Showing papers on "Turbine blade published in 2022"

In-situ condition monitoring of wind turbine blades: A critical and systematic review of techniques, challenges, and futures

Abstract: Blades are critical components in wind turbines (WTs) for power generation, and condition monitoring (CM) of WT blades is a crucial and challenging issue under operating conditions. Several methods have been developed to assess blade health status, and some of them have the potential to achieve in-situ CM. Nevertheless, there is a lack of critical and comprehensive survey concerning CM techniques for operational WT blades, as well as unsolved problems and research prospects. In this paper, typical causes and types of blade damage that deserve to be considered during the running time are presented. Besides, in-situ CM techniques for WT blades are reviewed in terms of four sub-targets: damage detection, localization, classification, and evaluation. Further, the investigation and development timeline of in-situ CM methods and types of damage that have been verified to be recognizable in field tests are concluded for the first time. The paper ends with discussions on research impediments and prospects that indicate promising development tendencies.

The complex end-of-life of wind turbine blades: A review of the European context

Abstract: The recycling of glass fibre thermoset composites in general and of wind turbine blades in particular has been investigated for many years but still remains challenging. In order to provide the reader with an overview of the challenges related to the end-of-life of wind turbine blades, this review first describes the chain of processes taking place when wind turbine blades end their service life. Key elements of this value chain are presented and discussed throughout the review. These include the estimation and prediction of the volume of wind turbine blade waste, the legislation and standards framing the processes of the value chain and the technical processes transforming wind turbine blades into new valuable materials and their applications. The review highlights the need of solutions addressing the entire value chain and ends with discussing the potentials of circular economy and life cycle engineering to facilitate the implementation of sustainable solutions. To provide a holistic picture of the sustainability of these solutions, the mechanisms of social acceptance and technology perception are also discussed. • End-of-life of blade is a complex value chain made of several steps and stakeholders. • Challenges exist from the decommissioning to the reuse of blade materials. • A holistic approach is needed to implement new recycling solutions. • Economic, technical, environmental, legislation and social aspects should be considered.

Review of the Typical Damage and Damage-Detection Methods of Large Wind Turbine Blades

Abstract: With global warming and the depletion of fossil energy sources, renewable energy is gradually replacing non-renewable energy as the main energy in the future. As one of the fastest growing renewable energy sources, the safety and reliability of wind energy have been paid more and more attention. The size of modern wind turbines is becoming larger and larger. As the main component of wind turbines to capture energy, the blade is often damaged by various complex environments and irregular loads. Therefore, the health monitoring and damage identification of wind turbine blades have become a main research focus. At present, in addition to the overview of various detection methods of wind turbine blades, there is a lack of comprehensive classifications and overviews of the main damage types, damage-generation mechanisms, and basic principles of the damage-detection technology of wind turbine blades. In this paper, firstly, the common fault types of wind turbine blades, such as trailing edge cracking, lightning strike, leading edge corrosion pollution, icing, and delamination, as well as their generation mechanism, are comprehensively analyzed. Then, the basic principles and the latest research progress of the current main detection technologies, such as vision, ultrasonic, thermal imaging, vibration, acoustic emission, and so on, are comprehensively reviewed. The advantages and limitations of the various detection technologies for practical application are summarized. Finally, through a comparative analysis of the various damage-detection technologies, we try to find potential future research directions, and draw conclusions. This paper will provide a reference for understanding the mechanism behind the main damage types and the damage-detection methods of wind turbine blades. It has important reference value for further promoting practical research of wind turbine blade damage-detection technology and grasping this research direction.

Root Causes and Mechanisms of Failure of Wind Turbine Blades: Overview

Abstract: A review of the root causes and mechanisms of damage and failure to wind turbine blades is presented in this paper. In particular, the mechanisms of leading edge erosion, adhesive joint degradation, trailing edge failure, buckling and blade collapse phenomena are considered. Methods of investigation of different damage mechanisms are reviewed, including full scale testing, post-mortem analysis, incident reports, computational simulations and sub-component testing. The most endangered regions of blades include the protruding parts (tip, leading edges), tapered and transitional areas and bond lines/adhesives. Computational models of different blade damage mechanisms are discussed. The role of manufacturing defects (voids, debonding, waviness, other deviations) for the failure mechanisms of wind turbine blades is highlighted. It is concluded that the strength and durability of wind turbine blades is controlled to a large degree by the strength of adhesive joints, interfaces and thin layers (interlaminar layers, adhesives) in the blade. Possible solutions to mitigate various blade damage mechanisms are discussed.

