C-Shaped Protective Liners for Turbomachine Rotor Disk Sealing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing turbomachine fan rotor disk designs suffer from air leaks due to clearance between platforms and blade airfoil sections, leading to reduced efficiency, and previous solutions to restore the seal have made turbomachines heavier by incorporating additional components.

Innovation Solution

The use of C-shaped protective liners with a helicoidal profile between the disk flanks and blade roots, which also radially retain inter-blade platforms, minimizing clearance and allowing perfect curvature alignment between platform edges and blade airfoil sections, thereby eliminating the need for axial insertion and reducing wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If additional components are incorporated to restore the seal between platform and blade, then air leaks are reduced, but the turbomachine becomes heavier

Engineering Contradiction:

Improveair leaksVSAvoidturbomachine weight

Core Design Contradiction:

Object-affected harmful factorsVSWeight of moving object

Solution Approach 1:

The protective liner is given multiple functions: it protects the blade root from friction wear and simultaneously retains the platform on the rib through its C-shaped cross section. This eliminates the need for separate sealing components, reducing weight while effectively preventing air leaks between the platform and blade airfoil sections.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The invention merges the protective function and the retention function into a single integrated component (the protective liner). By combining these functions, the design eliminates additional sealing components that would increase weight, while the C-shaped cross section effectively seals the clearance between platform and blade.

Inventive Principle:

Principle #5Merging (Combining)

2Ease of operation

If clearance is increased to allow platform insertion, then ease of assembly is improved, but air leaks toward the disk increase

Engineering Contradiction:

Improveplatform assemblyVSAvoidair leaks

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

Instead of inserting the platform axially through large clearance, the invention inverts the approach by using the C-shaped protective liner to radially retain the platform. This allows the platform to be positioned with minimal clearance for effective sealing, while the liner's geometry facilitates assembly through radial retention rather than axial insertion.

Inventive Principle:

Principle #13The other way round (Inversion)

3Object-affected harmful factors

If platform edges are curved to match blade airfoil, then sealing is improved, but manufacturing complexity increases

Engineering Contradiction:

Improveair leaksVSAvoidplatform manufacturing

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The C-shaped protective liner acts as an intermediary that enables the platform edges to perfectly match the blade airfoil curvature. The liner's geometry facilitates this precise alignment, allowing curved platform edges for effective sealing without significantly increasing manufacturing complexity, as the curvature is dictated by the blade airfoil profile itself.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS8277188B2Turbomachine rotor disk

Publication Date: 2012.10.02 SAFRAN AIRCRAFT ENGINES SAS

AI summary

A turbomachine rotor disk including inter-blade platforms fixed to ribs delimited by cavities in which blade roots are retained, and protective liners mounted between the flanks of the cavities of the disk and the blade roots is disclosed. The protective liners have a C-shaped cross section so that they can be fitted translationally and retained radially on the ribs of the disk and constitute a locking device which locks the platforms on the ribs of the disk.