Components and structures working in the marine environment are exposed to high stresses attributable to the action of wind, waves, and tides. Moreover, they have to face hostile and severe environmental conditions during their lifetime, being placed in the splash zone if not even submerged in saltwater. The application of polymer composites in marine systems has been the focus of intensive studies in the last decades, highlighting potential benefits given by the replacement of several components, such as ship hulls, propeller blades, wind, and tidal turbine blades, to cite but a few. The present paper reports the latest advances in this area, addressing the applications of advanced composites in ships and ship components, offshore oil and gas composites, marine renewable energy and underwater repairing.
14 janvier 2020
JMSE | Free Full-Text | Marine Application of Fiber Reinforced Composites: A Review
JMSE | Free Full-Text | Marine Application of Fiber Reinforced Composites: A Review
Components and structures working in the marine environment are exposed to high stresses attributable to the action of wind, waves, and tides. Moreover, they have to face hostile and severe environmental conditions during their lifetime, being placed in the splash zone if not even submerged in saltwater. The application of polymer composites in marine systems has been the focus of intensive studies in the last decades, highlighting potential benefits given by the replacement of several components, such as ship hulls, propeller blades, wind, and tidal turbine blades, to cite but a few. The present paper reports the latest advances in this area, addressing the applications of advanced composites in ships and ship components, offshore oil and gas composites, marine renewable energy and underwater repairing.
Components and structures working in the marine environment are exposed to high stresses attributable to the action of wind, waves, and tides. Moreover, they have to face hostile and severe environmental conditions during their lifetime, being placed in the splash zone if not even submerged in saltwater. The application of polymer composites in marine systems has been the focus of intensive studies in the last decades, highlighting potential benefits given by the replacement of several components, such as ship hulls, propeller blades, wind, and tidal turbine blades, to cite but a few. The present paper reports the latest advances in this area, addressing the applications of advanced composites in ships and ship components, offshore oil and gas composites, marine renewable energy and underwater repairing.
Applied Sciences | Free Full-Text | A Quantitative Study on the Void Defects Evolving into Damage in Wind Turbine Blade Based on Internal Energy Storage
Applied Sciences | Free Full-Text | A Quantitative Study on the Void Defects Evolving into Damage in Wind Turbine Blade Based on Internal Energy Storage
As manufacturing defects, voids in wind turbine blades may cause damage under fatigue loads. In this paper, the internal energy storage is used as an indicator to identify the critical moment when a defect evolves into damage. The heat transfer equation of composites material containing void defects is derived based upon the theory of the thermodynamics of irreversible processes. In order to obtain the numerical calculation model of the internal energy storage of the evolving process, the thermal conductivity along the transverse direction is homogenized as the temperature date along this direction is acquired by a thermal camera. Specimens with different void fractions are tested with infrared thermal imaging under fatigue load, during which the stress, strain and temperature data are acquired to establish the curve of internal energy storage against the fatigue cycle. This relationship curve can be used to identify the critical moment when void defects evolve into damage. The feasibility of this method is proven by microscopic observation.
As manufacturing defects, voids in wind turbine blades may cause damage under fatigue loads. In this paper, the internal energy storage is used as an indicator to identify the critical moment when a defect evolves into damage. The heat transfer equation of composites material containing void defects is derived based upon the theory of the thermodynamics of irreversible processes. In order to obtain the numerical calculation model of the internal energy storage of the evolving process, the thermal conductivity along the transverse direction is homogenized as the temperature date along this direction is acquired by a thermal camera. Specimens with different void fractions are tested with infrared thermal imaging under fatigue load, during which the stress, strain and temperature data are acquired to establish the curve of internal energy storage against the fatigue cycle. This relationship curve can be used to identify the critical moment when void defects evolve into damage. The feasibility of this method is proven by microscopic observation.
8 janvier 2020
Hydrogène : matinée d'information sur les opportunités de financement 2020 - Horizon 2020
Hydrogène : matinée d'information sur les opportunités de financement 2020 - Horizon 2020
une matinée d’information sur les opportunités de financement des appels 2020 de la FCH2 JU et des appels Connecting Europe Facility (C.E.F.) se tiendra le 5 février 2020 à Paris (Parc Floral).
une matinée d’information sur les opportunités de financement des appels 2020 de la FCH2 JU et des appels Connecting Europe Facility (C.E.F.) se tiendra le 5 février 2020 à Paris (Parc Floral).
