UA98097C2 - Multi-channel tubular type burner of a gas-turbine engine with injector gas supply - Google Patents

Abstract

A multi-channel tubular type burner of a gas-turbine engine with injector gas supply comprises a central section and peripheral section that are separated two-chamber fuel systems that are formed withby tube plates, air tubes with respective diameters and side plates of cylindrical type, from those fuel gas independently comes to zones of kinetic and diffuse mixture formation.

Description

The invention relates to combustion chambers of gas turbine engines operating as part of gas pumping units and power plants on compressed natural gas without injection of water or steam into the combustion chamber.

A gas turbine combustion chamber design with low emission of harmful substances is known

IPat. of the Russian Federation Mo 2111416, IPC R23ZK 3/34, registered on 05/20/1998), containing at least one heat pipe consisting of a pre-chamber and a main combustion chamber with a nozzle and cavities for fuel gas supply and gas-air mixing. The inner walls of the antechamber are made with a constant cross-section, the outer walls form an annular gap with the inner walls. In the expanding part of the nozzle, holes are made for the exit of the mixture of fuel gas and air into the inner cavity of the main chamber. In addition, the body of the main chamber has a second row of additional holes connecting the same cavities, which is located concentrically to the main row.

The disadvantages of this design are the lack of diffusion mixing of fuel gas and air, which leads to complications of the combustion process and operation, a negative effect on the reliability of the engine.

In addition, the supply of a lean fuel-air mixture through separate holes in the main chamber does not ensure uniformity of temperature in the combustion zone, which leads to an increase in MOx and CO emissions.

There is a design of the combustion chamber (Pat. of the Russian Federation Me2098719, IPC G2ZK 3/34, registered on 10.12.1997), which has a heat pipe consisting of a preliminary mixing chamber, a nozzle and a main combustion chamber. The narrowing nozzle is placed inside the previous chamber with the formation of an inner mixing chamber, which also narrows, and an outer mixing chamber, which narrows and then expands, at the entrance of which slotted tangential air supply channels are made, and in the walls of the channels, supply holes are made fuel gas, while the axes of these channels are located in front of the transverse inlet section of the slit channel perpendicular to its walls.

The disadvantages of such a combustion chamber are the low efficiency of the fuel gas supply at the entrance to the slotted tangential channels, which can lead to the exit of part of the gas from the mixing zone and its entry into the cooling system of the heat pipe with its subsequent removal from the zone

From burning. In addition, the presence of diffusion mixture formation and low-quality combustion leads to an increase in the formation of MOx and complicates the combustion chamber control algorithm. Penetration of the zone of backflows of combustion products along the axis of the heat pipe into the internal mixing chamber leads to the leaping of the flame into the internal mixing chamber and, in connection with this, an increase in the MOH level and overheating of the nozzle, which negatively affects the reliability and durability of the combustion chamber design .

The combustion chamber of a gas turbine of a power plant is known (Patent of Ukraine for an invention No. 68446, IPC (2006) R2Z3K 3/34, registered on 16.08.2004, Bull. 8), which has a heat pipe consisting of a concentrically located central part and a peripheral part with internal and external mixing chambers, at the entrance of which air supply channels are made, and the main combustion chamber, while the external mixing chamber is made continuously narrower, in the internal mixing chamber along its horizontal axis there is a squeezer for return flows of combustion products with a number of holes in the end wall for cooling air, at the outlet of the inner mixing chamber in front of the main combustion chamber there is a preliminary combustion chamber, which has an inner casing and an outer casing with holes for cooling air. In addition, the air supply channels are made in the form of radial blade swirlers, in each blade of which there are fuel gas supply channels with outlet openings directed into the inter-blade channels, while the axes of the outlet openings are perpendicular to the walls of the blades.

This construction is taken as the closest analogue. The combustion process in this burner system has a disadvantage associated with the presence of pulsating combustion of the gas-air mixture, which leads to vibration of both the burner system and the combustion chamber and the engine as a whole.

