KR102152420B1 - Combustor, gas turbine, and operating method of combustor - Google Patents

Abstract

The present invention provides a combustor capable of efficiently reducing nitrogen oxides, and an operating method of the combustor. According to one aspect of the present invention, the combustor comprises: a burner having a plurality of main nozzles which spray fuel and air; a duct assembly which is coupled to one side of the burner, in which the fuel and the air are burnt, and which transfers the combustion gas to a turbine; and a side nozzle placed on a lower side than the main nozzles and coupled to an outer circumferential surface of the duct assembly. The side nozzle includes: a side tube where fuel and air are mixed; a center fuel chamber installed in the side tube to spray fuel; a middle fuel chamber placed on a more external side than the center fuel chamber; a first fuel supply pipe connected to the center fuel chamber; and a second fuel supply pipe connected to the middle fuel chamber.

Description

A combustor, a gas turbine including the same, and a method of driving a combustor {COMBUSTOR, GAS TURBINE, AND OPERATING METHOD OF COMBUSTOR}

The present invention relates to a combustor, a gas turbine and a method of driving a combustor.

A gas turbine is a power engine that mixes and combusts compressed air and fuel compressed by a compressor, and rotates the turbine with hot gas generated by combustion. Gas turbines are used to drive generators, aircraft, ships, and trains.

Gas turbines generally include compressors, combustors and turbines. The compressor sucks in outside air, compresses it, and delivers it to the combustor. The air compressed by the compressor is in a state of high pressure and high temperature. The combustor combusts by mixing fuel and compressed air introduced from the compressor. The combustion gases generated by combustion are discharged to the turbine. The turbine blades inside the turbine are rotated by the combustion gas, and power is generated through this. The generated power is used in various fields such as power generation and driving of mechanical devices.

Fuel is injected through nozzles installed in each combustor, and gaseous fuel may be premixed and injected inside the nozzle. In order to reduce nitrogen oxides, the combustion temperature of the fuel must be controlled within a preset range. In particular, in order to stabilize the flame in the combustor, the supplied fuel must be precisely controlled, but the conventional combustor nozzle has a problem in that the fuel and air are not uniformly mixed and the stability of the combustion process is low.

Based on the above technical background, the present invention provides a combustor capable of efficiently reducing nitrogen oxides and a method of driving the combustor.

The combustor according to an aspect of the present invention is a burner having a plurality of main nozzles for injecting fuel and air, a duct assembly that is coupled to one side of the burner, the fuel and the air are burned inside, and delivers the burned gas to the turbine And a side nozzle disposed downstream of the main nozzle and coupled to an outer circumferential surface of the duct assembly, wherein the side nozzle is installed in a side tube in which fuel and air are mixed and a center for injecting fuel And a fuel chamber, a middle fuel chamber positioned further outside the center fuel chamber, a first fuel supply pipe connected to the center fuel chamber, and a second fuel supply pipe connected to the middle fuel chamber.

Here, a first valve for controlling a flow rate of fuel moving through the first fuel supply pipe is installed in the first fuel supply pipe, and a flow rate of fuel moving through the second fuel supply pipe is controlled in the second fuel supply pipe A second valve may be installed.

In addition, the middle fuel chamber may be formed of a pipe connected in an annular shape, and a plurality of injection holes may be formed in the middle fuel chamber.

In addition, the center fuel chamber may have a spherical shape, and a plurality of injection holes may be formed in the center fuel chamber.

In addition, a plurality of center swirlers may be formed between the center fuel chamber and the middle fuel chamber to connect the center fuel chamber and the middle fuel chamber and guide the flow of air.

In addition, the center swirler may include a passage connected to the middle fuel chamber to receive fuel and an injection hole through which fuel accommodated in the passage is discharged.

In addition, the side nozzle may further include an outer fuel chamber positioned further outside the middle fuel chamber and injecting fuel.

In addition, a plurality of middle swirlers may be formed between the middle fuel chamber and the outer fuel chamber to connect the middle fuel chamber and the outer fuel chamber and guide the flow of air.

In addition, the center swirler and the middle swirler may be formed to be inclined in different directions.

In addition, a plurality of outer swirlers protruding outward are formed in the outer fuel chamber, and the outer swirlers may connect the outer fuel chamber and the side tube.

In addition, a third fuel supply pipe for supplying fuel to the outer fuel chamber is connected to the outer fuel chamber, and a third valve for controlling a flow rate of fuel moving through the third fuel supply pipe is installed in the third fuel supply pipe. Can be.

In addition, the combustor is a side control unit that decreases the amount of fuel supplied to the first fuel supply pipe and increases the amount of fuel supplied to the second fuel supply pipe when the total amount of fuel supplied to the side nozzle decreases. It may further include.

In addition, the combustor includes a side control unit for increasing the amount of fuel supplied to the first fuel supply pipe and reducing the amount of fuel supplied to the second fuel supply pipe when the amount of fuel supplied to the side nozzle increases. It may contain more.

In addition, the middle fuel chamber may be formed outside the side tube and formed of a tube connected in a circumferential direction of the side tube, and a plurality of injection holes connected to the middle fuel chamber may be formed in the side tube.

The combustor according to another aspect of the present invention is a burner having a plurality of main nozzles for injecting fuel and air, a duct assembly that is coupled to one side of the burner, the fuel and the air are burned inside, and delivers the burned gas to the turbine And a side nozzle disposed downstream of the main nozzle and coupled to an outer circumferential surface of the duct assembly, wherein the side nozzle is installed in a side tube in which fuel and air are mixed and a center for injecting fuel It includes a fuel chamber and a middle fuel chamber positioned further outside the center fuel chamber, and a side control unit for controlling flow rates of fuel injected from the center fuel chamber and the middle fuel chamber to be inversely proportional.