NEC reste n°1 mondial de la reconnaissance faciale - France-Diplomatie - Ministère de l’Europe et des Affaires étrangères
NEC reste n°1 mondial de la reconnaissance faciale - France-Diplomatie - Ministère de l’Europe et des Affaires étrangères
NeoFace, la technologie de reconnaissance faciale développée par la société Japonaise NEC se classe première au test annuel réalisé par l’institut américain NIST (National Institute of Standards and Technology)
NeoFace, la technologie de reconnaissance faciale développée par la société Japonaise NEC se classe première au test annuel réalisé par l’institut américain NIST (National Institute of Standards and Technology)
Aperçu du marché HSR Composites mondial 2019-2026 | AIM Aviation, Dartford Composites, FDC Composites, Gurit Holding, Hexcel – Journal l'Action Régionale
Aperçu du marché HSR Composites mondial 2019-2026 | AIM Aviation, Dartford Composites, FDC Composites, Gurit Holding, Hexcel – Journal l'Action Régionale
Selon le rapport, le marché HSR Composites mondial devrait afficher une croissance rapide représentée par un CAGR de XX% au cours de la période 2019-2026. Le marché mondial des aliments comprend une analyse complète du marché des aliments montrant la situation la plus récente du marché. Il prévoit une croissance de la taille et de la part de marché au cours de la période de prévision. Le rapport comprend la mise en place commerciale énergique de l’aperçu du marché HSR Composites ainsi que la vue d’ensemble des principaux acteurs du marché HSR Composites.
Selon le rapport, le marché HSR Composites mondial devrait afficher une croissance rapide représentée par un CAGR de XX% au cours de la période 2019-2026. Le marché mondial des aliments comprend une analyse complète du marché des aliments montrant la situation la plus récente du marché. Il prévoit une croissance de la taille et de la part de marché au cours de la période de prévision. Le rapport comprend la mise en place commerciale énergique de l’aperçu du marché HSR Composites ainsi que la vue d’ensemble des principaux acteurs du marché HSR Composites.
7 janvier 2020
Strain measurement and stress analysis in the vicinity of a Fiber Bragg grating sensor embedded in a composite material - ScienceDirect
Strain measurement and stress analysis in the vicinity of a Fiber Bragg grating sensor embedded in a composite material - ScienceDirect
The paper presents the results of a numerical analysis of the stresses in a polymer composite material (PCM) in the vicinity of an optical fiber embedded in the material, and the results from estimating the reliability of the strain values calculated on the basis of fiber-optic sensor data. A comparative analysis was carried out for the PCM represented as a homogeneous medium and as a laminated material for different directions of the prepreg reinforcements relative to the fiber and for different geometrical parameters of the resin pocket in the vicinity of the fiber....
The paper presents the results of a numerical analysis of the stresses in a polymer composite material (PCM) in the vicinity of an optical fiber embedded in the material, and the results from estimating the reliability of the strain values calculated on the basis of fiber-optic sensor data. A comparative analysis was carried out for the PCM represented as a homogeneous medium and as a laminated material for different directions of the prepreg reinforcements relative to the fiber and for different geometrical parameters of the resin pocket in the vicinity of the fiber....
30 décembre 2019
Study of ageing of laminates and its effects on wind turbine blade deflection - Nuin - - Wind Energy - Wiley Online Library
Study of ageing of laminates and its effects on wind turbine blade deflection - Nuin - - Wind Energy - Wiley Online Library
Some wind turbines have exceeded their nominal design service life and are continuing their operation with periodic inspections and maintenance. In the case of rotor blades, the reliability of the inspection is very limited because of the blade structure that comprises laminates and sandwich structures, which are very difficult to monitor. For this reason, wind farm owners are searching for technologies or approaches that will guarantee a safe operation of their wind turbines after the design life has elapsed.
Some wind turbines have exceeded their nominal design service life and are continuing their operation with periodic inspections and maintenance. In the case of rotor blades, the reliability of the inspection is very limited because of the blade structure that comprises laminates and sandwich structures, which are very difficult to monitor. For this reason, wind farm owners are searching for technologies or approaches that will guarantee a safe operation of their wind turbines after the design life has elapsed.
20 décembre 2019
Optimized Carbon Fiber Composites in Wind Turbine Blade Design | Department of Energy
Optimized Carbon Fiber Composites in Wind Turbine Blade Design | Department of Energy
DOE’s Sandia National Laboratories, Oak Ridge National Laboratory, and Montana State University completed a two-year WETO-funded study that demonstrates the commercial viability of cost-competitive carbon fiber composites selected for use in wind turbine blades.
Optimized Carbon Fiber Composites in Wind Turbine Blade Design
DOE’s Sandia National Laboratories, Oak Ridge National Laboratory, and Montana State University completed a two-year WETO-funded study that demonstrates the commercial viability of cost-competitive carbon fiber composites selected for use in wind turbine blades.
