阅读说明：本技术 一种燃气轮机的燃烧室及其工作方法 (Combustion chamber of gas turbine and working method thereof ) 是由 史绍平 穆延非 张波 闫姝 陈新明 于 2019-10-31 设计创作，主要内容包括：本发明公开了一种燃气轮机的燃烧室及其工作方法,包括燃烧室外壁和燃烧室内壁,所述燃烧室外壁和所述燃烧室内壁之间设有空隙形成燃烧室空气通道；所述燃烧室内壁顶部设有燃烧器,所述燃烧室内壁的侧壁设有第二风口,所述燃烧室内壁上还设置有用于控制第二风口开度的风口挡板。本发明可以在总风量保持不变的情况下,利用移动风口挡板,改变第二风口的面积,相应的增大或者减少二次风量,从而适应环境温度变化对空气密度的影响。即在冬季环境温度低,空气密度大时,增加二次风量；而在夏季环境高,空气密度小时,减少二次风量,从而提高了燃气轮机燃烧稳定性。(The invention discloses a combustion chamber of a gas turbine and a working method thereof, wherein the combustion chamber comprises a combustion chamber outer wall and a combustion chamber inner wall, and a gap is arranged between the combustion chamber outer wall and the combustion chamber inner wall to form a combustion chamber air channel; the combustor is characterized in that a combustor is arranged at the top of the inner wall of the combustor, a second air port is formed in the side wall of the inner wall of the combustor, and an air port baffle plate used for controlling the opening degree of the second air port is further arranged on the inner wall of the combustor. The invention can change the area of the second air port by utilizing the movable air port baffle plate under the condition that the total air volume is not changed, and correspondingly increase or reduce the secondary air volume, thereby adapting to the influence of the change of the environmental temperature on the air density. Namely, when the environmental temperature is low and the air density is high in winter, the secondary air quantity is increased; and in summer, the environment is high, the air density is small, the secondary air quantity is reduced, and therefore the combustion stability of the gas turbine is improved.)

1. The combustor of the gas turbine is characterized by comprising a combustor outer wall (1) and a combustor inner wall (3), wherein a gap is formed between the combustor outer wall (1) and the combustor inner wall (3) to form a combustor air channel; the combustor top is equipped with combustor (4), the lateral wall of combustor inner wall (3) is equipped with second wind gap (2), still be provided with wind gap baffle (5) that are used for controlling second wind gap (2) aperture on combustor inner wall (3).

2. The combustion chamber of the gas turbine as claimed in claim 1, wherein a limit baffle (6) is further arranged on the inner wall (3) of the combustion chamber, the limit baffle (6) is arranged below the second tuyere (2), and the limit baffle (6) is used for limiting the tuyere baffle (5).

3. The combustion chamber of a gas turbine according to claim 1, characterized in that the tuyere stock (5) is fitted over the combustion chamber inner wall (3), the tuyere stock (5) being axially movable along the combustion chamber inner wall (3), the tuyere stock (5) covering or being distanced from the second tuyere (2) by an axial movement in the combustion chamber inner wall (3).

4. A combustion chamber of a gas turbine according to claim 1, characterized in that said second tuyere (2) is provided in plurality, and the plurality of second tuyeres (2) are evenly distributed on the same level of the inner wall (3) of the combustion chamber.

5. A combustion chamber of a gas turbine according to claim 1, characterized in that the end of the combustion chamber air channel is connected to a compressor outlet (7), a plurality of burners (4) are arranged in an annular array at the top of the combustion chamber, and the bottom of the combustion chamber is connected to a turbine inlet (8).

6. A combustion chamber of a gas turbine according to claim 1, characterized in that the tuyere stock (5) is of an annular configuration having a width such that it completely covers the second tuyere (2) arranged in the side wall of the combustion chamber inner wall (3).

7. A combustion chamber of a gas turbine according to claim 1, characterized in that the tuyere stock (5) is clearance fitted to the inner wall (3) of the combustion chamber.

