JPH09184630A - Gas turbine combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a maximum flow rate of air supplied to a pre-mixing combustion device to be increased by a method wherein an annular guide ring for use in distributing a part of compressed air to the pre-mixing combustion device is arranged at an inner cylinder near an inlet port of the pre-mixing combustion device. SOLUTION: Compressed air passed through a compressed air feeding passage 5 is distributed into a flow flowing along a concave surface 11 of the annular guide ring 6 and a flow flowing along a projected surface 12 by the annular guide ring 6. The high compressed air flowing along the concave surface 11 is guided to the pre-mixing combustion device and used as pre-mixing combustion air. In this case, the annular guide ring 6 guides forcedly the compressed air to the pre-mixing combustion device 4 without producing any swirl and without peeling off a boundary layer, resulting in that it is possible to increase a maximum flow rate of air.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a gas turbine combustor.

[0002]

2. Description of the Related Art In a gas turbine combustor, a part of a compressed air introduction path is often branched to a premix combustor or the like, and at that time, a large amount of air flow is allowed to flow to the branched premix combustor. Required. Conventionally, a method for increasing the maximum air flow rate that flows into the flow path branched from the compressed air introduction path is to control the internal pressure by providing a pressure adjusting device in the compressed air introduction path, and branch the flow path according to the internal pressure. Methods have been used to vary the flow rate into the. As an example of a measure for controlling the flow rate of compressed air in a flow path having a branch in a gas turbine combustor, Japanese Patent Laid-Open Nos. 58-47927 and 58-140 are known.
520, JP-A-61-96332 and JP-A-61-96333.

[0003]

In a gas turbine combustor having a premixed combustor, a pressure gradient is likely to occur because the air flow direction greatly changes at the point where the compressed air introduction path branches to the premixed combustor. As a result, vortices are generated at the premixed combustor inlet and the bent portion of the premixed combustor, or boundary layer separation occurs. Vortex generation and boundary layer separation must be avoided as they lead to a reduction in the maximum air flow into the premixed combustor.

In the prior art, no consideration was given to suppressing the generation of vortices and separation of the boundary layer, and there was a problem of increasing the energy consumed by the gas turbine combustor.

The present invention according to claims 1, 2, 3, and 4 is
The purpose of the present invention is to increase the maximum air flow rate supplied to the premix combustor by eliminating the occurrence of vortex and boundary layer separation at the premix combustor inlet. Further, it is an object of the present invention to provide an optimum gas turbine combustor for improving the degree of mixing of fuel and air, stabilizing combustion flames, and reducing NOx.

[0006]

In order to achieve the above object, the present invention according to claim 1 provides an annular guide ring in an inner cylinder near the inlet of the premixing combustor.

In order to achieve the above object, the present invention according to claim 2 provides an annular guide ring in the casing near the inlet of the premix combustor in addition to the inner cylinder according to claim 1. Is.

In order to achieve the above object, the present invention according to claim 3 provides an annular guide ring on the outer cylinder near the inlet of the premix combustor in addition to the inner cylinder according to claim 1. It is a thing.

In order to achieve the above object, the present invention according to claim 4 provides an annular guide ring in addition to the inner cylinder and the casing according to claim 2, and also in an outer cylinder near the inlet of the premixing combustor. It is provided.

According to the present invention as set forth in claims 1, 2, 3, and 4,
By providing an annular guide ring on the inner cylinder and / or the casing and / or the outer cylinder near the inlet of the premixed combustor, the air flowing through the compressed air introduction passage flows along the guide ring so that the vortex and the boundary layer are formed. Separation no longer occurs, the resistance due to vortex and boundary layer separation is eliminated and the maximum air flow into the premix combustor can be increased. Furthermore, since there is no dead water region due to vortex and boundary layer separation inside the premixed combustor, the area where compressed air actually flows is increased, the degree of mixing of fuel and air is improved, and combustion flame stabilization and NOx It can be reduced.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The configuration of Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 schematically shows a gas turbine combustor in which the present invention is implemented. The outer cylinder 1 and the inner cylinder 2 are composed of a cylindrical surface and a three-dimensional curved surface, respectively.
Is housed in the casing 3. The premix combustor 4 includes an outer cylinder 1, an inner cylinder 2, and a premix fuel nozzle 9. An annular guide ring 6 formed of a three-dimensional curved surface is arranged on the outer peripheral side of the inner cylinder 2. The compressed air introduction passage 5 is composed of the inner surface of the casing 3 and the outer surface of the outer cylinder 1, and the combustion chamber 7 is composed of the inner surface of the outer cylinder 1 and the inner surface of the inner cylinder 2 and the pilot fuel nozzle 8. Several air holes 10 are formed in the inner cylinder 2 in the circumferential direction.

