JPS62102029A - Gas turbine combustion unit - Google Patents

Abstract

PURPOSE:To improve a cooling characteristic at a tail cylinder of a combustion unit by a method wherein a double cylinder structure is composed of a tail cylinder, an outer circumference of the tail cylinder and an inner cylinder of the tail cylinder and the annular part is formed to have a cooling passage communicated with combustion air passage. CONSTITUTION:A gas turbine combustion unit 10 is constructed such that a combustion air passage 17 is formed between an outer cylinder 15 of a linear and an inner cylinder 16, and then a combustion chamber 18 is defined within the inner cylinder 16 of the liner. The tail cylinder 20 is fixed to the rear end part of the inner cylinder. Hot combustion gas is guided into the inner cylinder of the tail cylinder 21 to show a hot gas temperature. However, a double cylinder structure is constructed by the outer cylinder 22 and the inner cylinder 21 for the tail cylinder 20, cooling passage 23 is formed within it and it is accelerated when the cooling air is guided from an injecting chamber into the cooling passage 23. As a result, an efficiency of radiation at the surface of the inner cylinder of the tail cylinder is improved, a rate of thermal conduction at the surface of the inner cylinder of the tail cylinder is made superior and the inner cylinder 21 of the tail cylinder is positively cooled. Therefore, it is possible to decrease the temperature in the tail cylinder 20 less than an allowable temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a gas turbine combustor used in a gas turbine power plant, and more particularly to an improvement in the cold J+ structure of the combustor tail.

[Technical uses of inventions and their problems]

In a gas turbine power generation plant, the discharge air compressed by +1 by the drive of the compressor installed coaxially with the gas turbine is guided to the gas turbine combustor as combustion air, and is combusted into fuel r1 and r6 in the combustor. The combustion gas is guided from the combustor inner cylinder to the gas turbine to drive the gas turbine and do work.

A conventional gas turbine combustor 1 has a receiving structure as shown in FIG. 3, and a plurality of combustors are provided between a compressor 2 and a gas turbine 3.
It is housed in the discharge chamber 4 from the compression 112. The gas turbine combustor 1 includes an outer cylinder 5 and an inner cylinder 6, between which a combustion air passage 7 is formed, and a combustion chamber 8 is formed in the inner cylinder 6.
is defined, and in this combustion chamber 8, fuel is mixed with combustion air and combusted.

Combustion gas resulting from the combustion of fuel v1 passes through the combustor transition pipe 9 and is guided to the inlet of the gas turbine 3.
It is designed to drive and do work.

By the way, the tail YA 9 of the gas turbine combustor 1 fits into the rear end of the inner cylinder and is elastically held by a leaf spring cap, and is compressed 11.
It has a structure in which it is cooled by compressed discharge air. However, in this transition tube cooling structure, convection cooling is mainstream in which the outer surface of the transition tube 9 is cooled by convection of compressor discharge air.
When equipped with a high-temperature gas turbine combustor of ℃ class or higher, the temperature of the transition piece 9 exposed to high-temperature combustion gas exceeds the technically compatible temperature of the transition piece material (approximately 800 degrees Celsius), which reduces the durability of the gas turbine combustor. There was a risk that the quality and reliability of the product would deteriorate.

[Purpose of the invention]

The present invention has been made in consideration of the above-mentioned circumstances, and it improves the cooling performance of the combustor transition piece, and enables gas to maintain sufficient durability and reliability even when applied to high-temperature gas turbines. The purpose is to provide a turbine combustor.

[Summary of the invention]

To achieve the above-mentioned objects, the present invention forms a combustion air flow path between a liner outer cylinder and a liner inner cylinder, defines a combustion chamber within the liner inner cylinder, and includes a tail for guiding combustion gas. In a gas turbine combustor in which a cylinder is provided in the inner cylinder of the liner, the transition piece has a double cylinder structure consisting of an outer cylinder and an inner cylinder, and the annular portion thereof is connected to the combustion air flow path. It is characterized by being formed in a cooling flow path leading to.

