Alternative Materials, Manufacturing Processes, and Structural Designs for Large Wind Turbine Blades

Author(s):  
Dayton A. Griffin

As part of the U.S. Department of Energy’s Wind Partnerships for Advanced Component Technologies program, Global Energy Concepts LLC (GEC) has performed a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes. Fiberglass/carbon hybrid blades are identified as having a promising combination of cost, weight, stiffness and fatigue resistance. Vacuum-assisted resin transfer molding, resin film infusion, and pre-impregnated materials are identified as having benefits in reduced volatile emissions, higher fiber content, and improved laminate quality relative to the baseline wet lay-up process. Alternative structural designs are identified, including jointed configurations to facilitate transportation. Based on the study results, recommendations are developed for further evaluation and testing to verify the predicted material and structural performance.

Author(s):  
Dayton A. Griffin ◽  
Thomas D. Ashwill

As part of the U.S. Department of Energy’s Wind Partnerships for Advanced Component Technologies program, Global Energy Concepts LLC (GEC) is performing a study concerning blades for wind turbines in the multi-megawatt range. Earlier in this project constraints were identified to cost-effective scaling-up of the current commercial blade designs and manufacturing methods, and candidate innovations in composite materials, manufacturing processes and structural configurations were assessed. In the present work, preliminary structural designs are developed for hybrid carbon fiber/fiberglass blades at system ratings of 3.0 and 5.0 megawatts. Structural performance is evaluated for various arrangements of the carbon blade spar. Critical performance aspects of the carbon material and blade structure are discussed. To address the technical uncertainties identified, recommendations are made for new testing of composite coupons and blade sub-structure.


2003 ◽  
Vol 125 (4) ◽  
pp. 515-521 ◽  
Author(s):  
Dayton A. Griffin ◽  
Thomas D. Ashwill

As part of the U.S. Department of Energy’s Wind Partnerships for Advanced Component Technologies program, Global Energy Concepts LLC (GEC) is performing a study concerning blades for wind turbines in the multi-megawatt range. Earlier in this project constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods were identified, and candidate innovations in composite materials, manufacturing processes and structural configurations were assessed. In the present work, preliminary structural designs are developed for hybrid carbon fiber/fiberglass blades at system ratings of 3.0 and 5.0 MW. Structural performance is evaluated for various arrangements of the carbon blade spar, and critical performance aspects of the carbon material and blade structure are discussed. Recommendations are made for new testing of composite coupons and blade sub-structure to address the technical uncertainties identified in this work.


Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3916 ◽  
Author(s):  
Mikkel Schou Nielsen ◽  
Ivan Nikolov ◽  
Emil Krog Kruse ◽  
Jørgen Garnæs ◽  
Claus Brøndgaard Madsen

Over time, erosion of the leading edge of wind turbine blades increases the leading-edge roughness (LER). This may reduce the aerodynamic performance of the blade and hence the annual energy production of the wind turbine. As early detection is key for cost-effective maintenance, inspection methods are needed to quantify the LER of the blade. The aim of this proof-of-principle study is to determine whether high-resolution Structure-from-Motion (SfM) has the sufficient resolution and accuracy for quantitative inspection of LER. SfM provides 3D reconstruction of an object geometry using overlapping images of the object acquired with an RGB camera. Using information of the camera positions and orientations, absolute scale of the reconstruction can be achieved. Combined with a UAV platform, SfM has the potential for remote blade inspections with a reduced downtime. The tip of a decommissioned blade with an artificially enhanced erosion was used for the measurements. For validation, replica molding was used to transfer areas-of-interest to the lab for reference measurements using confocal microscopy. The SfM reconstruction resulted in a spatial resolution of 1 mm as well as a sub-mm accuracy in both the RMS surface roughness and the size of topographic features. In conclusion, high-resolution SfM demonstrated a successful quantitative reconstruction of LER.


2021 ◽  
Author(s):  
Artur Movsessian ◽  
David Garcia Cava ◽  
Dmitri Tcherniak

In recent years, Machine Learning (ML) techniques have gained popularity in Structural Health Monitoring (SHM). These have been particularly used for damage detection in a wide range of engineering applications such as wind turbine blades. The outcomes of previous research studies in this area have demonstrated the capabilities of ML for robust damage detection. However, the primary challenge facing ML in SHM is the lack of interpretability of the prediction models hindering the broader implementation of these techniques. For this purpose, this study integrates the novel Shapley Additive exPlanations (SHAP) method into a ML-based damage detection process as a tool for introducing interpretability and, thus, build evidence for reliable decision-making in SHM applications. The SHAP method is based on coalitional game theory and adds global and local interpretability to ML-based models by computing the marginal contribution of each feature. The contribution is used to understand the nature of damage indices (DIs). The applicability of the SHAP method is first demonstrated on a simple lumped mass-spring-damper system with simulated temperature variabilities. Later, the SHAP method has been evaluated on data from an in-operation V27 wind turbine with artificially introduced damage in one of its blades. The results show the relationship between the environmental and operational variabilities (EOVs) and their direct influence on the damage indices. This ultimately helps to understand the difference between false positives caused by EOVs and true positives resulting from damage in the structure.