A gas turbine according to another aspect of the present invention includes a compressor for compressing air introduced from the outside, a combustor for combusting by mixing compressed air and fuel compressed by the compressor, and a plurality of rotating by combustion gases combusted in the combustor. A gas turbine including a turbine including a turbine blade, wherein the combustor is a burner having a plurality of main nozzles for injecting fuel and air, and is coupled to one side of the burner, and the fuel and the air are combusted and burned. A duct assembly for transmitting gas to the turbine, and a side nozzle disposed downstream of the main nozzle and coupled to an outer circumferential surface of the duct assembly, wherein the side nozzle includes a side tube in which fuel and air are mixed and the side tube And a center fuel chamber installed in and injecting fuel, a middle fuel chamber positioned further outside the center fuel chamber, a first fuel supply pipe connected to the center fuel chamber, and a second fuel supply pipe connected to the middle fuel chamber.

A method of driving a combustor according to another aspect of the present invention includes a main flame generating step of generating a main flame by injecting fuel through a main nozzle coupled to a longitudinal end of the duct assembly, and a side nozzle installed on the outer peripheral surface of the duct assembly. Delayed flame generation step of generating a delayed flame by injecting fuel through the side nozzle, the overall fuel control step of adjusting the flow rate of the fuel supplied through the side nozzle, and located at the center of the side nozzle according to the flow rate supplied to the side nozzle And a chamber fuel control step of controlling a flow rate of the fuel supplied to the center fuel chamber for injecting fuel and the middle fuel chamber for injecting fuel by being located further outside the center fuel chamber.

Here, in the chamber fuel control step, when the fuel flow rate supplied in the total fuel control step increases, the flow rate of the fuel supplied to the center fuel chamber is increased, and the flow rate of the fuel supplied to the middle fuel chamber is decreased. I can.

Further, in the chamber fuel control step, when the fuel flow rate supplied in the total fuel control step decreases, the flow rate of the fuel supplied to the center fuel chamber is reduced, and the flow rate of the fuel supplied to the middle fuel chamber is increased. I can.

In addition, the chamber fuel control step includes detecting a change in flow rate of all fuel supplied to the side nozzle, controlling a first valve installed in a first fuel supply pipe connected to the center fuel chamber, and controlling a first valve connected to the middle fuel chamber. It may include controlling the second valve installed in the second fuel supply pipe.

As described above, the combustor according to an aspect of the present invention may have a side nozzle to reduce nitrogen oxides and provide greater energy to the combustion gas.

In addition, since a fuel supply pipe is separately connected to each of the center fuel chamber and the middle fuel chamber, the equivalent ratio of the pre-mixed air injected from the side nozzle can be controlled to stabilize the flame and prevent backfire.

1 is a view showing the interior of a gas turbine according to a first embodiment of the present invention.
2 is a view showing the combustor of FIG. 1.
3 is a cross-sectional view of a side nozzle cut in the radial direction according to the first embodiment of the present invention.
4 is a cross-sectional view of a side nozzle cut in the longitudinal direction according to the first embodiment of the present invention.
5 is a flow chart illustrating a method of operating a combustor according to the first embodiment of the present invention.
6 is a cross-sectional view of a side nozzle according to a second embodiment of the present invention cut in the longitudinal direction.
7 is a cross-sectional view of a side nozzle cut in a radial direction according to a third embodiment of the present invention.
8 is a partial cross-sectional view of a side nozzle according to a third embodiment of the present invention cut in the longitudinal direction.

The present invention is intended to illustrate specific embodiments and to be described in detail in the detailed description, since various transformations can be applied and various embodiments can be provided. However, this is not intended to limit the present invention to a specific embodiment, it is to be understood to include all conversions, equivalents, and substitutes included in the spirit and scope of the present invention.

The terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present invention, terms such as'comprise' or'have' are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, it should be noted that in the accompanying drawings, the same components are indicated by the same reference numerals as possible. In addition, detailed descriptions of known functions and configurations that may obscure the subject matter of the present invention will be omitted. For the same reason, some components in the accompanying drawings are exaggerated, omitted, or schematically illustrated.

Hereinafter, a gas turbine according to a first embodiment of the present invention will be described.

1 is a view showing the interior of a gas turbine according to an embodiment of the present invention, FIG. 2 is a view showing the combustor of FIG.

The thermodynamic cycle of the gas turbine 1000 according to this embodiment can ideally follow the Brayton cycle. The Brayton cycle can consist of four processes leading to isentropic compression (thermal compression), static pressure rapid heating, isentropic expansion (thermal expansion), and static pressure heat dissipation. In other words, after inhaling atmospheric air and compressing it to high pressure, it burns fuel in a static pressure environment to release thermal energy, expands the high-temperature combustion gas and converts it into kinetic energy, and then releases exhaust gas containing residual energy into the atmosphere. I can. That is, the cycle can be performed in four processes of compression, heating, expansion, and heat dissipation.

The gas turbine 1000 realizing the above Brayton cycle may include a compressor 1100, a combustor 1200, and a main turbine 1300, as shown in FIG. 1. Although the following description will refer to FIG. 1, the description of the present invention can be widely applied to a turbine engine having a configuration equivalent to that of the gas turbine 1000 illustrated in FIG. 1 by way of example.

