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21 novembre 2019

Éolien en mer : 10 % de la taxe seront affectés à l'Office français de la biodiversité

Éolien en mer : 10 % de la taxe seront affectés à l'Office français de la biodiversité

Les députés ont adopté, le 15 novembre, un amendement au projet de loi de finances pour 2020 (PLF 2020) qui affecte 10 % de la taxe sur les éoliennes en mer à l'Office français de la biodiversité (OFB). Ce nouvel établissement public doit naître, le 1er janvier prochain, de la fusion de l'Agence française pour la biodiversité (AFB) et de l'Office national de la chasse et de la faune sauvage (ONCFS). « Affecter ainsi 10 % du produit de la taxe sur l'éolien en mer à l'OFB...

20 novembre 2019

USRE47696E1 - Profil aérodynamique composite - Google Brevets

USRE47696E1 - Profil aérodynamique composite - Google Brevets

A composite aerofoil, the aerofoil having a leading edge, a trailing edge a pressure side and a suction side and comprising an outer erosion protection layer along one or both of the pressure side or suction side, a structural core having a plurality of resin impregnated plies of unidirectional fibers, and between the outer erosion protection layer and the structural core a woven composite impregnated with a resin having a modulus of elasticity greater lower than that of the resin impregnating the plies in the structural core.


18 novembre 2019

Vieillissement physique des matériaux polymères : Dossier complet | Techniques de l’Ingénieur

Vieillissement physique des matériaux polymères : Dossier complet | Techniques de l’Ingénieur

Le vieillissement d’un matériau est caractérisé par une évolution lente et irréversible suite à la combinaison de sollicitations mécaniques, d’interactions avec son environnement et de sa propre instabilité. Cet article s’intéresse plus spécifiquement aux phénomènes de vieillissement physique des matériaux polymères. Deux mécanismes principaux sont en jeu, les processus de relaxation structurale non impactés par l’environnement et les processus d’absorption-désorption lorsque l’environnement contient une espèce miscible au polymère.


Vieillissement des composites - Évolution des propriétés et modélisation : Dossier complet | Techniques de l’Ingénieur

Vieillissement des composites - Évolution des propriétés et modélisation : Dossier complet | Techniques de l’Ingénieur

Cet article présente une revue détaillée des aspects phénoménologiques du vieillissement des matériaux composites à matrice organique, abordée à travers la présentation d'observations expérimentales, résultats de mesures et simulations numériques. Il se focalise tout d'abord sur la modélisation du vieillissement, pour se consacrer ensuite à la présentation d'un certain nombre d'exemples et cas d'études concernant les couplages thermomécanique, diffuso-mécanique, thermo-chimico-mécanique qui apparaissent lors du vieillissement (thermomécanique, humide et thermo-oxydant) de matériaux composites pour applications aéronautiques et aérospatiales.


17 novembre 2019

End-of-life Options for Composite Material Wind Turbine Blades: Recover, Repurpose or Reuse? — Re-Wind

End-of-life Options for Composite Material Wind Turbine Blades: Recover, Repurpose or Reuse? — Re-Wind

The technical and commercial success of wind energy has resulted in c. 600 GW of capacity being deployed around the world. Wind turbines have a typical operational lifetime of 20-25 years, therefore a large number of wind turbines will be decommissioned in the coming decades. This will lead to a large volume of composite material waste from end-of-life blades. In this paper, repurposing is proposed as an environmentally, socially and economically sustainable end-of-life option for composite material wind turbine blades. Repurposing is preferable to materials recovery, waste-to-energy or landfilling within the circular economy paradigm, and may offer additional social benefits over these other options. A methodology is proposed to assess the environmental, social and economic sustainability of repurposing solutions for end-of-life wind turbine blades.

