KR-20260065520-A - EXHAUST DUCT AND GAS TURBINE PLANT

KR20260065520AKR 20260065520 AKR20260065520 AKR 20260065520AKR-20260065520-A

Abstract

The exhaust duct comprises a duct body through which exhaust gas from a gas turbine can flow, and a purge inlet pipe capable of introducing purge air, which is compressed air extracted from a compressor of the gas turbine, into the duct body. The purge inlet pipe has an outlet capable of discharging the purge air into the duct body and an inner duct section present within the duct body. The inner duct section forms a tubular shape around a pipe axis inclined with respect to the rotor axis so as to gradually extend inward in the diameter direction with respect to the rotor axis as it faces downstream of the axis. The outlet is opened at the end of the inner duct section on the outlet side so as to be able to discharge the purge air toward the outlet side in the direction of the pipe axis where the pipe axis extends.

Inventors

츠무라 요시마사
다나베 유
마치이 고타로
이토 다카노리
다케이 요시코
하타노 고헤이
고니시 에이지
다카타 도모시게
히라오카 사토시
아오타 도요세이

Assignees

미츠비시 파워 가부시키가이샤

Dates

Publication Date: 20260508
Application Date: 20251022
Priority Date: 20241101

Claims (10)

A duct body through which exhaust gas from a gas turbine having a gas turbine rotor rotatable about the rotor axis can flow, and The system is equipped with an exhaust inlet pipe capable of introducing exhaust air, which is compressed air extracted from the compressor of the gas turbine, into the duct body. The above duct body forms a tubular shape around the rotor axis and is connected to the downstream side of the axis where gas flows out of the gas turbine and the duct body, in the direction of the axis where the rotor axis extends, so that the exhaust gas from the gas turbine can flow in. The above-mentioned additional inlet tube is, The above-mentioned inlet through which exhaust air can be introduced, and An outlet capable of discharging the above-mentioned exhaust air into the duct body, and It has an inner duct section existing within the above-mentioned duct body, and The above-mentioned duct inner section forms a tubular shape around a tube axis inclined with respect to the rotor axis, such that it gradually extends inward in the diameter direction with respect to the rotor axis as it faces downstream of the axis. The above outlet is opened at the end of the outlet side of the inner tube of the duct so as to enable the exhaust air to be discharged toward the outlet side, which is the side closer to the rotor axis in the direction of the pipe axis where the pipe axis extends, and the opposite side, which is the inlet side. Exhaust duct.
In Article 1, The opening surface of the outlet in the inner part of the duct is oriented toward the direction having a component on the downstream side of the axis. Exhaust duct.
In Article 1, The edge of the outlet on the axis downstream side in the inner duct section is located radially outward with respect to the rotor axis compared to the edge of the outlet on the axis upstream side. Exhaust duct.
In Article 1, As a busbar on the outer surface of the inner pipe portion of the above duct, the ratio of the length of the busbar on the edge downstream of the axis to the length of the busbar on the edge upstream of the axis is 0.35 or more and 0.45 or less. Exhaust duct.
In Article 1, The inner part of the duct is formed such that the passage area gradually increases as it faces the outlet side. Exhaust duct.
In Article 1, The above-mentioned exhaust inlet pipe is located outside the duct body and has an outer duct section connected to the inner duct section, The above inlet is opened at the end of the inlet side of the outer part of the above duct. Exhaust duct.
In Article 6, It is provided with an outer shell tube that exists outside the duct body and forms a tubular shape around the pipe axis on the outer circumference side of the duct exterior part, The outer part of the above duct forms a tubular shape around the pipe axis, and The end of the inlet side of the above outer shell tube is connected to the outer part of the above duct, and The end of the outlet side of the above outer casing is connected to the above duct body. Exhaust duct.
In Article 1, The extension line of the above pipe axis toward the outlet side intersects the above duct body Exhaust duct.
In Article 8, Among the above duct body, the air collision region, which is the area intersecting the extension line, has higher rigidity than the area within the duct body that is symmetrical to the air collision region with respect to the rotor axis. Exhaust duct.
The exhaust duct described in any one of claims 1 to 9, and The above gas turbine and, A extraction pipe capable of leading the extraction air extracted from the compressor of the gas turbine to the extraction inlet pipe. Gas turbine plant.