[Embodiments of the invention]

Hereinafter, an embodiment of a gas turbine combustor according to the present invention will be described with reference to FIGS. 1 and 2.

A gas turbine combustor 10 according to the present invention is provided between a compressor 11 and a gas turbine 13 that drives a generator 12, and is housed in a chamber casing (not shown) that defines a discharge chamber from the compressor 11. Ru. This one? The chamber casing connects the casings of the compressor 11 and the gas turbine 13 integrally or integrally, and also connects the gas turbine combustor 10 [in the circumferential direction within the chamber casing? ! Two or more pieces, for example 10fl! A or 14 pieces are arranged.

Each gas turbine combustor 101. , is formed into a double cylinder structure from a liner outer cylinder 15 and an inner cylinder 16 constituting the combustor main body, and the annular space thereof is defined as a combustion air flow path 17. A combustion chamber 18 is defined within the liner inner cylinder 16,
There is combustion inside this combustion chamber 18! 1 and combustion air are supplied to cause combustion.

On the other hand, a transition piece 2 is provided at the rear end of the inner cylinder of the gas turbine combustor 10.
0 is installed. The transition tube 20 includes a transition tube inner tube 21 and a transition tube outer tube 2.
2, and an annular space therebetween is defined as a cooling flow path 23. Is there reinforcement in the cold IJI flow path 23? l2
RL1 cold 7J1 fins 24 are arranged in several feathers,
The heat transfer area (heat exchange area) in the cooling channel 23 is increased,
Promote heat dissipation to prevent rust. The transition cylinder inner cylinder 21 is loosely fitted into the rear end of the liner inner cylinder 18 of the combustor main body, and is elastically held by a leaf spring or the like. The inside of the transition tube inner cylinder 21 is formed as a guide path 25 that guides the combustion gas combusted in the combustion chamber 18 to the gas turbine 13 .

One end of the cooling channel 23 formed in the transition piece 20 has an inlet 2.
3a, the outflow side of which is the combustion n1 air flow path 1
7, and guides the cool uj discharge air, which has undergone heat exchange with the combustion gas passing through the transition pipe inner cylinder 21, to the combustion air flow path 17.

In addition, the R section outer cylinder 22 has a large number of cold cylinders as shown in FIG.
The Jl air holes 27 may be provided, for example, in a plurality of rows or randomly in the circumferential direction as required. When a large number of cooling 1 (I) air holes are formed, the axial cross-sectional area of the cooling passage 23 of the transition piece is determined as appropriate based on the cooling performance h10 of the combustor.

Next, the operation of the gas turbine combustor 10 will be explained.

The high-pressure air 11J1 compressed by the drive of the 1F compressor 11 of the gas turbine power generation plant is discharged into the airflow chamber, and a portion of the air from this discharge chamber flows into the cold JJI flow path 2.
3, the remainder is guided to the combustion air flow path 17. The air guided to the combustion air flow path 17 is then passed through the liner inner cylinder 1.
The fuel is introduced into the combustion chamber 18 in the combustion chamber 6, mixed with fuel separately introduced into the combustion chamber 18, and subjected to combustion, resulting in high-temperature combustion gas. This combustion gas is guided to the gas turbine 13 through a guide path 25 formed within the transition piece 0I21. When the combustion gas passes through the gas turbine 13, it expands and does work, driving the generator 12 to rotate. gas turbine 13
The combustion gas that has done work is exhausted.

On the other hand, the inside of the transition tube inner cylinder 21 becomes high temperature because high-temperature combustion gas is guided, but the transition tube 20 is connected to the transition tube outer cylinder 22 and the inner cylinder 21.
It is formed into a double cylinder structure, and a cooling passage 23 is formed inside, and the cooling air is accelerated when guided into the cooling passage 23 from the discharge cylinder, and the flow velocity is, for example, about 10
m/sec to approximately 40 m/sec. As a result, the heat dissipation efficiency of the transition tube inner tube surface is improved, the heat transfer coefficient of the transition tube inner tube surface is improved, and the transition tube inner IFi 121 is actively cooled.