Referring to FIG. 1, a compressor 1100 of a gas turbine 1000 may suck air from the outside and compress it. The compressor 1100 may supply compressed air compressed by the compressor blade 1130 to the combustor 1200, and may also supply cooling air to a high temperature region requiring cooling in the gas turbine 1000. At this time, since the sucked air undergoes an adiabatic compression process in the compressor 1100, the pressure and temperature of the air passing through the compressor 1100 are increased.

The compressor 1100 is designed as centrifugal compressors or axial compressors. While a centrifugal compressor is applied in a small gas turbine, a large gas turbine 1000 as shown in FIG. 1 is a large amount of air. It is common to apply the multi-stage axial compressor 1100 because it must be compressed. At this time, in the multi-stage axial compressor 1100, the blades 1130 of the compressor 1100 rotate according to the rotation of the rotor disk to compress the introduced air and move the compressed air to the compressor vanes 1140 at the rear stage. As the air passes through the compressor blades 1130 formed in multiple stages, it is compressed to a higher pressure.

The compressor vane 1140 is mounted inside the housing 1150, and a plurality of compressor vanes 1140 may be mounted to form stages. The compressor vane 1140 guides the compressed air moved from the compressor blade 1130 at the front to the blade 1130 at the rear end. In one embodiment, at least some of the plurality of compressor vanes 1140 may be mounted so as to be rotatable within a predetermined range for adjusting the inflow amount of air.

The compressor 1100 may be driven using a portion of the power output from the main turbine 1300. To this end, as shown in FIG. 1, the rotation axis of the compressor 1100 and the rotation axis of the main turbine 1300 may be directly connected. In the case of the large gas turbine 1000, almost half of the output produced by the main turbine 1300 may be consumed to drive the compressor 1100. Therefore, improving the efficiency of the compressor 1100 has a direct effect on improving the overall efficiency of the gas turbine 1000. The air compressed by the compressor 1100 is introduced into the vehicle compartment 1180 where the duct assembly 1280 of the combustor 1200 is located.

On the other hand, the combustor 1200 may mix compressed air supplied from the outlet of the compressor 1100 with fuel and burn at an isostatic pressure to produce a high-energy combustion gas. 2 shows an example of a combustor 1200 applied to the gas turbine 1000. The combustor 1200 may include a combustor casing 1210, a burner 1220, a main nozzle 1230, a side nozzle 1500, and a duct assembly 1280. The gas turbine 1000 includes a plurality of combustors 1200, and the combustors 1200 may be arranged along the circumferential direction of the shaft.

The combustor casing 1210 may surround the plurality of burners 1220 and may have a substantially circular shape. The burner 1220 is disposed downstream of the compressor 1100 and may be disposed along the combustor casing 1210 forming an annular shape. Each burner 1220 is provided with several main nozzles 1230, and the fuel injected from the main nozzle 1230 is mixed with air in an appropriate ratio to achieve a state suitable for combustion.

Gas fuel and liquid fuel, or a combination fuel of a gas fuel and a liquid fuel, or a combination thereof may be used for the gas turbine 1000. It is important to create a combustion environment to reduce the amount of emission gases such as carbon monoxide and nitrogen oxides, which are subject to legal regulations. Although combustion control is relatively difficult, it has the advantage of lowering the combustion temperature and creating uniform combustion to reduce emission gas. In recent years, premixed combustion is widely applied.

In the case of premixed combustion, compressed air is mixed with fuel previously injected from the nozzle 1230 and then enters into the combustion chamber 1240. The initial ignition of the premixed gas is performed using an igniter, and when combustion is stabilized, fuel and air are supplied to maintain combustion.

Compressed air flows along the outer surface of the duct assembly 1280 through which the high-temperature combustion gas flows by connecting between the burner 1220 and the turbine 1300 and is supplied to the nozzle 1230. In this process, the high-temperature combustion gas The heated duct assembly 1280 is properly cooled.

The duct assembly 1280 may include a liner 1250, a transition piece 1260, and a flow sleeve 1270. The duct assembly 1280 has a dual structure in which the liner 1250 and the flow sleeve 1270 surround the outside of the transition piece 1260, and an annular cooling passage through which cooling air moves inside the flow sleeve 1270 (1281) is formed. The compressed air penetrates into the cooling passage 1281 inside the flow sleeve 1270 to cool the liner 1250 and the transition piece 1260.

Air discharged from the compressor 1100 is introduced into the vehicle compartment 1180 into which the duct assembly 1280 is inserted, and the air introduced into the vehicle compartment 1180 is cooled through a hole formed on the outer surface of the flow sleeve 1270. ) To cool the liner 1250 and the transition piece 1260.

The liner 1250 is a tubular member connected to the burner 1220 of the combustor 1200, and a space inside the liner 1250 forms the combustion chamber 1240. One end of the liner 1250 in the longitudinal direction is coupled to the burner 1220 and the other end of the liner 1250 in the longitudinal direction is coupled to the transition piece 1260.

Further, the transition piece 1260 is connected to the inlet of the turbine 1300 and serves to guide the high-temperature combustion gas to the turbine 1300. One end of the transition piece 1260 in the longitudinal direction is coupled to the liner 1250, and the other end of the transition piece 1260 in the longitudinal direction is coupled to the turbine 1300. The flow sleeve 1270 serves to protect the liner 1250 and the transition piece 1260 and prevent hot heat from being directly discharged to the outside.

