JPH08178287A - Burner for gas turbine - Google Patents

Abstract

PURPOSE: To stabilize the combustion at the time of the low load of a gas turbine. CONSTITUTION: The burner for a gas turbine comprises a communicating passage 5 for giving a turning flow of a predetermined direction to a mixture gas from a premixing chamber 1, a hole 6A opened at the passage 5 with a combustion chamber 2, a flame stabilizer 7 so supported as to be able to be inserted into the hole 6A and displaced into the chamber 2, and formed with a cylindrical member, an annular nozzle 8 formed between the hole 6A and the stabilizer 7, and a swirler formed at the outer periphery of the stabilizer 7 to give the turning of a predetermined direction to the mixture gas and separable from the inner periphery of the hole 6A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in gas turbine engine combustors.

[0002]

2. Description of the Related Art A combustor of a gas turbine engine (hereinafter referred to as a gas turbine) is known to have a premixing chamber in order to obtain a uniform air-fuel mixture (JP-A-60-11700).
No. 8).

Explaining this, as shown in FIG. 6, a cylindrical combustion chamber 2 is formed on the inner circumference of a casing 4 via a heat insulating member 3, and an air-fuel mixture is supplied to this combustion chamber 2. A cylindrical premixing chamber 1 and a high-pressure air passage 16 for introducing pressurized air from a heat exchanger (not shown) or a compressor to the premixing chamber 1 are formed.

The pressurized air flowing from the high pressure air passage 16 into the premixing chamber 1 is swirled by the swirler 15 and then mixed with the fuel injected from the main fuel injection valve 10. The premix chamber 1 is arranged substantially parallel to the cylindrical combustion chamber 2, and the premix chamber 1 communicates with the upstream of the combustion chamber 2 via a communication passage 5.

The communication passage 5 has a hole 6 at the base end of the combustion chamber 2.
It is defined by a baffle plate 6 provided with A, and at the base end of the combustion chamber 2, a cylindrical flame stabilizer 7 in which an auxiliary fuel injection valve 9 is housed is substantially coaxial with the combustion chamber 2. And the end portion 7A is inserted into the hole portion 6A formed in the baffle plate 6.

The flame stabilizer 7 is supported by the casing 4 via a guide 17 so as to be displaceable in the axial direction, and an end portion 7A is formed from a hole 6A formed in the baffle plate 6 by a driving means (not shown). It is driven in a direction projecting into the combustion chamber 2.

The outer wall of the flame stabilizer 7 and the hole 6A of the baffle plate 6
An annular nozzle 8 having a predetermined gap is formed between and, and a tapered portion 70 is formed on the outer periphery of the end 7A of the flame stabilizer 7 facing the annular nozzle 8 so as to spread in a tapered shape. , The annular nozzle 8 depending on the axial position of the flame stabilizer 7.
The cross-sectional area of, that is, the flow path cross-sectional area of the air-fuel mixture flowing into the combustion chamber 2 is changed according to the operating load, and the air distribution ratio of the air-fuel mixture blown out from the communication passage 5 to the combustion chamber 2 is changed.

The air-fuel mixture from the premixing chamber 1 is introduced into the combustion chamber 2 from the annular nozzle 8 between the flame stabilizer 7 and the baffle plate 6, and the communication passage 5 burns along the inner circumference of the combustion chamber 2. The air-fuel mixture, which is arranged offset with respect to the axis of the chamber 2 and passes through the communication passage 5, becomes a swirling flow along the inner wall of the combustion chamber 2 with the flame stabilizer 7 as the center, and the flame in the combustion chamber 2 is maintained. A cone-shaped flame starting from the end 7A of the flame device 7 is formed.

Further, after the temperature of the combustion gas is lowered by the air flowing in from the dilution port 12 opened in the dilution cylinder 13, it flows into the turbine (not shown) via the scroll inlet 14.

As such a gas turbine combustor, in addition to the above, ASME PAPER 78-GT-
155 (issued April 9, 1978) is known.

[0011]

By the way, it has been conventionally considered that the stability of combustion in the combustion chamber 2 depends only on the flow velocity of the air-fuel mixture flowing from the annular nozzle 8 into the combustion chamber 2, and therefore at the time of low load. It was considered that the combustion stability could be improved by reducing the cross-sectional area of the annular nozzle 8.

