Solid particle erosion of graphene-based coatings - ScienceDirect

Solid particle erosion of graphene-based coatings - ScienceDirect

Solid particle erosion experiments have been conducted to study the erosion behavior of multiple graphene-based coatings. In this paper, the effects of three factors on the erosion resistance have been investigated: (1) The effect of using graphene-based coatings (2) The effect of using single and multilayer coatings with alternating graphene and polyurethane layers, (3) The effects of angles of attack and erosion duration on the single and multilayer graphene coatings. The investigation also explored the coating surface quality, adhesion, and coating hardness. Finally, two parameters were used to evaluate the efficiency of the coating systems: Material removal and the depth of the erosion scar.....

Wind Turbine Blade Aerodynamic Efficiency Enhancement Efforts-A Compiled Review

Wind Turbine Blade Aerodynamic Efficiency Enhancement Efforts-A Compiled Review PDF

S Gomathinayagam, FD General - NATIONAL INSTITUTE OF WIND ENERGY, 2021

Performance estimation and redesign of horizontal axis wind turbine (HAWT) blade - ScienceDirect

Performance estimation and redesign of horizontal axis wind turbine (HAWT) blade - ScienceDirect

The present global energy crisis has pushed the human race to its limit in search of alternative sources of energy. Wind turbine technology has seen continuous developments ever since the humankind has been on the lookout for harnessing the wind energy. The modern design analysis tools and the emergence of new materials have enabled the development of state-of-the-art wind turbines. The main power-producing component in the turbine is none other than the blade itself which has undergone a major design improvement in the recent past.....

Leading edge erosion of coated wind turbine blades: Review of coating life models - ScienceDirect

Leading edge erosion of coated wind turbine blades: Review of coating life models - ScienceDirect

Erosion of the leading edge of wind turbine blades by droplet impingement wear, reduces blade aerodynamic efficiency and power output. Eventually, it compromises the integrity of blade surfaces. Elastomeric coatings are currently used for erosion resistance, yet the life of such coatings cannot be predicted accurately. This review paper gives an overview of experimentally validated erosion model blocks that can be used to predict the life of the leading edge of coated wind turbine blades. From the reviewed work it is concluded that surface fatigue, as nucleating wear mechanism for erosion damage, can explain erosive wear and failure of the coatings. An engineering approach to surface fatigue, using the Palmgren–Miner rule for cumulative damage, allows for the construction of a rain erosion incubation period equation. ......

Physique du moulage des composites structuraux - Aspects théoriques : Dossier complet | Techniques de l’Ingénieur

Physique du moulage des composites structuraux - Aspects théoriques : Dossier complet | Techniques de l’Ingénieur

Matériaux extrêmement polyvalents, les composites à matrice polymère sont façonnables selon l’application et les propriétés recherchées. Le mode d’élaboration s’avère donc extrêmement déterminant dans la chaîne de conception, puisqu’il détermine les performances du composite. Cet article analyse les différents phénomènes mis en jeu dans les technologies de fabrication des composites avancés. Il en présente des modèles descriptifs découlant des lois de conservation (masse, énergie) et des lois constitutives (viscosité, réactivité, contraintes mécaniques…).

Recycling of thermosetting composites for wind blade application - ScienceDirect

Recycling of thermosetting composites for wind blade application - ScienceDirect

It is well known that wind energy could represent a promising solution to the continuous increase of energy demand in the modern society. At the end of 2016 the European wind power amounted to 153.7 GW, distributed on 77000 wind turbines and corresponding to the 10.4% of the electrical energy supplied. Considering the EU program to increase the renewable energy share to 27% by 2030, the key role of the wind energy in the next decade is clear. As the number of wind towers that will be dismantled in the next years will continuously increase, the development of sustainable practices to dispose of these plants at the end of their life is of utmost importance......

Structural design and optimization of a series of 13.2 MW downwind rotors - Shulong Yao, Mayank Chetan, D Todd Griffith, 2021

Structural design and optimization of a series of 13.2 MW downwind rotors - Shulong Yao, Mayank Chetan, D Todd Griffith, 2021

The quest for reduced LCOE has driven significant growth in wind turbine size. A key question to enable larger rotor designs is how to configure and optimize structural designs to constrain blade mass and cost while satisfying a growing set of challenging structural design requirements. In this paper, we investigate the performance of a series of three two-bladed downwind rotors with different blade lengths (104.3-m, 122.9-m, and 143.4-m) all rated at 13.2 MW. The primary goals are to achieve 25% rotor mass and 25% LCOE reduction. A comparative analysis of the structural performance and economics of this family rotors is presented. To further explore optimization opportunities for large rotors, we present new results in a root and spar cap design optimization. In summary, we present structural design solutions that achieve 25% rotor mass reduction in a SUMR13i design (104.3-m) and 25% LCOE reduction in a SUMR13C design (143.4-m).

LEADING EDGE EROSION OF WIND TURBINE BLADES: Understanding, prevention and protection - ScienceDirect

LEADING EDGE EROSION OF WIND TURBINE BLADES: Understanding, prevention and protection - ScienceDirect

Surface erosion of wind turbine blades is one of rather critical problems of the wind energy development. In this overview paper, recent studies in the mechanisms, modelling and possibilities of preventing the surface erosion of wind turbine blades are discussed. Latest research in the area of leading edge erosion (LEE) from different viewpoints, based on meteorology, aerodynamics, materials science, computational mechanics are summarized. Technologies of experimental testing of anti-erosion coatings, effect of leading edge erosion on aerodynamics of wind turbines, roughness and its evolution are discussed, as well as meteorological aspects, parameters and characteristics of precipitation, possibilities of prediction of rain and hail and regional differences. Further, computational models of LEE and directions of the development of anti-erosion coatings are presented.

