the form of a sleeve so that it is open at the inlet and closed at the outlet, the central bushing is connected to the outer bushing with the help of hollow radial blades, each bushing (outer and central) comprises a circular fuel receiver, both bushings and radial blades comprise, moreover, dosing perforation arranged at the end of the main fuel supply line, cavities of the outer and central fuel receivers and cavities of radial blades form a single fuel cavity, the entire air is supplied only into the outer circuit under pressure, the main fuel is mixed previously with air by supplying the main fuel into the air crossflow under excessive pressure via dosing perforation arranged in bushings and blades, downstream the axial-blade swirler a hollow conical stabiliser is installed coaxially with it, representing a circular truncated cone, the top of which is sent against the flow, the front end of the stabiliser is closed, and its rear end is opened, downstream the stabiliser as a poorly streamlined body, an additional circulation zone is formed with substantially smaller dimensions compared to the main circulation zone, by means of supplying the "lean" fuel-air mixture to this stabiliser, the auxiliary fuel is supplied along the central bushing, further it is distributed in the form of a system of single jets, and is simultaneously accelerated by means of its passage via dosing perforation arranged in the end of the line of this fuel supply, and is then supplied under excessive pressure into an additional circulation zone of a stabiliser, where this fuel is mixed with the "lean" fuel-air mixture available in it.

EFFECT: invention makes it possible to increase efficiency of fuel and air mixing processes, reliability and operational life of burners, range of stable burning of lean FAM by air excess factor in case of lower pressure losses and emission of hazardous substances.

15 cl, 14 dwg

Description

The invention relates to the field of engineering, energy, transport and to other areas where there are processes of mixing various liquids and gases, including the processes of mixture formation of various fuels with air and combustion of a “poor” air-fuel mixture (FA), in particular to the creation of low-emission chambers combustion (ISS) of aircraft gas turbine engines (GTE) and stationary gas turbine units (GTU) based on low-emission burners (MG) with preliminary preparation and burning of “poor” mixtures of liquid or gaseous top rain and air.

The terms and concepts used below in the text to pneumatic spraying liquids and mixing liquids and gases are borrowed from [1] (Pazhi DG, Galustov BC Fundamentals of spraying liquids. - Moscow: Chemistry, 1984. 254 p.) , and the concepts relating to the combustion processes in the combustion chambers (CS) of a gas turbine engine are used from [2] (Lefebvre A. Processes in a gas turbine combustion chamber: Translated from English - Moscow: Mir, 1986, 566 pp.).

It is known [2] that the most important parameters on which the emission of nitrogen oxides (NO _x ) depends on the combustion of fuel assemblies in the combustion chamber (CS) of a gas turbine engine or gas turbine are the flame temperature and the residence time of the combustion products (PS) in the high temperature zone. These parameters, in turn, depend on the concentration of fuel in the air, i.e. on the coefficient of excess air in the combustion zone, and the time of formation of the reaction fuel assembly and its quality (concentration uniformity over the volume of the combustion zone), respectively.

During diffusion mixing of fuel and air, mixtures with very narrow concentration limits of ignition are formed. The “poor” (lower) and “rich” (upper) concentration limits of flame propagation depend on the type of fuel and correspond to the minimum flame temperature of the fuel in question. A fuel assembly of intermediate stoichiometric composition burns at a maximum temperature, which contributes to the formation of harmful nitrogen oxides. Combustion of fuel assemblies (i.e. flame propagation) is already unstable near the “poor” and “rich” limits. To significantly reduce the emission of nitrogen oxides, fuel assemblies should have a composition with a concentration significantly below the “poor” concentration limit. However, the “poor” fuel assembly of such a concentration composition is not able to burn without a stabilizing (“standby”) flame. In foreign literature, a stabilizing flame is called a pilot flame. The “depletion” of fuel assemblies is accompanied by an increase in its concentration inhomogeneity due to a decrease in the volumetric ratio of fuel to air and the appearance of local “enriched” and “depleted” zones, in which, due to the high combustion temperature of the “enriched” mixture, nitrogen oxide emission increases and occurs "Freezing" of carbon monoxide due to the low combustion temperature of the "depleted" mixture. With a significant “depletion” of fuel assemblies, obtaining a high-quality mixture of liquid fuel and air is much more difficult than a high-quality mixture of gaseous fuel and air, since at the same pressure the volume occupied by the liquid is hundreds of times smaller than the volume occupied by the gas. In addition, the splitting of liquid droplets occurs when the aerodynamic forces of the air exceed the surface tension of the liquid.

To reduce the emission of nitrogen oxides, they also strive to reduce the residence time of PS in the high temperature zone while maintaining the completeness of oxidation of the fuel. Mutual diffusion of fuel and air, the result of which is the formation of reactive fuel assemblies, is a slow process, which occupies a significant space of the fuel assembly combustion zone. Therefore, the process of preparing the “poor” fuel assemblies, limited by diffusion, is sought to be moved outside the combustion zone and carried out previously.

An equally important problem is the organization of stable combustion of the “poor” fuel assembly, the fuel concentration in which is below the “poor” concentration limit of flame propagation, as well as the elimination of the leakage of flame into the area of preliminary mixture preparation.

When creating burners, the problems mentioned above and some others need to be addressed simultaneously. However, in the known methods, these problems in the burners are solved either partially or insufficiently effectively. At the same time, attempts to solve them lead to a wide variety of methods for preliminary preparation and burning of the “poor” fuel assemblies and devices in which these methods are implemented.

Known methods for pre-mixing fuel and air in a burner or burner device. In this case, the fuel jets are fed into the satellite [3] (Japan Patent No. 2004 053048, 2002, F23R 3/18) and [4] (RF Patent No. 2099639, Bull. No. 35, 1997, F23R 3/28) or into the blowing air stream [5] (Japanese Patent No. 3174638, 2002, F23R 3/30). In accordance with other methods, the fuel jets are fed into a coaxial annular air stream preliminarily swirling using a blade swirl, covering the fuel supply device [6] (RF Patent No. 2094705, Bull. No. 30, 1997, F23R 3/16), [7] ( RF Patent No. 2137042, Bull. No. 25, 1999, F23R 3/16), [8] (RF Patent No. 2241177, Bull. No. 33, 2004, F23R 3/16) and [9] (RF Patent No. 2227247, 2001 , F23R 3/00). Two axial swirling air streams are also used with the help of scapular swirlers located in the same plane [10] (Japan Patent No. 2003194337, 2008, F23R 3/14) or displaced relative to each other in the flow [11] (RF Patent No. 2267710 , Bull. No. 1, 2006, F23R 3/20) and [12] (German Patent No. 4228816, 1998, F23R 3/14). Or the jets of fuel and air are pre-twisted in different directions using the corresponding blade swirls, and then mixed [13] (RF Patent No. 2083926, Bull. No. 19, 1997, F23R 3/16). The fuel assemblies obtained in this way in the first stage of the fuel assembly are additionally sequentially mixed with the annular air flow in the second stage previously swirled in the opposite direction using a radial blade swirler, then with the annular air flow in the third stage previously twisted in the opposite direction with the radial blade swirler [14] ( German patent No. 2442895, 1973, F23R 3/14). A method is also proposed [15] (British Patent No. 2179435, 1986, F23R 3/28), in accordance with which the fuel is fed into a coaxial air stream previously swirled with a blade swirler, the resulting mixture is additionally twisted using a blade swirler.