Next, the operation will be described. The compressed air that has passed through the compressed air introduction passage 5 is caused to flow by the annular guide ring 6 along the concave surface 11 of the annular guide ring 6 and the convex surface 1.
It is distributed to the flow along 2 and. The high-pressure air flowing along the concave surface 11 is guided to the premix combustor and used as premix combustion air. At that time, since the annular guide ring 6 forcibly guides the compressed air to the premixed combustor 4 without generating vortices and separation of the boundary layer, the pressure difference between the compressed air introduction path 5 and the premixed combustor 4 is increased. The maximum air flow rate can be increased as compared with the case where compressed air is introduced into the premixed combustor alone. On the other hand, the high-pressure air flowing along the convex surface 12 flows into the combustion chamber 7 through the air holes 10.

The configuration of the second embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a case where an annular guide ring 13 is attached to the casing 3 in addition to the annular guide ring 6 attached to the inner cylinder 2. The concave surface 11 does not cause vortex generation and separation of the boundary layer, and the premixing combustor 4
The operation of introducing the compressed air to is the same as that of the first embodiment. In the second embodiment, the convex surface 12 of the annular guide ring 6 attached to the casing and the annular guide ring 13 eliminate the generation of vortex of the compressed air passing through the air hole 10 and the separation of the boundary layer. Will be easier than.

The configuration of the third embodiment of the present invention will be described with reference to FIG. FIG. 3 shows a case where an annular guide ring 14 is attached to the outer cylinder 1 in addition to the annular guide ring 6 attached to the inner cylinder 2. Annular guide ring 1
The operation in which the compressed air is guided to the premixed combustor 4 without the generation of vortices and separation of the boundary layer is performed by the annular guide ring 6
The concave surface 11 is the same as the concave surface 11. In the third embodiment, since the annular guide ring 14 assists the operation of the concave surface 11, it becomes easier to increase the maximum compressed air flow rate flowing into the premix combustor 4 than in the first embodiment.

[0015]

According to the present invention as set forth in claim 1, by attaching the annular guide ring to the inner cylinder, the compressed air passing through the compressed air introduction passage is allowed to flow along the concave surface and the convex surface of the annular guide ring. The airflow streamline is divided into two parts, and the airflow line has a curvature, which makes it easier to bend when the air flows from the compressed air introduction path to the premix combustor, and the maximum flow rate of the air flowing in the premix combustor is To increase. In addition, it prevents vortex generation and boundary layer separation and reduces pressure loss at the premix combustor inlet.

According to the present invention as set forth in claim 2, in addition to the effect of the present invention as set forth in claim 1, by attaching the annular guide ring to the inner cylinder and the casing, the annular guide ring installed in the inner cylinder is provided. Since compressed air flows along the flow path formed by the convex surface and the annular guide ring installed in the casing, the pressure loss of the air flow flowing into the combustion chamber via the air holes is reduced.

According to the present invention as set forth in claim 3, the effect of the present invention as set forth in claim 1 can be further enhanced by attaching the annular guide rings to the inner cylinder and the outer cylinder.

According to the invention of claim 4, the effect of the invention of claim 2 can be further enhanced by attaching the annular guide ring to the inner cylinder, the casing and the outer cylinder.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a gas turbine combustor of Example 1 in which an annular guide ring is attached to an inner cylinder.

FIG. 2 is a partial cross-sectional view of the gas turbine combustor of Example 2 in which an annular guide ring is attached to an inner cylinder and a casing.

FIG. 3 is a partial cross-sectional view of a gas turbine combustor of Example 3 in which annular guide rings are attached to an inner cylinder and an outer cylinder.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outer cylinder, 2 ... Inner cylinder, 3 ... Casing, 4 ... Premix combustor, 5 ... Compressed air introduction path, 6 ... Annular guide ring, 7 ...
Combustion chamber, 8 ... Pilot fuel nozzle, 9 ... Premix fuel nozzle, 10 ... Air hole, 11 ... Concave surface of annular guide ring,
12 ... Convex surface of annular guide ring.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Noriyuki Hayashi, Inventor Noriyuki Hayashi, 7-2-1, Omika-cho, Hitachi-shi, Ibaraki Hitachi, Ltd. Electric Power & Electric Development Headquarters 7-2-1, Hitachi Ltd. Electric Power & Electric Development Headquarters (72) Inventor Shigeyoshi Kobayashi 7-2-1, Omika-cho, Hitachi City, Ibaraki Hitachi Electric Power & Electric Development Headquarters

Claims (4)

[Claims] 1. A gas turbine combustor having a premixed combustor formed of an outer cylinder and an inner cylinder inside a casing,
An annular guide ring that distributes a part of the compressed air flowing in through a compressed air introduction passage formed by the casing and the outer cylinder to the premixed combustor is provided near the inlet of the premixed combustor. A gas turbine combustor provided in an inner cylinder. 2. The gas turbine combustor according to claim 1, wherein the annular guide ring is also provided in the casing near an inlet of the premix combustor. 3. The gas turbine combustor according to claim 1, wherein the annular guide ring is also provided in the outer cylinder near the inlet of the premixing combustor. 4. The gas turbine combustor according to claim 2, wherein the annular guide ring is also provided in the outer cylinder near the inlet of the premix combustor.