However, in such a conventional gas turbine combustor, the combustion stability is not improved even if the flow velocity discharged from the annular nozzle 8 is increased. As the flow rate of the air-fuel mixture flowing into No. 2 decreases, the swirling of the air-fuel mixture from the communication passage 5 also decreases, so that sufficient flame holding effect may not be obtained and combustion may become unstable. .

Therefore, the present invention has been made in view of the above problems, and in addition to the flow velocity of the air-fuel mixture flowing into the combustion chamber,
An object of the present invention is to provide a combustor of a gas turbine capable of performing stable combustion regardless of load by controlling the swirling of the air-fuel mixture.

[0014]

SUMMARY OF THE INVENTION A first aspect of the present invention is a premixing device that includes a high pressure air passage for introducing pressurized air and a main fuel injection valve to mix pressurized air and fuel from the high pressure air passage. The chamber, the combustion chamber, and the premixing chamber are communicated with each other, and the communication passage that gives a swirling flow in a predetermined direction to the air-fuel mixture, the hole that opens into the combustion chamber, and the hole can be inserted into this hole And,
While being supported displaceably toward the inside of the combustion chamber,
In a gas turbine combustor including a flame stabilizer formed of a tubular member and an annular nozzle formed between the hole and the flame stabilizer, the combustor formed on the outer periphery of the flame stabilizer is mixed. The swirler is provided to swirl in a predetermined direction, and is provided with a swirler capable of coming into contact with and separating from the inner circumference of the hole.

The second aspect of the present invention includes a high pressure air passage for introducing pressurized air, a premixing chamber having a main fuel injection valve for mixing pressurized air and fuel from the high pressure air passage, and combustion. A communication passage that connects the chamber and the premixing chamber, and that imparts a swirling flow in a predetermined direction to the air-fuel mixture, a hole in which the communication passage opens into the combustion chamber, and a combustion chamber that can be inserted into the hole. Is supported so as to be displaceable in the axial direction toward the inside of the flame stabilizer, and is formed of a tubular member, and an outer diameter toward the combustion chamber formed at the end of the flame stabilizer on the combustion chamber side. In a combustor of a gas turbine provided with a tapered portion for enlarging and an annular nozzle formed between the hole portion and the taper portion of the flame stabilizer, a gas mixture formed on the inner circumference of the hole portion A swirl that can swivel in a predetermined direction and can come in contact with and separate from the outer circumference of the taper part of the flame stabilizer. Provided with a door.

A third invention is the first or second invention.
In the invention described above, the swirler is formed of blades arranged at a predetermined interval, and the blades are provided so as to swirl the air-fuel mixture in a direction opposite to the swirling direction in which the communication passage imparts the air-fuel mixture. It is arranged at a predetermined angle.

The fourth invention is the first to third inventions.
In any one of the inventions, the flame stabilizer is provided with means for expanding and contracting according to the load of the gas turbine, and when the load is high, the flame stabilizer is driven to extend toward the combustion chamber and flow through the annular nozzle. While increasing the road cross-sectional area, at low load, the flame stabilizer is driven to contract and the annular nozzle is closed.

[0018]

Therefore, according to the first aspect of the invention, the air-fuel mixture flowing from the high-pressure air passage into the premix chamber is mixed with the fuel from the main fuel injection valve and guided to the communication passage, and the air-fuel mixture is directed in a predetermined direction by the communication passage. Is imparted to the combustion chamber through an annular nozzle between the hole and the flame stabilizer. The flame stabilizer, which can be displaced in the axial direction toward the combustion chamber, is displaced to the most extended position when the gas turbine has a high load to maximize the flow passage cross-sectional area of the annular nozzle between the inner circumference of the hole and the swirler. , While the air-fuel mixture is guided to the combustion chamber in the swirling direction according to the communication passage, at the time of low load the flame stabilizer is contracted and the swirler is brought into contact with the inner circumference of the hole to close the annular nozzle, and the flow passage cross-sectional area is And to swirl the air-fuel mixture according to the swirl direction given by the swirler to guide it to the combustion chamber, increasing the flow velocity of the air-fuel mixture and reliably swirling it at low load when the flow rate decreases. Forms a stable flame with.