The basis of the invention is the task of improving the burner system of the combustion chamber of a gas turbine of a power plant, in which, by using new structural elements, the nature of mixing fuel gas with air is changed to ensure stable combustion of the mixture with minimal underburning (СхНу) and emissions of nitrogen oxides and carbon oxides with a simultaneous reduction level and probability of occurrence of pulsating combustion and equipment vibration.

The task is solved by the fact that the design of the burner system changes without any changes to the heat pipe, air supply and mixture ignition system.

The design of the multi-channel burner of the tubular gas turbine engine with gas injection consists of two parts: central and peripheral.

These parts of the burner are separate two-chamber fuel systems, which are formed by tube boards, air tubes of the appropriate diameter and side plates of a cylindrical type, from which the fuel gas independently enters the zones of kinetic and diffusion mixture formation.

Fuel for mixture formation is supplied through gas injectors in the tubes and gas holes of the tube board.

The central part of the burner is regular and represents a fuel system separated from the peripheral part, consisting of two chambers, which are formed by tube boards, air tubes of the appropriate diameter and a side plate of a cylindrical type, and from which the fuel gas, regardless of the peripheral part, enters the zone of kinetic and diffusion mixture formation through gas injectors in the tubes and gas holes in the tube board, respectively.

The peripheral part is concentric fuel chambers of the required shape, formed by tube boards, which are tightly connected with systematically located air tubes and inner and outer side plates of a cylindrical appearance.

The inter-tube fuel space of the central and peripheral parts of the burner is divided into two fuel chambers by an intermediate pipe board: gas is supplied to the first fuel chamber along the flow of air for kinetic mixture formation, fuel is supplied to the second chamber for diffusion formation of the air-fuel mixture.

For diffusion combustion of the mixture, gas holes are made on the front tube board at a certain distance from the air tubes in a concentric circle.

Gas supply for kinetic fuel combustion is carried out through fuel injectors, which are located on the inner side surface of the air tubes at a certain distance from the inner tube board in the zone of the intertube space, with which the kinetic fuel supply channels are connected.

Thanks to this technical solution, a comprehensive positive result is achieved, namely, ensuring high-quality mixture formation, stable and efficient fuel combustion with a reduced level of harmful nitrogen oxides MOx and carbon monoxide CO

With and with the leveling of the appearance of vibrational combustion.

The design features of the invention are explained by the drawings, where:

Fig. 1 shows the general view of the multi-channel burner of the tubular type of a gas turbine engine with an injection gas supply;

Fig. 2 - longitudinal cross-section of a multi-channel burner of the tubular gas turbine type

C5 engine with injector gas supply;

Fig. C shows a view along arrow B of the frontal part of the burner.

The multi-channel burner of the tubular type gas turbine engine with gas injection differs from its analogue in that the fuel supply for diffusion and kinetic combustion is carried out separately to the central and peripheral parts of the burner through the corresponding fittings on flange 1 (Fig. 1), which are attached to the combustion chamber body and connect them with channels: 2 - fuel supply to the peripheral part for diffusion mixture formation; C - fuel supply to the peripheral part for kinetic mixture formation; 4, 5 channels - supply of fuel to the central part of the burner system for diffusion and kinetic mixture formation, respectively.

The central part of the burner system of the combustion chamber (Fig. 2) consists of air tubes b located around the axis of the central burner and a cylindrical inner wall 7, which separates it from the peripheral part of the burner.

The peripheral part is an annular chamber formed by tube boards: front 8, intermediate 9 and rear 10, which are connected by air tubes b in the form of a tube bundle, placed according to the calculated optimal geometric shape (Fig. 3) radially around the central part of the burner device.

At the required distance from the rear pipe board, there is an intermediate pipe board 9 (Fig. 2), which ensures the formation of separate inter-pipe spaces for supplying fuel to zones 11 and 12 in the peripheral part and 13 and 14 - in the central part of the burner, which perform the function fuel collectors for fuel supply for kinetic and diffusion mixture formation, respectively.

Fuel supply to the central and peripheral parts of the burner for kinetic combustion is carried out through injectors 15 and 20, which are located in air tubes 6 at a suitable distance from their end in the area of fuel collectors 11 and 13, with which the kinetic fuel supply channels 3 and 5 are connected .