Description

Exhaust Duct and Gas Turbine Plant The present disclosure relates to an exhaust duct through which exhaust gas from a gas turbine can flow, and a gas turbine plant having said exhaust duct. The present invention claims priority based on Japanese Patent Application No. 2024-193071 filed in Japan on November 1, 2024, and incorporates the contents thereof into this specification. A gas turbine plant is equipped with a gas turbine and an exhaust duct. The gas turbine has a compressor capable of compressing air to produce compressed air, a combustor capable of burning fuel in the compressed air to produce combustion gas, and a turbine capable of being driven by the combustion gas. The compressor has a compressor rotor capable of rotating about the rotor axis and a compressor casing covering the compressor rotor. The turbine has a turbine rotor capable of rotating about the rotor axis and a turbine casing covering the turbine rotor. The turbine is positioned downstream of the compressor axis, between the upstream and downstream sides along the axis direction in which the rotor axis extends. The compressor rotor and the turbine rotor are connected to each other to form a gas turbine rotor. The exhaust duct is positioned downstream of the turbine axis and is connected to the turbine casing. Exhaust gas, which is combustion gas exhausted from the turbine, flows into this exhaust duct. Downstream of the exhaust duct axis, for example, a heat recovery boiler is provided to generate steam using the heat of the exhaust gas. Patent Document 1 below discloses a gas turbine plant equipped with a gas turbine and an exhaust duct. Patent Document 1 describes a technique for improving the starting characteristics of a gas turbine by extracting a portion of the compressed air compressed by the gas turbine's compressor from the gas turbine and introducing this compressed air into the exhaust duct as the extracted air. The exhaust duct is equipped with a duct body through which exhaust gas from the gas turbine can flow, and an extraction inlet pipe through which the extracted air from the compressor can be introduced into the duct body. The compressor and the extraction inlet pipe are connected by an extraction pipe. The exhaust inlet pipe comprises an outer duct section located outside the duct body and an inner duct section located inside the duct body. The outer duct section extends from the duct body in a direction having a radially outer component with respect to the rotor axis. An inlet is formed at the end of this outer duct section to allow exhaust air to flow in. The inner duct section comprises a radially extended section extending from the duct body in a direction having a radially inner component with respect to the rotor axis, and an axially extended section extending from the radially inner end of this radially extended section toward the axis downstream. The radially inner end of the radially extended section of the inner duct section is connected to the outer duct section. An outlet is formed at the axially downstream end of the axially extended section of the inner duct section to allow exhaust air to be discharged into the duct body. Accordingly, exhaust air from the compressor is exhausted toward the axis downstream from the outlet of the exhaust inlet pipe. FIG. 1 is a schematic diagram of a gas turbine plant in one embodiment according to the present disclosure. FIG. 2 is an overall cross-sectional view of an exhaust duct in a first embodiment according to the present disclosure. FIG. 3 is a cross-sectional view of a key part of an exhaust duct in a first embodiment according to the present disclosure. FIG. 4 is a cross-sectional view of a key part of an exhaust duct in a first comparative example according to the present disclosure. FIG. 5 is a cross-sectional view of a key part of an exhaust duct in a second comparative example according to the present disclosure. FIG. 6 is a cross-sectional view of a key part of an exhaust duct in a second embodiment according to the present disclosure. FIG. 7 is a cross-sectional view of a key part of an exhaust duct in a third embodiment according to the present disclosure. Hereinafter, various embodiments of an exhaust duct and a gas turbine plant equipped with said exhaust duct according to the present disclosure will be described using the drawings. One embodiment of a gas turbine plant Hereinafter, an embodiment of a gas turbine plant according to the present embodiment will be described with reference to FIG. 1. The gas turbine plant in this embodiment is equipped with a gas turbine (GT), a extraction pipe (5), a heat utilization facility (20), and an exhaust duct (30). A gas turbine (GT) comprises a compressor (10) capable of compressing air (A) to produce compressed air, a plurality of combustors (15) capable of burning fuel (F) in the compressed air to produce combustion gas, an intake casing (13), an intermediate casing (16), and a turbine (17) capable of being