Elastomeric Seal for Gas Turbine Leakage Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Gas turbine engines face inefficiencies due to fluid leakage between the bypass passage and the core engine, which affects thermal, transfer, assembly, and propulsive efficiencies.

Innovation Solution

A seal structure, including a flexible, hollow, and elastomeric vane with a rounded bulb or flap design, is used to control fluid leakage between the bypass passage and the core engine, featuring an attachment section with spaced-apart legs and a wear member to secure the seal in place, reducing gas flow through gaps.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a seal structure is added to control fluid leakage, then thermal efficiency and propulsive efficiency are improved, but device complexity increases

Engineering Contradiction:

Improvefluid leakageVSAvoidseal structure

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The patent employs a flexible seal structure comprising an elastomeric material that can deform to accommodate thermal growth and dimensional tolerances. The seal includes a radially inwardly extending flap that flexibly contacts the vane structure, creating an effective barrier against fluid leakage without requiring complex rigid sealing mechanisms. This flexible approach resolves the contradiction by providing effective sealing while maintaining structural simplicity.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The seal structure utilizes changes in physical parameters including temperature-induced thermal expansion and material elasticity. The elastomeric seal material is selected to maintain sealing effectiveness across a range of temperatures and pressures, adapting its properties to compensate for thermal growth in the engine components. This parameter-based adaptation allows the seal to function effectively without adding complex control mechanisms.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a rigid seal is used to prevent fluid leakage, then sealing effectiveness is improved, but adaptability to thermal growth and dimensional tolerances deteriorates

Engineering Contradiction:

Improvesealing effectivenessVSAvoidthermal growth accommodation

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The seal structure transitions from a static rigid design to a dynamic flexible system. The elastomeric material and flap configuration allow the seal to move and deform in response to thermal expansion and dimensional variations in the engine components. This dynamic adaptability ensures continuous sealing effectiveness despite changes in operating conditions, resolving the contradiction between reliable sealing and adaptability to thermal growth.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The flexible elastomeric seal acts as a compliant barrier that can deform to accommodate dimensional tolerances and thermal growth. Unlike rigid seals that would require precise clearance control, the flexible seal naturally adapts to component variations while maintaining sealing effectiveness. This approach simultaneously achieves reliable sealing and adaptability to thermal and dimensional changes.

Inventive Principle:

Principle #30Flexible shells and thin films

3Loss of energy

If multiple seals are installed to control leakage at different locations, then fluid leakage control is improved, but manufacturing complexity and assembly difficulty increase

Engineering Contradiction:

Improvefluid leakage controlVSAvoidassembly complexity

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The patent combines multiple sealing functions into a single integrated seal structure. The elastomeric seal with its radially inwardly extending flap configuration simultaneously addresses leakage at the interface between the bypass passage and core engine, as well as accommodating thermal growth and dimensional tolerances. This consolidated design reduces the number of separate sealing components required, simplifying both manufacturing and assembly processes while maintaining effective leakage control.

Inventive Principle:

Principle #5Merging (Combining)

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 seal effectively minimizes fluid leakage, enhancing the aerodynamic performance and overall efficiency of the engine by maintaining optimal operating conditions and reducing the impact of thermal growth and dimensional tolerances.

Implementation Method 1

The seal is flexible and includes a rounded, hollow bulb

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

the seal is hollow... the seal includes a rounded, hollow bulb

Methodology Applied

Scientific EffectCompression: Compression

Data Source

PatentUS9909503B2Gas turbine engine including vane structure and seal to control fluid leakage

Publication Date: 2018.03.06 RTX CORP

AI summary

A gas turbine engine includes a core engine, a fan coupled to be driven by the core engine, a first case structure around the core engine and a second case structure around the fan. The first case structure and the second case structure define a bypass passage there between. A vane structure includes an airfoil extending radially between the first case structure and the second case structure. A seal is configured to control leakage between the bypass passage and a core engine.