In the second aspect of the invention, the air-fuel mixture from the premixing chamber is swirled in a predetermined direction by the communication passage to form a swirling flow, which is formed in the taper portion and the hole of the flame stabilizer. It flows into the combustion chamber through an annular nozzle between the swirler and the swirler. The flame stabilizer, which can be displaced in the axial direction toward the combustion chamber, is displaced to the maximum extension position when the gas turbine is under high load to maximize the flow passage cross-sectional area of the annular nozzle between the outer circumference of the tapered portion and the swirler. , The air-fuel mixture is guided to the combustion chamber in the swirling direction according to the communication passage, while at the time of low load, the flame stabilizer is contracted and the taper part is brought into contact with the inner circumference of the swirler to close the annular nozzle and close the flow path. In addition to reducing the area, the air-fuel mixture is swirled according to the swirling direction given by the swirler and guided to the combustion chamber, and at low load when the flow rate decreases, the flow velocity of the air-fuel mixture is increased and swirling is surely given. This creates a stable flame.

According to the third aspect of the invention, when the annular nozzle is closed, the air-fuel mixture from the communication passage flows into the combustion chamber from between the blades of the swirler, and at this time, it is opposite to the swirling direction given by the communication passage. Each blade imparts swirl to the air mixture in the direction, and at low load with a small flow rate, swirl is reliably imparted while increasing the flow velocity of the mixture to form a stable flame, and a high load that opens the annular nozzle. At times, it is unlikely that the air-fuel mixture swirled by the communication passage will flow between the blades directed in the swirling direction opposite to this swirling direction, so the swirling flow imparted to the communication passage will be disturbed. Instead, it is possible to always form a stable flame.

Further, in the fourth aspect of the invention, since the flame stabilizer is driven to expand and contract according to the load of the gas turbine, the mixture flowing into the combustion chamber is swirled by the communication passage at the time of high load. When the load is low, the swirler imparts a swirl, so that a stable flame can be always formed regardless of load fluctuation.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, a cylindrical combustion chamber 2 is provided on the inner circumference of a casing 4 via a heat insulating member 3, and a cylindrical premixing chamber 1 and a premixing chamber 1 for supplying air-fuel mixture to the combustion chamber 2. High pressure air passages 16 for introducing pressurized air from a heat exchanger (not shown) or the like are formed therein.

The premixing chamber 1 is a swirler 1 arranged on the upstream side.
5, the main fuel injection valve 10 is provided inside, and the downstream side of the premixing chamber 1 communicates with the combustion chamber 2 via the communication passage 5.

The communication passage 5 is arranged offset with respect to the axis of the combustion chamber 2 in order to impart a swirl to the air-fuel mixture along the inner circumference of the combustion chamber 2 in the same manner as in the conventional example shown in FIG. The communication passage 5 is defined by the baffle plate 6 at the base end of the combustion chamber 2, and the communication passage 5 is provided through a hole 6A formed through the baffle plate 6 coaxially with the combustion chamber 2. Communicate with the combustion chamber 2.

The communication passage 5 has a hole 6 at the base end of the combustion chamber 2.
The combustion chamber 2 is defined by a baffle plate 6 having A and a partition wall 50, and a cylindrical flame stabilizer 7 having an auxiliary fuel injection valve 9 accommodated therein is provided at the base end side of the combustion chamber 2. 2, the end 7A of the flame stabilizer 7 on the combustion chamber 2 side is inserted into a hole 6A formed in the baffle plate 6.

The auxiliary fuel injection valve 9 increases the amount of fuel under high load and is selectively driven by a fuel supply means (not shown).

The flame stabilizer 7 is supported by a casing 4 via a guide 17 so as to be displaceable in the axial direction, and the outer wall of the flame stabilizer 7 forms a partition wall 50 defining a communication passage 5 and a seal 18. Through sliding contact.

The flame stabilizer 7 performs relative displacement with respect to the hole 6A by displacement in the axial direction toward the combustion chamber 2.
The flame stabilizer 7 is axially driven by a driving means (not shown).

The drive means expands and contracts the flame stabilizer 7 according to the load of the turbine. As will be described later, the flame stabilizer 7 is driven to the most contracted position when the load is low, while it is driven when the load is high. Then, the flame stabilizer 7 is driven to the most extended position.

