Wind Turbine Blade Root Assembly with Offset Bolt Centerlines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increasing loads on wind turbine blades due to longer blades lead to high strain and susceptibility to failure in existing root assemblies, particularly those with staggered bolt configurations, necessitating stronger roots but limited by space constraints.
Innovation Solution
A root assembly design with offset centerlines for bolts or root inserts, shifting them away from the thickness center, equalizing strain profiles and optimizing bolt placement to enhance root capacity without increasing diameter, using fiber composite materials and specific geometric configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a large number of bolts and bushings or inserts are provided in the root assembly to resist high loads, then the load-bearing capacity is improved, but the space for bolts on a common circumference is limited and the complexity of the root assembly increases
Solution Approach 1:
The patent transitions from a conventional single-plane bolt arrangement to a three-dimensional staggered configuration where bolts are distributed across multiple planes at different radial distances from the centerline. This spatial dimensionality change allows more bolts to be accommodated within the same circumferential space, increasing load-bearing capacity without proportionally increasing complexity.
Solution Approach 2:
The root assembly is segmented into multiple bolt planes, with each plane containing a subset of bolts at specific radial positions. This segmentation allows the load to be distributed across multiple discrete locations in space, enabling the system to handle higher loads while maintaining manageable complexity through modular arrangement.
2Quantity of substance
If a staggered configuration of bolts is provided to increase root capacity, then the number of T-bolts or root inserts is improved, but the root portions experience large strain and are susceptible to failure
Solution Approach 1:
Different bolt planes are positioned at different radial distances from the centerline, creating local variations in strain distribution. Bolts in outer planes experience different stress levels than those in inner planes, allowing the structure to optimize strain distribution locally across the root portion, thereby reducing peak strains and improving reliability.
3Strength
If the root assembly is designed with offset centerlines for bolts, then the strain profile through the thickness is equalized and root capacity is increased, but the manufacturing precision requirements increase
Solution Approach 1:
The bolt arrangement employs asymmetric positioning with offset centerlines and unequal radial distances from the root portion centerline. This asymmetric configuration equalizes the strain profile through the thickness of the root portion by deliberately creating non-uniform bolt distribution, optimizing structural performance while the offset distances are designed to be within manufacturable tolerances.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
Root assembly of a wind turbine blade for a wind turbine, wind turbine blade and wind turbine The invention relates to a root assembly (20) of a wind turbine blade (5) for a wind turbine (1). The invention further relates to a wind turbine blade (5) comprising the root assembly (20) and a wind turbine (1) comprising the wind turbine blade (5).