Composite Blade Leading Edge With Thin Metal Layer Erosion Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Manufacturing a leading-edge cover for composite blades in industrial gas turbines to counter water droplet erosion is challenging due to the difficulty in processing thin, curved metallic materials like titanium alloy, and existing solutions result in excessive collision resistance and reduced lightness.
Innovation Solution
A composite blade with a metal layer of 5-100 micrometers thickness bonded to the leading edge via an adhesive layer, incorporating a super-hard metal layer and a soft metal layer to provide corrosion resistance and fatigue strength while maintaining lightness, and an electric insulating layer to prevent electrical erosion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a metallic material such as titanium alloy is used for the leading-edge cover member, then corrosion resistance and fatigue strength are improved, but ease of manufacture deteriorates due to difficulty in processing thin, curved shapes
Solution Approach 1:
The patent applies composite materials by bonding a metal layer (5-100 micrometers thick) to a composite blade body. This allows the leading edge to have the corrosion resistance and fatigue strength of metallic materials while the overall structure maintains the manufacturing advantages of composite materials. The thin metal layer can be applied to complex curved surfaces without the processing difficulties associated with bulk titanium alloy manufacturing.
Solution Approach 2:
The patent changes the parameter of metal layer thickness to 5-100 micrometers, which is sufficiently thin to be manufactured on complex curved surfaces yet thick enough to provide the required corrosion resistance and fatigue strength. This parameter optimization resolves the contradiction between protective performance and manufacturability.
2Strength
If a massive metallic leading-edge cover member is used, then collision resistance is improved, but weight increases which reduces the lightness advantage of composite blade bodies
Solution Approach 1:
The patent uses a thin metal layer (5-100 micrometers) instead of a massive metallic cover. This thin film provides sufficient protection against water droplet erosion while maintaining the lightness advantage of composite blade bodies. The thin layer is sufficient for the lower energy water droplet impacts in industrial gas turbines compared to bird strikes in aircraft engines.
Solution Approach 2:
The patent applies metal layering locally only to the leading edge section where water droplet erosion occurs, rather than making the entire blade massive. This localized application provides collision resistance exactly where needed while preserving the overall lightness of the composite blade structure.
3Weight of moving object
If a metal layer with thickness of 5-100 micrometers is provided on the leading edge section, then water droplet erosion protection is achieved while maintaining lightness, but manufacturing precision is required to ensure proper bonding and thickness control
Solution Approach 1:
The patent employs preliminary actions in the manufacturing process, including surface treatment of the composite blade body before bonding, and controlled application of the metal layer at 5-100 micrometers thickness. These preliminary preparations ensure proper adhesion and uniform thickness, achieving the required manufacturing precision for such a thin critical layer.
Solution Approach 2:
The patent uses an adhesive layer as an intermediary between the composite blade body and the metal layer. This adhesive mediator ensures proper bonding of the thin metal layer (5-100 micrometers) to the composite substrate, achieving the necessary manufacturing precision and structural integrity that would be difficult to obtain through direct bonding alone.
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 solution effectively addresses water droplet erosion in industrial gas turbines by providing a lightweight, corrosion-resistant, and fatigue-strength-enhanced composite blade with reduced risk of electrical erosion and improved aerodynamic efficiency.
Implementation Method 1
an adhesive layer provided between the composite blade body and the metal layer to bond the metal layer to the composite blade body
Implementation Method 2
the presence of the adhesive layer having an electric insulating property can suppress the electrical erosion of the metal layer
Data Source
AI summary
A composite blade includes a composite blade body including reinforced fibers and resin; a metal layer provided on an outer side of a leading edge section including a leading edge that is a part of the composite blade body on an upstream side of an air stream, the metal layer having a thickness of equal to or larger than 5 micrometers and equal to or smaller than 100 micrometers; an adhesive layer provided between the composite blade body and the metal layer to bond the metal layer to the composite blade body; and an electric insulating layer provided in contact with a surface of the leading edge section of the composite blade body, the surface being on the side on which the metal layer is provided, the electric insulating layer having an electric insulating property.