The advantage of these mixing methods is the fact that the use of scapular swirlers can improve the quality of the “poor” fuel assemblies by lengthening the mixing path during the movement of fuel and air during their mixing along the helix and the intensification of turbulent exchange under conditions of accelerated flow. The movement of the flow along the helix allows, in addition, to reduce the length of the burner and its mass.

A common drawback of all these considered methods of mixing using scapular swirlers, as shown by experimental studies of their gas-dynamic characteristics [16] (Shchukin VK, Khalatov AA Heat transfer, mass transfer and hydrodynamics of swirling flows in axisymmetric channels. - M.: Mechanical Engineering , 1982. 200 p.), There is a significant increase in pressure loss caused by the increased friction surface of the blades, lengthening of the mixing path and acceleration of flow with poor quality fuel assemblies.

The disadvantages of these jet methods of mixing fuel and air in burners from the point of view of improving the quality of the “poor” fuel assemblies are eliminated in the methods [17] (Japanese Patent No. 2000266316, 1999, F23D 11/40), [18] (Japanese Patent No. 3922115 B2, 2008 , F23R 3/42), [19] (US Patent No. 5,214,912, 1993, F23R 3/40) and [20] (RF Patent No. 2252065, Bull. No. 14, 2005, B01F 3/04, 5/06) by the use of permeable elements (PE). In accordance with these methods, a pre-prepared “poor” fuel assembly is additionally passed through PE, which provides a higher-quality fuel assembly due to an extensive system of microchannels and reduces the mixing of fuel and air as much as possible (up to the thickness of its material). The turbulent flow of fuel assemblies in the PE microchannels moves at low speeds, but sufficient for intensive mixing of fuel and air. Therefore, the pressure loss when mixing fuel and air in a burner using PE is less than in a burner using a blade swirler, where the turbulent flow of a fuel assembly moves at high speeds. In addition, PE, in contrast to the scapular swirler, has another positive property: due to its porous structure, it dampens pressure pulsations, preventing them from propagating upstream from the combustion zone of the mixture.

Stabilization of the combustion of the “poor” fuel assemblies in double-circuit burners, i.e. continuous supply of fresh fuel assemblies to the combustion zone is ensured by using an axial-blade swirl by organizing a vortex zone with the return flow of the “poor” fuel assemblies, the speed of which is less than the flame propagation velocity, and its reliable ignition and stable combustion using the “standby” torch [21 ] (RF Patent No. 2087805, Bull. No. 23, 1997, F23R 3/16), [22] (RF Patent No. 2107869, Bull. No. 9, 1998, F23R 3/00), [23] (RF Patent No. 2143642 , Bull. No. 36, 1998, F23R 3/34) and [24] (RF Patent No. 2170391, Bull. No. 19, 2001, F23R 3/14). However, such a method of stabilizing the combustion of a “poor” fuel assembly in a burner, as shown by experimental studies of axial-blade swirls [16], is accompanied by a significant increase in pressure loss in a free vortex outside the burner.

Pressure losses during stabilization of the combustion of a “poor” fuel assembly in a double-circuit burner with a “standby” torch can be significantly reduced if, instead of an axial-blade swirler, a hollow conical stabilizer with windows along the cone generators is used to organize a circulation zone with a return flow of a “poor” fuel assembly. This method of stabilizing the combustion of a “poor” fuel assembly is proposed in a Japanese patent [3].

To prevent flame penetration into the preliminary preparation area of the “poor” fuel assembly, the flow of this mixture is accelerated in a special narrowing device, which ensures the movement of the fuel assembly stream at a local speed exceeding the flame propagation velocity [4], [7], [13], [21] and [25] (US Patent No. 5285631, 1994, F02C 3/14). Such a constriction device installed at the outlet of the burner lengthens the burner and increases its mass, which is a disadvantage.

This disadvantage is eliminated in the methods using scapular swirlers installed at the end of the mixing path of the “poor” fuel assembly [5], [20]. Accelerating the flow of fuel assemblies in them not only improves the quality of the mixture, but also prevents the breakthrough of the flame without installing an additional narrowing device.

It should be noted that the use of PE [17] - [20] eliminates the breakthrough of the flame into the preliminary preparation area of the “poor” fuel assemblies due to the quenching of the flame in microchannels without accelerating the flow of the mixture with less loss of total pressure.

Closest to the proposed method for preliminary preparation and burning of the "poor" fuel assemblies in a dual-circuit low-emission burner is the method described in the patent [20]. The advantages and disadvantages of this method were mentioned above. In addition, it should be noted that a single-circuit burner provides a method for maintaining stable circulation movement of a fuel assembly stream and its stable combustion with a fuel concentration in the mixture not lower than the “poor” concentration limit. If fuel assemblies are “poorer” than this limit, then stable burning of such fuel assemblies is not provided in it, which is a disadvantage of the method.

The objectives of the invention, aimed at reducing the emission of nitrogen oxides in the COP GTE or GTU using MG, are:

- reduction of pressure losses in the preparation of “poor” fuel assemblies of increased uniformity;

- ensuring the combustion stability of the “poor” fuel assemblies with a fuel concentration below the “poor” concentration limit;

- reduction in the emission of nitrogen oxides;

- improving the reliability and service life of the burner and others.

The implementation of the tasks is ensured by the following technical solutions.

