Wind Turbine Rotor Blade Chord Extender Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wind turbine rotor blades face design constraints that limit their size, affecting efficiency, and surface fouling degrades their aerodynamic performance over time, necessitating a means to increase chord length and maintain performance.
Innovation Solution
A chord extender is designed to be attached to the trailing edge of rotor blades, varying in shape, length, and orientation along the blade span, with stiffening ribs to enhance stiffness and counter aerodynamic loads, thereby increasing the effective chord length and lift-to-drag ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the chord length of rotor blade is increased to improve energy production and lift-to-drag ratio, then power production increases, but manufacturing and transportation constraints are violated
Solution Approach 1:
The blade is divided into two functional parts: the original blade structure and the separately attachable chord extender. This segmentation allows the extender to be manufactured and transported independently, then assembled onto the blade to achieve increased chord length without violating manufacturing and transportation constraints.
Solution Approach 2:
The chord extender is attached at the trailing edge of the blade, extending the chord length in the chordwise direction. This dimensional extension approach allows increasing the effective chord length without changing the overall blade span or root structure, thereby avoiding manufacturing and transportation constraints.
2Productivity
If the chord length of rotor blade is increased to improve aerodynamic performance, then lift-to-drag ratio increases, but structural integrity under aerodynamic loads becomes compromised
Solution Approach 1:
The chord extender incorporates stiffening ribs that provide localized structural reinforcement at the trailing edge region. This local quality enhancement ensures that the extended chord section has sufficient stiffness and strength to withstand aerodynamic loads, maintaining structural integrity while improving aerodynamic performance.
Solution Approach 2:
The chord extender is constructed using composite material structures with stiffening ribs, combining multiple materials and structural elements to achieve both the aerodynamic benefits of extended chord length and the structural strength required to resist aerodynamic loads.
3Productivity
If surface fouling occurs on rotor blade, then aerodynamic performance degrades, but no immediate solution is provided to restore performance
Solution Approach 1:
The chord extender can be removed and replaced independently from the main blade structure. When surface fouling degrades performance, the extender can be discarded (removed) and a clean replacement extender can be installed, restoring aerodynamic performance without requiring removal or cleaning of the entire blade.
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 chord extender enhances energy capturing capabilities, increasing lift and axial induction, leading to improved rotor torque and annual energy production while maintaining structural integrity under aerodynamic loads.
Implementation Method 1
an increased chord length may result in an increased lift-to-drag ratio for a rotor blade
Implementation Method 2
with stiffening ribs to enhance stiffness and counter aerodynamic loads
Implementation Method 3
The rotor blades capture kinetic energy of wind using known foil principles
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A rotor blade assembly 100 for a wind turbine 10 may generally include a rotor blade 22 extending lengthwise between a root 108 and a tip 110. The rotor blade 22 may include a pressure side 114 and a suction side 116 extending between a leading edge 118 and a trailing edge 120. Additionally, the rotor blade assembly 100 may include a chord extender 104, 106 having an attachment portion 148 coupled to at least of the pressure side 114 or the suction side 116 and an extension portion 150 extending outwardly from the attachment portion 148 beyond the trailing edge. The extension portion 150 may extend chordwise between a first end disposed adjacent to the trailing edge 120 and a second end disposed opposite the first end. The extension portion 150 may include a surface defined between the first and second ends. The extension portion 150 may further include at least one stiffening rib 172 projecting outwardly from the surface.