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This paper presents a lifting‐line implementation in the framework of a Lagrangian vortex particle method (LL‐VP). The novelty of the present implementation lies in the fluid particles properties definition and in the particles shedding process. In spite of mimicking a panel method, the LL‐VP needs some peculiar treatments described in the paper. The present implementation converges rapidly and efficiently during the shedding sub‐iteration process. This LL‐VP method shows good accuracy, even with moderate numbers of sections. Compared to its panel or vortex filaments counterparts, more frequently encountered in the literature, the present implementation inherently accounts for the diffusion term of the Navier‐Stokes equations, possibly with a turbulent viscosity model. Additionally, the present implementation can also account for more complex onset flows: upstream ambient turbulence and upstream turbine wakes. After validation on an analytical elliptic wing configuration, the model is tested on the Mexnext‐III wind turbine application, for three reduced velocities. Accurate results are obtained both on the analytical elliptic wing and on the New MEXICO rotor cases in comparison with other similar numerical models. A focus is made on the Mexnext‐III wake analysis. The numerical wake obtained with the present LL‐VP is close to other numerical and experimental results. Finally, a last configuration with three tidal turbines in interaction is considered based on an experimental campaign carried out at the IFREMER wave and current flume tank. Enhanced turbine‐wake interactions are highlighted, with favourable comparisons with the experiment. Hence, such turbine interactions in a farm are accessible with this LL‐VP implementation, be it wind or tidal energy field.

This experimental study investigates blade root load fluctuations for a single turbine immersed in a regular current flow with different ambient turbulence conditions. Two scaled models of industrial prototypes were tested: a 1:28 scale model of the three-bladed horizontal axis turbine of Magallanes Renovables and a 1:20 scale model of the five-bladed horizontal axis turbine of Sabella. The rotor loads were directly measured on the rotation axis with a thrust and torque sensor. The blade roots were equipped with a load-cell measuring two forces and three moments. The variations of the rotor loads (thrust and torque) and the blade root loads (edgewise bending moments and streamwise forces) are compared and the impact of the blade angular position is investigated. A comparison of both scaled models results with those of the IFREMER generic turbine is also presented. The results are anonymised in order to ensure confidentiality.

Until now, no pan-European nor worldwide consensus on appropriate test methodologies and practices have yet been implemented in order to carry out standard laboratory tests. For performance test (in laboratory as well as in-situ), the measurement of the upstream flow velocity is required to calculate kinetic energy, especially when the turbulence intensity is high. These flow fluctuations affect significantly the performance and fatigue behaviour of tidal turbines. However, for a good accuracy the upstream flow measurement needs to be performed in a synchronous way with the turbine parameters. In this paper, we study the time and space correlation between velocity measurements and turbine parameters in order to evaluate and improve the specifications given in IEC TS 62600–200 to 202 for the current profiler placement relative to the turbine.

Experimental results of tests carried out to investigate the hydrodynamics of marine current turbines are presented The objective is to build an experimental database in order to validate the numerical developments conducted to characterise the flow perturbations induced by marine current turbines For that purpose, we used a tri-bladed horizontal axis turbine The work is dedicated to measuring the behaviour of the system and to characterising the wake generated by the turbine The efficiency of the device is quantified by the measurement of the thrust and the amount of power generated by the rotor for various inflow conditions, whereas the wake is characterised by Laser Doppler Velocimetry Particular attention is paid to the flow characteristic effects on the performance of a 0 70 m diameter turbine The load predictions on the structure and the measured performance of the turbine over its working range of currents and rotational speeds are presented The results showed that this kind of turbine is sensitive to the quality of the incoming flow The turbulence intensity effects on turbine behaviour and on its wake are also characterised in order to study how the far wake decays downstream and to estimate the effect produced in downstream turbines