A method of preliminary preparation and burning of a “lean” air-fuel mixture in a low-emission burner, including an external sleeve open at both ends, which contains a fuel supply pipe, an annular fuel receiver and metering perforation made at the end of the fuel supply line, a permeable element with predetermined porosity and dispersion values, made of metal, and an axial-blade swirl with a turbine-type central body located behind the permeable element, in accordance with which air and air are pre-mixed by supplying fuel to a blowing air stream under excessive pressure through a metering perforation in order to reduce the mixing path and increase the homogeneity of the mixture, then the flow of the resulting “poor” air-fuel mixture is passed through a permeable element, where the main mixture of the components occurs to form a homogeneous air-fuel mixtures, then the flow is accelerated and twisted in order to form a circulation zone behind the low-emission burner by passing the flow of "poor" the mixture through an axial-blade swirl, while the fuel is divided into main and auxiliary, as a central body, a central bushing is used that separates the low-emission burner into two coaxial circuits: an external and an internal one, with the external circuit covering the internal circuit, the central sleeve is made in the form of a glass that it is open at the inlet and closed at the outlet, the central bushing is connected to the outer bushing using hollow radial blades, each bushing (external and central) contains an annular fuel the receiver, both bushings and the radial vanes contain, in addition, metering perforations made at the end of the main fuel supply line, the cavities of the external and central fuel receivers and the radial vanes cavity form a single fuel cavity, all air is supplied only to the external circuit under pressure, the main the fuel is pre-mixed with air by supplying the main fuel to a blowing air stream under excessive pressure through a metering perforation made in bushings and blades, for axial shovels with a full-time swirl set a hollow conical stabilizer coaxially with it, which is a circular truncated cone, the apex of which is directed against the flow, the front end of the stabilizer is closed, and its rear end is open, behind the stabilizer, as behind a poorly streamlined body, an additional circulation zone is formed that is much smaller than the main circulation zone, by supplying a flow of “lean” air-fuel mixture to this stabilizer, auxiliary fuel is fed through the central sleeve, then its distribution They are injected in the form of a system of single jets and simultaneously accelerated by passing it through a metering perforation made at the end of the fuel supply line, and then fed under excess pressure to the additional circulation zone of the stabilizer, where this fuel is mixed with the “poor” air-fuel mixture .

It is preferable that the auxiliary fuel consumption is controlled at all possible operating modes of the low-emission burner, regardless of the main fuel consumption, maintaining in the additional circulation zone behind the stabilizer a composition of the air-fuel mixture close to stoichiometric.

It is preferable that the maximum actual speed of movement of the “lean” air-fuel mixture at the entrance to the permeable element is provided no more than 40-60 m / s due to the appropriate choice of the surface area of the permeable element.

Preferably, behind the hollow conical stabilizer, a hollow cone is installed coaxially with it and at a certain axial distance from it with the apex directed against the flow so that between the inner surface of the stabilizer and the outer surface of the hollow cone a tapered annular gap tapering towards the outlet is connected to the flow part burners using a system of holes made in a conical stabilizer uniformly around the circumference, the cone contains a metering perforation made at the end of the auxiliary feed line of fossil fuels, the base of the cone being shifted against the flow relative to the base of the conical stabilizer so that the part of the internal conical surface of the stabilizer adjacent to its base and its rear end remain open, the “poor” air-fuel mixture is passed through the holes, then it is fed along the exit tapering a conical annular gap, and then in the form of a wall jet is fed along the open inner conical surface of the stabilizer under the action of a pressure differential arising between the proto part of the external contour of the burner and an additional circulation zone when the “lean” air-fuel mixture flows around the conical stabilizer.

It is preferable that the base of the hollow cone is displaced axially against the flow relative to the base of the conical stabilizer by a distance corresponding to a distance of not more than 15-20 gauges of the minimum width of the annular gap defined in the section perpendicular to the axis of the cone passing through the base of the hollow cone.

It is preferable that in the air flow in front of the permeable element between the outer and central bushings, a hollow annular shell is mounted, connected with them using hollow radial blades, the number of blades connecting the shell with the central bush is limited by the possibility of their placement on the central bush, the number of blades connecting the shell with an external sleeve, there may be more than the number of such pylons connecting the shell with the central sleeve, the internal cavity of the shell, the internal cavity of the radial lobes attacks and cavities of the central and external fuel receivers form a single fuel cavity, the shell divides the flow part of the external circuit into the peripheral and central, and the ratio of the air flow through the peripheral and central flow parts of the external circuit is approximately equal to the ratio of their perimeters, both bushings, blades and the shell has a metering perforation made at the end of the main fuel supply line, the main fuel and air are pre-mixed by supplying the main fuel under excess yes leniem in entraining air stream through the metering perforations bushings, blades and shroud.

Preferably, the contour of the shell and the contour of the radial blades in the corresponding perpendicular sections are in the form of an aerodynamically perfect symmetrical profile.

Preferably, the main fuel jets are fed at satellite angles to the blowing air stream.

Preferably, the tangential angles are in the range of 30 ° -60 °, and the relative pitch between the holes for supplying the main fuel should be at least 2.5-3.0.

It is preferable that either a system of truncated coaxial circular cones interconnected along respective circles be used as a permeable element so that in the longitudinal axial secant plane of the burner the permeable element forms a radial corrugation, the surface area of the permeable element for a given low emission burner geometry is changed by changing the corrugation pitch with the selected length of the generating cones and the angles between the generators or by changing the lengths of the generating cones and the angles between the generatrix by them at the selected corrugation step, or a system of radial plates mounted between the inner and outer bushings at an angle to each other and connected to each other along the radial ends of the plates so that the scan of the permeable element in the circumferential secant surface forms a corrugation, the surface area of the permeable element for a given the geometry of the low-emission burner is changed by changing the corrugation pitch for the selected plate width and the angle between them or by changing the plate width and the angle between them when corrugated step.

It is preferable that the diameters of the holes for supplying the main fuel vary in proportion to the change in the depth of the channel in which the air moves, if the ratio of the depth of the channel to the diameter of this hole is less than 20, otherwise the diameter of the holes for supplying the main fuel is kept the same regardless of the change in depth channel.

Preferably, liquid fuel is used as the main and auxiliary fuel.

Preferably, gaseous fuel is used as the primary and auxiliary fuel.

Preferably, liquid fuel is used as the main fuel, and gaseous fuel is used as the auxiliary fuel.

Preferably, gaseous fuel is used as the main fuel, and liquid fuel is used as the auxiliary fuel.

The method is illustrated by the following figures.

Figure 1. Scheme of radial corrugation of the surface of PE.

Figure 2. Scheme of circumferential corrugation of the surface of PE.

Figure 3. Scan of the surface of PE along the cross section A - A, indicated in the image of figure 2.

Figure 4. A longitudinal section of the MG of the first type along section AA, indicated in the image of FIG.

Figure 5. The front view of the MG of the first type along arrow A indicated in the image of Fig. 4.

6. View of the metering perforation 20 in the hollow cone 16 along arrow B shown in the image of FIG. 4.

7. View of the bypass holes 17 in the conical stabilizer 15 along arrow B shown in the image of figure 4.

Fig. 8. The symmetric profile of the hollow blade of the inlet scapula in section BB shown in the image of Fig. 4.

