Gas Turbine Stator Segment Seal Assembly

Solution Overview

Problem

Gas turbine engines experience efficiency reduction due to airflow leaks through inter-segment gaps, and existing sealing solutions often require substantial redesign or rework, increasing costs and weight.

Innovation Solution

A seal assembly comprising a hollow member made of a first material with a fill of a second material, featuring a pedestal that engages multiple surfaces and extends between segments to bridge gaps, providing a compressible seal that minimizes leakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a thin sealing strip is used in machine grooves to seal inter-segment gaps, then sealing effectiveness is improved, but substantial redesign or rework is required which increases cost and weight

Engineering Contradiction:

Improvesealing effectivenessVSAvoidredesign and rework requirements

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The seal assembly is nested within an existing groove or recess in the vane segment structure. The hollow member with fill material is inserted into a pre-existing groove, allowing the sealing function to be added without requiring substantial redesign of the base structure. This nesting approach enables the seal to be housed within existing geometric features of the gas turbine engine components.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The seal assembly uses a composite structure combining a hollow member made of one material with a fill material of different properties. This composite construction provides both structural support and sealing functionality, allowing the seal to be effective while minimizing the need for extensive modifications to existing parts. The combination of materials enables the seal to adapt to existing geometries while maintaining sealing effectiveness.

Inventive Principle:

Principle #40Composite materials

2Reliability

If a thin sealing strip is used in machine grooves to seal inter-segment gaps, then sealing effectiveness is improved, but weight increases due to substantial redesign

Engineering Contradiction:

Improvesealing effectivenessVSAvoidcomponent weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The seal assembly is nested within an existing groove or recess in the vane segment structure. The hollow member with fill material is inserted into a pre-existing groove, allowing the sealing function to be added without requiring substantial redesign of the base structure. This nesting approach enables the seal to be housed within existing geometric features of the gas turbine engine components.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The seal assembly employs a hollow member that can be made from thin-walled material, providing sealing functionality with minimal material usage. The hollow structure allows the seal to be effective while keeping weight low, as the thin walls provide sufficient sealing capability without adding substantial mass to the moving components of the gas turbine engine.

Inventive Principle:

Principle #30Flexible shells and thin films

3Reliability

If existing parts are modified to incorporate sealing strips, then sealing is achieved, but cost increases due to rework

Engineering Contradiction:

Improvesealing performanceVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The seal assembly is nested within an existing groove or recess in the vane segment structure. The hollow member with fill material is inserted into a pre-existing groove, allowing the sealing function to be added without requiring substantial redesign of the base structure. This nesting approach enables the seal to be housed within existing geometric features of the gas turbine engine components.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The seal assembly uses a simple hollow member structure that can be manufactured cost-effectively. The design allows for a straightforward manufacturing process where the hollow member is produced and then filled with sealing material, creating an affordable sealing solution that does not require expensive custom fabrication or extensive rework of existing parts.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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 assembly effectively reduces airflow leakage between segments of the gas turbine engine, enhancing efficiency with minimal impact on cost and weight by integrating seamlessly into existing components.

Implementation Method 1

providing a compressible seal that minimizes leakage

Methodology Applied

Scientific EffectCompression: Compression

Data Source

PatentEP3477061B1Stator segment circumferential gap seal

Publication Date: 2021.10.27 RTX CORP

Figure 1
Figure 2~3
Figure 4

AI summary

A vane assembly (60) for a gas turbine includes a first shroud segment (84), a second shroud segment (86), a first inner air seal (110), and a seal assembly (82). The first shroud segment (84) has a first end face (90). The second shroud segment (86) is disposed adjacent to the first shroud segment (84) and has a second end face (92) that faces towards and is spaced apart from the first end face (90) by a gap (94). The first inner air seal (110) extends into the first shroud segment (84) and defines a first trench (124). The seal assembly (82) at least partially received within the first trench (124).