Validation and analysis of loading models for a multi-megawatt floating offshore two-bladed wind turbine

Offshore wind is a rapidly maturing renewable energy technology and is expected to play a central role in future energy systems. It has the potential to generate more than 420,000 TWh per year worldwide, an amount approximately equal to eighteen times the global electricity demand today. While many of the most abundantly resourceful sites are at...

CFD Simulation of a Floating Wind Turbine with OpenFOAM: an FSI approach based on the actuator line and relaxation zone methods

Floating offshore wind turbines (FOWTs) have the potential to harness wind resources in deepwater, which is so far prohibitive for conventional approaches. This, however, comes at a cost: the platform’s extra degrees of freedom (DoFs) introduce complex aerodynamic and hydrodynamic behaviours. Therefore, FOWTs must be accurately modeled to reduce...

Quasi-dynamic modelling of shared mooring lines for floating wind turbines

The idea of shared mooring systems has been introduced in the offshore wind farm industry as an effort to lower the overall installation costs for floating offshore wind farms. The reason for building such plants is that using floating turbines allows them to move to deeper waters, reducing visual and environmental impact and allowing footprint...

Techno-economic analysis of the installation and O&M of far-offshore floating wind turbines

Renewable forms of energy, and especially wind energy, have become an integral part of the energy infrastructure around the globe. However, the constant increase of installed wind capacity has put a strain on the selection of potential onshore locations for wind turbine installation. As a result, the wind industry is focusing on offshore...

Aerodynamics of a 15-MW and a 5-MW Reference Wind Turbine Using Varying Fidelity Tools

The most effective way to decrease the cost of energy of wind turbines is to increase the rotor diameter. Therefore, this calls for the need of aerodynamic research on large wind turbines. This thesis project will tackle the topics addressed by the IEA Wind Task 47 which is focused on the aerodynamic analysis and comparison of the newly proposed...

Low-Frequency Hydrodynamic Modeling of a 12 MW Semi-Submersible Wind Turbine

Steady-state RANS simulation of a leading edge inflatable wing with chordwise struts

A crosswind pumping kite power system is an Airborne Wind Energy (AWE) system that uses a flying tethered device for energy generation through a ground-based generator. The AWE research group of the TU Delft was one of the first to demonstrate the functioning of such a system. The spin-off Kitepower later on continued the technological...

Comparison of Potential Flow and CFD for a Column With Heave Plate

Floating offshore wind turbines can only withstand a limited amount of (heave) motions before the equipment fails. In order to reduce the heave motion, the DeepCwind floater for offshore floating wind turbines makes use of heave plates. This semi-submersible floater consists of three cylindrical columns with a heave plate attached to the bottom...

Enhancement of data-driven turbulence models for wind turbine wake applications

Wind turbine wakes cause significant reductions in power production and increased fatigue damage for downwind turbines. Thus, they affect the wind levelized cost of energy. Computational Fluid Dynamics (CFD) can be used to quantify the wake characteristics, whereby Reynolds-averaged Navier-Stokes (RANS) has the most potential for industrial...

Robust energy production optimization of a wind farm using wake steering by calibrating the FLORIS model on SCADA data

Wind farms experience significant efficiency losses due to the aerodynamic interaction between turbines. A possible control technique to reduce these losses to a minimum is yaw-based wake steering. This thesis investigates the feasibility of this technique by calibrating a surrogate model called the FLOw Redirection and Induction in Steady-state...

Machine learning and image analysis on photos of a solitary tree in a complex background: extraction and analysis of key properties for wind-tree interaction

A method is developed to automatically analyze over 200000 images of a single mature tree. This method is assessed and applied to a tree located at Risø in Roskilde, Denmark, next to two meteorological masts. Image aspects such as the surface area and the center of area are extracted from the images and they are related to the wind statistics....

A fluid-multibody coupling for aeroelastic applications to rotorcraft and wind turbines

Accurate aerodynamic and aeroacoustic simulations of helicopters and wind turbines require the inclusion of the blade elasticity into the computational setup. If low-order aerodynamic models can be efficient for optimization purposes, they are often insufficient in predicting the complex flow phenomena responsible for structural vibrations and...

Wave-structure interaction study, in the context of floating wind turbines, by mean of coupled rigid body code and Fluidity CFD software

Offshore wind energy is a fast-growing sector in the energy industry, and the cost of electricity per kilowatt-hour from offshore wind is decreasing significantly. Until now, offshore wind turbines are mainly installed on bottom-mounted foundations, which are economically feasible in shallow waters. This factor has limited the development of...

Design of a 10MW Wind Turbine Rotor Blade for Testing of a Scaled-down Floating Offshore Support Structure

Floating offshore wind energy is being widely implemented in deep-water sites thanks to its numerous advantages, which among others include the access to stronger and undisturbed wind resources. In addition, considering the fast-paced growth in size and power generating capacity of offshore wind turbines, the designs of floating foundations need...

Computation of Nonlinear Wave Loads on Floating Structures

Floating wind turbines (FWTs) are proposed as a method to harness the significant wind energy resource in deep water. International research efforts have led to the development of coupled numerical global analysis tools for FWTs in order to understand their behavior under wind and wave actions. The hydrodynamic models in such tools are typically...

Methodology Improvement for Performance Assessment of Pumping Kite Power Wing

Pumping kite power systems are a promising way of harnessing clean energy from high-altitude winds. A large kite flies crosswind developing a strong pulling force through a tether which is connected at the ground to an electrical generator. The power output of such innovative systems is directly related to the wing aerodynamic properties which...