Fig.9. The scan of the axial-blade turbine type swirl in section BB, shown in the image of figure 4.

Figure 10. A longitudinal section of the MG of the second type along section AA, indicated in the image of FIG. 11.

11. The front view of the MG of the second type along arrow A indicated in the image of FIG. 10.

Fig. 12. The symmetric profile of the hollow shell in the section G-D indicated in the image of Fig.11.

Fig.13. A longitudinal section of the MG of the third type along the section A - A indicated in the image of Fig. 14.

Fig.14. The front view of the MG of the third type along arrow A indicated in the image of Fig. 13.

Here are the rationales for the technical solutions given above.

1. As already noted above, the method in the prototype allows for the preliminary preparation of high-quality “poor” fuel assemblies of increased uniformity with a fuel concentration not lower than the “poor” concentration limit, stabilization and stable combustion of this mixture. The increased homogeneity of the “poor” fuel assemblies is achieved through a two-stage mixture of fuel and air: jet mixing of fuel and air in the first stage and additional mixing of these components in an extensive system of PE microchannels in the second stage. The stability of combustion in a single-circuit MG from the prototype is ensured by the fact that with this composition of the fuel assembly, its reliable ignition and flame propagation occurs. The stabilization of fuel assembly combustion, i.e., the continuous supply of fresh fuel assemblies to the combustion zone, is achieved due to the circulation (vortex) zone created with the axial-blade swirl with a return flow of the mixture, the speed of which is less than the flame propagation velocity.

In the proposed method, in comparison with the prototype, the range of sustainable combustion is expanded to a mixture with a fuel concentration in them substantially lower than the “poor” concentration limit due to the creation of a “standby” torch in the MG by introducing two circuits: external and internal. The inner contour is formed by replacing the central body of the axial-blade swirl with a central sleeve closed at the outlet.

Fuel is divided into primary and secondary. All air and main fuel are supplied only to the external circuit, and auxiliary fuel is supplied only to the internal circuit to create a “standby” torch.

In the external circuit, the proposed method, as well as the prototype method, allows for preliminary preparation of high-quality “poor” fuel assemblies of increased uniformity due to two-stage mixing of the main fuel and air, however its composition is not limited by the “poor” concentration limit of flame propagation, but is much “poorer” ", And the formation of the main circulation zone using an axial-blade swirl.

If we organize a “standby” torch based on the main circulation zone, then the size of the emission of nitrogen oxides will correspond to the size of this zone. Note that in the “standby” flare, high-temperature combustion of reactive fuel assemblies is formed due to the “enrichment” of the “poor” fuel assemblies with auxiliary fuel in the circulation zone. The size of the emission of nitrogen oxides and the consumption of auxiliary fuel can be significantly reduced due to the volume of the circulation zone. For this purpose, a hollow circular conical stabilizer is installed behind the axial-blade swirl, coaxially with it, the apex of which is directed against the flow. Behind the stabilizer, as a poorly streamlined body [26] (Raushenbakh B.V. et al. Physical foundations of the working process in the combustion chambers of jet engines. - M.: Mashinostroenie, 1964. 466 pp.), By supplying a flow of "poor FAs to this stabilizer form an additional circulation zone, where the “standby” torch is localized. Since the diameter of the base of the conical stabilizer D _{CT is} much smaller than the inner diameter of the outer sleeve MG D _G , the size of the additional circulation zone is much smaller than the size of the main circulation zone [26].

The internal circuit in accordance with the proposed method allows to supply auxiliary fuel to the additional circulation zone in the form of a system of jets in order to reduce the mixing path and increase the homogeneity of the mixture, stable and stable combustion of the newly formed reactive fuel assemblies with lower emission of nitrogen oxides compared to the prototype. Ignition of this fuel assembly is provided from an external source.

In this case, the flamethrough is eliminated in the PE microchannels and additionally due to the acceleration of the flow of the “poor” fuel assemblies in the axial-blade swirl, which in this case, first of all, ensures the creation of a circulation zone.

2. The power plant can operate in a wide range of operating modes. When the power plant switches from the nominal operating mode to the low-gas mode, the composition of the fuel assembly is substantially “depleted”. However, the MG must ensure the stability of combustion of fuel assemblies of any composition. Therefore, it is proposed to regulate the auxiliary fuel consumption irrespective of the main fuel consumption, supporting the reactive composition of the fuel assemblies in any operating conditions of the power plant in the additional circulation zone. In order to have a supply of stable combustion during transient conditions with forced changes in the composition of fuel assemblies, it is more expedient to maintain the composition of fuel assemblies in the additional circulation zone close to stoichiometric.

3. Additional mixing of pre-prepared fuel assemblies in the PE microchannels is accompanied by pressure losses. The higher the flow rate of the mixture, the greater the pressure loss. Let us first consider the features of mixing liquid fuel and air using PE.

It is known that the density of a liquid is hundreds of times higher than the density of a gas, and the viscosity of a liquid is tens of times higher than the viscosity of a gas at the same temperature. With increasing temperature, the viscosity of the liquid decreases, and the viscosity of the gas increases, compensating for the difference in these viscosities at the initial temperature.

Qualitative mixing of liquid fuel and air is achieved by crushing liquid fuel with air into droplets as small as possible. Then the fuel droplets quickly evaporate and the combustion zone of the fuel assembly is reduced.

The use of PE allows not only to significantly reduce the initial droplets of liquid fuel, but also to calibrate them by size due to the regular structure of micropores of PE. The degree of grinding of the initial droplet will depend on the size of the pores and particles forming PE, the porosity of the PE material, air density and the ratio of air flow to liquid fuel consumption in the mode of crushing liquid fuel droplets.

Experimental studies of the regimes of crushing liquid droplets by a gas stream showed [27] (Kutysh DI Candidate dissertation. Moscow. MAI, 2004. 215 pp.) That in the regime of crushing liquid droplets using PE, the maximum actual velocity of the mixture is ~ 85-87 m / s is achieved when the ratio of gas flow to liquid flow is equal to 3. With an increase in this ratio, the required speed of the mixture, necessary for crushing drops of liquid, decreases. So, with the value of this ratio equal to ~ 12, the required speed of the mixture is ~ 70 m / s.

Under the conditions of a gas turbine engine, the ratio of air to liquid fuel consumption, even for stoichiometric fuel assemblies, is about 15-17. If you burn the “poor” fuel assemblies, the value of this ratio increases significantly in accordance with the value of the coefficient of excess air. Consequently, the required speed of the fuel assembly movement drops significantly, which reduces the pressure loss in the PE. However, with the increase in the surface area of PE, due to a decrease in the required speed of movement of fuel assemblies in it, the space occupied by PE and the weight of the burner increase.

