Turbine Ring Assembly Flange Elastic Compensation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The challenge in gas turbine aeronautical engines is maintaining the position of ceramic matrix composite (CMC) turbine ring sectors amidst differential expansions and contact with metal support structures, which affects engine performance and cooling efficiency.

Innovation Solution

A turbine ring assembly design featuring annular flanges with elastic elements and hooks to secure CMC ring sectors, allowing for differential expansion compensation and improved sealing at high temperatures, along with blocking pins for rotational prevention and a retention flange for easy assembly/disassembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If CMC ring sectors are used to reduce cooling ventilation, then cooling requirements are reduced, but maintaining position against differential expansion becomes problematic

Engineering Contradiction:
Improvecooling ventilationVSAvoidposition maintenance
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The patent introduces elastic elements that change their mechanical parameters (elastic deformation) in response to temperature changes, allowing the connection between CMC ring sectors and metal support structure to adapt to differential thermal expansion while maintaining secure positioning

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The elastic elements act as intermediary components between the CMC ring sectors and the metal support structure, absorbing the differential expansion through their elastic deformation and preventing direct stress concentration that would compromise positioning reliability

Inventive Principle:
Principle #24Intermediary (Mediator)

2Strength

If metal support structure is used to hold ring sectors, then structural strength is provided, but differential expansion causes positioning problems

Engineering Contradiction:
Improvesupport structure strengthVSAvoidring sector positioning
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The patent transforms the static rigid connection into a dynamic system where elastic elements can deform to accommodate thermal expansion differences, allowing the support structure to maintain both strength and positioning precision under varying temperature conditions

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent explicitly accounts for thermal expansion by designing the elastic elements to compensate for the differential expansion between metal and CMC materials, ensuring that positioning precision is maintained despite the inherent expansion differences

Inventive Principle:
Principle #37Thermal expansion

3Reliability

If compulsory travel constraints are applied to maintain position, then positioning is improved, but device complexity increases

Engineering Contradiction:
Improvering sector positioningVSAvoidconstraint mechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The elastic elements provide self-adjusting positioning through their inherent elastic properties, automatically compensating for thermal expansion without requiring complex external constraint mechanisms, thus maintaining positioning reliability while minimizing device complexity

Inventive Principle:
Principle #25Self-service

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 design effectively maintains ring sector position and enhances sealing, reducing the need for cooling ventilation and accommodating thermal expansion, thereby improving engine performance and efficiency.

Implementation Method 1

at least one elastic element being interposed between the annular projection of the first flange and the annular groove of the first tab and between the annular projection of the second flange and the annular groove of the second tab

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

maintaining the ring sectors in position remains a problem, particularly with regard to the differential expansions which can occur between the metal support structure and the CMC ring sectors

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP3298247B1Turbine ring assembly supported by flanges
Publication Date: 2023.10.25 SAFRAN AIRCRAFT ENGINES SAS
  • EP3298247B1 patent drawingFigure 1
  • EP3298247B1 patent drawingFigure 2~3
  • EP3298247B1 patent drawingFigure 4~5

AI summary

The invention relates to a turbine ring assembly which comprises a plurality of ring sectors (10) made of a composite material with a ceramic matrix forming a turbine ring (1) and a ring-supporting structure (3) including two flanges (32, 36). The ring sectors comprise two tabs (14, 16) which extend between the two annular flanges of the ring-supporting structure and each includes an annular groove (140, 160) into which an annular projection (34, 38) on each of the flanges of the ring-supporting structure is inserted. A resilient element (60; 70) is intercalated between the upper wall of the projection and the upper wall of the corresponding groove or between the lower wall of the projection and the lower wall of the corresponding groove.