Wind Turbine Rotor Blade Trailing-Edge Wedge-Core Bonding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional wind turbine rotor blades face challenges with structural stiffness, buckling resistance, and strength due to the use of heavy and expensive bond paste at joints, which can generate excess heat and safety hazards, and are difficult to reinforce without increasing weight or cost.

Innovation Solution

A method involving a wedge-shaped core material, such as high-density foam, is infused with dry skin layers to form a first shell member, providing a mounting surface for adhesive connection with a second shell member, eliminating the need for silicone profiles and reducing material weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If heavy bond paste is used to provide structure at blade joints, then structural strength and buckling resistance are improved, but weight increases and safety hazards arise from excess heat generation

Engineering Contradiction:
Improvestructural strengthVSAvoidblade weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The blade is divided into two separate shell members (first shell member and second shell member) that are joined at the trailing edge. The wedge-shaped core material is segmented into a mounting surface portion and a trailing edge portion, allowing independent optimization of each component's function and weight characteristics.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention uses a composite structure combining the wedge-shaped core material (with mounting surface and trailing edge portions) with the two shell members. This composite design replaces heavy bond paste with a lightweight composite assembly that achieves superior structural strength through geometric configuration and material composition rather than mass.

Inventive Principle:
Principle #40Composite materials

2Strength

If heavy bond paste is used at joints, then structural integrity is improved, but manufacturing cost increases

Engineering Contradiction:
Improvejoint integrityVSAvoidmanufacturing cost
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The wedge-shaped core material is pre-formed with a mounting surface portion and a trailing edge portion before assembly. This preliminary fabrication allows precise geometric control and eliminates the need for complex on-site bonding operations, reducing both material waste and manufacturing complexity.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention extracts and eliminates the need for heavy bond paste from the joint construction. Instead of applying substantial adhesive material, the design uses the geometric configuration of the wedge-shaped core material and shell members to provide structural integrity, thereby removing the costly and heavy bonding material entirely.

Inventive Principle:
Principle #2Taking out (Extraction)

3Productivity

If thick adhesive sections with fast curing adhesives are used, then bonding speed is improved, but excess heat is generated creating safety hazards

Engineering Contradiction:
Improvebonding speedVSAvoidexcess heat
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The invention removes the thick adhesive sections that cause excessive heat generation during fast curing. By eliminating the need for substantial bonding material through the wedge-shaped core material design, the harmful thermal effects are extracted from the system entirely.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The wedge-shaped core material with its mounting surface acts as an intermediary between the two shell members, providing a stable bonding surface that reduces the amount of adhesive needed. This intermediary structure mediates the joining process, allowing for thinner adhesive sections that cure faster without generating excessive heat.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Strength

If conventional bonding methods are used at trailing edges, then structural connection is achieved, but handling and placement precision are reduced

Engineering Contradiction:
Improvetrailing edge connectionVSAvoidhandling and placement
Core Design Contradiction:
StrengthVSEase of operation

Solution Approach 1:

The wedge-shaped core material is pre-formed with a mounting surface portion and a trailing edge portion in the correct geometric configuration before assembly. This preliminary preparation ensures precise placement and alignment during assembly, eliminating handling difficulties associated with conventional bonding methods.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The mounting surface portion of the wedge-shaped core material is specifically designed with localized geometric properties that facilitate precise placement and stable bonding. This local optimization of the mounting surface area improves handling and placement precision without compromising the overall trailing edge connection strength.

Inventive Principle:
Principle #3Local quality

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 method enhances structural integrity at the trailing edge by reducing material weight and eliminating the need for additional adhesive, while allowing for easier handling and precise placement, thus improving safety and reducing manufacturing costs.

Implementation Method 1

infusing the one or more first dry skin layers and the wedge-shaped core material together via a resin material atop the first mold to form a first shell member

Methodology Applied
Scientific EffectResin infusion: Adhesive

Data Source

PatentEP4074493B1Method of forming a wind turbine rotor blade
Publication Date: 2025.08.20 LM WIND POWER AS
  • EP4074493B1 patent drawingFigure 1
  • EP4074493B1 patent drawingFigure 2~3
  • EP4074493B1 patent drawingFigure 4

AI summary

A method of forming a rotor blade includes positioning first dry skin layer(s) in a first mold. The method also includes placing a wedge-shaped core material having a mounting surface atop the first dry skin(s) in the first mold at a trailing edge end of the rotor blade. The method further includes infusing the first dry skin layer(s) and the core material together via a resin material to form a first shell member. The method includes applying an adhesive onto the mounting surface and then placing a second mold with a second shell member arranged therein atop the first mold containing the first shell member to form the rotor blade such that a portion of the second shell member rests atop the mounting surface. Thus, the method includes securing the shell members together via the adhesive, wherein the core material supports the trailing edge end of the rotor blade.