Based on the known experimental data [27], the optimal speed of fuel assemblies at the PE inlet, sufficient for crushing liquid fuel and not causing significant pressure losses, can be assumed in the range of 40-60 m / s.

The density and viscosity of gaseous fuels does not differ so much from the density and viscosity of air as the density and viscosity of liquid fuels. Moreover, with increasing temperature, their viscosities simultaneously increase without changing the mixing conditions of these components. Therefore, it is much easier to mix gaseous fuel and air with quality than liquid fuel and air.

At low subsonic speeds, laws describing the motion of a fluid remain valid for studying gas motions. Therefore, the optimal speed of the fuel assembly at the entrance to the PE, justified for the case of mixing liquid fuel and air, remains valid for mixing gaseous fuel and air.

4. The resource of the COP determine its most heat-stressed elements, which include MG. Preliminary experimental studies of the characteristics of the MG, in which the proposed method is implemented, showed that an unacceptable heating of the output edge of the conical stabilizer occurs due to radiant heat fluxes from the “standby” torch. When a poor fuel assembly flows around the outer surface of a conical stabilizer, it partially cools. However, it is not sufficient for the temperature of the material of the conical stabilizer to be lower than the permissible value. Such heating of the output edge of the conical stabilizer reduces the life of the MG and CS as a whole. Avoid unacceptable heating of the output edge of the stabilizer can be due to protective cooling of this edge also from the inside of the stabilizer. To ensure the reliability and service life of the conical stabilizer and the burner as a whole, a wall cooling jet is proposed to be arranged using a hollow cone with an apex against the flow, installed behind the conical stabilizer coaxially with it and at a certain axial distance from it so that a conical ring gap tapering towards the exit is formed . The base of the hollow cone is offset against the flow relative to the base of the conical stabilizer. The displacement is necessary so that a parietal obstruction jet arises relative to the cold “poor” fuel assembly.

The parietal jet is obtained by supplying a “poor” fuel assembly from the MG flow passage through the bypass holes made uniformly around the circumference in the stabilizer, then along the conical annular gap under the influence of the pressure drop that arises between the MG flow passage and the stabilizer’s internal cavity when it flows around its “poor” fuel assembly . The conical annular gap must be tapering towards the exit, so that the maximum velocity of the wall jet is established in the exit section of the gap.

5. It is known from experimental data on the study of plane jets in a carrying flow [28] (Kutysh II Numerical methods for solving environmental problems. M: Inform-Knowledge, 2002. 362 pp.) That the range of such a jet depends on angle of its expiration. The smaller the angle of the jet, the greater its range and the more stable the jet. The parietal stream has maximum range and stability. It follows from the experimental data that the organized movement of the flow of “poor” fuel assemblies along the inner surface of the stabilizer is maintained at a length of the order of 15–20 calibres of the minimum width of the annular gap.

If the displacement of the bases of the conical stabilizer and the hollow cone is too large, the near-wall jet of the “poor” fuel assembly moving along the internal conical surface of the stabilizer will erode before it reaches its base, which can lead to overheating of the output end of the stabilizer. If the displacement of the bases of the conical stabilizer and the hollow cone is too small, then not only the end of the stabilizer, but also the end of the hollow cone will be exposed to high temperatures.

To obtain a stable near-wall jet and to prevent overheating of the output end of the conical stabilizer, as the experimental data show, the base of the hollow cone should be displaced axially against the flow relative to the base of the conical stabilizer by a distance corresponding to a distance of not more than 15-20 calibres of the minimum width of the annular gap, defined in the section perpendicular to the axis of the cone, passing through the base of the hollow cone, or at a shorter distance to guarantee stability wall jet.

6. If the central sleeve has a small diameter, then when designing the MG with preliminary preparation of the “poor” FA, it becomes difficult to place hollow blades on this sleeve, through the metering perforation of which the main fuel is fed into the blowing air stream. This problem can be solved by placing a hollow annular shell in front of the PE, which also has a metering perforation for distributing the main fuel into separate jets. The shell divides the flow part of the outer contour of the MG into peripheral and central. Moreover, the ratio of air flow through the peripheral and central flow parts of the external circuit is approximately equal to the ratio of their perimeters. Since dosing perforation is located on the surface of the MG flowing part, it is advisable to take the perimeter of the flowing part as a parameter by which the air flow is distributed.

The shell allows you to supply fuel from an external receiver to the central receiver using hollow blades, the number of which in the peripheral flow part and in the central flow part of the MG can be selected arbitrarily independently of each other. That is, the number of blades in the central flow part can be taken less so that they can be placed on the surface of the central sleeve, and in the peripheral flow part the number of blades can be significantly larger.

7. Profile pressure loss due to the occurrence of a boundary layer on the surface of the shell and blades [29] (Stepanov G.Yu. Hydrodynamics of the lattices of turbomachines. - M .: Fizmatgiz, 1962. 512 s.), It is possible to reduce if the contours of the shell and blades are performed in the form of an aerodynamically perfect symmetrical profile with minimal profile losses. Such a symmetrical profile can be constructed in accordance with the methodology given in [30] (Salamatin NE, Izvestiya Vuzov Aviation Engineering, No. 1, 1969.).

8. Experimental studies of the laws of single-row systems of jets in a blowing air stream indicate that the pressure loss on mixing jets and a blowing stream when blowing jets at satellite (sharp) angles to the blowing stream is less than when blowing jets at right angles or at opposite angles [28 ]. Moreover, the smaller the angle, the lower the loss of mixing. Guided by these experimental data, it is customary to blow the jets of the main fuel at tangled angles to the blowing air stream.

9. To make holes at very sharp angles to the underlying surface in practice is associated with significant problems. At the same time, experimental data show [28] that, starting from an acute angle of 60 °, the mixing pressure loss is significantly reduced compared to the mixing pressure loss when blowing jets at right or opposite angles. To make holes at an angle of less than 30 ° is impractical from the point of view of mixing pressure loss. Based on the known experimental data [28] and the above arguments, a range of angles of 30 ° –60 ° is recommended, under which it is advisable to make holes in the MG to supply the main fuel.

In addition, the theoretical calculations performed by the authors on the basis of the equations of conservation of energy, momenta and consumption of the main fuel and air showed that the pressure in the stream after mixing the components when blowing fuel jets at angles of 30 ° -60 ° even increases slightly, since the energy introduced fuel when feeding it into a blowing air stream under some excess pressure exceeds the energy loss of the air stream from mixing it with fuel.

In order not to pre-merge a single-row system of fuel jets into a continuous shroud with a simultaneous increase in its penetration depth into the drift flow and range, the relative step between the holes should be more than 2.5-3.0. The jets of a single-row system with such a relative pitch, as shown by experimental data [28], behave as single ones and mix faster with a drift flow than a continuous shroud.

