A branched gas film hole structure of an air-cooled turbine

Abstract

The invention discloses a branch air film hole structure for air cooling turbines. The branch air film hole structure is applicable to air film cooling for cooling hot-end components of gas turbine engines and comprises a plurality of branch air film hole units. The branch air film hole units are arranged on cooled wall surfaces, and each branch air film hole unit comprises a main hole passage anda branch hole passage which obliquely laterally extends out of the middle of a main hole. The branch air film hole structure has the advantages that included angles in expansion directions opposite to flow directions of main flow are formed between the main hole passages and the main flow and between the branch hole passages and the main flow, reverse-kidney-shaped vortex pairs can be formed by two branches of cold air jet flow under entrainment and mutual interference effects of the main flow, accordingly, vortex system structures are favorable for enlarging the transverse cover areas of cold air, hot air can be effectively prevented from being drawn into the lower side from two sides of each cold air film, the adhesive ability of the cold air films can be improved, and air film coolingeffects can be improved; the branch air film hole structure is high in air film cooling efficiency as compared with cylindrical holes and is obviously superior under the condition of high blowing ratios; the branch air film hole structure is mainly cylindrical and has a high practical engineering value, and technologies for processing the branch air film hole structure are simple.

Description

technical field [0001] The invention belongs to the field of cooling of high temperature components such as combustion chambers and turbines, and relates to an air film hole structure, in particular to a branched air film hole structure of an air-cooled turbine, which is mainly applied to the cooling of high temperature components such as combustion chambers and turbines of gas turbines . Background technique [0002] The working temperature of modern gas turbine engines is constantly increasing, which puts forward extremely high requirements on the heat resistance of the materials of the hot end parts. However, it is not enough to improve the heat resistance of materials alone. The high-temperature components such as the box are equipped with a film cooling structure. The film cooling extracts high-pressure cold air from the compressor end, transports it to the hot-end components (such as combustion chambers, turbine blades, casings, etc.) The air film hole is sprayed out,...

AI Technical Summary

Problems solved by technology

However, the shortcoming of the branch-type air film hole structure is that the lateral diffusion ability of the cold air film is insufficient, resulting in a small coverage area of ​​cold air, and the utilization rate of cold air needs to be further improved. In addition, the branch-type air film hole structure is being arranged Limited by its special branch structure, it can only be arranged in a non-staggered way

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