CMC Blade Root Reinforcement for Centrifugal Load Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing blades in gas turbine engines, particularly long blades in later stages, face severe stress and risk of root collapse due to high centrifugal forces and high temperatures, which conventional ceramic matrix composite materials struggle to withstand effectively.
Innovation Solution
A blade design featuring diverging walls made of ceramic matrix composite material with a reinforcement element, such as metal, between the walls, and potentially additional intermediate layers of different materials, along with a sacrificial layer and bonding layer to enhance structural integrity and reduce stress concentration, is proposed. The reinforcement element is strategically placed between the diverging walls to counteract centrifugal forces and prevent root collapse.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If blades are made of ceramic matrix composite material with hollow shell structure, then weight is reduced and temperature resistance is improved, but structural strength and resistance to centrifugal forces deteriorate
Solution Approach 1:
The patent employs a composite structure combining ceramic matrix composite material (for heat resistance) with metal reinforcement elements (for mechanical strength). The metal element is embedded within the ceramic matrix structure, creating a hybrid composite that leverages the thermal properties of ceramics and the mechanical properties of metals to simultaneously achieve temperature resistance and structural strength.
2Weight of moving object
If hollow shell structure is used in blade root, then weight is reduced, but resistance to centrifugal forces and risk of collapse deteriorate
Solution Approach 1:
The patent applies local reinforcement by embedding metal reinforcement elements specifically in the blade root region where centrifugal forces are most severe. The hollow shell structure is maintained in less critical areas to preserve weight benefits, while localized metal reinforcement provides the necessary strength and collapse resistance in the high-stress root region.
3Strength
If reinforcement element is added between diverging walls, then structural integrity is improved, but device complexity increases
Solution Approach 1:
The patent integrates the metal reinforcement element within the existing ceramic matrix structure, merging two different materials into a unified composite component. The reinforcement element is strategically positioned between the diverging walls of the blade root, combining the structural support function with the overall blade geometry to enhance integrity without requiring separate attachment mechanisms or complex assembly procedures.
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 design significantly reduces the risk of root collapse during operation by distributing loads effectively and managing centrifugal forces, ensuring the structural integrity and longevity of the blade under severe conditions.
Implementation Method 1
The blades have to withstand very severe conditions, due for example to the high centrifugal forces and the high temperature of the gas they are immersed in
Implementation Method 2
blades made of ceramic matrix composite material (CMC) have been proposed. CMC is a composite material having carbon or ceramic fibres and a ceramic matrix
Data Source
Figure 1~2
Figure 3~4
Figure 5~7
AI summary
The blade (1) comprises an airfoil (2) and a root (3) having diverging walls (7). The diverging walls (7) are made of a ceramic matrix composite material. A reinforcement element (8) is provided between the diverging walls (7).