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Brandetti, L. (author)
In urban areas, vertical-axis wind turbines (VAWTs) show promise due to their omnidirectional design, addressing challenges faced by traditional horizontal-axis turbines (HAWTs). Despite significant progress in urban VAWTs, extensive multidisciplinary research is needed to optimise their efficiency and use in such environments. <br/><br/>This...
doctoral thesis 2024
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Eijkelhof, D. (author), Buendía Vela, Gabriel (author), Schmehl, R. (author)
High aerodynamic efficiency is a key design driver for airborne wind energy systems as it strongly affects the achievable energy output. Conventional fixed-wing systems generally use aerofoils with a high thickness-to-chord ratio to achieve high efficiency and wing loading. The box wing concept suits thinner aerofoils as the load distribution...
journal article 2023
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Gutiérrez, R. (author), Zamponi, R. (author), Ragni, D. (author), Llorente, Elena (author), Aranguren, Patricia (author)
Modern wind turbines employ thick airfoils in the outer region of the blade with strong adverse pressure gradients and high sensitivity to flow separation, which can be anticipated by leading-edge roughness. However, Reynolds average Navier-Stokes simulations currently overpredict the Reynolds shear stresses near the surface, and the flow...
journal article 2023
document
Candeloro, Paolo (author), Ragni, D. (author), Pagliaroli, Tiziano (author)
In the last decade, the drone market has grown rapidly for both civil and military purposes. Due to their versatility, the demand for drones is constantly increasing, with several industrial players joining the venture to transfer urban mobility to the air. This has exacerbated the problem of noise pollution, mainly due to the relatively lower...
journal article 2022
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van Sluis, M. (author), Nasrollahi, S. (author), Gangoli Rao, A. (author), Eitelberg, G. (author)
The AeroCity is a new form of transportation concept that has been developed to provide high-speed ground transportation at a much lower cost than the existing high-speed railway. Utilizing the Wing-in-Ground (WIG) effect, the AeroCity vehicle does not require complex infrastructures like other contemporary concepts, such as the Hyperloop or...
journal article 2022
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van Nesselrooij, M. (author), van Campenhout, O.W.G. (author), van Oudheusden, B.W. (author), Schrijer, F.F.J. (author), Veldhuis, L.L.M. (author)
Accurately measuring small changes in aerodynamic drag over a flat surface stands at the core of the development of technologies capable of reducing turbulent friction drag. A wind tunnel drag measurement system was developed which improves significantly on the state of the art. Experimental tests demonstrated that an uncertainty of less than...
journal article 2022
document
Engler Faleiros, D. (author)
Particle Image Velocimetry (PIV) relies upon the introduction of particle tracers that scatter sufficient light and follow the flow accurately. The use of submillimetre helium-filled soap bubbles (HFSB) as flow tracers for PIV is investigated for the purpose of enabling velocity measurements in large-scale industrial wind tunnels. That soap...
doctoral thesis 2021
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Borobia-Moreno, R. (author), Ramiro-Rebollo, D. (author), Schmehl, R. (author), Sanchez Arriaga, G. (author)
The aerodynamic characteristics of a leading edge inflatable (LEI) kite and a rigid-framed delta (RFD) kite were investigated. Flight data were recorded by using an experimental setup that includes an inertial measurement unit, a GPS, a magnetometer, and a multi-hole Pitot tube onboard the kites, load cells at every tether, and a wind station...
journal article 2021
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Stokkermans, T.C.A. (author)
This research is on the aerodynamics of propellers in interaction. As a propeller is dependent on the flowfield it encounters, any disturbance in that inflow results in changes in loading on the propeller. This can result in propulsive efficiency changes and affect stability through generation of in-plane forces and out-of-plane moments. The...
doctoral thesis 2020
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Dighe, V.V. (author)
Ducted Wind Turbines (DWTs) are one of the many concepts that have been proposed to improve the energy extraction from wind in comparison to bare wind turbines. In reviewing the DWT studies, investigations based on the combined use of theoretical, computational, and experimental techniques have been presented. Although indicated in these studies...
doctoral thesis 2020
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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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Deng, S. (author)
The interest in Micro Air Vehicles (MAVs) has stimulated continuous research activities, in view of their potential in civilian and military applications. An autonomous MAV with dedicated onboard sensors would be capable of executing mission in closed environments, such as surveillance, in door inspection in support of rescue operations and...
doctoral thesis 2016
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Kuyt, C.B. (author), Greidanus, A.J. (author), Westerweel, J. (author)
The objective of this study was to determine the advantage of the application of speedstrips to rowing oars for a lightweight single sculler. The research method comprehended three steps: (1) the analysis of the rowing oar movement, (2) the determination of the change in drag and (3) the composition of a rowing model to establish the...
conference paper 2016
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Wang, Q. (author), Goosen, J.F.L. (author), van Keulen, A. (author)
Quasi-steady aerodynamic models play an important role in evaluating aerodynamic performance and conducting design and optimization of flapping wings. The kinematics of flapping wings is generally a resultant motion of wing translation (yaw) and rotation (pitch and roll). Most quasi-steady models are aimed at predicting the lift and thrust...
journal article 2016
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
Aerodynamic drag is computed from velocity measurements obtained with particle image velocimetry (PIV). This allows determining the drag force in combination with the visualization of the flow structures responsible for drag generation. Two experiments are conducted to illustrate the working principle of the approach, which is meant for...
journal article 2016
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Ubbens, H.H. (author), Dwight, R.P. (author), Sciacchitano, A. (author), Timmer, W.A. (author)
Bobsleighs races nowadays are decided upon hundredths of a second. As the margins are that small the aerodynamics of a bobsleigh can play a significant role in a race outcome. This paper investigates the influence of the gap between the nose and the rear cowling of a two-man bobsleigh. The paper especially focusses on the misalignment between...
journal article 2016
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Celis, Bert (author), Ubbens, Harm H. (author)
In order to overcome resistance a cyclist has to deliver a total power output of which 90% is necessary to overcome the aerodynamic drag [1,2]. In order to perform research in this aerodynamic drag a wind tunnel has been built by the Belgium company Flanders' Bike Valley. This wind tunnel is designed using classical design rules and with...
journal article 2016
document
Jansen, A.J. (author), Van Deursen, B. (author), Howe, C. (author)
The paper presents the effect of changes in sailing apparel on aerodynamic drag, starting from the assumption that drag reduction of sailing apparel will increase the speed of an Olympic class sailing boat (in this case the Laser, a single-handed Olympic dinghy), mainly on upwind courses. Due to the fact that literature on this specific subject...
journal article 2012
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Epema, H.K. (author), Van den Brand, S. (author), Gregoor, W. (author), Kooijman, J.D.G. (author), Pereboom, H.P. (author), Wielemaker, D.C. (author), Van der Zweep, C.J. (author)
The current International Human Powered Vehicle Association world records for faired bicycles stand at 133.284km/h for the 200m flying start speed record and 91.562 km for the hour record. Traditionally the recumbent bicycles that have been developed for breaking one of either of these records have been optimized around a specific, relatively...
journal article 2012
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