CN-121993269-A - Exhaust gas line and gas turbine plant

CN121993269ACN 121993269 ACN121993269 ACN 121993269ACN-121993269-A

Abstract

The present disclosure provides an exhaust duct and a gas turbine plant that suppress damage to a member provided on the downstream side of the axis of the exhaust duct caused by extraction air discharged into the exhaust duct. The exhaust duct includes a duct body through which exhaust gas from the gas turbine can flow, and an extraction air introduction pipe through which compressed air, i.e., extraction air extracted from a compressor of the gas turbine, can be introduced into the duct body. The suction inlet pipe has an outlet capable of discharging the suction air into the pipe body, and a pipe inner pipe portion that exists in the pipe body. The pipe inner pipe portion is cylindrical about a pipe axis inclined with respect to the rotor axis so as to extend gradually radially inward with respect to the rotor axis toward the axis downstream side. The outlet is opened at an end of the pipe inner pipe portion on the outlet side in the pipe axial direction so that the extraction air can be discharged to the outlet side in the pipe axial direction in which the pipe axis extends.

Inventors

TSUMURA YOSHIMASA
Tian Bianyou
Awai Kentaro
ITO TAKANORI
Takei Kako
Plumage field is great flat
ONISHI EIJI
TAKATA TOMOSHIGE
Ping Gangxian
AOTA TOYOMASA

Assignees

三菱重工业株式会社

Dates

Publication Date: 20260508
Application Date: 20251028
Priority Date: 20241101

Claims (10)

1. An exhaust gas conduit, wherein, The exhaust duct includes: a duct body through which exhaust gas from a gas turbine having a gas turbine rotor rotatable about a rotor axis is circulated, and An extraction air introduction pipe capable of introducing compressed air extracted from a compressor of the gas turbine, that is, extraction air, into the duct main body, The duct body is tubular about the rotor axis, is connected to the gas turbine so as to allow the exhaust gas from the gas turbine to flow in, with respect to the gas turbine, an axis upstream side of the gas flowing in the gas turbine and the duct body and the axis downstream side of the gas flowing in the gas turbine and the duct body in an axis direction along which the rotor axis extends, The suction inlet pipe is provided with: An inlet into which the extraction air can flow; An outlet capable of discharging the extraction air into the duct body, and A pipe inner pipe portion which exists in the pipe main body, The pipe inner pipe portion is cylindrical around a pipe axis inclined with respect to the rotor axis so as to extend gradually radially inward with respect to the rotor axis toward the axis downstream side, The outlet is opened at an end of the pipe inner pipe portion on the outlet side so as to be capable of discharging the extraction air to the outlet side of the inlet sides on the side close to the rotor axis, that is, the outlet side and the opposite side in the pipe axis direction in which the pipe axis extends.
2. The exhaust duct of claim 1, wherein, The opening face of the outlet in the pipe inner pipe portion faces in a direction having a component on the downstream side of the axis.
3. The exhaust duct of claim 1, wherein, An edge on the axis downstream side of the outlet in the pipe inner portion is located further radially outward with respect to the rotor axis than an edge on the axis upstream side of the outlet.
4. The exhaust duct of claim 1, wherein, The ratio of the length of the generatrix, which is the edge on the axis downstream side of the generatrix in the outer peripheral surface of the pipe inner tube portion, to the length of the generatrix, which is the edge on the axis upstream side of the generatrix in the outer peripheral surface of the pipe inner tube portion, is 0.35 or more and 0.45 or less.
5. The exhaust duct of claim 1, wherein, The pipe inner pipe portion is formed so that a passage area becomes gradually larger as going toward the outlet side.
6. The exhaust duct of claim 1, wherein, The air exhaust ingress pipe is provided with a pipe outer pipe part which exists outside the pipe main body and is connected with the pipe inner pipe part, The inlet is open at an end of the pipe outer pipe portion on the inlet side.
7. The exhaust duct of claim 6, wherein, The exhaust pipe is provided with a sleeve which is arranged outside the pipe main body and is cylindrical around the pipe axis on the outer peripheral side of the pipe outer pipe part, The outer pipe part of the pipeline takes a shape of a cylinder around the axis of the pipeline, The inlet side end of the sleeve is connected to the pipe outer tube, The outlet-side end of the sleeve is connected to the pipe body.
8. The exhaust duct of claim 1, wherein, An extension line of the pipe axis toward the outlet side intersects the pipe body.
9. The exhaust duct of claim 8, wherein, The rigidity of an air collision region, which is a region of the duct body intersecting the extension line, is higher than the rigidity of a region of the duct body symmetrical to the air collision region with respect to the rotor axis.
10. A gas turbine plant, wherein, The gas turbine plant is provided with: The exhaust duct of any one of claims 1 to 9; the gas turbine, and And an extraction pipe that can guide the extraction air extracted from the compressor of the gas turbine to the extraction introduction pipe.