Leahy, P.G., 2019, “End-of-life Options for Composite Material Wind Turbine Blades: Recover, Repurpose or Reuse?” 14th SWEDES Conference, Dubrovnik, CROATIA, Oct 1-6, 2019


14 novembre 2019

Performance Analysis of Composite Helicopter Blade Using Synergistic Damage Mechanics Approach | AIAA Journal

Performance Analysis of Composite Helicopter Blade Using Synergistic Damage Mechanics Approach | AIAA Journal

The damage behavior of a helicopter rotor blade made of carbon fiber polymer composite has been numerically investigated using a synergistic damage mechanics (SDM) model. Laminates of the quasi-isotropic stacking sequence [0/90/45/+45]s have been considered in this study. The simulations were performed, corresponding to a hovering condition and for a range of the angles of attack and rotational speeds of the blade. The aerodynamic and centrifugal loads due to different angles of attack and rotational speeds have been computed by using fluid dynamics simulations. A structural analysis was then performed using the aerodynamic loads. Using the SDM model, the matrix crack density and crack multiplication were evaluated to predict the damage initiation site and maximum crack density occurring in the plies of the laminate under the operational conditions. It was observed that maximum crack appeared in the blade at extreme operational conditions; among the different plies, a 45deg ply was cracked by the maximum amount. A crack density of around 0.9  crack/mm was predicted in the 45deg ply at an operational condition with a 500 rpm blade rotation and an 18 deg angle of attack of the blade. The present study demonstrates application of the progressive damage modeling in designing a composite helicopter blade by considering its performance parameters.

8 novembre 2019

Éolien en mer : le débat public pour de nouveaux parcs en Normandie s'ouvre le 15 novembre

Éolien en mer : le débat public pour de nouveaux parcs en Normandie s'ouvre le 15 novembre

La Commission nationale du débat public (CNDP) organise, du 15 novembre 2019 au 15 mai 2020, un débat public sur le futur appel d'offres de l'État pour construire un nouveau parc éolien d'une puissance d'1 GW au large des côtes normandes. Elle a été saisie par le ministère de la Transition écologique pour l'organiser en amont et en parallèle de la procédure de mise en concurrence des candidats, ce qui est une première. Les débats ont, jusqu'ici, été menés une fois les projets attribués.


GE Renewable Energy inaugure à Cherbourg son usine de production de pales géantes d'éoliennes - L'Usine Energie

GE Renewable Energy inaugure à Cherbourg son usine de production de pales géantes d'éoliennes - L'Usine Energie

L’usine de Cherbourg inaugurée mercredi 6 novembre par LM Wind Power et GE Renewable Energy fabriquera les plus grandes pales d’éoliennes du marché (107 mètres de long) pour des parcs éoliens britanniques et américains. Cette usine, qui emploie 260 salariés, représente un investissement de 100 millions d’euros.


6 novembre 2019

Dieselgate : une action collective vise Renault

Dieselgate : une action collective vise Renault

Une action collective est engagée contre Renault. Objectif : obtenir une indemnisation pour les propriétaires de véhicules figurant parmi les plus polluants. Si Renault refuse de négocier, l'affaire pourrait être portée devant les tribunaux.


J. Compos. Sci. | Free Full-Text | A Survey of Scrutinizing Delaminated Composites via Various Categories of Sensing Apparatus

J. Compos. Sci. | Free Full-Text | A Survey of Scrutinizing Delaminated Composites via Various Categories of Sensing Apparatus

Scrutinizing delaminated composites is extensively conducted based on measurements of various types of nondestructive sensing apparatus, classified herein as systems of thermographic inspection, piezoelectric inspection, optical interferometric inspection, electromagnetic testing, ultrasonic testing, and visual testing. The development of the subject has been reviewed during 2000–2017. Not only does the substantial corresponding literature strongly indicates numerous increasing industrial demand for composites, including carbon fiber-reinforced polymer, glass fiber-reinforced polymer, and fiber-reinforced metal laminate, but also the significant potential of composites to delaminate when subjected particularly to impact, machining operation or manufacturing imperfections. Conducting a study on the corresponding literature, the subject of delamination inspection within composites is found to be a dynamic, mature field, while lacking a thorough literature review. Therefore, the present study addresses the mentioned gap regarding various sensation systems utilized so as to detect internal anomalies in composites for the review arrangement. To that end, the literature inclusion in terms of citation times is electronically adopted associated with an appropriate combination of keywords. The study may be considered as a comprehensive, up-to-date review covering all delamination inspection techniques founded on sensation systems, thus benefiting the readers with information in an organized configuration. View Full-Text


