Searched for: author:"Ferreira, Carlos"
(1 - 20 of 30)

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Melani, P. F. (author), Balduzzi, F. (author), Brandetti, L. (author), Ferreira, Carlos (author), Bianchini, A. (author)
Simulation methods ensuring a level of fidelity higher than that of the ubiquitous Blade Element Momentum theory are increasingly applied to VAWTs, ranging from Lifting-Line methods, to Actuator Line or Computational Fluid Dynamics (CFD). The inherent complexity of these machines, characterised by a continuous variation of the angle of attack...
journal article 2020
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Brandetti, L. (author), De Tavernier, D.A.M. (author), Leblanc, B.P. (author), Ferreira, Carlos (author)
The paper presents an experimental study of applying variable loads on a vertical-axis wind turbine (VAWT). The experiment is conducted in an open-jet wind tunnel on a two-bladed Darrieus VAWT equipped with active individual blade pitch control. Variable loads are achieved by dynamically changing the pitch angle of the individual blades and...
journal article 2020
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De Tavernier, D.A.M. (author), Ferreira, Carlos (author), Paulsen, U. (author), Madsen, H. (author)
This paper deals with the 3D effects of a vertical-axis wind turbine caused by the tip vortices. In this study, the VAWT rotor is simplified by the infinitely bladed actuator cylinder concept. The loads are prescribed to be uniform and normal to the surface and are distributed between the upwind and downwind half. Depending on the load...
journal article 2020
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De Tavernier, D.A.M. (author), Sakib, M. (author), Griffith, D.T. (author), Pirrung, G. (author), Paulsen, U. (author), Madsen, H. (author), Keijer, W. (author), Ferreira, Carlos (author)
Since the first commercial projects, the development of vertical-axis wind turbines (VAWTs) has been impeded by the limited understanding and inability to accurately model VAWTs. This paper investigates and compares different aerodynamic modelling techniques for VAWTs in 3D. All considered models are using the same blade-element...
journal article 2020
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de Tavernier, D.A.M. (author), Ferreira, Carlos (author)
This paper presents a new dynamic inflow model for vertical-axis wind turbines (VAWTs). The model uses the principle of Duhamel's integral. The indicial function of the inflow- and crossflow-induction required to apply Duhamel's integral is represented by an exponential function depending on the thrust coefficient and the azimuthal position....
journal article 2020
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de Tavernier, D.A.M. (author), Viré, A.C. (author), Ferreira, Carlos (author)
In this work, we demonstrate to what extent it is possible to use load optimisation to aerodynamically damp the floater motion of vertical-axis wind turbines. The loadform of a VAWT can be altered to the desired objective using an individual blade-pitch schedule. A coupled hydro- and aerodynamic simulation tool is built solving the equation...
journal article 2020
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Huang, M. (author), Ferreira, Carlos (author), Sciacchitano, A. (author), Scarano, F. (author)
Wind tunnel experiments on a scaled vertical axis wind turbine (VAWT) and square porous plate with a porosity of 64% are conducted in the W-tunnel of TU-Delft. The VAWT thrusts in axial and lateral directions are measured with an in-house load cell system based on moment conservation. Wake of the VAWT in tip speed ratio of 1.5 and 2.5 and the...
journal article 2020
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Leblanc, B.P. (author), Ferreira, Carlos (author)
A digital twin can be described as a digital replica of a physical asset. The use of such models is key to understanding complex loading phenomena experienced during testing of vertical axis wind turbines. Unsteady aerodynamic and structural effects such as dynamic stall and dynamically changing thrust and blade loading are difficult to...
journal article 2020
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Leblanc, B.P. (author), Ferreira, Carlos (author)
The aerodynamic loading of a vertical axis wind turbine varies with the azimuth position of the blades. The thrust of the VAWT can be computed as a decomposition of the normal force on each of the blades. By varying the blade loading as a function of turbine azimuth, it is possible to vary the direction of the average thrust of the turbine....
journal article 2020
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Yu, W. (author), De Tavernier, D.A.M. (author), Ferreira, Carlos (author), van Kuik, G.A.M. (author), Schepers, J.G. (author)
Two new engineering models are presented for the aerodynamic induction of a wind turbine under dynamic thrust. The models are developed using the differential form of Duhamel integrals of indicial responses of actuator disc type vortex models. The time constants of the indicial functions are obtained by the indicial responses of a linear and...