Between the flame stabilizer 7 and the hole 6A of the baffle plate 6, an annular nozzle 8 having a predetermined gap corresponding to the axial position of the flame stabilizer 7 is formed. A swirler 20 is formed on the outer wall of the flame stabilizer 7 on the side of the end portion 7 </ b> A facing 8 to expand in a tapered shape toward the combustion chamber 2.

The swirler 20 has an end portion 7 as shown in FIG.
The swirl generating blades 20A are composed of a large number of swirl generating blades 20A arranged at predetermined intervals along the outer wall on the A side.
Is provided so as to project toward the outer circumference of the flame stabilizer 7, and is attached at a predetermined angle θ with respect to the axial direction of the flame stabilizer 7.

The mounting angle θ of the swirl generating blade 20A is
The communication passage 5 is set to a predetermined angle that is opposite to the turning direction of the air-fuel mixture, and for example, the swirl number of the air-fuel mixture passing through the swirler 20 is set to about 0.1 to 1.0.

As shown in FIG. 7, the swirl number is obtained by dividing the axial velocity component Vx and the circumferential velocity component Vθ of the fluid at an arbitrary point a which swirls around the axis at a velocity V. It is expressed by a ratio, and is represented by S = Vθ / Vx where S is the swirl number.

At the most contracted position of the flame stabilizer 7, at least part of the outer circumference of the swirler 20 is formed to have an outer diameter capable of contacting the hole 6A, and at the most contracted position of the flame stabilizer 7, the annular nozzle is provided. Although 8 is closed, the communication passage 5 and the combustion chamber 2 communicate with each other through the space between the swirl generation blades 20A, 20A of the swirler 20, and the air-fuel mixture in the communication passage 5 is transferred to the combustion chamber 2 with the minimum flow passage cross-sectional area. Guide.

On the other hand, at the most extended position of the flame stabilizer 7, the end portion 7A
Is displaced toward the combustion chamber 2 by a predetermined amount, the gap between the swirler 20 and the hole 6A is maximized, and the flow passage cross-sectional area of the annular nozzle 8 is maximized.

An ignition pin 11 is arranged at a predetermined position facing the combustion chamber 2, and a dilution cylinder 13 having a plurality of dilution ports 12 is fitted on the downstream side of the combustion chamber 2 and the dilution port 13 is fitted. Reference numeral 12 communicates with the high pressure air passage 16 to introduce pressurized air for dilution.

The dilution cylinder 13 communicates with a turbine (not shown) through a scroll inlet 14 connected downstream.

With the above construction, the operation will be described.

A part of the pressurized air sent under pressure from a heat exchanger (not shown) is introduced from the high-pressure air passage 16 through the swirler 15 into the premixing chamber 1, where the fuel injected from the main fuel injection valve 10 The mixture is mixed into a mixture, which is guided through the communication passage 5 to form a swirling flow centered on the flame stabilizer 7, and an annular nozzle between the hole 6A of the baffle plate 6 and the flame stabilizer 7. It is introduced from 8 into the combustion chamber 2 while swirling.

The mixture thus introduced into the combustion chamber 2 burns in the combustion chamber 2 while being further mixed with the fuel injected from the auxiliary fuel injection valve 9 under high load, and the dilution port 12 opened in the dilution cylinder 13 After the combustion gas temperature is lowered by the air flowing in from the above, it flows into a turbine (not shown) through the scroll inlet 14 to drive the compressor and the load.

Here, the flow passage cross-sectional area of the annular nozzle 8 is changed according to the load of the turbine, and when the load is medium and high, as shown in FIG. 3, the driving means (not shown) directs the flame stabilizer 7 to the combustion chamber 2. And expand it to form a predetermined gap between the swirler 20 and the hole 6A to increase the flow passage cross-sectional area of the annular nozzle 8, while at the time of low load, as shown in FIG. When the vessel 7 is contracted and driven, the outer periphery of the swirler 20 is the hole 6
The swirl generating blade 2 of the swirler 20 which is displaced to the most contracted position in contact with A, closes the annular nozzle 8 and contacts the hole 6A.
Air-fuel mixture is injected from 0A.

When the flow rate of the air-fuel mixture passing through the annular nozzle 8 is sufficient and the load is high, the air-fuel mixture introduced from the premix chamber 1 passes through the communication passage 5 offset with respect to the axis of the combustion chamber 2. As a result, a swirling flow in a predetermined direction is formed and guided from the annular nozzle 8 to the combustion chamber 2 for combustion.