Optimized Carbon Fiber Composites in Wind Turbine Blade Design
12 décembre 2019
Sensitivity analysis of a parabolic equation model to ground impedance and surface roughness for wind turbine noise: The Journal of the Acoustical Society of America: Vol 146, No 5
Sensitivity analysis of a parabolic equation model to ground impedance and surface roughness for wind turbine noise: The Journal of the Acoustical Society of America: Vol 146, No 5
Input parameters of outdoor sound prediction models are related to environmental phenomena, such as atmospheric conditions and ground properties, which are variable in both time and space. In order to obtain reliable predictions, it is essential to get information on uncertainties by quantifying the sensitivity of numerical or analytical models to their input parameters, and thus determine the inputs that will be the main source of uncertainties. This paper focuses on ground parameters impact on sound propagation considering wind turbine noise. First, the implementation of ground roughness in a parabolic equation model validated against scale model measurements and analytical solution is proposed. Then, the sensitivity of the model to its ground parameters is performed with the Morris' screening method in order to access their relative influences. Three parameters are considered: the ground absorption through the airflow resistivity, the ground roughness through the roughness height, and correlation length. Results clearly show that the variations of ground roughness induce non-negligible differences in sound pressure levels regarding the ground absorption, even for high height sound source, i.e., nongrazing incidence.
Input parameters of outdoor sound prediction models are related to environmental phenomena, such as atmospheric conditions and ground properties, which are variable in both time and space. In order to obtain reliable predictions, it is essential to get information on uncertainties by quantifying the sensitivity of numerical or analytical models to their input parameters, and thus determine the inputs that will be the main source of uncertainties. This paper focuses on ground parameters impact on sound propagation considering wind turbine noise. First, the implementation of ground roughness in a parabolic equation model validated against scale model measurements and analytical solution is proposed. Then, the sensitivity of the model to its ground parameters is performed with the Morris' screening method in order to access their relative influences. Three parameters are considered: the ground absorption through the airflow resistivity, the ground roughness through the roughness height, and correlation length. Results clearly show that the variations of ground roughness induce non-negligible differences in sound pressure levels regarding the ground absorption, even for high height sound source, i.e., nongrazing incidence.
1 décembre 2019
Experimental investigation of a method to avoid channel marks during vacuum infusion - Arne Hindersmann,
Experimental investigation of a method to avoid channel marks during vacuum infusion - Arne Hindersmann
Today the impregnation of dry fibre materials is a production method preferred for large composite parts like wind turbine rotor blades or aircraft wing covers. One of the recurring problems of the production process is that the used resin distribution channels leave marks on the surface of the part. The result of the marks in the channel area is a localized deformation of the fibre material, and hence the laminate becomes more prone to shear buckling in this area. The purpose of this paper is to present a report on an unconventional infusion method to avoid channel marks on composite part's surfaces. The channels can be activated by a pressure difference. If the channels are deactivated during a specific process window no channel marks will be left on the part's surface. In order to verify the inexistence of channel marks, three analytical processes are used.
Today the impregnation of dry fibre materials is a production method preferred for large composite parts like wind turbine rotor blades or aircraft wing covers. One of the recurring problems of the production process is that the used resin distribution channels leave marks on the surface of the part. The result of the marks in the channel area is a localized deformation of the fibre material, and hence the laminate becomes more prone to shear buckling in this area. The purpose of this paper is to present a report on an unconventional infusion method to avoid channel marks on composite part's surfaces. The channels can be activated by a pressure difference. If the channels are deactivated during a specific process window no channel marks will be left on the part's surface. In order to verify the inexistence of channel marks, three analytical processes are used.
29 novembre 2019
Fabrication of continuous carbon fiber mesh for lightning protection of large-scale wind-turbine blade by electron beam cured printing - ScienceDirect
Fabrication of continuous carbon fiber mesh for lightning protection of large-scale wind-turbine blade by electron beam cured printing - ScienceDirect
Wind-turbine blades are more vulnerable to lightning strikes as they lack a protection system for large-scale glass fiber reinforced polymer (GFRP) composite structures. A low-energy electron beam (EB) cured printing process for fabricating a continuous carbon fiber-reinforced thermoset resin as a non-metallic lightning protection mesh on a GFRP composite surface was carried out in this study. During the proposed process, a continuous carbon fiber mesh was printed through a Fused Filament Fabrication that integrates the rapid curing of an epoxy resin with low-energy EB irradiation...
Wind-turbine blades are more vulnerable to lightning strikes as they lack a protection system for large-scale glass fiber reinforced polymer (GFRP) composite structures. A low-energy electron beam (EB) cured printing process for fabricating a continuous carbon fiber-reinforced thermoset resin as a non-metallic lightning protection mesh on a GFRP composite surface was carried out in this study. During the proposed process, a continuous carbon fiber mesh was printed through a Fused Filament Fabrication that integrates the rapid curing of an epoxy resin with low-energy EB irradiation...
