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Matias, Ana (author), Carrasco, Ana Rita (author), Loureiro, Carlos (author), Andriolo, Umberto (author), Masselink, Gerd (author), Guerreiro, Martha (author), Pacheco, A (author), McCall, R.T. (author), Ferreira, Óscar (author), Plomaritis, Theocharis A. (author)Overwash hydrodynamics datasets are mixed in quality and scope, being hard to obtain due to fieldwork experimental difficulties. Aiming to overcome such limitations, this work presents accurate fieldwork data on overwash<br/>hydrodynamics, further exploring it to model overwash on a low-lying barrier island. Fieldwork was performed on Barreta...conference paper 2017
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Berdowski, T.J. (author), Ferreira, Carlos (author), van Zuijlen, A.H. (author), van Bussel, G.J.W. (author)A PhD project is being carried out on the topic of far-wake aerodynamics of Horizontal Axis Wind Turbines (HAWTs) in yawed conditions, which has a large relevance for wind farm design and optimization. Characteristic for a turbine in yaw are the inherent unsteady and non-uniform rotor loading, and the typical wake deflection and strong three...abstract 2017
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LeBlanc, B.P. (author), de la Garza Cuevas, R. (author), Ferreira, Carlos (author)Research into the Vertical Axis Wind Turbine (VAWT) has been progressing over the last few years due to<br/>the large shift in design constraints for large floating offshore wind turbines by leveraging tools and experience<br/>from research beginning in the 1970s and lasting until the HAWT established market dominance in the 1990s. The beginning...abstract 2017
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Prasanth, V. (author), Bandyopadhyay, S. (author), Bauer, P. (author), Ferreira, Jan Abraham (author)This paper deals with a generic methodology to evaluate the magnetic parameters of contactless power transfer systems. Neumann's integral has been used to create a matrix method that can model the magnetics of single coils (circle, square, rectangle). The principle of superposition has been utilized to extend the theory to multi-coil...journal article 2017
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Wang, X. (author), Liu, D. (author), Lahaye, D.J.P. (author), Polinder, H. (author), Ferreira, Jan Abraham (author)The brushless doubly-fed induction machine (DFIM) has great potential as a variable-speed generator for wind turbine applications. This special machine has a richer space-harmonic spectrum due to its special nested-loop rotor construction compared with conventional induction machines. It may result in higher iron losses, higher torque ripple and...conference paper 2017
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Ragni, D. (author), Ferreira, Carlos (author)A 3D stall-cell flow-field has been studied in a 4.8 aspect-ratio wing obtained by linear extrusion of a laminar NACA64-418 airfoil profile. The span-wise change in the velocity and pressure distribution along the wing has been quantified with respect to the development of cellular structures from 8◦ to 20◦ angle of attack. Oil-flow...journal article 2017
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Koppenol, Boy (author), Cheng, Zhengshun (author), Gao, Zhen (author), Ferreira, Carlos (author), Moan, T (author)This paper presents a comparison of two state-of-the-art codes that are capable of modelling floating vertical axis wind turbines (VAWTs) in fully coupled time-domain simulations, being the HAWC2 by DTU and the SIMO-RIFLEX-AC code by NTNU/MARINTEK. The comparative study focusses on the way aerodynamics, hydrodynamics and structural dynamics are...conference paper 2017
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Wang, X. (author), Liu, D. (author), Lahaye, D.J.P. (author), Polinder, H. (author), Ferreira, Jan Abraham (author)Permanent-magnet machines with fractional slot concentrated windings are easy to manufacture. Their popularity therefore is steadily increasing. Without a proper design, however, the induced eddy-current losses in the solid rotor get rather high. The modeling and the prediction of eddy-current losses for these machines are thus very important...conference paper 2016
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Micallef, D. (author), Sant, Tonio (author), Ferreira, Carlos (author)The performance of a wind turbine located above a cubic building is not well understood. This issue is of fundamental importance for the design of small scale wind turbines. One variable which is of particular importance in this respect is the turbine height above roof level. In this work, the power performance of a small wind turbine is...journal article 2016
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Ferreira, Carlos (author), Gonzalez, A. (author), Baldacchino, D. (author), Aparicio, M. (author), Gomez, S (author), Munduate, X. (author), Garcia, N. R. (author), Sørensen, J. N. (author), Jost, E. (author), Knecht, S. (author), Lutz, T. (author), Chassapogiannis, P. (author), Diakakis, K. (author), Papadakis, G. (author), Voutsinas, S. (author), Prospathopoulos, J. (author), Gillebaart, T. (author), van Zuijlen, A.H. (author)The FP7 AdVanced Aerodynamic Tools for lArge Rotors - Avatar project aims to develop and validate advanced aerodynamic models, to be used in integral design codes for the next generation of large scale wind turbines (10-20MW). One of the approaches towards reaching rotors for 10-20MW size is the application of flow control devices, such as...journal article 2016