As shown in FIG. 1, the high-temperature, high-pressure combustion gas produced in the combustor 1200 is supplied to the main turbine 1300 through a duct assembly 1280. In the main turbine 1300, the combustion gas is adiabaticly expanded and collides with a plurality of blades 1310 arranged radially on the rotating shaft of the main turbine 1300, and the thermal energy of the combustion gas is converted into mechanical energy in which the rotating shaft rotates. do. Some of the mechanical energy obtained from the main turbine 1300 is supplied as energy required to compress air in the compressor 1100, and the remainder is utilized as effective energy such as generating power by driving a generator.

As shown in FIG. 2, the main nozzle 1230 is coupled to the longitudinal end of the duct assembly 1280 to inject fuel and air. The main nozzle 1230 is fixed to the end plate 1221 and supplied with fuel from the end plate 1221, and premixed air is injected in the direction of the central axis X1 of the duct assembly 1280 to generate the main flame MF. Can be formed.

3 is a cross-sectional view of a side nozzle cut in the radial direction according to the first embodiment of the present invention, and FIG. 4 is a cross-sectional view of a side nozzle according to the first embodiment of the present invention, cut in the longitudinal direction.

3 and 4, the side nozzle 1500 is disposed downstream of the main nozzle 1230 (based on the traveling direction of the burned hot gas) and is coupled to the outer peripheral surface of the duct assembly 1280. Can be. The side nozzle 1500 may be installed to penetrate the liner 1250 and the flow sleeve 1270. However, the present invention is not limited thereto, and the side nozzle 1500 may be installed to penetrate the transition piece 1260 and the flow sleeve 1270. The side nozzle 1500 may inject fuel in a direction crossing the central axis X1 of the burner 1220 to form a delay flame LF. The side nozzle 1500 may inject fuel in a direction perpendicular to the central axis X1 of the burner 1220 or inclined toward the main turbine 1300 to inject fuel. Fuel supplied to the side nozzle 1500 may be formed of gas or liquid.

The side nozzle 1500 includes a fuel chamber assembly 1520, a first fuel supply pipe 1531, a second fuel supply pipe 1532, and a third fuel chamber assembly 1520 installed in the side tube 1510 and the side tube 1510 where fuel and air are mixed. A fuel supply pipe 1533, a side fuel supply pipe 1535, a first valve 1541, a second valve 1542, a third valve 1543, a main control valve 1545, and a side control unit 1590 may be included. .

The side tube 1510 is made of a substantially circular tube, and the front end of the side tube 1510 may be fixed to the duct assembly 1280. The side tube 1510 may include a transmission pipe portion 1511 having a uniform diameter and a variable pipe portion 1512 connected to the transmission pipe portion 1511 and decreasing in cross-sectional area toward the tip. The fuel chamber assembly 1520 may be installed at a portion connected to the transmission pipe portion 1511 and the variable pipe portion 1512.

The front end of the side tube 1510 is connected to the inside of the duct assembly 1280, and the rear end of the side tube 1510 is connected to the vehicle compartment 1180. Accordingly, the compressed air supplied to the vehicle compartment 1180 may be injected into the duct assembly 1280 through the side tube 1510. The side tube 1510 injects air mixed with fuel into the duct assembly 1280, and the pre-mixed air injected from the side tube 1510 meets the hot gas inside the duct assembly 1280 to cause a delay flame (LF). To form. The delay flame LF is formed on the downstream side of the main flame MF (based on the moving direction of the hot gas) to increase the energy of the hot gas.

The fuel chamber assembly 1520 includes a plurality of fuel chambers and swirlers installed in the side tube 1510 to inject fuel. The fuel chamber assembly includes a center fuel chamber 1521 disposed at the center of the side tube, a middle fuel chamber 1522 disposed further outside the center fuel chamber 1521, and an outer fuel disposed further outside the middle fuel chamber 1522. A chamber 1523 may be included.

The center fuel chamber 1521 has a substantially spherical shape, and a first fuel supply pipe 1531 is connected to a rear end of the center fuel chamber 1521. A plurality of injection holes 1521a may be formed in the center fuel chamber 1521.

The middle fuel chamber 1522 is disposed concentrically with the center fuel chamber 1521, and may be formed of an annular tube surrounding the center fuel chamber 1521. A second fuel supply pipe 1532 may be connected to the middle fuel chamber 1522, and a plurality of injection holes 1522a may be formed in the middle fuel chamber 1522.

The outer fuel chamber 1523 is disposed concentrically with the middle fuel chamber 1522, and may be formed of an annular tube surrounding the middle fuel chamber 1522. A third fuel supply pipe 1533 is connected to the outer fuel chamber 1523, and a plurality of injection holes 1523a may be formed in the outer fuel chamber 1523.

The fuel chamber assembly 1520 may further include a plurality of center swirlers 1524, a middle swirler 1525, and an outer swirler 1526. The center swirler 1524 connects the center fuel chamber 1521 and the middle fuel chamber 1522 between the center fuel chamber 1521 and the middle fuel chamber 1522 to guide the flow of air. The plurality of center swirlers 1524 are arranged spaced apart in the circumferential direction of the center fuel chamber 1521. The center swirler 1524 is made of a plate having a length direction and a width direction, and the width direction of the center swirler 1524 is disposed to be inclined with respect to the radial direction of the side tube 1510. The center swirler 1524 may be disposed to be inclined so that the clockwise side end is located more rearward than the opposite side end.

