Gas Turbine Airfoil Platform with Sloping Shoe Sections
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current gas turbine engine designs face challenges in efficiently managing airflow and stress distribution across airfoil platforms, particularly in high-bypass ratio engines, where traditional dovetail geometries can lead to stress concentrations and complex mounting requirements.
Innovation Solution
The introduction of a platform with sloping platform portions and shoe sections that establish a gas path surface, integrated with retention members and seal members, to secure airfoils within slots on the hub, reducing stress concentrations and simplifying the mounting process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If traditional dovetail geometries are used for airfoil mounting, then the airfoil can be securely mounted in the hub, but stress concentrations occur and mounting requirements become complex
Solution Approach 1:
The airfoil assembly is segmented into distinct functional components: the airfoil section, the platform with sloping platform portions, the shoe sections, and the retention members. This segmentation allows each component to be optimized independently - the platform portions can be designed to distribute stress while the retention members provide secure mounting, thereby reducing overall complexity while maintaining strength
Solution Approach 2:
The platform with sloping platform portions acts as an intermediary element between the hub and the airfoil. This intermediate structure distributes loads across multiple surfaces and reduces stress concentrations by spreading the mounting forces over a larger area, eliminating the need for complex dovetail geometries while maintaining secure mounting
2Device complexity
If traditional airfoil configurations are used, then the structure is simple, but aerodynamic performance and stress distribution are inadequate
Solution Approach 1:
The airfoil assembly incorporates local quality variations through the sloping platform portions and shoe sections that are specifically designed to address stress concentration zones. These localized structural modifications improve stress distribution and aerodynamic performance without requiring complete redesign of the entire airfoil structure, maintaining overall simplicity while enhancing reliability
3Reliability
If additional mounting features are added to reduce stress concentrations, then stress distribution improves, but the assembly process becomes more complex
Solution Approach 1:
The platform, shoe sections, and retention members are merged into an integrated assembly that performs multiple functions simultaneously: the sloping platform portions distribute stress while the retention members secure the airfoil, and the shoe sections provide additional support. This merging eliminates the need for separate mounting features while improving stress distribution and simplifying the assembly process
Data Source
Figure 1
Figure 2~2A
Figure 3
AI summary
An airfoil assembly for a gas turbine engine (20) according to an example of the present disclosure includes, among other things, an airfoil (164) that has an airfoil section (168) extending from a root section (170). The airfoil section (168) extends between a leading edge (168L) and a trailing edge (168T) in a chordwise direction (X) and extends between a tip portion and the root section (170) in a radial direction (R), and the airfoil section (168) defining a pressure side (168P) and a suction side (168S) separated in a circumferential direction (T). A platform (174) includes a first and second platform portions (175-1, 175-2) attached to the root section (170). Each of the first and second platform portions (175-1, 175-2) includes a shoe section (178) and a platform section (174) extending in the circumferential direction (T) from the shoe section (178) to establish a gas path surface (GS), and the shoe sections (178) of the first and second platforms (175-1, 175-2) are circumferentially arranged on opposed sides of the root section (170) to capture the root section (170) in a root cavity (184) established between the shoe sections (178). A method of assembly is also disclosed.