Gas Turbine Vane Assembly Sealing with Resilient Grommet Insert
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas turbine engine vane assemblies face challenges in achieving a reliable seal between the vane root and casing slot to reduce pressure loss, while also seeking to minimize weight and improve manufacturing ease, particularly at the fan outer case.
Innovation Solution
A vane assembly comprising a resilient grommet around the vane tip and a closed-loop insert with hooks and a protruding lip, designed to securely engage with the slot, ensuring a sealed and trapped position, which includes a method of inserting the insert into the slot, flexing its hooks, and sliding the vane radially inward until the grommet is snugly engaged with the insert.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a grommet is used around the vane root to provide a seal, then pressure loss is reduced, but device complexity increases
Solution Approach 1:
The grommet and insert are combined into a single integrated component. The grommet is formed as an integral part of the insert, eliminating the need for separate sealing and mounting components. This merging reduces device complexity while maintaining the sealing function that prevents pressure loss.
Solution Approach 2:
The integrated grommet-insert component performs multiple functions simultaneously: it provides sealing against the slot surfaces, serves as a mounting structure with hooks for installation, and acts as a retaining feature. This multi-functionality reduces the number of separate components needed, thereby reducing device complexity while maintaining effective sealing.
2Reliability
If vanes have enlarged step or flange portions for receipt within the grommet, then sealing is improved, but weight increases
Solution Approach 1:
The sealing function is separated from the vane structure itself and placed in the grommet component. Instead of modifying the vane with heavy flange portions, the sealing is achieved through the grommet's contact surfaces against the slot. This segmentation allows the vane to remain lightweight while the separate grommet provides the necessary sealing.
Solution Approach 2:
The grommet provides localized sealing quality at the interface between the vane and slot without requiring the entire vane structure to be heavier. The resilient material of the grommet creates effective sealing contact at specific locations, maintaining reliability while avoiding unnecessary weight increase in the moving vane components.
3Ease of manufacture
If hooks are made resilient and inwardly flexible for easy installation, then ease of manufacture is improved, but structural integrity may be compromised
Solution Approach 1:
The hooks are designed with resilient properties that allow them to dynamically adapt during installation - flexing inward to pass through the slot and then springing outward to engage and lock. This dynamic behavior enables easy installation while maintaining structural integrity in the final assembled state, as the hooks transition from a flexible installation state to a rigid retained state.
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 effectively reduces pressure loss by creating a sealed engagement between the vane and the slot, enhances the structural integrity to withstand operational loads and foreign object damage, and simplifies the assembly process by using a combination of materials and design features that are more resilient and adaptable.
Implementation Method 1
having hooks being resilient and inwardly flexible to engage the insert into one end of the slot, the hooks biased outwardly for engaging with a corresponding feature of the case
Implementation Method 2
an outwardly protruding lip shaped to abuttingly and sealingly engage a corresponding surface of the case around the slot
Implementation Method 3
the grommet being of a material more resilient than a material of the airfoil body, the grommet having an outer surface surrounding the tip
Data Source
AI summary
The gas turbine engine vane assembly has a vane having an elongated airfoil body extending to a tip and a grommet disposed around the tip. An insert having a closed loop shape with an inner surface matingly shaped to receive the outer surface of the grommet, and an outer surface matingly shaped to be snugly received in the slot. A method of mounting such a vane assembly is also disclosed.