The plurality of middle swirlers 1525 connect the middle fuel chamber 1522 and the outer fuel chamber 1523 between the middle fuel chamber 1522 and the outer fuel chamber 1523 and guide the flow of air. The plurality of middle swirlers 1525 are spaced apart from each other in the circumferential direction of the middle fuel chamber 1522. The middle swirler 1525 is made of a plate having a length direction and a width direction, and the width direction of the middle swirler 1525 is disposed to be inclined with respect to the radial direction of the side tube 1510. The width direction of the middle swirler 1525 may be formed to be inclined in a direction different from the width direction of the center swirler 1524. That is, when the center swirler 1524 is located at a clockwise side end more rearward than an opposite side end, the middle swirler 1525 may be inclined so that the clockwise side end is located more forward than the opposite end.

The plurality of outer swirlers 1526 protrude to the outside of the outer fuel chamber 1523 and connect the outer fuel chamber 1523 and the side tube 1510. A plurality of outer swirlers 1526 are arranged spaced apart in the circumferential direction of the outer fuel chamber 1523. The outer swirler 1526 is disposed to be inclined in a direction different from that of the middle swirler 1525, and may be disposed to be inclined in the same direction as the center swirler 1524.

When the swirler is formed between the fuel chambers as in the first embodiment, it is possible to more evenly mix the air and fuel and stabilize the flame by inducing a vortex of air. In addition, when each swirler is disposed to be inclined in a different direction from the neighboring swirler, a vortex that rotates in different directions is formed in a section in which each swirler is located, so that air and fuel can be more uniformly mixed.

A first valve 1541 for controlling a flow rate of fuel moving through the first fuel supply pipe 1531 is installed in the first fuel supply pipe 1531, and a second fuel supply pipe 1532 in the second fuel supply pipe 1532 A second valve 1542 for controlling the flow rate of fuel moving through the fuel is installed, and a third valve 1543 for controlling the flow rate of fuel moving through the third fuel supply pipe 1533 is installed in the third fuel supply pipe 1533. ) Can be installed. In addition, the first fuel supply pipe 1531, the second fuel supply pipe 1532, and the third fuel supply pipe 1533 are connected to the side fuel supply pipe 1535, and the main control valve 1545 is installed in the side fuel supply pipe 1535. I can. The side fuel supply pipe 1535 supplies fuel to the first fuel supply pipe 1531, the second fuel supply pipe 1532, and the third fuel supply pipe 1533, and the main control valve 1545 is supplied through the side nozzle 1500. It controls the total fuel flow rate.

On the other hand, the side control unit 1590 not only controls the total fuel flow rate supplied through the side nozzle 1500, but also through the first fuel supply pipe 1531, the second fuel supply pipe 1532, and the third fuel supply pipe 1533. It controls the flow rate of the supplied fuel.

The side control unit 1590 may control the fuel flow rate moving to the side fuel supply pipe 1535 through the main control valve 1545, and thereby control the total fuel flow rate injected through the side nozzle 1500.

The side control unit 1590 may increase or decrease the fuel flow rate supplied to the side fuel supply pipe 1535 according to the state of the main flame MF. For example, when the main flame MF is unstable and a condition in which a lot of nitrogen oxides are generated is formed, the side control unit 1590 may decrease nitrogen oxides by increasing the flow rate of the fuel supplied to the side fuel supply pipe 1535. In addition, when the main flame MF is stabilized to form a condition in which the generation of nitrogen oxides is reduced, the side control unit 1590 may reduce the fuel flow rate supplied to the side fuel supply pipe 1535.

When the fuel flow rate moving through the side fuel supply pipe 1535 increases, the side control unit 1590 increases the amount of fuel supplied to the first fuel supply pipe 1531, and the second fuel supply pipe 1532 and the third The amount of fuel supplied to the fuel supply pipe 1533 may be reduced. When the flow rate of the fuel supplied to the first fuel supply pipe 1531 increases, the equivalent ratio of the high temperature region increases, so that the flame can be stably formed.

In addition, when the fuel flow rate moving through the side fuel supply pipe 1535 decreases, the side control unit 1590 reduces the amount of fuel supplied to the first fuel supply pipe 1531, and the second fuel supply pipe 1532 and The flow rate of the fuel supplied to the third fuel supply pipe 1533 may be increased.

If the flow rate of the fuel supplied to the second fuel supply pipe 1532 and the third fuel supply pipe 1533 increases, backfire can be prevented by lowering the equivalent ratio in the high temperature region when there is a risk of backfire. The increase and decrease of the fuel flow rate may be made within a range of 5 wt% to 50 wt% of a preset reference flow rate.

As described above, the side control unit 1590 controls the flow rates of fuel injected from the center fuel chamber 1521 and the middle fuel chamber 1522 to be inversely proportional. That is, the side control unit 1590 may decrease the fuel flow rate supplied to the middle fuel chamber 1522 when increasing the fuel flow rate supplied to the center fuel chamber 1521.

Hereinafter, a method for controlling a combustor according to a first embodiment of the present invention will be described. 5 is a flow chart illustrating a method of operating a combustor according to the first embodiment of the present invention.

Referring to FIG. 5, the operation method of the combustor according to the first embodiment includes a main flame generation step (S101), a delayed flame generation step (S102), a total fuel control step (S103), and a chamber fuel control step (S105). ).

In the main flame generating step S101, fuel is injected through the main nozzle 1230 coupled to the longitudinal end of the duct assembly 1280 to generate the main flame MF. In the delayed flame generation step (S102), fuel is injected through the side nozzle 1500 installed on the outer circumferential surface of the duct assembly 1280 to generate the delayed flame LF. The delay flame LF is formed further downstream than the main flame MF, and a plurality of side nozzles 1500 spaced apart in the circumferential direction are installed on the outer circumferential surface of the duct assembly 1280 so that a plurality of delay flames LF are provided. Can be formed. In the delayed flame generation step (S102), a vortex is formed using the center swirler 1524, the middle swirler 1525, and the outer swirler 1526, and the fuel and air are mixed to form the delayed flame LF. have.