8. Method of operating a combustion chamber of a gas turbine according to any of the claims 1 to 7, characterized in that the secondary air flow needs to be reduced when the ambient temperature increases, the opening of the secondary air port (2) needs to be reduced by moving the port shutter (5), the secondary air flow needs to be increased when the ambient temperature decreases, and the opening of the secondary air port (2) needs to be increased by moving the port shutter (5).

9. Method of operating a combustion chamber of a gas turbine according to claim 8, characterized in that the distance L over which the tuyere stock (5) is moved is linear with the ambient temperature T as follows:

L＝a(T_max-T)

in the formula: a is a correlation coefficient, T_maxThe maximum ambient temperature.

Technical Field

The invention relates to the technical field of gas turbines, in particular to a combustion chamber of a gas turbine and a working method thereof.

Background

When the environmental temperature of a gas turbine system of a power station is low in winter, the flame combustion in a combustion chamber is unstable, and the frequent occurrence of an alarm signal with the duration of more than 0.4s and the pressure fluctuation of more than 80mbar detected by an inner path buzzing monitoring system of the combustion chamber is mainly shown. The environment temperature and the buzzing signal have consistent correlation, and the buzzing disappears when the environment temperature is higher; the lower the ambient temperature, the more frequent the beeps. Frequent buzzer alarming can not only lead to the working condition that the fuel is switched back to the fuel oil after passing the fuel or the trip event, but also possibly cause accidents such as cracks of the heat insulation tile of the combustion chamber and the like.

Two main reasons influencing the combustion stability operation of a combustion chamber of a gas turbine are obtained through theoretical calculation and analysis, on one hand, the air density is improved due to the reduction of the ambient temperature in winter, and the mass flow of the air at the inlet of the combustion chamber is increased under the condition that the angle of an inlet guide vane of a gas compressor is not changed; on the other hand, the ambient temperature is reduced in winter, which also results in a reduction in the combustor inlet air temperature.

Disclosure of Invention

The present invention is directed to solving the above problems, and an object of the present invention is to provide a combustion chamber of a gas turbine and a method for operating the same, in which the relative ratio of primary air and secondary air in the combustion chamber is adjusted to adapt to the change of ambient temperature, thereby improving the combustion stability of the combustion chamber of the gas turbine.

In order to achieve the purpose, the invention adopts the following technical scheme:

a combustion chamber of a gas turbine comprises a combustion chamber outer wall and a combustion chamber inner wall, wherein a gap is arranged between the combustion chamber outer wall and the combustion chamber inner wall to form a combustion chamber air channel; the combustor top is equipped with the combustor, the lateral wall of combustor inner wall is equipped with the second wind gap, still be provided with the wind gap baffle that is used for controlling the second wind gap aperture on the combustor inner wall.

Furthermore, a limit baffle is further arranged on the inner wall of the combustion chamber, the limit baffle is arranged below the second air port, and the limit baffle is used for limiting the air port baffle.

Furthermore, the air port baffle is sleeved on the inner wall of the combustion chamber, the air port baffle can axially move along the inner wall of the combustion chamber, and the air port baffle covers or is far away from the second air port through the axial movement on the inner wall of the combustion chamber.

Furthermore, the second air ports are provided with a plurality of air ports, and the plurality of air ports are uniformly distributed on the same height of the inner wall of the combustion chamber.

Furthermore, the tail end of the air channel of the combustion chamber is connected with an outlet of the compressor, a plurality of combustor annular arrays are arranged at the top of the combustion chamber, and the bottom of the combustion chamber is connected with an inlet of the turbine.

Furthermore, the tuyere baffle is of an annular structure, and the width of the annular structure can completely cover the second tuyere arranged on the side wall of the inner wall of the combustion chamber.

Furthermore, clearance fit is formed between the tuyere baffle and the inner wall of the combustion chamber.

The invention also provides a working method of the combustion chamber of the gas turbine, when the secondary air quantity needs to be reduced, the opening degree of the second air port is reduced by moving the air port baffle, and when the secondary air quantity needs to be increased, the opening degree of the second air port is increased by moving the air port baffle away from the second air port.