journal article 2019
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De Tavernier, D.A.M. (author), Ferreira, Carlos (author)
This paper investigates the need for dynamic inflow models for vertical axis wind turbines (VAWTs). The approach is two-fold. First, dynamic inflow is realised by dynamic thrust on an actuator disk in OpenFOAM. The induction phase shift and amplitude showed a significant dependency on the streamwise location. Second, a reference turbine in...
journal article 2019
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Dong, J. (author), Viré, A.C. (author), Ferreira, Carlos (author), Li, Zhangrui (author), van Bussel, G.J.W. (author)
A modified free-wake vortex ring model is proposed to compute the dynamics of a floating horizontal-axis wind turbine, which is divided into two parts. The near wake model uses a blade bound vortex model and trailed vortex model, which is developed based on vortex filament method with straight lifting lines assumption. By contrast, the far...
journal article 2019
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de Tavernier, D.A.M. (author), Ferreira, Carlos (author)
In this paper, the actuator-in-actuator cylinder (AC-squared) model is presented. This model is an extension of the original actuator cylinder model of Madsen and is capable of modelling the effect of a two concentric actuation surfaces in 2D. The induced velocity at every point in the 2D field is affected by the force field acting on the two...
journal article 2019
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de Tavernier, D.A.M. (author), Ferreira, Carlos (author), van Bussel, G.J.W. (author)
To advance the design of a multimegawatt vertical-axis wind turbine (VAWT), application-specific airfoils need to be developed. In this research, airfoils are tailored for a VAWT with variable pitch. A genetic algorithm is used to optimise the airfoil shape considering a balance between the aerodynamic and structural performance of airfoils. At...
journal article 2019
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Mendoza, Victor (author), Bachant, Peter (author), Ferreira, Carlos (author), Goude, Anders (author)
In the present work, the near-wake generated for a vertical axis wind turbine (VAWT) was simulated using an actuator line model (ALM) in order to validate and evaluate its accuracy. The sensitivity of the model to the variation of the spatial and temporal discretization was studied and showed a bigger response to the variation in the mesh size...
journal article 2019
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Dong, J. (author), Viré, A.C. (author), Ferreira, Carlos (author), Li, Zhangrui (author), van Bussel, G.J.W. (author)
A modified free-wake vortex ring model is proposed to compute the dynamics of a floating horizontal-axis wind turbine, which is divided into two parts. The near wake model uses a blade bound vortex model and trailed vortex model, which is developed based on vortex filament method with straight lifting lines assumption. By contrast, the far wake...
journal article 2019
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Khan, Muhammad A. (author), Ferreira, Carlos (author), Schepers, J.G. (author), Sørensen, Niels N. (author)
Spectral analysis was performed on the time series data computed from pressure measurements on the New MEXICO (Model Rotor Experiments under Controlled Conditions) rotor in standstill conditions. As a priori, 3D airfoil polars were recreated from standstill measurements and compared against 2D airfoil polars and flat plate theory results to...
journal article 2019
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Vimalakanthan, K. (author), Schepers, J.G. (author), Shen, W. Z. (author), Rahimi, H. (author), Micallef, D. (author), Ferreira, Carlos (author), Jost, E. (author), Klein, L. (author)
As part of the AVATAR and Mexnext projects, this study compares several methods used to derive lifting line variables from CFD simulations of the MEXICO rotor in yawed inflow. The results from six partners within the AVATAR/Mexnext consortium using five different methods of extraction were compared. Overall comparison of the induced...
journal article 2018
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Schepers, J.G. (author), Boorsma, K. (author), Sorensen, N. (author), Voutsinas, V. (author), Sieros, G. (author), Rahimi, H. (author), Heisselmann, H. (author), Jost, E. (author), Lutz, T. (author), Maeder, T. (author), Gonzalez, A. (author), Ferreira, Carlos (author), Stoevesandt, B. (author), Barakos, G. (author), Lampropoulos, N. (author), Croce, A. (author), Madsen, J. (author)
This paper presents final 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. Special attention is paid to the improvement of low fidelity engineering (BEM based) models with higher fidelity (CFD) models but also with intermediate fidelity free vortex wake ...
journal article 2018
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Leblanc, B.P. (author), Ferreira, Carlos (author)
Large floating offshore wind turbines are beginning to show promise as a technology with several pilot projects being completed in recent years with more on the near horizon. Due to the complexities of the floating configuration there are substantial costs associated with the platform and mooring systems for these types of deep water machines...
journal article 2018
Searched for: author:"Ferreira, Carlos"
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