Segmented Heat Shield Mechanical Linkage for Gas Turbine

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional heat shield mounting methods in gas turbine engine structural components are inadequate, as welded joints are difficult to remove and spring-loaded designs are not robust enough for industrial applications, necessitating a more effective coupling arrangement to prevent vibration and thermal distortion.

Innovation Solution

A system utilizing a combination of slip joints and fixed joints to securely attach heat shields to the fairing, allowing for removable and repetitive attachment while accommodating thermal expansion, using anchor mechanisms like shelves and slots to prevent excessive movement and stress on the heat shield.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If heat shields are welded to the TEC structural frame, then the heat shield is securely attached and vibration is prevented, but the heat shield cannot be easily removed or repositioned

Engineering Contradiction:
Improveheat shield attachment securityVSAvoidheat shield removability
Core Design Contradiction:
ReliabilityVSEase of repair

Solution Approach 1:

The heat shield attachment system is divided into separate components: a heat shield with attachment features and a structural frame with corresponding receptacles. This segmentation allows the heat shield to be detachably connected rather than permanently welded, enabling easy removal and repositioning while maintaining secure attachment during operation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The attachment system transitions from a static welded connection to a dynamic detachable connection. The heat shield can be securely attached during operation to prevent vibration, yet can be easily detached for removal or repositioning. This dynamic capability resolves the contradiction between secure attachment and ease of repair.

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If heat shields are spring-loaded or biased against the frame, then the heat shield is held in position, but the design is not robust enough for industrial gas turbine applications

Engineering Contradiction:
Improveheat shield positioningVSAvoiddesign robustness
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention introduces intermediary attachment features (attachment members on the heat shield and corresponding receptacles on the frame) that mediate between the heat shield and frame. This intermediary mechanism provides robust, positive mechanical engagement suitable for industrial gas turbine applications, replacing the insufficient spring-loaded design while maintaining ease of positioning.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Object-generated harmful factors

If the heat shield is rigidly fixed to prevent vibration, then vibration wear is reduced, but thermal expansion and distortion are constrained

Engineering Contradiction:
Improvevibration wearVSAvoidthermal expansion freedom
Core Design Contradiction:
Object-generated harmful factorsVSStability of the object's composition

Solution Approach 1:

The attachment system is designed to accommodate parameter changes due to thermal effects. The detachable connection allows for controlled movement and expansion of the heat shield under thermal loading, preventing constraint-induced distortion while maintaining sufficient attachment to reduce excessive vibration wear during normal operation.

Inventive Principle:
Principle #35Parameter changes

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

This solution provides a robust and removable heat shield mounting system that prevents vibration and thermal distortion, reducing wear and stress on the heat shield and surrounding components, while allowing for easy assembly and disassembly in tight spaces.

Implementation Method 1

The heat shields provide thermal protection to the structural frame by inhibiting conductive heat transfer from the fairing to the structural frame

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

allowing for removable and repetitive attachment while accommodating thermal expansion

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP2938863B1Mechanical linkage for segmented heat shield
Publication Date: 2019.09.25 UNITED TECH CORP
  • EP2938863B1 patent drawingFigure 1
  • EP2938863B1 patent drawingFigure 2A
  • EP2938863B1 patent drawingFigure 2B

AI summary

A turbine exhaust case comprises a frame, a fairing, a heat shield and a mechanical linkage. The frame comprises an outer ring, an inner ring, and a plurality of struts joining the outer ring and the inner ring. The fairing comprising a ring-strut-ring structure disposed within the frame. The heat shield is disposed between the frame and the fairing. The mechanical linkage couples the heat shield to the fairing. In one embodiment, the heat shield comprises a multi-piece heat shield that inhibits heat transfer between the frame and the fairing. In various embodiments, the mechanical linkage comprises a slip joint or a fixed joint for coupling the heat shield to the fairing.