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Ceyhan, J. G Schepers O (author), Ceyhan, O (author), Boorsma, K. (author), Gonzalez, A. (author), Munduate, X. (author), Pires, O. (author), Sørensen, N. (author), Ferreira, Carlos (author), Sieros, G. (author), Madsen, J. (author), Voutsinas, S. (author), Lutz, T. (author), Barakos, G. (author), Colonia, S. (author), Heißelmann, H. (author), Meng, F. (author), Croce, A. (author)This paper presents the most recent results from the EU project AVATAR in which aerodynamic models are improved and validated for wind turbines on a scale of 10 MW and more. Measurements on a DU 00-W-212 airfoil are presented which have been taken in the pressurized DNW-HDG wind tunnel up to a Reynolds number of 15 Million. These measurements...journal article 2016
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Sørensen, Niels N. (author), Méndez, B. (author), Muñoz, A. (author), Sieros, G. (author), Jost, E. (author), Lutz, T. (author), Papadakis, G. (author), Voutsinas, S. (author), Barakos, G. N. (author), Colonia, S. (author), Baldacchino, D. (author), Baptista, C.F. (author), Ferreira, Carlos (author)The current paper presents the effort, in the EU AVATAR project, to establish the necessary requirements to obtain consistent lift over drag ratios among seven CFD codes. The flow around a 2D airfoil case is studied, for both transitional and fully turbulent conditions at Reynolds numbers of 3 × 10<sup>6</sup> and 15 × 10<sup>6</sup>. The...journal article 2016
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Strous, T.D. (author), Shipurkar, U. (author), Polinder, H. (author), Ferreira, Jan Abraham (author)In this paper, the brushless DFIM based wind turbine drive-train topology is compared to the DFIG based and PM generator based drive-train topologies, that are most commonly applied in modern wind turbines. The comparison will be based on a 3:2MW case study wind turbine. By using FE based multi-objective optimization, optimized generator designs...journal article 2016
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Liu, D. (author), Polinder, H. (author), Abrahamsen, Asger Bech (author), Ferreira, Jan Abraham (author)Superconducting synchronous generators (SCSGs) are being proposed for 10-MW direct-drive wind turbines, because of their advantages of low weight and compactness. So far, however, there has not been a commonly accepted design philosophy of SCSGs and various possibilities with many tradeoffs remain for study. Partially SCSGs are considered a...conference paper 2016
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Sant, T. (author), Del Campo, V. (author), Micallef, D. (author), Ferreira, Carlos (author)Lifting line vortex models have been widely used to predict flow fields around wind turbine rotors. Such models are known to be deficient in modelling flow fields close to the blades due to the assumption that blade vorticity is concentrated on a line and consequently the influences of blade geometry are not well captured. The present study...journal article 2016
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Shipurkar, U. (author), Polinder, H. (author), Ferreira, Jan Abraham (author)Availability is an important factor to be considered when designing wind turbine generator systems. The quest for increasing availability is based on the following five design approaches - design for component reliability, active control for reliability, design for fault tolerance, prognostics, and design for maintainability. This paper reviews...journal article 2016
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Ferreira, J.P. (author), De Breuker, R. (author)This study describes the development of a morphing wing concept for a Portuguese Air Force Unmanned Air Vehicle (UAV), the UAS-30. Nowadays, optimized fuel efficiency is a primary requirement in the aerospace industry, and it can be significantly improved by designing adaptive wings which can change their shape in flight to achieve better...conference paper 2016
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Baldacchino, D. (author), M Manolesos, M. (author), Ferreira, Carlos (author), Gonzalez Salcedo, A (author), Aparicio, M. (author), Chaviaropoulos, T. (author), Diakakis, K. (author), Florentie, L. (author), Garcia, M. (author), Papadakis, G (author), Sorensen, N.N. (author), Timmer, W.A. (author), Troldborg, N. (author), Voutsinas, S. (author), van Zuijlen, A.H. (author)Experimental results and complimentary computations for airfoils with vortex generators are compared in this paper, as part of an e_ort within the AVATAR project to develop tools for wind turbine blade control devices. Measurements from two airfoils equipped with passive vortex generators, a 30% thick DU97W300 and an 18% thick NTUA T18 have been...journal article 2016
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Berdowski, T.J. (author), Walther, J. (author), Ferreira, Carlos (author), Meng, F. (author)In the current paper, a method for deriving the analytical expressions for the velocity and vortex stretching terms as a function of the spherical multipole expansion approximation of the vector potential is presented. These terms are essential in the context of 3D Lagrangian vortex particle methods combined with fast summation techniques. The...journal article 2016
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3D Lagrangian VPM: Simulations of the near-wake of an actuator disc and horizontal axis wind turbineBerdowski, T.J. (author), Ferreira, Carlos (author), Walther, J. (author)The application of a 3-dimensional Lagrangian vortex particle method has been assessed for modelling the near-wake of an axisymmetrical actuator disc and 3-bladed horizontal axis wind turbine with prescribed circulation from the MEXICO (Model EXperiments In COntrolled conditions) experiment. The method was developed in the framework of the open-...journal article 2016