27 novembre 2019
Déchets radioactifs : le débat public fait ressortir les questions d'éthique et de gouvernance
Déchets radioactifs : le débat public fait ressortir les questions d'éthique et de gouvernance
La Commission nationale du débat public a dévoilé, lundi 25 novembre, le compte-rendu du débat sur le 5e Plan national de gestion des déchets radioactifs. Il révèle une soif d'information du public sur l'éthique et la gouvernance du nucléaire.
La Commission nationale du débat public a dévoilé, lundi 25 novembre, le compte-rendu du débat sur le 5e Plan national de gestion des déchets radioactifs. Il révèle une soif d'information du public sur l'éthique et la gouvernance du nucléaire.
Comment Rennes est devenu un haut-lieu de la cybersécurité en France
Comment Rennes est devenu un haut-lieu de la cybersécurité en France
Avec 3 400 emplois directs, 70 entreprises privées et le siège du commandement militaire de la cyberdéfense (Comcyber), la métropole rennaise est devenue un haut-lieu de la cybersécurité en France, une situation héritée du gaullisme, dans un secteur en plein développement. A la fin des années 1960, le pouvoir souhaite implanter le Centre d’électronique de l’armement (Celar) en province. « Deux villes étaient en balance, Rennes/Bruz et Grenoble, Rennes l’emportant semble-t-il à la dernière minute», dans une région où avait été implanté le Centre national d’études des télécommunications (Cnet) à Lannion, explique Pierre-Arnaud Borrelly, délégué-général du Pôle d’excellence cyber (PEC).
Avec 3 400 emplois directs, 70 entreprises privées et le siège du commandement militaire de la cyberdéfense (Comcyber), la métropole rennaise est devenue un haut-lieu de la cybersécurité en France, une situation héritée du gaullisme, dans un secteur en plein développement. A la fin des années 1960, le pouvoir souhaite implanter le Centre d’électronique de l’armement (Celar) en province. « Deux villes étaient en balance, Rennes/Bruz et Grenoble, Rennes l’emportant semble-t-il à la dernière minute», dans une région où avait été implanté le Centre national d’études des télécommunications (Cnet) à Lannion, explique Pierre-Arnaud Borrelly, délégué-général du Pôle d’excellence cyber (PEC).
In-flight and wireless damage detection in a UAV composite wing using fiber optic sensors and strain field pattern recognition - ScienceDirect
In-flight and wireless damage detection in a UAV composite wing using fiber optic sensors and strain field pattern recognition - ScienceDirect
Aiming to provide more efficient, lightweight structures, composite materials are being extensively used in aerospace vehicles. As the failure mechanisms of these materials are complex, damage detection becomes challenging, requiring advanced techniques for assessing structural integrity and maintaining aircraft safety. In this context, Structural Health Monitoring (SHM) seeks for integrating sensors into the structures in a way that Nondestructive Testing (NDT) is implemented continuously. One promising approach is to use Fiber Optic Sensors (FOS) to acquire strain signals, taking advantages of their capabilities over conventional sensors.....
Aiming to provide more efficient, lightweight structures, composite materials are being extensively used in aerospace vehicles. As the failure mechanisms of these materials are complex, damage detection becomes challenging, requiring advanced techniques for assessing structural integrity and maintaining aircraft safety. In this context, Structural Health Monitoring (SHM) seeks for integrating sensors into the structures in a way that Nondestructive Testing (NDT) is implemented continuously. One promising approach is to use Fiber Optic Sensors (FOS) to acquire strain signals, taking advantages of their capabilities over conventional sensors.....
22 novembre 2019
CONNECTION JOINT FOR A SECTIONAL WIND TURBINE ROTOR BLADE AND ASSOCIATED METHODS - Vestas Wind Systems A/S
CONNECTION JOINT FOR A SECTIONAL WIND TURBINE ROTOR BLADE AND ASSOCIATED METHODS - Vestas Wind Systems A/S
A wind turbine blade includes a first blade section and a second blade section configured to be coupled together at a joint interface. The blade further includes a connection joint for coupling the first and second blade sections together. The connection joint includes a plurality of connecting elements integrated into the first and second blade sections at the first and second blade interfaces. The connection joint further includes cross pins and fasteners for making the connection. A method of making a wind turbine blade section and a wind turbine blade made from such sections are also disclosed.
A wind turbine blade includes a first blade section and a second blade section configured to be coupled together at a joint interface. The blade further includes a connection joint for coupling the first and second blade sections together. The connection joint includes a plurality of connecting elements integrated into the first and second blade sections at the first and second blade interfaces. The connection joint further includes cross pins and fasteners for making the connection. A method of making a wind turbine blade section and a wind turbine blade made from such sections are also disclosed.
Inscription à :
Articles (Atom)