Wishbone-Shaped Fiber Layer Structure for CMC Vane Flange Attachment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Implementing ceramic matrix composite (CMC) materials in gas turbine engine airfoils poses challenges due to lower material stress limits compared to metallic superalloys, requiring new attachment schemes that avoid stress concentration and complex geometries difficult to manufacture in composites.
Innovation Solution
The use of fiber-reinforced composite airfoil sections with wishbone-shaped fiber layer structures and flanges that integrate into the fairing platform, allowing for simplified and robust attachment while managing thermal and structural loads, and featuring cavity fiber plies that circumscribe internal cavities and extend into the fairing platform to form flanges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If CMC materials are used in airfoils to achieve high temperature resistance, then temperature capability is improved, but material stress limit decreases making attachment difficult
Solution Approach 1:
The patent employs fiber-reinforced composite materials with a wishbone-shaped fiber layer structure to create an attachment scheme that accommodates the lower stress limits of CMC materials while maintaining structural integrity. The composite structure distributes stresses through multiple fiber layers and geometric configurations, enabling CMC airfoils to be attached without exceeding material stress limits.
2Reliability
If complex attachment geometries are used to improve attachment strength, then reliability is improved, but manufacturing difficulty increases
Solution Approach 1:
The attachment structure is segmented into distinct functional zones including the wishbone-shaped fiber layer structure, flange regions, and fairing platform integration zones. This segmentation allows each component to be manufactured and assembled separately, reducing overall manufacturing complexity while maintaining attachment reliability through optimized stress distribution in each segment.
Solution Approach 2:
The fiber layer structure implements local quality variations with different fiber orientations, densities, and material properties in different regions of the attachment. The wishbone shape provides enhanced fiber density and orientation in high-stress areas while maintaining simpler structures in low-stress regions, optimizing both reliability and manufacturability.
3Strength
If flange structures are added to improve attachment capability, then attachment strength is improved, but device complexity increases
Solution Approach 1:
The flange structures are merged with the fairing platform to create an integrated attachment system. The wishbone-shaped fiber layer structure transitions seamlessly into the flange regions, which are then integrated with the fairing platform, eliminating separate components and reducing overall device complexity while maintaining enhanced attachment capability.
Data Source
Figure 1~2
Figure 3~4
Figure 5A~5B
AI summary
A vane arc segment (60) includes an airfoil fairing (62) that has a fairing platform and an airfoil section (64) that extends there from. The fairing platform defines a gaspath side (66a/68a) and a non-gaspath side (66b/68b)and includes a flange (80) that projects from the non-gaspath side (66b/68b). The airfoil fairing (62) is formed of a fiber-reinforced composite (65) that includes a wishbone-shaped fiber layer structure (82) that has first and second arms (82a/82b) that converge and merge into a single leg (82c). The first and second arms (82a/82b) are formed of fiber plies (84) comprised of a network of fiber tows (83). The single leg (82c) comprises fiber tows (83) from each of the fiber plies (84) of the first and second arms (82a/82b). The fiber tows (83) of the first arm (82a) are interwoven in the single leg (82c) with the fiber tows (83) of the second arm (82b). The first arm (82a), the second arm (82b), or the single leg (82c) forms at least a portion of the flange (80).