10. In order to be able to establish the flow rate of the “poor” fuel assemblies necessary for crushing liquid fuel at the PE inlet, the only parameter that can be controlled with a given MG geometry is the surface area of the PE. Figure 1-figure 3 shows the possible schemes in accordance with which can be made PE, where

l _i - the length of the i-th generatrix of the circular cone;

α _i is the angle between the i-th generators of the cones;

b _i is the width of the i-th permeable plate;

φ _i is the angle between the i-permeable plates;

s is the corrugation pitch.

Figure 1 shows a diagram of the radial corrugation of the surface of the PE, and figure 2 is a diagram of the circumferential corrugation of the surface of the PE.

In accordance with the scheme (figure 1) to control the surface area of the PE and the flow rate of the "poor" fuel assemblies at the entrance to the PE can be as follows. By changing the corrugation step (the number of corrugations at a given radius) for a given length of the generatrix of the circular cones and the angle between them, or by changing the length of the generatrix of the circular cones and the angles between them at a given step of the corrugation.

In accordance with the scheme (figure 2 and figure 3) to control the surface area of the PE and the flow rate of the "poor" FA at the entrance to the PE can be as follows. By changing the corrugation step (the number of corrugations at a given length of the section) at the selected plate width and the angle between them, or by changing the width of the plates and the angles between them at the selected corrugation step.

, где Н - действительная глубина канала, d - диаметр отверстия для подачи топлива, по радиусу МГ может изменяться в несколько раз.11. The number of blades in the inlet vanes of the MG can be selected sufficiently large. In this case, the relative depth of the interscapular canal

where H is the actual depth of the channel, d is the diameter of the hole for supplying fuel, along the radius of the MG can vary several times.

The influence of the relative dimensions of the channel on the characteristics of the systems of fuel jets is usually estimated by the magnitude of the change in the depth of penetration of the jet and their range and the magnitude of the acceleration of the blowing air flow caused by clutter of the channel with fuel jets.

происходит радикальная перестройка течения в области взаимодействия систем струй топлива и сносящего воздушного потока, заключающаяся в том, что значительно уменьшаются глубина проникновения струй и их дальнобойность и также существенно ускоряется сносящий поток. Причем положение глубины проникновения струй смещается вверх по потоку, а положение максимальной относительной скорости потока - вниз по потоку.In [31] (Kutysh II, Kutysh DI On the issue of preliminary preparation of the air-fuel mixture during the conversion of hydrocarbon fuel for low-emission gas turbines // Conversion in mechanical engineering. 2003, No. 6. P.55-67.) It was established in channels with relative depth

there is a radical restructuring of the flow in the field of interaction between the systems of fuel jets and the blowing air stream, which consists in the fact that the depth of penetration of the jets and their range are significantly reduced and the drift flow is also significantly accelerated. Moreover, the position of the depth of penetration of the jets is shifted upstream, and the position of the maximum relative velocity of the stream is downstream.

практически сохраняются не только значения этих параметров струй, но и положения их максимальных значений вдоль траектории струи. Поэтому для всех значений гидродинамического параметра начиная со значения

системы струй можно считать полуограниченными, так как изменение глубины проникновения струи и ускорение сносящего потока составляют ~2% или меньше.In channels with

practically not only the values of these parameters of the jets are preserved, but also the positions of their maximum values along the path of the jet. Therefore, for all values of the hydrodynamic parameter, starting from the value

jet systems can be considered semi-limited, since the change in the depth of penetration of the jet and the acceleration of the drift flow are ~ 2% or less.

We establish the law of changing the diameter of the fuel supply hole when changing the channel depth for the case when

When blowing jets of fuel from opposite walls of the channel so that the jets do not interact with each other at any depth of the channel, but only with a blowing air stream, we take

where y _max is the depth of penetration of the fuel jet into the drift stream, i.e. the distance corresponding to the most remote point of the jet path from the underlying surface;

C ₂ is a constant value, which for any channel depth should be C ₂ <0.5.

Since the outflow of the jets comes from a common receiver at the same pressure, the value of the hydrodynamic parameter and the relative depth of penetration of the jet of any diameter is a constant value, i.e.

where q _V is the hydrodynamic parameter;

ρ _V and ρ _W are the density of the jet of fuel and air, respectively;

V and W are the speed of the jet of fuel and air, respectively.

The value of the constant C _{1 is} determined from the conditions of the expiration of the jet at the periphery of the flow part:

where the index "P" refers to the parameters on the periphery of the flow part of the burner.

Then from (1), taking into account relations (2) and (3), the law of changing the diameter of the hole for supplying fuel along the relative depth of the channel

or

which is formulated as follows: the diameters of the holes for supplying the main fuel vary in proportion to the change in the depth of the channel in which the air moves.

12. Using the last four technical solutions, the possible combinations of the use of liquid and gaseous fuels in the MG during the preparation of the “poor” FAs and its stable combustion in the ISS GTE and stationary gas turbines are shown.

MG of various types, in which the proposed method for preliminary preparation and burning of the “poor” fuel assemblies is implemented, are shown in the figures (Fig. 4-Fig. 14).

The MG of the first type, shown in Fig.4-Fig.9, contains a fuel supply pipe 21, an outer sleeve 11 (not necessarily cylindrical) open at both ends, including an external fuel receiver 2 and a metering perforation 4, made at the end of the main fuel supply line 1, open at the inlet and closed at the exit of the Central sleeve 12, mounted coaxially with the external sleeve and includes a Central fuel receiver 3 and metering perforation 4, made at the end of the main fuel supply 1, hollow radial blades 14, connected external and central bushings and their receivers, PE 10, installed between the outer and central bushings behind the inlet vanes, axial-blade swirl 13, installed between the outer and central bushings behind the PE, hollow circular conical stabilizer 15, mounted behind the axial-blade swirl coaxial with the apex against the flow, a hollow circular cone 16, including a metering perforation 20, made at the end of the auxiliary fuel supply line 7, and mounted at some axial distance about of the conical stabilizer with an anti-flow tip so that between the inner surface of the conical stabilizer and the outer surface of the cone an annular conical gap 19 narrowing towards the exit is formed. The base of the hollow cone 16 is displaced against the flow relative to the base of the conical stabilizer by a distance L so that a part of the inner surface of the conical stabilizer is adjacent to its base, and its posterior end remain open. The distance L corresponds to a distance that does not exceed 15-20 gauges of the width of the slit, measured in a section perpendicular to the axis passing through the base of the hollow cone.

