Abstract

Abstract

Nowadays the marine renewable energies are getting an important role in the transformation of the energy model. And tools for predicting the performance of these new technologies are essential in their commercial development. An example of these are floating wind turbines (FWT), and this work presents the coupling and verification of a set of tools to carry out fully coupled simulation of FWTs. These tools are built on the seakeeping software SeaFEM [1, 2, 3, 4, 5] and on the aeroelastic simulator code FAST [6].

First, the basic features of each tools are explained. Second, a coupling strategy to assess the performance of FWTs is presented. Third, the results obtained coupling SeaFEM-FAST are used for an inter-code comparison against those obtained coupling Hydrodyn-FAST. Forth, an intensive analysis of a FWT based on the NREL 5 MW baseline is carried out taking into account the environmental conditions of the selected location. These coupled computations are carried out following the Design Load Cases proposed by IEC rules [7] to assess the Ultimate Limit State (ULS). Finally, some comparison and conclusions based on the obtained results are drawn.

Abstract

feasibility study for the installation of Wave Energy Converters (WEC) in a Spanish Mediterranean port is evaluated in this paper. The final aim is to evaluate the possibility of building a new infrastructure which combines a breakwater and a WEC able to provide energy to the commercial port of Valencia. An estimation of the wave power potential is made according to existing databases from different sources. A review of the existing WEC types is carried out in order to choose the most suitable technology for its installation in a port environment. The authors discuss the main advantages and issues of the integration of WEC in port breakwaters. A prospective study for the Port of Valencia is made, considering the port energy demand evolution, historical data on wave energy potential and the port expansion plans. We conclude that Overtopping Devices (OTDs) are the most suitable ones to allow the good integration with the new breakwater needed for the expansion of the Port of Valencia and we give an estimation on the power available from the resource in our case study.

Abstract

Abstract

In the context of future offshore wind farms along the French coasts of the English Channel, the impacts of foundations on larval dispersal from bentho-pelagic species colonizing the hard substratum of artificial structures are studied in order to assess how the species connectivity could be modified by the farms. In particular, the effects of turbulent wake and horseshoe vortices are investigated. To this end, a new numerical approach is developed that combines the Eulerian model, OpenFoam, solving the 3D Navier-Stokes equations to compute the hydrodynamics, and the Lagrangian model, Ichthyop, based on an advection-diffusion equation to compute the larval trajectories. Firstly, some simple test cases are performed to validate the numerical coupling between OpenFoam and Ichthyop, such as the dispersion of larvae downstream a 2D cylinder in water. Secondly, the ability of OpenFoam turbulence models to simulate turbulent structures around monopile and gravity type foundations is evaluated. The RANS (Reynolds Averaged Navier-Stokes) k-omega SST turbulence model is chosen for the realistic application because it can reproduce the horseshoe vortices and turbulent wake with less computing time than the Smagorinsky LES (Large Eddy Simulation) model. Lastly, larval dispersal simulations for four benthic species and for a set of monopile and gravity foundations are performed.