R & D

Research at TUDelft



Introduction
        This page gives a quick review of the research that takes place on wind energy in the TUDelft.


Smart rotors
        Advanced control concepts for load reduction on large wind turbine rotor blades are investigated. Research focuses on the design of smart rotor blades, i.e. blades with integrated aerodynamic control devices that can be controlled actively and independently. With the combination of advanced materials, actuators, sensors and controllers this smart control concept will operate in a way that fulfils the required strategy (e.g. alleviation of fast fluctuating fatigue loads).
        Main research objectives:
-Prove the feasibility of significant blade load alleviation by applying spanwise-distributed smart load control devices through aeroservoelastic models and scaled wind tunnel experiments.
-Provide design guidelines for smart wind rotor wind turbines.
        In the video below, the result of the smart control on an oscillating blade is shown.

     


Built environment and Vertical Axis Wind Turbines
        The increasing awareness of the need for environmentally sustainable housing and cities has driven the development of wind energy conversion systems for the built environment. One of the results of the development of solutions for the built environment is the reappearance of Vertical Axis Wind Turbines (VAWTs). Extensive research on VAWTs was conducted until the end of the 1980s (especially in North America), when, due to the increasing success of the application of Horizontal Axis Wind Turbines (HAWTs) in Europe, it was discontinued.
        Yet, in the built environment, VAWTs present several advantages over the more common HAWTs, namely: low sound emission (a consequence of its operation at lower tip speed ratios), better esthetics due to its three-dimensionality (more suitable for integration in some architectural projects, since it follows the concept of volume of the building), its insensitivity to yaw and its increased performance in skew. The current research aims at understanding the physical drivers of VAWT aerodynamics and implications on design of operation in urban environments.
        In the first video below, Turby is shown at test field, a VAWT developed at TUDelft. In the second video, the results from a model for the wakes from a two bladed VAWT is shown.

                      


Wind turbines upscaling
        The objective of this research is to investigate the future of offshore wind turbines, with final aim for bigger machines. It contains aeroelastic design optimization of the current concepts for larger scales. The entire wind turbine is modeled using an aeroelastic solver to do the simulation of different sizes and turbine configurations. The model is linked with an optimizer to optimize the entire system. Cost of energy is the objective function and design variables are all structural parameters like thickness and stiffness. Level of stresses, displacements, buckling, modal frequencies and fatigue are design constraints.


Intelligent Maintenance approach for offshore wind turbines
        The objective of this on-going research is to develop a design methodology to increase reliability and availability for offshore wind farms, by means of an intelligent maintenance system capable of responding to faults by reconfiguring the system or subsystems, without increasing service visits. Within the wind farm, there are different levels at which this reconfiguration concept can be applied. The possible solutions can range from using information from adjacent wind turbines to setting up different operational modes.


Use of site data for offshore wind turbine design
        At offshore sites lot of data has been gathered on wind and wave conditions. However, very little has been gathered from the wind energy point of view. Moreover, the design of offshore wind turbines has been based so far mainly on onshore wind turbines. However, recent research has proved that it is not ingenious to use the same input conditions as that for onshore turbines. For e.g. the use of logarithmic wind profile is not recommended without considering atmospheric stability. The turbulence spectrum at offshore sites is yet to be verified with measurements to be able to use for dynamic calculations. All this requires huge amount of data to obtain the design input conditions.
         The objective of this research is to obtain the design input conditions from the available data and carry out dynamic calculations using an aeroelastic simulation code. In the end, verification of the results with the load measurements would be done to ratify the analysis. The results from such analysis would at first provide an argument for the use of site data to obtain the design input conditions and furthermore provide a methodology to make use of the available site data.


Scenarios of the development of offshore wind energy in the Netherlands Development paths towards 6000 MW by 2030
        In the Netherlands, offshore wind energy shows promise for large-scale implementation due to the abundance of this source of energy and an opportunity arises for Dutch enterprise. We want to see how offshore wind energy could fit in the energy transition while taking into account the three issues: first, the perspectives of different actors on the acceptability of the implementation and how their actions could influence this implementation; second, the timing and availability of resources, accounting for time to change; third, the changing surroundings of the actors and the uncertainty of the future. The aim of the research is to find the barriers to the development of large-scale offshore wind energy in the Netherlands, taking into account the uncertainties of the future and the consequences of decisions, from economical, technical, social, political and environmental perspectives, towards a target of 6000 MW, to aid and prepare the stakeholders. The approach is to develop possible and realistic scenarios for the implementation of 6000 MW of offshore wind energy in the Dutch EEZ using an Agent-Based Model.


Mexico experiment
        The objective of this project is to reduce the uncertainties that exist in current design calculations for performance prediction and dynamic load prediction of wind turbines. The aim is to provide an experimental database, measured in a large wind tunnel under controlled and hence known conditions and by using the increased physical insight, resulting from the experiments in engineering design methods. At the same time, the database is necessary to provide a validation tool for the upcoming area of Navier Stokes based calculation techniques. The improvement of engineering design codes ia a short-term objective. It will be available shortly after the end of the project. The effect of Navier Stokes validation on the design practice can be expected to take place within a period of five to seven years.
        In the video below, some phases of the Mexico experiment are shown