Author(s):  
Katerin Ramirez-Tejeda ◽  
David A. Turcotte ◽  
Sarah Pike

Finding ways to manage the waste from the expected high number of wind turbine blades in need of disposal is crucial to harvest wind energy in a truly sustainable manner. Landfilling is the most cost-effective disposal method in the United States, but it imposes significant environmental impacts. Thermal, mechanical, and chemical processes allow for some energy and/or material recovery, but they also carry potential negative externalities. This article explores the main economic and environmental issues with various wind turbine blade disposal methods. We argue for the necessity of policy intervention that encourages industry to develop better technologies to make wind turbine blade disposal sustainable, both environmentally and economically. We present some of the technological initiatives being researched, such as the use of bio-derived resins and thermoplastic composites in the manufacturing process of the blades.


Fluids ◽  
2021 ◽  
Vol 6 (7) ◽  
pp. 257
Author(s):  
Samuel Mitchell ◽  
Iheanyichukwu Ogbonna ◽  
Konstantin Volkov

The design of wind turbines requires a deep insight into their complex aerodynamics, such as dynamic stall of a single airfoil and flow vortices. The calculation of the aerodynamic forces on the wind turbine blade at different angles of attack (AOAs) is a fundamental task in the design of the blades. The accurate and efficient calculation of aerodynamic forces (lift and drag) and the prediction of stall of an airfoil are challenging tasks. Computational fluid dynamics (CFD) is able to provide a better understanding of complex flows induced by the rotation of wind turbine blades. A numerical simulation is carried out to determine the aerodynamic characteristics of a single airfoil in a wide range of conditions. Reynolds-averaged Navier–Stokes (RANS) equations and large-eddy simulation (LES) results of flow over a single NACA0012 airfoil are presented in a wide range of AOAs from low lift through stall. Due to the symmetrical nature of airfoils, and also to reduce computational cost, the RANS simulation is performed in the 2D domain. However, the 3D domain is used for the LES calculations with periodical boundary conditions in the spanwise direction. The results obtained are verified and validated against experimental and computational data from previous works. The comparisons of LES and RANS results demonstrate that the RANS model considerably overpredicts the lift and drag of the airfoil at post-stall AOAs because the RANS model is not able to reproduce vorticity diffusion and the formation of the vortex. LES calculations offer good agreement with the experimental measurements.


Author(s):  
Artur Movsessian ◽  
David Garcia Cava ◽  
Dmitri Tcherniak

Abstract In recent years, Machine Learning (ML) techniques have gained popularity in Structural Health Monitoring (SHM). These have been particularly used for damage detection in a wide range of engineering applications such as wind turbine blades. The outcomes of previous research studies in this area have demonstrated the capabilities of ML for robust damage detection. However, the primary challenge facing ML in SHM is the lack of interpretability of the prediction models hindering the broader implementation of these techniques. For this purpose, this study integrates the novel Shapley Additive exPlanations (SHAP) method into a ML-based damage detection process as a tool for introducing interpretability and, thus, build evidence for reliable decision-making in SHM applications. The SHAP method is based on coalitional game theory and adds global and local interpretability to ML-based models by computing the marginal contribution of each feature. The contribution is used to understand the nature of damage indices (DIs). The applicability of the SHAP method is first demonstrated on a simple lumped mass-spring-damper system with simulated temperature variabilities. Later, the SHAP method has been evaluated on data from an in-operation V27 wind turbine with artificially introduced damage in one of its blades. The results show the relationship between the environmental and operational variabilities (EOVs) and their direct influence on the damage indices. This ultimately helps to understand the difference between false positives caused by EOVs and true positives resulting from damage in the structure.


2019 ◽  
Vol 57 (2) ◽  
pp. 45-56
Author(s):  
Mihaela Raluca Condruz ◽  
Ion Malael ◽  
Ionut Sebastian Vintila ◽  
Mihail Puscas Cernat

The paper presents the manufacturing process of advanced composite wind turbine blades designed for an experimental counter rotating vertical wind turbine (CR-VAWT). An iterative approach was used to present the manufacturing process of turbine blades starting from presentation of the turbine structure and material description as well as all manufacturing process stages. Two types of turbine blades were successfully manufactured using metallic molds and a cost-effective manufacturing technology. Based on the turbine blades obtained it can be said that the selected manufacturing process showed good results, very similar with results expected in case of using advanced technologies (i.e. autoclave technology.


Sign in / Sign up

Export Citation Format

Share Document