Split-Hoop J-Shaped Seal for Gas Turbine Deflection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing seals in gas turbine engines fail to effectively manage secondary flow and temperature variations, leading to premature failure and inefficiencies due to significant relative deflections and elevated temperatures, which limits their use and performance.
Innovation Solution
A split-hoop seal design with radially-extending rails and axially-extending legs, featuring slots and holes that allow controlled gas flow, providing radial preload and improved durability through high-temperature materials and configurations that adapt to component movements, ensuring effective sealing and cooling while resisting deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional metal w-seal or non-metallic rope seal is used, then sealing function is provided, but the seal fails prematurely under significant relative deflections and elevated temperatures
Solution Approach 1:
The seal design changes its geometric parameters dynamically through the slots and holes that allow controlled deformation. The split-hoop configuration with radially-extending rails and axially-extending legs enables the seal to adapt its shape in response to thermal expansion and mechanical deflections, maintaining sealing contact under varying operating conditions without premature failure
Solution Approach 2:
The seal is divided into segmented components including radially-extending rails, axially-extending legs, and controlled openings (slots and holes). This segmentation allows each component to move and deform independently, accommodating relative deflections between turbine components while maintaining overall sealing integrity and reliability
2Temperature
If slots and holes are added to allow gas flow, then temperature management is improved, but seal structure complexity increases
Solution Approach 1:
The slots and holes in the seal structure serve multiple functions simultaneously: they enable temperature management through controlled gas flow, allow the seal to adapt to thermal expansion, and maintain sealing effectiveness. This multi-functionality reduces the need for separate cooling systems while managing temperature effectively
Solution Approach 2:
The seal incorporates slots and holes at specific locations (in the radially-extending rails and axially-extending legs) where gas flow is most needed for temperature management. This localized approach to complexity ensures temperature control is provided precisely where thermal conditions require it, without unnecessarily complicating the entire seal structure
3Reliability
If radial preload is achieved by making seal inner diameter smaller than cavity inner diameter, then sealing contact is improved, but seal stress increases
Solution Approach 1:
The seal design transitions from a static preloaded configuration to a dynamic system where the split-hoop structure with slots and holes allows the seal to adjust its contact pressure in response to operating conditions. The radial preload is maintained through the biased configuration, but the seal can dynamically accommodate stress variations without losing sealing contact
Solution Approach 2:
The segmented structure with radially-extending rails and axially-extending legs allows stress distribution across multiple components. The segmentation enables the seal to maintain sealing contact through distributed contact points while reducing stress concentration that would occur in a solid, non-segmented seal under the same preload conditions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enhances sealing efficiency, durability, and temperature management, reducing leakage and wear, and enabling the use of lower-strength, higher-temperature materials, while maintaining contact with components during relative movements, thus improving engine performance and component life.
Implementation Method 1
a plurality of slots formed into at least one of the rail and the leg; wherein the plurality of slots allows a flow of gas from a first side of the seal to a second side of the seal
Implementation Method 2
a first seal free-state inner diameter that is smaller than a seal cavity inner diameter, such that a radial preload is achieved between the first seal and at least one of the first and second components
Data Source
AI summary
The present disclosure relates generally to a sliding seal between two components. The sliding seal includes a substantially radially extending rail and a substantially axially extending leg, such that the seal has a substantially J-shaped cross-section.