Gas Turbine Vane Chordal Seal Parallel Edge Configuration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas turbine vane designs face challenges in maintaining effective sealing between the vane segments and the engine's static structure, leading to potential hot gas flow leakage and reduced efficiency due to variations in manufacturing tolerances and alignment issues.
Innovation Solution
The design incorporates parallel edges on the outer and inner chordal seals, with transition regions and a cusp, to ensure consistent sealing contact with the Blade Outer Air Seal (BOAS) and static structure flange, improving parallelism and manufacturing efficiency by machining these edges simultaneously.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional vane designs are used with standard sealing configurations, then manufacturing is simpler, but sealing effectiveness deteriorates due to manufacturing tolerances and alignment issues causing gas flow leakage
Solution Approach 1:
The patent applies local quality by providing different geometric features at different locations of the seal. The first seal portion has a first edge configuration while the second seal portion has a second edge configuration, allowing each location to be optimized for its specific sealing requirements rather than using a uniform geometry throughout.
Solution Approach 2:
The patent employs curvature principles by configuring the edges of the seal portions to be curved rather than straight. The first edge and second edge are designed with specific curvature profiles that enable them to maintain contact with the corresponding sealing surfaces despite misalignment or tolerance variations, improving sealing effectiveness.
2Manufacturing precision
If multiple machining operations are performed separately on different edges, then manufacturing flexibility is maintained, but manufacturing precision deteriorates due to accumulated tolerances
Solution Approach 1:
The patent merges multiple machining operations into a single simultaneous machining process. By configuring the fixture to machine the first edge and second edge at the same time, the invention eliminates accumulated tolerances from sequential operations and ensures precise parallelism between the edges while maintaining ease of manufacture through fixture-based automation.
Solution Approach 2:
The patent introduces a fixture as an intermediary device that enables simultaneous machining of multiple edges. The fixture acts as a mediator between the machining system and the workpiece, providing precise positioning and alignment that ensures the first and second edges are machined with accurate parallelism in a single operation.
3Reliability
If seal edges are not precisely aligned, then manufacturing is easier, but gas flow leakage increases due to poor sealing contact
Solution Approach 1:
The patent applies preliminary action by pre-configuring the fixture with the precise alignment geometry before machining begins. The fixture is designed with built-in alignment features that automatically establish the correct angular relationship between the first and second edges, eliminating the need for post-machining alignment adjustments and ensuring consistent sealing contact.
Solution Approach 2:
The patent changes the geometric parameters of the seal edges to accommodate alignment variations. By designing the first edge and second edge with specific angular orientations relative to each other and to the axial direction, the invention creates a seal geometry that maintains effective contact even when minor alignment variations occur during manufacturing or assembly.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
An airfoil (90) for a gas turbine engine includes a first airfoil (92). A first chordal seal (102) is located adjacent a first end of the airfoil (92). A second chordal seal (100) is located adjacent a second end of the airfoil (92). The first chordal seal (102) includes a first edge (102a) parallel to a first edge (100a) on the second chordal seal (100).