At this time, the air-fuel mixture flowing from the annular nozzle 8 into the combustion chamber 2 is swirled by the communication passage 5 in the direction opposite to the direction in which the swirl generating blade 20A of the swirler 20 is guided.
Since the flow rate and flow velocity of the air-fuel mixture are large, a sufficient swirl is imparted, and the air-fuel mixture flows into the combustion chamber 2 along the outer periphery of the annular nozzle 8, that is, along the hole 6A, while the air-fuel mixture is opposite to the swirling direction of the communication passage 5. Hardly flows between the swirl generating blades 20A, 20A directed to the air passage, and the inflowing air-fuel mixture is directed in the direction opposite to the swirling direction of the communication passage 5, so that the swirling imparted by the communication passage 5 is caused. The flow can be smoothly introduced into the combustion chamber 2 without disturbing the flow, and a stable flame can be formed.

On the other hand, at the time of low load when the flow rate and flow velocity of the air-fuel mixture in the communication passage 5 decreases, as shown in FIG. 4, the flame stabilizer 7 is driven to the most contracted position and the annular nozzle 8 is closed. From the swirl generation blades 20A of the swirler 20 to the communication passage 5
The air-fuel mixture is guided to the combustion chamber 2.

At this time, in addition to minimizing the flow passage cross-sectional area between the communication passage 5 and the combustion chamber 2, the communication passage 5 is arranged in the direction opposite to the swirling direction which imparts the air-fuel mixture. Due to the swirl generating blade 20A, the air-fuel mixture flowing from the communication passage 5 into the combustion chamber 2 becomes a swirl flow corresponding to the swirl generating blade 20A of the swirler 20, and the flow velocity is increased by the further reduced flow passage cross-sectional area to stabilize the swirl flow. It is possible to form a stable flame and to secure the stability of combustion at low load. Further, at the time of medium and high load, the stability of combustion is maintained by the swirling flow by the communication passage 5 as in the conventional example. Can be improved.

Thus, the flame stabilizer 7 having the swirler 20 formed on the outer periphery is relatively displaced with respect to the rear portion 6A of the baffle plate 6 according to the load of the turbine, and the flow passage cross-sectional area of the annular nozzle 8 is changed to mix. The flow velocity is controlled according to the flow rate of air, and whilst the communication passage 5 swirls the air-fuel mixture during medium and high loads, whilst the swirler 20 swirls during low loads, the swirler 20 swirls the mixed air. Without forming a stable flame, stable combustion can be ensured. Since the swirl generating blade 20A is attached at a predetermined angle θ opposite to the swirling direction of the communication passage 5, swirling at medium and high loads is achieved. The flow is less likely to flow between the swirl generating blades 20A, the swirl flow imparted to the communication passage 5 is not deflected, and the swirl flow according to the load can be efficiently generated. Always To form a stable flame it is possible to improve the stability of the gas turbine.

FIG. 5 shows a second embodiment. The swirler 20 in the first embodiment is a swirler 21 provided on the hole 6A side of the baffle plate 6, and the outer wall of the flame stabilizer 7 on the end 7A side is formed. The tapered portion 70 is formed so as to expand toward the combustion chamber 2, and other configurations are the same as those in the first embodiment.

The swirler 21 has swirl generating blades (not shown) projecting toward the flame stabilizer 7 at a predetermined interval on the inner circumference of the hole 6A, as in the first embodiment, and the swirler 21 of the first embodiment is used. Similar to the swirl generating blade 20A, a predetermined mounting angle θ is set so as to swirl the air-fuel mixture in a direction opposite to the swirl imparting direction of the communication passage 5.

An annular nozzle 8 is formed between the inner circumference of the swirler 21 and the outer wall of the flame stabilizer 7, and the annular nozzle 8 is closed at the most contracted position of the flame stabilizer 7, while Maximize the channel cross-section at the most extended position.

As in the first embodiment, in the turbine,
When the load is high, the flame stabilizer 7 is driven to the most extended position and guides the air-fuel mixture swirled in accordance with the communication passage 5 from the annular nozzle 8 to the combustion chamber 2 to ensure stable combustion, and to swirler 2
1 has swirl generating blades directed in the direction opposite to the swirling direction of the communication passage 5 as in the first embodiment, so that the swirl flow can be disturbed by suppressing the inflow of the air-fuel mixture during medium and high loads. Instead, the flame can be formed smoothly.