Because of this, cold! Although the i loss increases due to the pressure of the cooling air generated by the Jl flow path 23, the metal temperature of the transition piece 20 can be lowered to below the allowable temperature.

Generally speaking, in order to increase the heat transfer area, the cooling channel 23 is provided with a cold 7. II fins 24 are installed (), and a large number of small holes 27 are installed.
By drilling and impingement cooling, the heat dissipation efficiency of the transition tube inner cylinder surface can be further improved, and even if this gas turbine combustor 10 is applied to a high-temperature gas turbine, the transition tube inner cylinder 21 Humidity can be lowered to a temperature that can be sufficiently withstood by existing combustion materials, for example, to about 700°C.

In one embodiment of the present invention, the liner outer cylinder is extended toward the transition tube side, and the transition tube outer cylinder is inserted into this liner outer cylinder to form an overlapping part. An axial gap may be formed between the liner outer cylinder and the transition cylinder outer cylinder, or the outside of the R cylinder may be integrally or integrally connected to the liner outer cylinder.

〔Effect of the invention〕

As described above, in the gas turbine combustor according to the present invention, the transition piece numbered in the liner inner cylinder is formed into a double-tube structure consisting of the transition cylinder outer cylinder and the transition cylinder inner cylinder, and the annular part thereof is Since the cooling passage is formed in the first cooling passage leading to the combustion air flow passage, when the compressed air discharged into the discharge chitonbum passes through the cooling passage, it is accelerated to improve the heat transfer efficiency and to actively attack the inner cylinder surface of the transition cylinder. Cool u1 in a targeted and effective manner. The compressed air that has cooled the inner cylinder surface of the transition cylinder is guided into the combustion air flow path, so the inner cylinder surface of the transition cylinder is constantly cooled by fresh compressed air for cooling, improving the cooling performance of the combustor tail. Even when this gas turbine combustor is applied to a high-temperature gas turbine, sufficient durability and reliability can be ensured.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of a transition piece structure showing an embodiment of a gas turbine combustor according to the present invention, and FIG. 2 is a partial cross-sectional view of a transition piece structure shown in FIG.
The line view, FIG. 3, is a view showing a gas turbine combustor attached to a gas turbine. 10... Gas turbine combustor, 11... Compressor, 1
3... Gas turbine, 15... Liner outer cylinder, 16
... Liner inner cylinder, 17 ... Combustion air flow path, 18
... Combustion chamber, 20... Transition tube, 21... Transition tube inner tube,
22... Tail tube outer cylinder, 23... Cooling channel, 24...
Cooling fin, 25... Combustion gas guide path, 27...
Cold 7JI air vent. Applicant's agent Hisashi Hatano 2 Zujuku 3 Deputy

Claims (1)

[Scope of Claims] 1. A combustion air flow path is formed between the liner outer cylinder and the liner inner cylinder, a combustion chamber is defined in the liner inner cylinder, and a transition piece for guiding combustion gas is formed as above. In a gas turbine combustor installed in a liner inner cylinder, the transition piece has a double cylinder structure consisting of an outer transition cylinder and an inner cylinder, and its annular portion is connected to a cooling air passageway that communicates with the combustion air flow path. A gas turbine combustor characterized by being formed in a flow path. 2. The gas turbine combustor according to claim 1, wherein a plurality of cooling fins are arranged radially in a cooling passage formed by the transition tube outer cylinder and the transition tube inner cylinder. 3. The gas turbine combustor according to claim 1, wherein the transition tube outer cylinder is provided with a large number of cooling air holes so that the transition tube inner cylinder can be impinged cooled.