CN-122014360-A - Double-layer composite sealing structure of turbine blade of aero-engine

CN122014360ACN 122014360 ACN122014360 ACN 122014360ACN-122014360-A

Abstract

The application discloses a double-layer composite sealing structure of a turbine blade of an aeroengine, which belongs to the technical field of sealing of hot end components of the aeroengine and comprises sealing sheets, wherein mounting grooves are respectively formed in the opposite inner sides of two adjacent turbine blade edge plates, two ends of each sealing sheet are respectively inserted into two adjacent mounting grooves, each sealing sheet comprises a metal functional layer and a ceramic fiber functional layer, and the ceramic fiber functional layer is positioned on one side, close to a gas flow G, of each metal functional layer. The application overcomes the contradiction between the temperature resistance and the elastic capability of a single material through the cooperative design of the material and the configuration, realizes stable and reliable long-life sealing under the ultra-high temperature environment, and remarkably improves the efficiency and the reliability of the engine.

Inventors

LUO XIANG
ZHANG YOUYAO
FANG HONGYI
LIU DONGDONG
WANG LEI
WU LEI

Assignees

北京航空航天大学
中国航发四川燃气涡轮研究院

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (8)

1. The double-layer composite sealing structure of the turbine blade of the aeroengine is characterized by comprising sealing sheets (1), wherein mounting grooves are respectively formed in the inner sides of two adjacent turbine blade edge plates, two ends of each sealing sheet (1) are respectively inserted into the two adjacent mounting grooves, each sealing sheet (1) comprises a metal functional layer (2) and a ceramic fiber functional layer (3), and the ceramic fiber functional layer (3) is positioned on one side, close to a gas flow G, of each metal functional layer (2).
2. The double-layer composite sealing structure of the turbine blade of the aeroengine, as claimed in claim 1, is characterized in that the middle part of the sealing piece (1) is arched towards the side close to the gas flow G.
3. The double-layer composite sealing structure of the turbine blade of the aeroengine, as set forth in claim 1, is characterized in that the metal functional layer (2) is made of Haynes 214 high-temperature alloy foil.
4. The double-layer composite sealing structure of the turbine blade of the aeroengine, as claimed in claim 1, is characterized in that the ceramic fiber functional layer (3) is made of a Nextel (TM) 440 fiber woven cloth.
5. The double-layer composite sealing structure of the turbine blade of the aeroengine, as claimed in claim 1, is characterized in that a high-temperature-resistant inorganic adhesive layer (4) is arranged between the metal functional layer (2) and the ceramic fiber functional layer (3), and the metal functional layer (2) and the ceramic fiber function are bonded and compounded through the high-temperature-resistant inorganic adhesive layer (4).
6. The double-layer composite sealing structure of the turbine blade of the aeroengine, as set forth in claim 1, wherein the sealing piece (1) is in a thin plate shape, the metal functional layer (2) comprises a middle section (21) and two bending sections (22), the side surface, far away from the gas flow G, of the ceramic fiber functional layer (3) is attached to the middle section (21), the bending sections (22) comprise a first connecting section (221) connected with the middle section (21) and a second connecting section (222) connected with the first connecting section (221), two ends of the ceramic fiber functional layer (3) are attached to the first connecting section (221), and the side surface, close to the gas flow G, of the ceramic fiber functional layer (3) is attached to the second connecting section (222).
7. The double-layer composite sealing structure of the turbine blade of the aeroengine, as set forth in claim 1, is characterized in that the material selected for the metal functional layer (2) is PM2000 ODS alloy foil, and the material selected for the ceramic fiber functional layer (3) is Nextel (TM) 312 fiber needled felt.
8. The double-layer composite sealing structure of the turbine blade of the aeroengine, as claimed in claim 1, is characterized in that the sealing piece (1) is in a continuous corrugated shape, and the metal functional layer (2) and the ceramic fiber functional layer (3) are locally connected at each crest and trough through micro laser spot welding.