On the other hand, when the load of the turbine is low, the flame stabilizer 7 is driven to the most contracted position, the taper portion 70 on the end 7A side is brought into contact with the inner circumference of the swirler 21, and the annular nozzle 8 is closed. By increasing the flow velocity by reducing the flow passage cross-sectional area and imparting the swirl to the air-fuel mixture in the direction opposite to the communication passage 5 by the swirl generating blade (not shown) of the swirler 21, the flow velocity is increased and swirled. To ensure stable combustion even under a low load, and to provide a flame stabilizer 7 depending on the load.
Is relatively displaced with respect to the hole 6A, a flow velocity and swirl according to the flow rate can be imparted to the air-fuel mixture passing through the annular nozzle 8, and combustion can be stabilized regardless of load fluctuations. It becomes.

[0053]

As described above, according to the first aspect of the present invention, the high pressure air passage for introducing the pressurized air and the main fuel injection valve are provided, and the compressed air from the high pressure air passage is mixed with the fuel. A communication passage that connects the mixing chamber, the combustion chamber, and the premixing chamber, and that imparts a swirling flow in a predetermined direction to the mixture, a hole that opens into the combustion chamber, and a communication passage that is inserted into this hole. The flame stabilizer, which is capable of being displaced inwardly of the combustion chamber, is provided with a tubular member, and an annular nozzle formed between the hole and the flame stabilizer. In a combustor of a gas turbine, which is formed on the outer periphery of the flame stabilizer and imparts a swirl in a predetermined direction to the air-fuel mixture, and is equipped with a swirler capable of coming into contact with and separating from the inner periphery of the hole, and the shaft of the flame stabilizer. The swirl direction that changes the flow path cross-sectional area according to the expansion and contraction in the direction It becomes possible to switch, and when the gas turbine has a low load, the flame stabilizer is contracted to bring the swirler into contact with the inner circumference of the hole to close the annular nozzle, which reduces the cross-sectional area of the flow path and the swirl imparted by the swirler. It becomes possible to swirl the air-fuel mixture according to the direction, and at the time of low load when the flow rate decreases, while increasing the flow velocity of the air-fuel mixture and reliably giving swirl, a stable flame is formed and gas It is possible to improve the stability of the turbine.

The second aspect of the present invention includes a high-pressure air passage for introducing pressurized air, a premixing chamber having a main fuel injection valve for mixing pressurized air and fuel from the high-pressure air passage, and a combustion chamber. A communication passage that connects the chamber and the premixing chamber, and that imparts a swirling flow in a predetermined direction to the air-fuel mixture, a hole in which the communication passage opens into the combustion chamber, and a combustion chamber that can be inserted into the hole. Is supported so as to be displaceable in the axial direction toward the inside of the flame stabilizer, and is formed of a tubular member, and an outer diameter toward the combustion chamber formed at the end of the flame stabilizer on the combustion chamber side. In a combustor of a gas turbine provided with a tapered portion for enlarging and an annular nozzle formed between the hole portion and the taper portion of the flame stabilizer, a gas mixture formed on the inner circumference of the hole portion A swirl that can swivel in a predetermined direction and can come in contact with and separate from the outer circumference of the taper part of the flame stabilizer. It is possible to change the flow passage cross-sectional area according to the expansion and contraction of the flame stabilizer in the axial direction, and to switch the swirling direction that gives the air-fuel mixture. By contracting and bringing the tapered part into contact with the inner circumference of the swirler to close the annular nozzle, it is possible to reduce the flow passage cross-sectional area and swirl the air-fuel mixture according to the swirling direction given by the swirler. When the load is low and the flow rate is low, the flow velocity of the air-fuel mixture is increased and the swirl is surely imparted, so that a stable flame is formed and the stability of the gas turbine can be improved.

In the third invention, the swirler is formed of blades arranged at a predetermined interval, and swirls the air-fuel mixture in a direction opposite to the direction in which the communication passage imparts the air-fuel mixture. The blades are arranged at a predetermined angle so that the air-fuel mixture from the communication passages flows into the combustion chamber from between the blades when the annular nozzle is closed, and the communication passages are formed depending on the mounting angle of the blades. By imparting a swirl in the opposite direction, it is possible to surely impart a swirl while increasing the flow velocity of the air-fuel mixture to form a stable flame even when the flow rate is low and the load is low. At high load, the air-fuel mixture does not easily flow between the blades that are directed in the direction opposite to the swirl direction of the communication passage, so it does not disturb the swirl imparted in the communication passage, and the stability of the gas turbine is maintained regardless of the load. Can be improved.