Performance Prediction and Geometry Optimization for Application of Pump as Turbine: A Review

Abstract: Pump as Turbine (PAT) is a technically and economically effective technology to utilize small/mini/micro/pico hydropower, especially in rural areas. There are two main subjects that influence the selection and application of PAT. On the one hand, manufacturers of pumps will not provide their characteristics under the turbine mode, which requires performance prediction methods. On the other hand, PAT efficiency is always slightly lower than that of pump, which requires further geometry optimization. This literature review summarized published research studies related to performance prediction and geometry optimization, aimed at guiding for selection and optimization of PAT. Currently, there exist four categories of performance prediction methods, namely, using BEP (Best Efficiency Point), using specific speed, loss modeling, and polynomial fitting. The using BEP and loss modeling methods are based on theoretical analysis, while using specific speed and polynomial fitting methods require statistical fitting. The prediction errors of published methods are within ±10% mostly. For geometry optimization, investigations mainly focus on impeller diameter and blade geometry. The influence of impeller trimming, blade rounding, blade wrap angle, blade profile, blade number, blade trailing edge position, and guide vane number has been studied. Among published methods, the blade rounding and forward-curved impellers are the most effective and feasible techniques.

A Review on the Processing of Aero-Turbine Blade Using 3D Print Techniques

Abstract: Additive manufacturing (AM) has proven to be the preferred process over traditional processes in a wide range of industries. This review article focused on the progressive development of aero-turbine blades from conventional manufacturing processes to the additive manufacturing process. AM is known as a 3D printing process involving rapid prototyping and a layer-by-layer construction process that can develop a turbine blade with a wide variety of options to modify the turbine blade design and reduce the cost and weight compared to the conventional production mode. This article describes various AM techniques suitable for manufacturing high-temperature turbine blades such as selective laser melting, selective laser sintering, electron beam melting, laser engineering net shaping, and electron beam free form fabrication. The associated parameters of AM such as particle size and shape, powder bed density, residual stresses, porosity, and roughness are discussed here.

Multi-Objective Optimization and Optimal Airfoil Blade Selection for a Small Horizontal-Axis Wind Turbine (HAWT) for Application in Regions with Various Wind Potential

Abstract: The type of airfoil with small wind turbine blades should be selected based on the wind potential of the area in which the turbine is used. In this study, 10 low Reynolds number airfoils, namely, BW-3, E387, FX 63-137, S822, S834, SD7062, SG6040, SG6043, SG6051, and USNPS4, were selected and their performance was evaluated in a 1 kW wind turbine in terms of the power coefficient and also the startup time, by performing a multi-objective optimization study. The blade element momentum technique was utilized to perform the calculations of the power coefficient and startup time and the differential evolution algorithm was employed to carry out the optimization. The results reveal that the type of airfoil used in the turbine blade, aside from the aerodynamic performance, completely affects the turbine startup performance. The SG6043 airfoil has the highest power coefficient and the BW-3 airfoil presents the shortest startup time. The high lift-to-drag ratio of the SG6043 airfoil and the low inertia of the turbine blades fitted with the BW-3 airfoil make them suitable for operation in windy regions and areas with low wind speeds, respectively.

Fault Detection of Wind Turbine Blades Using Multi-Channel CNN

Abstract: This study utilized the multi-channel convolutional neural network (MCNN) and applied it to wind turbine blade and blade angle fault detection. The proposed approach automatically and effectively captures fault characteristics from the imported original vibration signals and identifies their state in multiple convolutional neural network (CNN) models. The result obtained from each model is sent to the output layer, which is a maximum output network (MAXNET), to compute the most accurate state. First, in terms of wind turbine blade state detection, this paper builds blade models based on the normal state and three common fault types, including blade angle anomaly, blade surface damage, and blade breakage. Vibration signals are employed for fault detection. The proposed wind turbine fault diagnosis approach adopts a triaxial vibration transducer and frame grabber to capture vibration signals and then applies the new MCNN algorithm to identify the state. The test results show that the proposed approach could deliver up to 87.8% identification accuracy for four fault types of large wind turbine blades.

Wind Turbine Blades Using Recycled Carbon Fibers: An Environmental Assessment.

Abstract: Polymers reinforced with virgin carbon fibers (VCF) are being used to make spar caps of wind turbine (WT) blades and polymers with glass fibers (GF) to make skins of the blade components. Here, we assess the life cycle environmental performance of the hybrid blades with spar caps based on VCF and the shells and shear webs based on RCF (recycled CF) composites (RCF-hybrid). The production of the WT blades and associated reinforced polymers is assumed to occur in Sweden, with their uses and end-of-life management in the European region. The functional unit is equivalent to three blades in an offshore WT with the market incumbent blades solely based on the GF composite or the hybrid option. The RCF-hybrid blades offer 12-89% better environmental performance in nine out of 10 impact categories and 6-26% better in six out of 10 impact categories. The RCF-hybrid blades exhibit optimum environmental performance when the VCF manufacturing facilities are equipped with pollution abatement systems including regenerative thermal oxidizers to reduce ammonia and hydrogen cyanide emissions; spar caps are made using VCF epoxy composites through pultrusion and resin infusion molding, and the blade scrap is mechanically recycled at the end of life. The energy and carbon payback times for the RCF-hybrid blades were found to be 5-13% lower than those of the market incumbents.