Analysis on Damage Characteristics of CFRP Under Impulse Current | SpringerLink

Analysis on Damage Characteristics of CFRP Under Impulse Current | SpringerLink

As the light weight and high mechanical strength, the carbon fiber composites are being used more and more in aerospace industry. However, the conductivity of CFRP is much smaller than that of metal. When lightning strikes to CFRP, it will generate a lot of Joule heat and cause serious damage. Therefore, it is necessary to study the lighting damage characteristics of CFRP. In this paper, the experimental models of carbon fiber and epoxy resin were established, and the dielectric properties, temperature rise performance, and lightning current damage of CFRP were also investigated. Results show that the dielectric constant of CFRP is decreased at the frequency above 300 Hz and the volume resistivity is almost same within the frequency range of 0.1–106 Hz. The thermal damage of the sample started from the carbon fiber bundle and then transferred heat to the whole composite material. When carbon fabric composite was damaged by impulse current, samples broke along the direction of carbon fiber bundle and the severity of samples damage correlates with the mass fraction of the carbon fiber bundle. According to experimental observation, temperature of carbon fiber was rapid rise during the impulse current process and causes the surrounding epoxy resin decompose and vaporize.


Damage detection techniques for wind turbine blades: A review - ScienceDirect

Damage detection techniques for wind turbine blades: A review - ScienceDirect

Blades play a vital role in wind turbine system performances. However, they are susceptible to damage arising from complex and irregular loading or even cause catastrophic collapse, and they are expensive to maintain. Defects or damages on wind turbine blades (WTBs) not only reduce the lifespan and power generation efficiency of the wind turbine, but also increase monitoring errors, safety risks and maintenance costs......

5 novembre 2019

PPA : France Énergie Éolienne publie un contrat standard

PPA : France Énergie Éolienne publie un contrat standard

Le syndicat France Énergie Éolienne (FEE) publie un modèle pour les contrats de gré à gré (Corporate PPA - Powered purchase agreement) qui fixent les conditions de rachat direct d'électricité renouvelable à un producteur par une entreprise. Élaboré après un an de réflexion au sein d'un groupe de travail réunissant toutes les parties prenantes (producteurs, consommateurs, prêteurs, investisseurs, cabinets de conseils, avocats, fiscalistes…), ce contrat standard est mis à disposition de tous les...

30 octobre 2019

Damage mechanism of wind turbine blade under the impact of lightning induced arcs: Journal of Renewable and Sustainable Energy: Vol 11, No 5

Damage mechanism of wind turbine blade under the impact of lightning induced arcs: Journal of Renewable and Sustainable Energy: Vol 11, No 5: Journal of Renewable and Sustainable Energy 11, 053306 (2019);  Minhao Zhang1, Qingmin Li1, Hongbo Li1, Wanshui Yu1, Zixin Guo1, and Wah Hoon

It is not clear for the damage mechanism of the blade structure under the effect of the lightning strike arc. In this paper, the damage characteristics of blades under the effect of an lightning arc are obtained by the impulse large current experiment....

Natural Fibers: Applications | IntechOpen

Natural Fibers: Applications | IntechOpen

Fibers derived from bio-based sources such as vegetables and animal origin are termed as natural fibers. This definition includes all natural cellulosic fibers (cotton, jute, sisal, coir, flax, hemp, abaca, ramie, etc.) and protein-based fibers such as wool and silk. There are also man-made cellulose fibers (e.g., viscose rayon and cellulose acetate) that are produced with chemical procedures from pulped wood or other sources (cotton, bamboo).