Further, in a fourth aspect of the present invention, the flame stabilizer is provided with means for expanding and contracting according to the load of the gas turbine, and when the load is high, the flame stabilizer is extendedly driven toward the combustion chamber to form an annular shape. While expanding the flow passage cross-sectional area of the nozzle, at low load the flame stabilizer is contracted to close the annular nozzle and the mixture flowing into the combustion chamber is swirled by the communication passage at high load. On the other hand, when the load is low, the swirler imparts a swirl to constantly form a stable flame regardless of the load, thereby improving the stability of the gas turbine.

[Brief description of drawings]

FIG. 1 is a sectional view of a combustor showing an embodiment of the present invention.

FIG. 2 is an enlarged view showing the relationship between the swirler and the annular nozzle.

FIG. 3 is an enlarged view showing the relationship between the swirler and the annular nozzle under medium and high load.

FIG. 4 is an enlarged view showing the relationship between the swirler and the annular nozzle when the load is low.

FIG. 5 is an enlarged cross-sectional view of a flame stabilizer showing a second embodiment.

FIG. 6 is a cross-sectional view of a combustor showing a conventional example.

FIG. 7 is an explanatory diagram showing a swirling flow.

[Explanation of symbols]

 1 premixing chamber 2 combustion chamber 5 communication passage 6 baffle plate 6A hole 7 flame stabilizer 8 annular nozzle 10 main fuel injection valve 16 high pressure air passage 20 swirler 21 swirler 70 taper portion

Claims (4)

[Claims] 1. A high pressure air passage for introducing pressurized air, a premixing chamber having a main fuel injection valve for mixing pressurized air and fuel from the high pressure air passage, a combustion chamber and a premixing chamber. And a communication passage that imparts a swirling flow in a predetermined direction to the air-fuel mixture, a hole in which the communication passage opens to the combustion chamber, and a hole that can be inserted into the hole and is displaced toward the inside of the combustion chamber. In a combustor of a gas turbine, which is supported as much as possible, and which includes a flame stabilizer formed of a tubular member and an annular nozzle formed between the hole and the flame stabilizer, the flame stabilizer A combustor for a gas turbine, wherein the combustor is formed on the outer circumference of the gas turbine to impart a swirl in a predetermined direction to the air-fuel mixture and has a swirler capable of coming into contact with and separating from the inner circumference of the hole. 2. A high pressure air passage for introducing pressurized air, a premixing chamber having a main fuel injection valve for mixing pressurized air and fuel from the high pressure air passage, a combustion chamber and a premixing chamber. And a hole for opening the combustion chamber into the combustion chamber, and a shaft that can be inserted into the hole and that faces the inside of the combustion chamber. A flame stabilizer that is supported so as to be displaceable in the direction, and a taper portion that is formed of a tubular member, and that is formed at the end of the flame stabilizer on the combustion chamber side and that expands the outer diameter toward the combustion chamber. In a combustor of a gas turbine provided with an annular nozzle formed between the hole and the taper of the flame stabilizer, a mixture gas is formed in the inner periphery of the hole and swirls in a predetermined direction in an air-fuel mixture. In addition to providing, it is equipped with a swirler that can contact and separate from the outer circumference of the taper part of the flame stabilizer. Combustor of gas turbine to collect. 3. The swirler is formed of blades arranged at a predetermined interval, and the vanes are arranged so as to swirl the air-fuel mixture in a direction opposite to the swirling direction in which the communication passage imparts the air-fuel mixture. 2. Arranged at a predetermined angle.
Alternatively, the combustor of the gas turbine according to claim 2. 4. The flame stabilizer is provided with means for expanding and contracting according to the load of the gas turbine, and when the load is high, the flame stabilizer is driven to extend toward the combustion chamber to expand the flow passage cross-sectional area of the annular nozzle. 4. The gas turbine combustor according to any one of claims 1 to 3, wherein the flame stabilizer is contractively driven to close the annular nozzle when the load is low.