In view A (Fig. 5), an input blade apparatus is shown, as well as an example of the arrangement of radial blades 14 in it and an example of metering perforation 4 for supplying the main fuel 1 in the bushings 11 and 12, respectively, and in the blades 14. On a local section of type A ( 5) it is shown that the cavity of the hollow blades 14 and the cavity of the outer and central fuel receivers 2 and 3, respectively, form a single fuel cavity.

On the form B (Fig.6) shows an example of the implementation of the metering perforation 20 in the hollow cone 16, and on the form B (Fig.7) - an example of the bypass holes 17 in the conical stabilizer 15.

Section BB (Fig. 8) shows a symmetrical profile of a hollow blade made in accordance with the methodology of [30]. Also shown are the openings of the metering perforation 4 for supplying the main fuel 1, made at an acute angle α to the underlying surface. Angle α is in the range of 30 ° ≤α≤60 °.

In section BB (Fig. 9), a scan of an axial-blade turbine type swirl is shown.

PE 10 can be made with radial corrugation of its surface in accordance with the scheme shown in figure 1, or with circumferential corrugation of its surface in accordance with the scheme shown in figure 2. and figure 3.

The MG of the second type shown in FIG. 10-FIG. 12 differs from the MG of the first type shown in FIG. 4-FIG. 9 as follows.

Before PE in the air flow, a hollow annular shell 22 is installed, containing the metering perforation 4, made at the end of the main fuel supply line 1 (Fig. 12).

In a view A (Fig. 11), a shell 22 and its connection with polly blades 14 are shown, and a local section shows an example of the location of the holes of the metering perforation 4 on the shell and on the hollow blades 14. The shell cavity, the cavity of the blades and the cavity of the fuel receivers (external and central) form a single fuel cavity. The shell divides the flowing part of the external circuit into the peripheral and central parts. Moreover, it divides the air flow between the peripheral and central flowing parts in proportion to the perimeter occupied by these flowing parts. Essentially, this means that the number of perforation holes is proportional to air flow.

In section G-D (Fig. 12), a symmetrical profile of a hollow shell is shown, made in accordance with the methodology of [30]. Also shown are the openings of the metering perforation 4 for supplying the main fuel 1, made at an acute angle α to the underlying surface. The angle α is also in the range of 30 ° ≤α≤60 °.

In this example, the execution of the MG of the second type (Fig.10-Fig.12) taken the minimum number of radial hollow blades, so the shell is hollow and has a metering perforation.

The MG of the third type shown in FIG. 13 and FIG. 14 differs from the MG of the second type shown in FIG. 10-FIG. 12 only in the number of radial hollow blades in the inlet vanes. Moreover, the number of hollow blades located in the peripheral flow part of the outer contour of the MG is twice as large as the radial hollow blades located in the central flow part of the outer contour of the device. However, the number of blades in the peripheral flow part of the outer contour of the MG can be any, not connected in any way with the number of blades located in the central flow part, where their number is limited by the possibility of location on the central sleeve.

With a large number of hollow blades of the inlet scapula located in the peripheral flow part of the outer contour of the MG, the shell can be solid. In this case, the hollow blades of the peripheral flow part and the central flow part of the external circuit should be located on the same radius, communicate with each other and have a single fuel cavity. At the same time, the diameter of the perforation hole along the radius of the hollow blade should be changed according to the law described in paragraph 11, if the relative depth of the interscapular canal

Implementation of the proposed method in the MG of various types (Fig.4-Fig.14) is as follows.

Air under pressure enters the external circuit MG. The main fuel 1 through the inlet pipe 21 first enters the external fuel receiver 2, then through the hollow blades 14 it is supplied either to the central fuel receiver 3 (see Fig. 4 and Fig. 5), or to the annular shell 22 and to the central fuel receiver 3 if the MG contains an annular shell 22 (Fig.10, Fig.11 and Fig.13, Fig.14). The main fuel 1 enters the blowing air stream under excessive pressure in the form of jets through the metering perforation 4, made in the outer and central bushings 11 and 12, respectively, in the annular shell 22 and in the blades 14, at tangential angles to the blowing air stream 6. As a result the jet mixing of the main fuel 1 with air 6 in the first stage of the MG forms a “poor” fuel assembly 5, which does not have sufficient concentration uniformity. Therefore, the main fuel and air are additionally mixed in the second stage by passing the “poor” fuel assembly 5 through PE 10, where the formation of high-quality (uniform) fuel assembly.

Then, the main circulation zone 8 is formed by passing the “poor” fuel assembly 5 through the turbine axial-blade swirl 13 and the additional circulation zone 9 of substantially smaller size by feeding the “poor” fuel assembly 5 to the conical stabilizer 15 in the same way as for a poorly streamlined body.

Part of the “poor” fuel assembly 5 passes through the bypass holes 17 and the conical annular gap 19, where it moves with acceleration under the influence of the pressure differential that arises between the flow part of the outer contour of the MG and the additional circulation zone when the “poor” air-fuel mixture flows around the conical stabilizer. Further, this part of the “poor” fuel assembly moves in the form of a wall jet 18 along the inner surface of the conical stabilizer 15, protecting it from the effects of radiant fluxes of the “standby” torch.

Auxiliary fuel 7 is fed through a fuel line located in the Central sleeve 12, then it is simultaneously accelerated and distributed in the form of a system of jets by passing through a metering perforation 20, made at the end of the auxiliary fuel supply line 7, and then fed under excess pressure to the additional circulation zone 9, where it mixes with the “poor” fuel assembly 5, enriching it to a composition close to stoichiometric, by regulating the supply of auxiliary fuel 7.

Ignition of fuel assemblies located in the additional circulation zone 9 is carried out from an external source.

You can note the following advantages of the proposed method implemented in the MG of various types (Fig.4-Fig.14), compared with the prototype method:

- reliable ignition of the “poor” fuel assembly, the composition of which is below the “poor” concentration limit of flame propagation;

- reduced emission of nitrogen oxides;

- reduced auxiliary fuel consumption;

- reduced pressure loss;

- increased service life of MG, etc.

These advantages are achieved through the use of the “on-duty” torch, the organization of an additional circulation zone substantially smaller than the dimensions of the main circulation zone, the supply of primary fuel at satellite angles to the blowing air stream, and maintaining at a nominal MG operating mode a low flow rate of the “poor” fuel assembly at the inlet in PE, but sufficient for crushing droplets of liquid fuel, the introduction of dual barrier cooling of the surface of a conical stabilizer and other technical solutions, a decree nnyh above.

