Éditeur(s) : HAL CCSD Intech
Résumé : International audience
The massive integration of sustainable energies into electrical grids (non-interconnectedor connected) is a major problem due to their stochastic character revealed by strongfluctuations at all scales. In this paper, the scaling behaviour or power law correlationsand the nature of scaling behaviour of sustainable resource data such as flow velocity,atmospheric wind speed, solar global solar radiation and sustainable energy such as,wind power output, are highlighted. For the first time, Fourier power spectral densitiesare estimated for each dataset. We show that the power spectrum densities obtained areclose to the 5/3 Kolmogorov spectrum. Furthermore, the multifractal and intermittentproperties of sustainable resource and energy data have been revealed by the concavityof the scaling exponent function. The proposed analysis frame allows a full descriptionof fluctuations of processes considered. A good knowledge of the dynamic of fluctua-tions is crucial to management of the integration of sustainable energies into a grid.
Sustainable Energy - Technological Issues, Applications and Case Studies

hal-01528087
https://hal.archives-ouvertes.fr/hal-01528087
DOI : 10.5772/106341

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The correlation between the flow turbulence and the performances of a ma- rine current turbine is studied. First, the incoming flow encountered in the flume tank is characterized in the framework of fully developed turbulent cascades in the inertial range. The Reynolds number, the Kolmogorov dissipation scale and the integral scale, are estimated from flow measurements. The intermittency of the turbulence is characterized in the lognormal multifractal framework, and the influence of the turbulent flow on the turbine power is assessed. The rotor speed control unit characteristics used for the turbine regulation induces non-negligible effects on the turbine behavior under fluctuations loads. Even if the power spectrum does not reveal any scale invariance, a multiscale analysis allows us to show the correlations between the turbulence time se- ries and the power produced. The classical Mean Square Coherency function shows that for scales larger than 10 seconds, the upstream velocity and power have large correlations. In the framework of the Empirical Mode Decomposition method, such correlations are studied using the time-dependence intrinsic corre- lation analysis method. This method allows to zoom into time-frequency scales where the flow perturbations induced some modifications in power production
ISSN: 0960-1481

hal-01528296
https://hal.archives-ouvertes.fr/hal-01528296
DOI : 10.1016/j.renene.2017.05.024

Éditeur(s) : HAL CCSD
Résumé : International audience
There is growing efforts for the development of wind energy. Yet, as for other renewable resources, a basic characteristic of wind energy is to deliver intermittent power. In this paper, we consider this topic by analyzing data provided by the wind industry. We discuss first the spectral properties of the data and the corresponding power curve. We estimate the scaling behavior in the inertial scale of wind input and the power output. We also study the rotor revolution scaling fluctuations. Finally the wind/power transfer function is studied, together with the wind/rotation and rotation/power intermediary transfer functions.
Energy Procedia

hal-01273262
https://hal.archives-ouvertes.fr/hal-01273262
DOI : 10.1016/j.egypro.2015.07.897

Éditeur(s) : Séminaire CLAROM, 14èmes journées de l'Hydrodynamique, Val de Reuil, 18-20 novembre 2014
Résumé : From measurements obtained at high level frequency over a long period of time, we aim to determine the different characteristics of the flow situated in the IFREMER (French Research Institute for Exploration of the Sea) wave and current flume tank in Boulogne-Sur-Mer. This 2 data measured with a LDV (Laser Doppler Velocimetry) allows to get the characteristics of turbulence and the incident velocity fluctuations. The well-controlled conditions in the flume and the high sampling frequency of LDV system will give us a good estimate of the different flow characteristics such as dissipation, the Reynolds number, the injection scales, Taylor and Kolmogorov. The objective is to place the marine current turbine in this flow and then to study the influence of turbulence on the rotor of this turbine. The flow velocity is imposed and two different rates of turbulence are analysed.
A partir de données à haute fréquence acquises pendant une longue période de temps, on cherche à déterminer les différentes caractéristiques de l’écoulement généré au bassin d’essais à houle et courant d’IFREMER à Boulogne-Sur-Mer. Ces données mesurées avec un système LDV permettent de caractériser la turbulence et les fluctuations de la vitesse du courant incident. Les conditions contrôlées du bassin et les longues périodes d’acquisition du système LDV nous donneront une bonne estimation des différentes caractéristiques de l’écoulement tels que la dissipation, le nombre de Reynolds, les échelles d’injection, de Taylor et de Kolmogorov. Dans un deuxième temps nous étudions les effets de la turbulence de l’écoulement sur le comportement d’une hydrolienne tri-pale à axe horizontal.L’objectif est de placer la maquette d’hydrolienne dans cet écoulement et étudier l’influence de la turbulence sur le rotor de cette turbine. La vitesse de l’écoulement est imposée et deux taux de turbulence différents ont été étudiés.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00247/35814/34329.pdf
http://archimer.ifremer.fr/doc/00247/35814/