In the overall fuel control step (S103), the flow rate of the fuel injected through the side nozzle 1500 is adjusted. The overall fuel control step S103 may be performed by the side control unit 1590. When the main flame MF is unstable, the total fuel control step S103 may increase the flow rate of fuel injected through the side nozzle 1500. When the main flame MF is stable, the total fuel control step S103 may reduce the flow rate of the fuel injected through the side nozzle.

In the chamber fuel control step S105, flow rates of fuel supplied to the center fuel chamber 1521, the middle fuel chamber 1522, and the outer fuel chamber 1523 are adjusted according to the flow rate supplied to the side nozzle 1500. The chamber fuel control step S105 may be performed by the side control unit 1590.

The chamber fuel control step (S105) includes a step of detecting a change in the flow rate of the total fuel supplied to the side nozzle 1500 and a first valve 1541 installed in the first fuel supply pipe 1531 connected to the center fuel chamber 1521. Controlling and controlling the second valve 1542 installed in the second fuel supply pipe 1532 connected to the middle fuel chamber 1522, and controlling the second valve 1542 installed in the third fuel supply pipe 1533 connected to the outer fuel chamber 1523. 3 may include the step of controlling the valve (1543).

In the chamber fuel control step (S105), when the total fuel flow rate supplied in the total fuel control step (S103) increases, the flow rate of the fuel supplied to the center fuel chamber 1521 is increased and supplied to the middle fuel chamber 1522. The flow rate of the fuel and the flow rate of the fuel supplied to the outer fuel chamber 1523 may be reduced.

Further, in the chamber fuel control step S105, when the total fuel flow rate supplied in the total fuel control step S103 decreases, the flow rate of the fuel supplied to the center fuel chamber 1521 is reduced, and the middle fuel chamber 1522 The flow rate of the fuel supplied to and the fuel flow rate supplied to the outer fuel chamber 1523 may be increased.

As described above, according to the first embodiment, the side nozzle 1500 injects air mixed with fuel into the duct assembly 1280, and the premixed air injected from the side nozzle 1500 is a hot gas inside the duct. Meets and forms a flame. The side nozzle 1500 may increase energy in the hot gas and reduce nitrogen oxides contained in the hot gas.

In addition, according to the first embodiment, a plurality of fuel chambers are installed in the side tube 1510, a fuel supply pipe is individually connected to each fuel chamber, a valve is installed in each fuel supply pipe, and the side control unit 1590 Since the valve is controlled by, the flame of the combustor 1200 can be efficiently controlled by controlling an equivalent ratio of fuel supplied through the side nozzle 1500. Particularly, backfire of the delayed flame LF may be prevented through control of the equivalent ratio, and the delayed flame LF may be further stabilized.

Hereinafter, a gas turbine according to a second embodiment of the present invention will be described. 6 is a cross-sectional view of a side nozzle according to a second embodiment of the present invention cut in the longitudinal direction.

Referring to FIG. 6, since the gas turbine according to the second embodiment has the same structure as the gas turbine according to the first embodiment, except for the structure of the side nozzle, redundant description of the same configuration is omitted. do.

The side nozzle 2500 is installed to pass through the liner 1250 and the flow sleeve 1270 to form a retardation flame inside the duct assembly 1280. The side nozzle 2500 according to the second embodiment includes a side tube 2510 in which fuel and air are mixed, a fuel chamber assembly 2520 installed in the side tube 2510, a first fuel supply pipe 2531, and a second fuel. A supply pipe 2532, a side fuel supply pipe 2535, a first valve 2541, a second valve 2542, a main control valve 2545, and a side control unit 2590 may be included.

The side tube 2510 is made of a substantially circular tube, and the front end of the side tube 2510 may be fixed to the duct assembly 1280. The fuel chamber assembly 2520 includes a plurality of fuel chambers and swirlers installed inside the side tube 2510 to inject fuel. The fuel chamber assembly 2520 may include a center fuel chamber 2521 disposed at the center of the side tube 2510 and a middle fuel chamber 2522 disposed further outside the center fuel chamber 2521.

The center fuel chamber 2521 has a substantially spherical shape, and a first fuel supply pipe 2531 is connected to a rear end of the center fuel chamber 2521. A plurality of injection holes 2521a may be formed in the center fuel chamber 2521.

The middle fuel chamber 2522 may be disposed concentrically with the center fuel chamber 2521. The middle fuel chamber 2522 is formed on the outside of the side tube 2510 and is made of a tube connected in the circumferential direction of the side tube 2510, and the inner wall of the side tube 2510 has a plurality of connected to the middle fuel chamber 2522. The injection hole 2522a may be formed. Accordingly, the middle fuel chamber 2522 can stably inject fuel without interfering with the flow of air.

A first valve 2541 is installed in the first fuel supply pipe 2531 to control a flow rate of fuel moving through the first fuel supply pipe 2531, and a second fuel supply pipe 2532 is provided in the second fuel supply pipe 2532. A second valve 2542 for controlling the flow rate of the fuel moving through may be installed. In addition, the first fuel supply pipe 2531 and the second fuel supply pipe 2532 are connected to the side fuel supply pipe 2535, and a main control valve 2545 may be installed in the side fuel supply pipe 2535. The side fuel supply pipe 2535 supplies fuel to the first fuel supply pipe 2531 and the second fuel supply pipe 2532, and the main control valve 2545 controls the total flow rate of fuel supplied through the side nozzle 2500.