Claims (15)

1. A method for preliminary preparation and burning of a “lean” air-fuel mixture in a low-emission burner, including an external sleeve open from both ends, which contains a fuel supply pipe, an annular fuel receiver and a metering perforation made at the end of the fuel supply line, a permeable element with predetermined porosity and dispersion made of metal, and an axial-blade swirl with a turbine-type central body located behind the permeable element, in accordance with which fuel and air are pre-mixed by supplying fuel to a blowing air stream under excessive pressure through a metering perforation, in order to reduce the mixing path and increase the homogeneity of the mixture, then the flow of the resulting “poor” air-fuel mixture is passed through a permeable element, where the main mixture of components is formed to form a homogeneous air-fuel mixture, then the flow is accelerated and twisted, in order to form a circulation zone behind the low-emission burner by passing the flow of “poor »The mixture through an axial-blade swirl, characterized in that the fuel is divided into main and auxiliary, as the central body, use a central sleeve that separates the low-emission burner into two coaxial circuits: external and internal, with the external circuit covering the internal circuit, the central sleeve is made in in the form of a glass so that it is open at the inlet and closed at the outlet, the central sleeve is connected to the external sleeve using hollow radial blades, each sleeve (external and central) contains The ring fuel receiver, both bushings and radial blades contain, in addition, metering perforations made at the end of the main fuel supply line, the cavities of the external and central fuel receivers and the radial blade cavities form a single fuel cavity, all air is supplied only to the external circuit under pressure, the main fuel is pre-mixed with air by supplying the main fuel to a blowing air stream under excessive pressure through metering perforations made in bushings and blades, for a a hollow conical stabilizer is installed coaxially with the axial-blade swirl, which is a circular truncated cone, the apex of which is directed against the flow, the front end of the stabilizer is closed, and its rear end is open, behind the stabilizer, as behind a poorly streamlined body, an additional circulation zone of significantly smaller sizes is formed than the main circulation zone, by supplying a flow of “lean” air-fuel mixture to this stabilizer, auxiliary fuel is fed through the central sleeve, then it is distributed in the form of a system of single jets and at the same time accelerated by passing it through a metering perforation made at the end of the supply line of this fuel, and then fed under excess pressure to the additional circulation zone of the stabilizer, where this fuel is mixed with the “poor” air-fuel in it a mixture. 2. The method according to claim 1, characterized in that the auxiliary fuel consumption is regulated at all possible operating modes of the low-emission burner, regardless of the main fuel consumption, maintaining in the additional circulation zone behind the stabilizer a composition of the air-fuel mixture close to stoichiometric. 3. The method according to claim 2, characterized in that the maximum actual speed of the movement of the "poor" air-fuel mixture at the entrance to the permeable element is provided no more than 40-60 m / s due to the appropriate selection of the surface area of the permeable element. 4. The method according to claim 3, characterized in that behind the hollow conical stabilizer, a hollow cone is installed coaxially with it and at a certain axial distance from it with the apex directed against the flow, so that a narrowing is formed between the inner surface of the stabilizer and the outer surface of the hollow cone to the exit there is a conical annular gap connected to the flow part of the burner by means of a system of holes made uniformly around the circumference of the conical stabilizer, the cone contains a metering perforation made at the end of the master whether the auxiliary fuel supply, and the base of the cone is offset against the flow relative to the base of the conical stabilizer so that the part of the inner conical surface of the stabilizer adjacent to its base and its rear end remain open, the “poor” air-fuel mixture is passed through the holes, then it is fed in to the exit of the conical annular gap, and then in the form of a wall jet, they are fed along the open inner conical surface of the stabilizer under the influence of a pressure differential, it between the flow part of the outer contour of the burner and an additional circulation zone at a flow conical stabilizer "lean" air-fuel mixture. 5. The method according to claim 4, characterized in that the base of the hollow cone is displaced axially against the flow relative to the base of the conical stabilizer by a distance corresponding to a distance of not more than 15-20 gauges of the minimum width of the annular gap, defined in the section perpendicular to the axis of the cone, passing through the base of the hollow cone. 6. The method according to claim 5, characterized in that in the air stream in front of the permeable element between the outer and Central bushings set a hollow annular shell connected to them using hollow radial blades, the number of blades connecting the shell with the Central sleeve is limited by the possibility of their placement on the central sleeve, the number of blades connecting the shell to the outer sleeve may be greater than the number of such pylons connecting the shell to the central sleeve, the inner cavity of the shell, the internal cavities radial blades and cavities of the central and external fuel receivers form a single fuel cavity, the shell divides the flow part of the external circuit into the peripheral and central, and the ratio of air flow through the peripheral and central flow parts of the external circuit is approximately equal to the ratio of their perimeters, both bushings, blades and the shell have a metering perforation made at the end of the main fuel supply line, the main fuel and air are pre-mixed by supplying the main fuel d overpressure in entraining air stream through the metering perforations bushings, blades and shroud. 7. The method according to claim 6, characterized in that the contour of the shell and the contour of the radial blades in the corresponding perpendicular sections are performed in the form of an aerodynamically perfect symmetrical profile. 8. The method according to claim 5 or 7, characterized in that the jet of main fuel is fed at satellite angles to the blowing air stream. 9. The method according to claim 8, characterized in that the tangled angles are in the range of 30-60 °, and the relative step between the holes for supplying the main fuel should be at least 2.5-3.0. 10. The method according to claim 9, characterized in that as a permeable element, either a system of truncated coaxial circular cones connected to each other along respective circles is used so that in the longitudinal axial secant plane of the burner, the permeable element forms a radial corrugation, the surface area of the permeable element for the predetermined geometry of the low-emission burner is changed by changing the corrugation pitch at the selected length of the generating cones and the angles between the generators or by changing the lengths of the generating cones and the angle in between the generators at the selected corrugation step, or a system of radial plates installed between the inner and outer bushings at an angle to each other and connected to each other along the radial ends of the plates so that the scan of the permeable element in the circumferential secant surface forms a corrugation, the surface area of the permeable element for a given geometry, a low-emission burner is changed by changing the corrugation pitch for the selected plate width and angle between them or by changing the plate width and angle m between them at the selected corrugation step. 11. The method according to claim 10, characterized in that the diameters of the holes for supplying the main fuel are changed in proportion to the change in the depth of the channel in which the air moves, if the ratio of the depth of the channel to the diameter of this hole is less than 20, otherwise the diameter of the holes for supplying the main fuel keep the same regardless of changes in channel depth. 12. The method according to claim 11, characterized in that liquid fuel is used as the main and auxiliary fuel. 13. The method according to claim 11, characterized in that gaseous fuel is used as the main and auxiliary fuel. 14. The method according to claim 11, characterized in that liquid fuel is used as the main fuel, and gaseous fuel is used as auxiliary fuel. 15. The method according to claim 11, characterized in that gaseous fuel is used as the main fuel, and liquid fuel is used as auxiliary fuel.

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