Description

Exhaust gas line and gas turbine plant Technical Field The present disclosure relates to an exhaust duct through which exhaust gas can flow from a gas turbine, and a gas turbine plant provided with the exhaust duct. The present application claims priority to japanese patent application No. 2024-193071 based on month 1 of 2024, 11, and this content is incorporated herein. Background The gas turbine plant is provided with a gas turbine and an exhaust duct. The gas turbine has a compressor capable of compressing air to generate compressed air, a combustor capable of combusting fuel in the compressed air to generate combustion gas, and a turbine capable of being driven by the combustion gas. The compressor has a compressor rotor rotatable about a rotor axis, and a compressor housing covering the compressor rotor. The turbine has a turbine rotor rotatable about a rotor axis, and a turbine housing covering the turbine rotor. The turbine is disposed on an axial downstream side of the compressor from among an axial upstream side and an axial downstream side in an axial direction in which the rotor axis extends. The compressor rotor and the turbine rotor are interconnected to form a gas turbine rotor. The exhaust duct is disposed on the downstream side of the axis of the turbine and connected to the turbine casing. The exhaust gas, which is the combustion gas discharged from the turbine, flows into the exhaust pipe. An exhaust heat recovery boiler that generates steam by using heat of exhaust gas is provided on the axis downstream side of the exhaust duct, for example. Patent document 1 below discloses a gas turbine plant including a gas turbine and an exhaust duct. Patent document 1 describes a technique in which, in order to improve the starting characteristics of a gas turbine, a part of compressed air compressed by a compressor of the gas turbine is extracted from the gas turbine, and the compressed air is introduced into an exhaust duct as extraction air. The exhaust duct includes a duct body through which exhaust gas from the gas turbine can flow, and an extraction air introduction duct through which extraction air from the compressor can be introduced into the duct body. The compressor is connected with the air suction ingress pipe through an air suction pipe. The suction inlet pipe has a pipe outer pipe portion that exists outside the pipe body, and a pipe inner pipe portion that exists inside the pipe body. The duct outer tube portion extends from the duct body in a direction of a component radially outward relative to the rotor axis. An inlet through which the extraction air can flow is formed at the end of the outer pipe portion of the duct. The pipe inner pipe portion has a radially extending portion extending from the pipe main body in a direction having a component radially inward of the rotor axis, and an axially extending portion extending from a radially inward end of the radially extending portion toward the axially downstream side. The radially inner end of the radially extending portion of the inner pipe portion is connected to the outer pipe portion. An outlet through which the extraction air can be discharged into the duct body is formed at an end portion of the duct inner tube portion on the downstream side of the axis-direction extending portion. Therefore, the extraction air from the compressor is discharged from the outlet of the extraction air introduction pipe toward the axis downstream side. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2012-177306 In the exhaust duct described in patent document 1, since the extraction air is discharged from the extraction air introduction pipe toward the downstream side of the axis, for example, if the exhaust heat recovery boiler is provided on the downstream side of the axis of the exhaust duct as described above, there is a possibility that the heat transfer pipe or the like of the exhaust heat recovery boiler may be damaged by the extraction air. Disclosure of Invention Problems to be solved by the invention Accordingly, an object of the present disclosure is to provide a technique capable of suppressing damage to a member provided on the downstream side of the axis of an exhaust duct due to extraction air discharged into the exhaust duct. Means for solving the problems An exhaust duct as one means for achieving the above object is provided with a duct body through which exhaust gas from a gas turbine having a gas turbine rotor rotatable about a rotor axis can flow, and an extraction air introduction duct through which compressed air, i.e., extraction air extracted from a compressor of the gas turbine, can be introduced into the duct body. The duct body is tubular about the rotor axis, and is connected to the gas turbine at an axis upstream side of the gas turbine in an axis direction extending along the rotor axis and along which the gas flows, and at the axis downstream side of the gas turbine