Carbon Fiber Composites | SpringerLink

Carbon Fiber Composites | SpringerLink

Composites are a group of materials that mainly constitutes metals, ceramics, and/or polymers in order to improve the composite properties. Usually, some stiffer, stronger materials are used as reinforcing agents in the composite matrix to enhance the mechanical and thermal behavior of the composite materials. Carbon fibers are the major load-bearing components in most of the composites.

Coatings | Free Full-Text | Damage Mechanism Based Approach to the Structural Health Monitoring of Wind Turbine Blades

Coatings | Free Full-Text | Damage Mechanism Based Approach to the Structural Health Monitoring of Wind Turbine Blades

A damage mechanism based approach to the structural health monitoring of wind turbine blades is formulated. Typical physical mechanisms of wind turbine blade degradation, including surface erosion, adhesive fatigue, laminate cracking and in some cases compressive kinking and failure are reviewed. Examples of a local, damage mechanism based approach to the structural health monitoring of wind turbine blades are demonstrated, including the monitoring of leading edge erosion of wind turbine blades, adhesive bond failure, plydrop delamination, static and dynamic plydrop tests, and bolt and laminate fatigue. The examples demonstrate the possibilities of monitoring specific damage mechanisms, and specific localizations of wind turbine blades. View Full-Text

Process Development and Characterization of Novel VARTM Fiber Reinforced Thermoplastic Composites - Webthesis

Process Development and Characterization of Novel VARTM Fiber Reinforced Thermoplastic Composites - Webthesis

Fiber reinforced plastic (FRP) composite materials offer numerous advantages compared to traditional materials, like very low density, very high strength-to-weight ratio, higher fatigue resistance and better corrosion resistance. Nevertheless, their utilization in the automotive sector has been limited mainly in the design of race, high performance or luxury cars. In fact, despite their great advantages, employing FRP materials in vehicles components is more expensive than utilizing common materials like steels and it is not economically feasible for mass productions. Therefore, a fundamental aspect for increasing the utilization of FRP in the automotive sector is the reduction of the cost of raw materials and manufacturing processes. Another important aspect in the modern engineering is the possibility of recycling the materials. Nowadays, most of the FRP composites produced make use of thermosetting resins matrices that cannot be recycled. The objective of the thesis was investigating the use of an innovative thermoplastic resin for manufacturing glass fiber reinforced plastic (GFRP) panels through the vacuum assisted resin transfer molding (VARTM) process....

Durability enhancement of low ice adhesion polymeric coatings - ScienceDirect

Durability enhancement of low ice adhesion polymeric coatings - ScienceDirect

Icephobic performance of low-ice adhesion polymeric coatings has been studied intensively for passive ice protection. However, limited efforts were conducted to identify strategies for enhancing the durability of the coatings to maintain low ice adhesion after erosion impact. In this work, we developed and investigated several polyurethane-based nanocomposite and fibre-reinforced coatings to understand the deteriorating behaviour of the coatings under rigorous impinging erosion tests and the subsequent impact on ice adhesion. The inclusion of fillers resulted in up to 38 points increase in Shore hardness relative to the pristine PU coatings......

A Critical Review on the Structural Health Monitoring Methods of the Composite Wind Turbine Blades | SpringerLink

A Critical Review on the Structural Health Monitoring Methods of the Composite Wind Turbine Blades | SpringerLink

With increasing turbine size, monitoring of blades becomes increasingly important, in order to prevent catastrophic damages and unnecessary maintenance, minimize the downtime and labor cost and improving the safety issues and reliability. The present work provides a review and classification of various structural health monitoring (SHM) methods as strain measurement utilizing optical fiber sensors and Fiber Bragg Gratings (FBG’s), active/passive acoustic emission method, vibration‒based method, thermal imaging method and ultrasonic methods, based on the recent investigations and promising novel techniques.....

Durability enhancement of low ice adhesion polymeric coatings - ScienceDirect

Durability enhancement of low ice adhesion polymeric coatings - ScienceDirect: 

Icephobic performance of low-ice adhesion polymeric coatings has been studied intensively for passive ice protection. However, limited efforts were conducted to identify strategies for enhancing the durability of the coatings to maintain low ice adhesion after erosion impact. In this work, we developed and investigated several polyurethane-based nanocomposite and fibre-reinforced coatings to understand the deteriorating behaviour of the coatings under rigorous impinging erosion tests and the subsequent impact on ice adhesion.

Viscoélasticité non linéaire des polymères fondus : Dossier complet | Techniques de l’Ingénieur

Viscoélasticité non linéaire des polymères fondus : Dossier complet | Techniques de l’Ingénieur

L'article donne un panorama des connaissances sur le comportement viscoélastique non linéaire des polymères fondus plus particulièrement en cisaillement et en élongation uniaxiale. Les rhéomètres utilisés pour caractériser la viscoélasticité non linéaire sont présentés ainsi que les fonctions rhéologiques les plus communément utilisées et leur lien avec la structure des polymères. Des exemples d'applications au choix des matériaux pour les procédés de mise en oeuvre des matières plastiques sont donnés. Enfin une introduction aux concepts, qui sont à l'origine des modèles et des équations constitutives utilisées pour la simulation numérique des écoulements des polymères fondus, est proposée.