On the other hand, the side control unit 2590 not only controls the total fuel flow rate supplied through the side nozzle 2500, but also controls the flow rate of the fuel supplied through the first fuel supply pipe 2531 and the second fuel supply pipe 2532. .

Hereinafter, a gas turbine according to a third embodiment of the present invention will be described.

7 is a cross-sectional view of a side nozzle according to a third embodiment of the present invention cut in the radial direction, and FIG. 8 is a partial cross-sectional view of a side nozzle according to a third embodiment of the present invention.

7 and 8, the gas turbine according to the third embodiment has the same structure as the gas turbine according to the first embodiment, except for the structure of the side nozzle. Description is omitted.

The side nozzle 3500 according to the second embodiment includes a side tube 3510 in which fuel and air are mixed, a fuel chamber assembly 3520 installed in the side tube 3510, a plurality of fuel supply pipes, and a plurality of valves. I can.

The side tube 3510 is made of a substantially circular tube, and the front end of the side tube 3510 may be fixed to the duct assembly 3280. The fuel chamber assembly 3520 includes a plurality of fuel chambers and swirlers installed inside the side tube 3510 to inject fuel. The fuel chamber assembly 3520 may include a center fuel chamber 3251 disposed at the center of the side tube 3510 and a middle fuel chamber 3522 disposed further outside the center fuel chamber 3251.

The center fuel chamber 3251 is made of a pipe formed in a ring shape, and a first fuel supply pipe 3531 is connected to the center fuel chamber 3251. A plurality of injection holes 3251a may be formed in the center fuel chamber 3251.

The middle fuel chamber 3522 may be disposed concentrically with the center fuel chamber 3251. It may be formed of an annular tube surrounding the center fuel chamber 3251. The second fuel supply pipe 3532 is connected to the middle fuel chamber 3522, and a plurality of injection holes 3522a may be formed in the middle fuel chamber 3522. The center fuel chamber 3251 may have a larger inner diameter than the middle fuel chamber 3522, and the inner diameter D1 of the center fuel chamber 3251 is 1.1 times the inner diameter D2 of the middle fuel chamber 3522 It can be made 1.3 times.

The fuel chamber assembly 3520 may further include a plurality of center swirlers 3524 and a middle swirler 3525. The center swirler 3524 connects the center fuel chamber 3251 and the middle fuel chamber 3522 between the center fuel chamber 3251 and the middle fuel chamber 3522 to guide the flow of air. A plurality of center swirlers 3524 are arranged spaced apart from each other in the circumferential direction of the center fuel chamber 3251. The center swirler 3524 is made of a plate and is disposed to be inclined with respect to the radial direction of the side tube 3510. The center swirler 3524 may be disposed to be inclined so that the clockwise side end is located more rearward than the opposite side end.

The center swirler 3524 may include a passage 3524b connected to the middle fuel chamber 3522 for receiving fuel and an injection hole 3524a through which fuel contained in the passage 3524b is discharged. Accordingly, the center swirler 3524 may receive fuel from the middle fuel chamber 3522 and inject the fuel. When the passage and the injection hole 3524a are formed in the center swirler 3524 as in the second embodiment, fuel can be more evenly mixed with air.

The plurality of middle swirlers 3525 are spaced apart from each other in the circumferential direction of the middle fuel chamber 3522. The middle swirler 3525 is made of a plate and is disposed to be inclined with respect to the radial direction of the side tube 3510. The middle swirler 3525 may be formed to be inclined in different directions from the center swirler 3524.

A first fuel supply pipe 3531 for supplying fuel to the center fuel chamber 3251 is connected to the center fuel chamber 3251, and a first valve may be installed in the first fuel supply pipe 3531. A second fuel supply pipe 3532 for supplying fuel to the middle fuel chamber 3522 may be connected to the middle fuel chamber 3522, and a second valve may be installed in the second fuel supply pipe 3532.

As described above, one embodiment of the present invention has been described, but those of ordinary skill in the relevant technical field add, change, delete or add components within the scope not departing from the spirit of the present invention described in the claims. Various modifications and changes can be made to the present invention by means of the like, and it will be said that this is also included within the scope of the present invention.

1000: gas turbine
1100: compressor
1130: compressor blade
1140: compressor vane
1150: housing
1180: tea room
1200: combustor
1210: combustor casing
1220: burner
1230: nozzle
1240: combustion chamber
1250: liner
1260: transition piece
1270: flow sleeve
1280: duct assembly
1300: main turbine
1500, 2500, 3500: side nozzle
1510, 2510, 3510: side tube
1520, 2520, 3520: fuel chamber assembly
1521, 2521, 3521: center fuel chamber
1522, 2522, 3522: middle fuel chamber
1523: outer fuel chamber
1524, 2524, 3524: Center Whirler
1525, 2525, 3525: Middle Whirler
1526: outer swirler
1531, 2531, 3531: first fuel supply pipe
1532, 2532, 3532: second fuel supply pipe
1533: third fuel supply pipe
1535, 2535: side fuel supply pipe
1541, 2541: first valve
1542, 2542: second valve
1543: third valve
1545, 2545: main control valve
1590, 2590: side control

Claims (20)

