Searched for: subject%3A%22actuator%255C%2Bdisc%22
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document
van Neerbos, Tom (author)
The main objective of this master’s thesis is to experimentally investigate the effects of dynamic inflow conditions on the wake of an actuator disc. Dynamic inflow is the unsteady wake in momentum theory. Dynamic inflow can experimentally be generated by a gust generator. During the experiments, in which Particle Image Velocimetry (PIV) was...
master thesis 2022
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Huang, M. (author), Ferreira, Carlos (author), Sciacchitano, A. (author), Scarano, F. (author)
The wake recovery from planar porous actuators that surrogate the effect of wind turbines is investigated, focusing on rectangular shapes for vertical axis wind turbines (VAWTs). We proposed an effective mixing diameter D∗ to scale the streamwise momentum recovery for actuators of arbitrary shape. The length-scale D∗ is given by the ratio...
journal article 2022
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Hur, C. (author), Ferreira, Carlos (author), Schepers, Gerard (author)
Horizontal axis wind turbines (HAWTs) experience yaw misalignments due to the physical limitations of yaw controllers and various novel active yaw controls. Moreover, the motion of floating offshore wind turbines (FOWTs) accelerates yaw misalignment. The blade element momentum (BEM) method is widely used due to its computational efficiency for...
journal article 2022
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Sala, Arianna (author)
As the need for abundant and reliable renewable energy increases, there is a growing interest in floating wind turbines, which would allow to harness the wind resource in areas where bottom-founded wind turbines cannot be used. However, the movements of the platform are expected to cause unsteady aerodynamics effects, including different wake...
master thesis 2021
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Yu, W. (author), De Tavernier, D. (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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van der Deijl, Wessel (author)
In the case of unsteady loading conditions at a rotor, the induced velocity response lags the thrust coefficient at the rotor. The two parameters that are responsible for unsteady loading conditions are rotor thrust (due to blade pitch, or rotational speed) and incoming wind speed. The induced velocity response to these two sources of...
master thesis 2018
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Yu, W. (author)
Blade Element Momentum (BEM) is the most important aerodynamic analysis method for wind turbines. BEM is derived assuming stationary conditions, which limits its ability to model the unsteady aerodynamic effects. This becomes increasingly relevant for the flexible blades of current large-scale turbines, and the employment of passive and active...
doctoral thesis 2018
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Khajehzadeh, Arash (author)
This project aims to investigate propeller wing interaction of an over the wing (OTW) based distributed propulsion (DP) system with the addition of a secondary wing. This research explored the opportunities that OTW configuration provides to DP concept, such as improving the lifting performance of system by inducing the flow over the upper...
master thesis 2018
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Kaur, karanbir (author)
Experimental Analysis of an Actuator Disk under cyclic unsteady loading.<br/>Wind Energy is one of the cleanest forms of energy. It does not contribute to the greenhouse gases and is also one of the least expensive forms of renewable energy. Due to this, number of wind turbines are increasing annually. Therefore, it is crucial to understand the...
master thesis 2017
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Yu, W. (author), Ferreira, Carlos (author), van Kuik, G.A.M. (author), Baldacchino, D. (author)
Although the Blade Element Momentum method has been derived for the steady conditions, it is used for unsteady conditions by using corrections of engineering dynamic inflow models. Its applicability in these cases is not yet fully verified. In this paper, the validity of the assumptions of quasi-steady state and annuli independence of the blade...
journal article 2016
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Tang, J. (author), Avallone, F. (author), van Bussel, G.J.W. (author)
This study presents an experimental investigation on a diffuser augmented wind turbine (DAWT). A screen mesh is used to simulate the energy extraction mechanisms of a wind turbine in experiment. Different screen porosities corresponding to different turbine loading coefficients are tested. Measurements of the axial force and of the velocity...
journal article 2016
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Abolghasemi, M.A. (author), Piggott, M.D. (author), Spinneken, J (author), Viré, A.C. (author), Cotter, CJ (author), Crammond, S. (author)
Embedding tidal turbines within simulations of realistic large-scale tidal flows is a highly multi-scale problem that poses significant computational challenges. Here this problem is tackled using actuator disc momentum (ADM) theory and Reynolds-averaged Navier–Stokes (RANS) with, for the first time, dynamically adaptive mesh optimisation...
journal article 2016
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Dighe, V.V. (author), Avallone, F. (author), van Bussel, G.J.W. (author)
In this paper, a computational approach, based on the solution of Reynolds-averaged-Navier–Stokes (RANS) equations, to describe the flow within and around a diffuser augmented wind turbine (DAWT) is reported. In order to reduce the computational cost, the turbine is modeled as an actuator disc (AD) that imposes a resistance to the passage of the...
journal article 2016
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Lignarolo, L. (author), Ragni, D. (author), Simao Ferreira, C.J. (author), van Bussel, G.J.W. (author)
The present paper is the summary of 3 years of research on the wake aerodynamics of horizontal axis wind turbine at Delft University of Technology, the Netherlands. In particular, the main results and the conclusions of two experimental campaigns are collected. The underlying research question is: how do the near-wake turbulent flow structures...
conference paper 2015
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Abolghasemi, A. (author), Piggott, M.D. (author), Spinneken, J. (author), Vire, A. (author), Cotter, C.J. (author)
A versatile numerical model for the simulation of flow past horizontal axis tidal turbines has been developed. Currently most large-scale marine models employed to study marine energy use the shallow water equations and therefore can fail to account for important turbulent physics. The model presented here is based on actuator disc momentum (ADM...
conference paper 2015
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Van Kuik, G.A.M. (author), Van Zuijlen, A.H. (author)
Actuator disc calculations can be divided in two categories: force models where, for a prescribed force field, the flow is calculated using a CFD method, and kinematic models, where the wake is calculated based on wake boundary conditions and the force field is known when the velocities are known. In both categories, but specifically for the...
conference paper 2009
Searched for: subject%3A%22actuator%255C%2Bdisc%22
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