Model-free anti-swing control of complex-shaped payload with offshore floating cranes and a large number of lift wires

Being one of the most commonly used offshore operations, offshore lifting operations become increasingly challenging due to the gradually growing size and weight of payloads. The research on automatic control in lifting operations, e.g., anti-swing control and heave compensation, only considers simple-shaped payloads, such as lumped-mass...

Modelling the dynamic behaviour of a rotor nacelle assembly during the installation using a floating vessel

The offshore wind energy industry has been developing rapidly due to the increasing demand for renewable energy. As a result, offshore wind turbines are increasing in mass and height and are installed at larger water depths and further away from shore. A floating vessel is not limited by water depth and soil conditions, but is sensitive to wave...

A hydrodynamic analysis of three floating offshore wind-wave energy converters differing in the floating stability principle

A significant percentage of the offshore wind resource is located in waters deeper than 60m. Therefore, several floating offshore wind turbines (FOWT) have been conceived in recent years. In deep waters, it seems logical to also harvest wave energy. One of the options to harness both resources is to use a floating offshore hybrid wind-wave...

Preliminary Propulsion System Design and Integration for a Box-Wing Aircraft Configuration: A Knowledge Based Engineering Approach

The design and integration of the propulsion system is known to be an interesting, multi-disciplinary challenge in aircraft design projects. Especially for new aircraft configurations, it is important to gain a lot of knowledge in the preliminary design stages. An example of such an unconventional configuration is the box-wing aircraft examined...

Multi-disciplinary Optimization of Rotor Nacelle Assemblies for Offshore Wind Farms: An Agile Systems Engineering Approach

The models with different fidelities for the siloed application of niche wind farm disciplines - rotor aerodynamics, aeroelasticity or wake aerodynamics - are prevalent in literature. These models are often used sequentially while designing a wind farm that may lead to a sub-optimal design due to their agnosticism towards the inter-disciplinary...

Wind Turbines near Flood Defences: Study on the impact craters of falling nacelles hitting a dike

Building wind turbines near flood defences has numerous advantages over other locations on land. The water authorities, which own the land of the flood defence, will only permit the turbines if the flood protection assessment satisfies the safety standard after the wind turbines have been constructed. There are three types of failure of a wind...

Field-test of nacelle-based lidar to explore its applications for Vattenfall as wind park operator

The market share of wind energy is related to many factors, including politics, social acceptance and financial feasibility. In light of reducing the Levelised Energy Cost (LEC) generated from wind energy, power company Vattenfall is continuously looking for new ways of monitoring and improving wind turbine yield. Recent publications have shown...

Design study of a 10 MW MgB2 superconductor direct drive wind turbine generator

A superconducting direct drive generator based on field windings of MgB2 superconducting tape is proposed as a solution by mounting the generator in front of the blades using a king-pin nacelle design for offshore turbines with power ratings larger than 10 MW as investigated in the INNWIND.EU project.

A Comparative Analysis of the Two-Bladed and the Three-Bladed Wind Turbine for Offshore Wind Farms

Background: As the installation of offshore wind farms continues to increase, the need to optimize on costs involved is a constant factor in the industry. In this regard, research into the two-bladed rotor has garnered some interest in the recent past, to see if the optimum cost can be shifted in the favor of the two-bladed wind turbine....

The engine/airframe interference drag at cruise conditions using propulsion simulation

A wind tunnel test procedure is described to determine from the thrust minus drag measurements the aircraft drag and engine/airframe interference drag at cruise conditions. The definitions of the thrust and drag terms in use are given. Engine thrust simulation is provided by a calibrated Turbofan Powered Simulator (TPS). Further the use of a...

Evaluation of Thing's method for the calculation of the lift discription on a wing in propulsive jets

The calculation method presented by Ting, Liu and Kleinstein in reference 3 has been subjected to an evaluation study, principally on the basis of experimental data obtained from special experiments on a half wing immersed in two jets. Very satisfactory results were found for the unflapped wing lying centrally within the jets. Both flap...

Wind-tunnel measurements on the interference between a jet and a wing, located outside the jet. Part I: text, tables and figures

This report describes a wind-tunnel investigation on the interference between a jet and a wing half model, located outside the jet. Pressure distributions on the wing, and lift coefficients calculated from those have been used for evaluation of a method developed at NLR for the prediction of interference effects between jets and parts of...

Evaluation of a method for the prediction of jet-airframe interference

A brief description is given of a method, developed at NLR for the prediction of interference effects between (propulsion) jets and parts of airframes. The jet flow region is described by a model for a jet in a nonuniform mainflow, accounting for the presence of the airframe. The potential flow field around the airframe-jet combination is...

The effect of a pylon-mounted nacelle on the flutter behaviour of a wing-pylon-nacelle configuration