Wind Turbine Blade Trailing Edge Sharp Corner Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wind turbine blades face challenges in manufacturing the trailing edge section, where a non-zero thickness is necessary for structural integrity but can compromise aerodynamic efficiency due to resin-rich corner areas and rounded transitions that impede flow separation.
Innovation Solution
A blade design with a truncated radius at the corner between the pressure side and trailing edge sections, featuring a sharp transition point where the tangents of these sections do not coincide, enhancing aerodynamic lift and preventing premature flow separation while maintaining ease of manufacture by avoiding structurally weak resin-rich areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the trailing edge thickness is reduced to minimize aerodynamic drag, then aerodynamic efficiency is improved, but structural integrity is compromised
Solution Approach 1:
The invention applies different geometric characteristics to different parts of the airfoil: a sharp corner at the trailing edge for aerodynamic efficiency, while maintaining adequate thickness in critical structural regions. This local differentiation allows the blade to achieve both low drag and sufficient strength.
Solution Approach 2:
Instead of rounding the corner to ensure structural integrity (conventional approach), the invention inverts the approach by creating a sharp corner and using alternative structural reinforcement methods, thereby prioritizing aerodynamic performance while maintaining strength through different means.
2Reliability
If a rounded corner is provided at the trailing edge to avoid resin rich areas, then manufacturing reliability is improved, but aerodynamic performance is compromised
Solution Approach 1:
The invention segments the corner region into distinct functional zones: a sharp outer corner for aerodynamic performance and an internal structural reinforcement zone for manufacturing reliability. This segmentation allows each zone to optimize for its specific function without compromising the other.
Solution Approach 2:
The sharp corner geometry is applied locally at the trailing edge surface for aerodynamic efficiency, while internal structural features are provided locally at the corner region to ensure manufacturing reliability and avoid resin rich areas, without requiring a rounded external geometry.
3Loss of energy
If a sharp corner is created at the transition point to improve aerodynamic efficiency, then aerodynamic performance is improved, but manufacturing difficulty increases
Solution Approach 1:
The mold is segmented into multiple sections that can independently form different parts of the airfoil geometry. This segmentation allows the sharp corner to be formed by the precise alignment of mold sections rather than requiring complex single-piece mold machining, thereby maintaining manufacturing ease.
Solution Approach 2:
Instead of using a rounded corner to simplify mold design (conventional approach), the invention inverts the approach by using a sharp corner formed through precise mold section alignment, thereby prioritizing aerodynamic performance while managing manufacturing complexity through modular mold design.
Data Source
AI summary
A blade for a wind turbine defines an airfoil with a leading edge section and a trailing edge section, notably a flat-back trailing edge. A rounded connecting section interconnects a pressure side section of the airfoil and the trailing edge section. The rounded connecting section attaches to the pressure side section at a transition point, in which the pressure side section's tangent does not coincide with the rounded connecting section's tangent, so that the outer surface of the airfoil has a sharp corner at said transition point. The truncated radius, i.e. geometrical discontinuity, thus formed at the transition between the pressure side section and the trailing edge section increases the aerodynamically effective surface of the pressure side and enables forced and hence controlled flow separation without compromising ease of manufacture and structural stability of a fiber-reinforced structure making up a shell of the blade.