Fuel holes 16 (Fig. 3) on the frontal tube board 8 of the central and peripheral parts of the burner are placed according to the appropriate scheme on the tops of regular figures. The air tubes of the central part of the burner are located accordingly to ensure high-quality fuel supply to all chambers (Fig. 3). The fuel holes for supplying fuel to the diffusion mixture formation are located concentrically relative to the axis of the air tubes.

The multi-channel tubular burner of a gas turbine engine with gas injection works as follows.

When starting the combustion chamber of a gas turbine engine, air is supplied through the central and peripheral parts of the burner system at the same time, and compressed fuel gas is supplied only to the central part of the burner through fuel channels 4 and 5 (Fig. 2) into the annular chambers 17 and 18, after which through channels 19 and through holes 16 (Fig. 3) - for diffusion mixture formation. Fuel is supplied to the kinetic mixture formation in the peripheral part of the burner through fuel injectors 20 (Fig. 2). The algorithm of operation of all channels for starting and operating the engine is selected from the conditions of ensuring optimal reliability and environmental friendliness of its operation.

The use of fuel injection for kinetic mixture formation ensures a high level of homogeneity of the fuel-air mixture at the exit from tube 6 and its efficient and environmentally friendly combustion.

After ignition of the torch on the central part of the burner, fuel is supplied to its peripheral part: fuel is fed through fuel channel 2 into the annular cavity 21, and through the fuel channel Z - into the annular cavity 22 (Fig. 2). Fuel through the channel 23 is supplied from the annular cavity 21 to the fuel collector 12 (Fig. 2), from which the fuel goes through the fuel holes 16 (Fig. 3) for diffusion combustion. The fuel from the annular cavity 22 through the channel 24 (Fig. 2) is fed into the fuel collector 11, from which through the injectors 20 in the air tubes 6, having previously mixed with the air in the tubes, it is fed to kinetic combustion.

Thanks to such a scheme of fuel supply, mixture formation and combustion of the gas-air mixture, a smooth start-up of the gas turbine engine without thermal shocks and its transfer from one load mode to another is achieved.

In addition, during the start-up period, when switching from one mode of operation of the engine to another, and during stationary mode of operation, this multi-channel burner allows you to smoothly change

From the condition of mixture formation and combustion from purely diffusive to kinetic mode, or use their optimal combination.

The use of a multi-channel burner of a tubular gas turbine engine with an injection gas supply allows to increase the efficiency of using the volume of the heat pipe for high-quality fuel combustion, and the implementation of the possibility of separate or combined regulation of fuel supply for kinetic or diffuse mixture formation allows to achieve optimal conditions for efficient and environmentally safe combustion of gaseous fuel in different modes of operation of the engine with the achievement of the minimum level of harmful emissions of nitrogen oxides and carbon monoxide.

Such a design scheme of the burner is characterized by very high stability and efficiency of fuel burning in a wide range of changes in its consumption and values of the excess air coefficient, ensures a high level of uniformity of the temperature field in the heat pipe of the combustion chamber and gases at the entrance to the blade apparatus of the gas turbine, which allows solving the problem increasing the reliability of operation and ensuring a smooth transition from one type of combustion to another and to their combination, allows to achieve high energy efficiency, meets regulatory requirements for the emission of toxic nitrogen oxides (MOx) and carbon monoxide (CO) and ensures efficient operation of the gas turbine engine combustion chamber in a wide range load range.

Claims (2)

FORMULA OF THE INVENTION 1. A multi-channel burner of a tubular type gas turbine engine with an injection gas supply, consisting of a central part and a peripheral part, which is distinguished by the fact that the specified parts of the burner are separate two-chamber fuel systems, which are formed by tube boards, air tubes of the appropriate diameter and side plates of a cylindrical type , from which the fuel gas independently enters the zones of kinetic and diffusion mixture formation. 2. A multi-channel burner of a tubular gas turbine engine with an injection gas supply according to claim 1, which is characterized by the fact that the fuel for kinetic mixture formation is supplied through gas injectors in air tubes.