DE-112017002810-B4 - Cooling structure for a gas turbine engine

Abstract

Gas turbine engine cooling structure for cooling a component (5) of a gas turbine engine using a working gas of the gas turbine engine as a cooling medium, wherein the gas turbine engine cooling structure comprises: a passage wall (13) formed by a part of the component (5) and facing a cooling medium passage (19) through which the cooling medium flows; and several heat transfer improvement ribs projecting from a wall surface of the passage wall (13) and having W-shapes, each heat transfer improvement rib (15) having adjacent corner wall areas designed to project alternately towards an upstream side and a downstream side in the direction of flow of the cooling medium, wherein an outer corner region of each heat transfer improvement rib (15) facing the upstream side is formed in an angled shape, and an inner corner area of each heat transfer improvement rib (15) facing the upstream side is formed in a curved shape.

Inventors

• Tomoko Tsuru
• Katsuhiko Ishida
• Yuwa Kawahara

Assignees

• KAWASAKI JUKOGYO KABUSHIKI KAISHA

Dates

Publication Date

20260513

Application Date

20170530

Priority Date

20160601

Claims (6)

1. Gas turbine engine cooling structure for cooling a component (5) of a gas turbine engine using a working gas of the gas turbine engine as a cooling medium, wherein the gas turbine engine cooling structure comprises: a passage wall (13) formed by a part of the component (5) and facing a cooling medium passage (19) through which the cooling medium flows; and several heat transfer improvement ribs projecting from a wall surface of the passage wall (13) and having W-shapes, each heat transfer improvement rib (15) having adjacent corner wall regions configured to project alternately towards an upstream side and a downstream side in the direction of flow of the cooling medium, whereby an outer corner region of each heat transfer improvement rib (15) facing the upstream side is angled, and an inner corner region of each heat transfer improvement rib (15) facing the upstream side is curved.
2. Gas turbine engine cooling structure according to Claim 1 , in which the several heat transfer improvement ribs (17) are arranged such that the upstream corner wall regions and the downstream corner wall regions of the heat transfer improvement ribs (15) are each aligned at identical positions with respect to a transverse direction of the cooling medium passage (19), an inner corner region of each heat transfer improvement rib (15) facing downstream is formed in a curved shape, an outer corner region of each heat transfer improvement rib (15) facing downstream is formed in an angled shape, and a radius of curvature of the upstream the radius of curvature of the inner corner area facing the downstream side is equal to the distance between the adjacent heat transfer improvement ribs (15).
3. Gas turbine engine cooling structure according to Claim 1 , in which an outer corner area facing the downstream side and an inner corner area facing the downstream side are all formed in a curved shape.
4. Gas turbine engine cooling structure according to one of the Claims 1 until 3 , in which the component is a burner jacket (5) of cylindrical shape, which forms a combustion chamber of a burner, and the cooling medium passage (19) is a supply passage for a working gas, which is formed between the burner jacket (5) and a housing of the burner.
5. Method for manufacturing the multiple heat transfer improvement fins (17) in the cooling structure according to one of the Claims 1 until 4 , wherein the method comprises the following step: producing a W-shaped groove by cutting the wall surface of the passage wall (13) of the component (5) once or several times along a path with a predetermined W-shape using a cutting tool designed for cutting by means of a blade provided on an outer circumferential surface of a column-shaped rotating body.
6. Method for manufacturing the multiple heat transfer improvement fins (17) in the cooling structure according to Claim 2 , wherein the method comprises: producing a W-shaped groove by a single cutting of the wall surface along a path with a predetermined W-shape using a cutting tool having a machining diameter corresponding to the distance between the adjacent heat transfer improvement ribs (15) and designed for cutting by means of a blade provided on an outer circumferential surface of a column-shaped rotating body.

Description

Background of the invention (Field of invention) The present invention relates to a structure for cooling a gas turbine engine. (Description of the state of the art) In recent years, it has become desirable in gas turbine engines to increase the amount of combustion air to prevent an increase in flame temperature and thus the formation of NOx due to high-temperature combustion. Accordingly, to reduce the amount of air (cooling air) that does not contribute to the combustion itself, efforts have been made to improve the convection cooling performance of the burner jacket. For example, the following cooling structures for a burner jacket are known: a structure in which V-shaped heat transfer improvement fins are arranged on the outer circumferential surface of a burner jacket (see patent document 1), and a structure in which W-shaped heat transfer improvement fins are formed continuously on the outer circumferential surface of a burner jacket. Since an outer corner area of a side surface on the upstream side of the fin has an angular shape, when fins with such a shape are used, compressed air collides with the heat transfer improvement fin to effectively create a vortex flow, thereby promoting the cooling of the outer circumferential surface of the burner jacket. [State of the art documents] [Patent document] Patent documents] The Japanese patent publication JP 2006 – 63 984 A Disclosing a combustion chamber lining for a gas turbine, consisting of a body with a plurality of inclined strips on an outer surface of the combustion chamber lining. A plurality of the inclined strips are arranged in an array around the outer surface. Gaps are arranged between the plurality of inclined strips to form a vortex in the cooling air flowing longitudinally along the outer surface of the combustion chamber lining. Out of JP 2007 - 132 640 A A gas turbine combustion chamber is known that is equipped with an air cooling recovery structure designed to reuse the air used for cooling the combustion chamber as combustion air. It comprises a soundproof lining formed between the outer wall surface of a combustion chamber burner tube and a cover element. This generates a cooling airflow at an annular passage. Out of DE 199 63 373 A1 A cooling device for a flow channel wall surrounding a flow channel is known. JP 2006 - 100 293 A refers to a cooling fin and a cooling structure where the heat dissipation properties in a heat transfer surface are improved by protrusions. Overview of the invention However, heat transfer improvement fins designed as continuous W-shapes have a reliability issue. This is because, generally, a burner jacket experiences high thermal stress due to the temperature difference between the inside and outside. Furthermore, a constant pressure differential between the inside and outside exerts a pressure load on the inside during operation. Therefore, heat transfer improvement fins with angled outer or inner corners, such as a V-shape or a W-shape, are likely to crack due to the stress concentration at the angled section. The object of the present invention is to create a gas turbine engine cooling structure with excellent cooling performance and high reliability in order to solve the aforementioned problem. To solve the aforementioned problem, a gas turbine engine cooling structure according to the present invention is a structure for cooling a component of a gas turbine engine using a working gas of the gas turbine engine as a cooling medium, wherein the gas turbine engine cooling structure comprises: a through-wall formed by a part of the component and facing a cooling medium passage through which the cooling medium flows; and Several heat transfer improvement ribs projecting from a wall surface of the passage wall and having W-shapes, each heat transfer improvement rib having adjacent corner wall areas configured to project alternately towards an upstream side and a downstream side in the direction of flow of the cooling medium, with one facing the upstream side The outer corner region of each heat transfer improvement rib is formed in an angled shape, and an inner corner region facing the upstream side and/or an outer corner region facing the downstream side and/or an inner corner region facing the downstream side of each heat transfer improvement rib is formed in a curved shape. The inner corner area facing upstream, the outer corner area facing downstream, and the inner corner area facing downstream can all be formed in a curved shape. According to the present configuration, the outer corner areas facing upstream, which directly collide with the cooling medium and are areas with a high heat transfer rate, remain angular, thus preserving the cooling effect of the heat transfer enhancement fin group. Meanwhile, the other outer corner areas and the inner corner areas, which have comparatively low heat transfer rates and therefore less impact on the cooling effect, are curved. This reduces the load concentration