Further, the moving distance L of the tuyere baffle and the ambient temperature T are in a linear relationship as follows:

L＝a(T_max-T)

in the formula: a is a correlation coefficient, the magnitude of which can be determined by experiment, T_maxAt the maximum ambient temperature, T_maxThe maximum ambient temperature.

Compared with the prior art, the invention has at least the following beneficial effects:

the invention provides a combustion chamber of a gas turbine, which realizes secondary air volume and primary air volume of the combustion chamber of the gas turbine through an air port baffle and a second air port arranged on the inner wall of the combustion chamber.

According to the invention, the movement distance of the air port baffle is limited by the limiting baffle, so that the movement distance of the air port baffle can be shortened, and the opening degree of the second air port is increased or reduced more efficiently.

The moving distance of the tuyere baffle plate has a functional relation with the ambient temperature, and the moving distance of the tuyere baffle plate can be accurately selected according to the change of the ambient temperature, so that the combustion of the combustion chamber of the gas turbine is more sufficient.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

In the drawings: the device comprises a combustion chamber outer wall 1, a combustion chamber inner wall 3, a combustor 4, a tuyere baffle 5, a baffle limit 6, a compressor outlet 7, a turbine inlet 8 and fuel 9.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in figure 1, the combustion chamber of the gas turbine for improving the combustion stability is in a barrel shape and mainly comprises a combustion chamber outer wall 1 and a combustion chamber inner wall 3, and a gap is arranged between the combustion chamber outer wall 1 and the combustion chamber inner wall 3 to form a combustion chamber air channel; the top of the combustion chamber is provided with a combustor 4, a plurality of second air ports 2 are uniformly distributed on the same height of the inner wall 3 of the combustion chamber, and an air port baffle plate 5 is sleeved on the inner wall 3 of the combustion chamber; the tuyere baffle 5 covers or is far away from the second tuyere 2 through axial movement on the inner wall 3 of the combustion chamber; the tail end of the air channel of the combustion chamber is connected with an air compressor outlet 7, the bottom of the combustion chamber is connected with a turbine inlet 8, a limiting baffle 6 is further arranged on the inner wall 3 of the combustion chamber, the limiting baffle 6 is arranged below the second air port 2, and the limiting baffle 6 is used for limiting the air port baffle 5. .

Air compressed by the gas compressor of the gas turbine directly enters an air channel between the outer wall 1 of the combustion chamber and the inner wall 3 of the combustion chamber from an outlet 7 of the gas compressor, enters the combustion chamber from the combustor 4 through an air inlet hole and a fuel 9 to be combusted, wherein the air entering the combustor 4 is called primary air, the air entering the second air port 2 is called secondary air to assist further combustion, and high-temperature flue gas generated by combustion enters a turbine inlet 8.

When a general gas turbine works at rated load, the inlet guide vanes of the gas compressor are fully opened, and the volume flow of inlet air of the gas compressor is kept unchanged. However, when the ambient temperature changes, the density of the air also changes along with the change of the ambient temperature, and the density of the air at 30 ℃ in summer is about 1.1466kg/m³The temperature of the winter environment is about 30-40 ℃ lower than that of the summer environment, so that the air density is relatively increased by 0.1651kg/m³～0.1279kg/m³I.e. the air density is about 10% in winter compared to summer.

The environmental temperature is lower in winter, and the mass flow is higher due to higher density although the volume flow of air at the inlet of the air compressor is unchanged; this is also the main cause of unstable combustion in the combustion chamber; the size of the second tuyere 2 can be increased by moving the tuyere baffle 5, so that the secondary air quantity is increased, and the combustion chamber can be fully combusted.

When the temperature is higher in summer, the size of the second air port 2 is reduced through the movement of the air port baffle plate 5, so that the secondary air quantity is reduced.

The height of the air port baffle 5 in movement is in a certain functional relation with the ambient temperature, and can be controlled by a servo motor, so that the automatic adjustment of the height of the air port baffle can be realized according to the ambient temperature. The distance L traveled as a function of the ambient temperature T is given by the following equation, where a is a correlation coefficient whose magnitude can be determined experimentally and T is_maxThe maximum ambient temperature.

L＝a(T_max-T)

The details of the present invention not described in detail are prior art.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.