A burner having a plurality of main nozzles for injecting fuel and air;
A duct assembly coupled to one side of the burner, the fuel and the air being burned therein, and transferring the burned gas to the turbine; And
A side nozzle disposed downstream of the main nozzle and coupled to an outer peripheral surface of the duct assembly;
Including,
The side nozzle may include a side tube in which fuel and air are mixed, a center fuel chamber for injecting fuel, and a first connected to the center fuel chamber and a middle fuel chamber positioned further outside the center fuel chamber. A combustor comprising a fuel supply pipe and a second fuel supply pipe connected to the middle fuel chamber. The method of claim 1,
A first valve for controlling a flow rate of fuel moving through the first fuel supply pipe is installed in the first fuel supply pipe, and a first valve controlling a flow rate of fuel moving through the second fuel supply pipe is installed in the second fuel supply pipe. Combustor with two valves installed. The method of claim 2,
The middle fuel chamber is made of a tube connected in an annular shape, and a plurality of injection holes are formed in the middle fuel chamber. The method of claim 3,
The center fuel chamber has a spherical shape, and a plurality of injection holes are formed in the center fuel chamber. The method of claim 2,
A combustor having a plurality of center swirlers for guiding the flow of air between the center fuel chamber and the middle fuel chamber. The method of claim 5,
The center swirler is a combustor connected to the middle fuel chamber and including a passage for receiving fuel and an injection hole through which the fuel accommodated in the passage is discharged. The method of claim 5,
The side nozzle is located further outside the middle fuel chamber and further comprises an outer fuel chamber for injecting fuel. The method of claim 7,
A combustor in which a plurality of middle swirlers for guiding the flow of air are formed between the middle fuel chamber and the outer fuel chamber. The method of claim 8,
The center swirler and the middle swirler are inclined in different directions. The method of claim 8,
A plurality of outer swirlers protruding outward are formed in the outer fuel chamber, and the outer swirlers connect the outer fuel chamber and the side tube. The method of claim 7,
A third fuel supply pipe for supplying fuel to the outer fuel chamber is connected to the outer fuel chamber, and a third valve for controlling a flow rate of fuel moving through the third fuel supply pipe is installed in the third fuel supply pipe. The method of claim 2,
The combustor further includes a side control unit for reducing the amount of fuel supplied to the first fuel supply pipe and increasing the amount of fuel supplied to the second fuel supply pipe when the total amount of fuel supplied to the side nozzle decreases. Combustor containing. The method of claim 2,
The combustor further includes a side control unit that increases the amount of fuel supplied to the first fuel supply pipe and decreases the amount of fuel supplied to the second fuel supply pipe when the amount of fuel supplied to the side nozzle increases. Combustor. The method of claim 2,
The middle fuel chamber is formed on the outside of the side tube and consists of a tube connected in a circumferential direction of the side tube, and a plurality of injection holes connected to the middle fuel chamber are formed in the side tube. A burner having a plurality of main nozzles for injecting fuel and air;
A duct assembly coupled to one side of the burner, the fuel and the air being burned therein, and transferring the burned gas to the turbine; And
A side nozzle disposed downstream of the main nozzle and coupled to an outer peripheral surface of the duct assembly;
Including,
The side nozzle may include a side tube in which fuel and air are mixed, a center fuel chamber installed in the side tube and injecting fuel, a middle fuel chamber further outside the center fuel chamber, the center fuel chamber, and the middle fuel A combustor comprising a side control unit for controlling a flow rate of fuel injected from the chamber in inverse proportion. A gas turbine including a compressor for compressing air introduced from the outside, a combustor for combusting by mixing compressed air and fuel compressed by the compressor, and a turbine including a plurality of turbine blades rotating by combustion gases combusted in the combustor As,
The combustor includes a burner having a plurality of main nozzles for injecting fuel and air, a duct assembly that is coupled to one side of the burner, the fuel and the air are burned therein, and delivers the burned gas to the turbine, and the main nozzle It is disposed more downstream and includes a side nozzle coupled to the outer peripheral surface of the duct assembly,
The side nozzle may include a side tube in which fuel and air are mixed and a center fuel chamber installed in the side tube to inject fuel, a middle fuel chamber positioned further outside the center fuel chamber, and a first connected to the center fuel chamber. A gas turbine comprising a fuel supply pipe and a second fuel supply pipe connected to the middle fuel chamber. A main flame generating step of generating a main flame by injecting fuel through a main nozzle coupled to a longitudinal end of the duct assembly;
A delayed flame generating step of generating a delayed flame by injecting fuel through a side nozzle installed on an outer peripheral surface of the duct assembly;
A total fuel control step of adjusting a flow rate of fuel supplied through the side nozzle; And
According to the flow rate supplied to the side nozzle, the flow rate of the fuel supplied to the center fuel chamber located at the center of the side nozzle to inject fuel and the middle fuel chamber located further outside the center fuel chamber to inject fuel is controlled Chamber fuel control step;
Driving method of a combustor comprising a. The method of claim 17,
In the chamber fuel control step, when the fuel flow rate supplied in the total fuel control step increases, the flow rate of the fuel supplied to the center fuel chamber is increased, and the flow rate of the fuel supplied to the middle fuel chamber is decreased. Driving method. The method of claim 17,
In the chamber fuel control step, when the fuel flow rate supplied in the total fuel control step decreases, the flow rate of the fuel supplied to the center fuel chamber is decreased, and the flow rate of the fuel supplied to the middle fuel chamber is increased. Driving method. The method of claim 17,
The chamber fuel control step includes detecting a change in flow rate of the total fuel supplied to the side nozzle, controlling a first valve installed in a first fuel supply pipe connected to the center fuel chamber, and controlling a first valve connected to the middle fuel chamber. A method of driving a combustor comprising the step of controlling a second valve installed in the fuel supply pipe.

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