Description

Double-layer composite sealing structure of turbine blade of aero-engine Technical Field The application relates to the technical field of sealing of hot end parts of an aeroengine, in particular to a double-layer composite sealing structure of a turbine blade of the aeroengine. Background With the development of aeroengines and gas turbines towards higher thrust-weight ratios and higher thermal efficiency, the temperature before the turbine is continuously increased, which puts extreme demands on the temperature resistance of hot-end components of the turbine, and ceramic matrix composite materials are gradually applied to turbine blades due to their excellent high-temperature performance. However, there is a difference in thermal expansion coefficient between the CMC blade and the metal disk, resulting in dramatic, nonlinear dynamic changes in the clearance between the blade dovetail and disk dovetail slot during operation. The sealing structure of the joint presents unprecedented challenges that the sealing structure must be capable of continuously adapting to a large-range dynamic gap at extremely high temperature, and effectively preventing high-temperature fuel gas from invading into the cavity of the wheel disc. In addition, during the assembly of an aircraft engine turbine blade, a certain amount of clearance must be created between adjacent blade rims. The high temperature gas in the cascade channels may mix through the gaps with the cooling air flow in the engine air system, causing the vanes and platform to be ablated. Therefore, a sealing structure is also necessary to be arranged at the position of the blade edge plate to avoid invasion of high-temperature fuel gas. At present, the sealing schemes mainly comprise two types, namely an elastic sealing piece made of high-temperature alloy, which has certain strength and wear resistance, but insufficient heat insulation performance, is easy to lead to heat conduction to a blade matrix and peripheral components, and is easy to generate oxidation, creep and elastic failure at the current higher and higher temperature, and a ceramic-based sealing piece which is resistant to high temperature, but lacks active elastic restoring force, cannot reliably track dynamic gap change, has poor structural toughness and weak vibration resistance, is easy to fall off and crack under high-frequency vibration, cannot bear blade deformation impact for a long time, and has limited sealing performance. Disclosure of Invention In order to solve the problem that the heat insulation performance and the sealing performance of the turbine blade sealing structure cannot be combined, the application provides a double-layer composite sealing structure for turbine blades of an aeroengine. The application provides a double-layer composite sealing structure of a turbine blade of an aeroengine, which adopts the following technical scheme: The utility model provides an aeroengine turbine blade double-deck compound structure of sealing, includes the piece of sealing, and the mounting groove has been seted up respectively to the relative inboard of two adjacent turbine blade flanges, the both ends of piece of sealing are inserted respectively and are located two adjacent in the mounting groove, the piece of sealing includes metal functional layer and ceramic fiber functional layer, ceramic fiber functional layer is located metal functional layer is close to gas stream G one side. By adopting the technical scheme, the double-layer structure of the metal functional layer and the ceramic fiber functional layer is compounded into an integrated structure, the assembly process is simplified, the production consistency and the maintenance convenience are improved, the double-layer structure also provides failure redundancy, the metal functional layer can still maintain a basic sealing function even if the ceramic fiber functional layer is worn partially, the safety is high, the ceramic fiber functional layer is contacted with high-temperature fuel gas through the functional gradient design of the metal functional layer and the ceramic fiber functional layer, the working temperature of the metal functional layer of a core elastic component of the sealing piece can be reduced while the sealing piece is contacted with the high-temperature fuel gas due to the fact that the fuel gas is scoured and the surface is worn effectively resisted, the service life of the metal functional layer is prolonged, the elasticity of the metal functional layer enables the sealing piece to have excellent flexibility and deformation capability, complex dynamic gap changes caused by different thermal expansion ratios of CMC blades and metal turbine discs can be accurately compensated, sufficient sealing interface sealing is ensured, and therefore the single material performance limit is comprehensively broken through, and the sealing piece can still maintain excellent elastic sealing capability in an ultra-high tempe