Searched for: department%3A%22Flow%255C%2BPhysics%255C%2Band%255C%2BTechnology%22
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Nederlof, R. (author), Kooij, R.N.F. (author), Veldhuis, L.L.M. (author), Sinnige, T. (author)
With the rise of distributed propeller concepts, there is an increased interest in quantifying the interaction between propeller slipstream and wing. It is known from literature that the local upwash induced by the propeller swirl can lead to a reduction of the wing-induced drag, a phenomenon often referred to as swirl recovery. However, at the...
conference paper 2023
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)
The aerodynamic characteristics of a modern road cycling wheel in cross wind are studied through force- and planar PIV measurements in the TU Delft Open Jet Facility. The performance of the 62 mm deep rim is evaluated for three tire profiles, and yaw angles up to 24°. All measurements are executed at 12.5 m/s (45 km/h) freestream- and wheel...
journal article 2023
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Huang, M. (author), Sciacchitano, A. (author), Ferreira, Carlos (author)
Wake losses are a critical consideration in wind farm design. The ability to steer and deform wakes can result in increased wind farm power density and reduced energy costs and can be used to optimize wind farm designs. This study investigates the wake deflection of a vertical axis wind turbine (VAWT) experimentally, emphasizing the effect of...
journal article 2023
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Boatto, Umberto (author), Bonnet, Paul A. (author), Avallone, F. (author), Ragni, D. (author)
Blade Element Momentum Theory (BEMT) -based approaches provide 15%–20% inaccurate load predictions under uniform steady inflow. Inaccuracies were related to unclear aerodynamic mechanisms causing the Prandtl Tip-Root Loss (TRL) correction to fail at high Tip-Speed Ratio (TSR) and the ambiguous drag coefficient treatment under Stall Delay (SD)...
journal article 2023
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Tambe, S.S. (author), Schrijer, F.F.J. (author), Gangoli Rao, A. (author), Veldhuis, L.L.M. (author)
Boundary-layer instability on a rotating cone induces coherent spiral vortices that are linked to the onset of laminar–turbulent transition. This type of transition is relevant to several aerospace systems with rotating components, e.g., aeroengine nose cones. Because a variety of options exist for the nose-cone shapes, it is important to...
journal article 2023
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Duivenvoorden, R.R. (author), Suard, Noah (author), Sinnige, T. (author), Veldhuis, L.L.M. (author)
Experiments were performed using a wall-to-wall unswept and untapered wing with a single slotted flap and a propeller, to obtain a validation dataset and gain insight into primary flow phenomena in propeller-wing-flap interactions. Measurements were taken using pressure taps, a wake rake and oil flow visualization, for several flap...
conference paper 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
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Ragni, D. (author), Avallone, F. (author), Casalino, D. (author)
Sustainability has encouraged studies focusing on lowering the aeroacoustic impact of new aerodynamically optimized mechanical systems for several applications in wind-energy, aviation, automotive and urban air-mobility. The deployment of effective noise-reduction strategies starts with a deep understanding of the underlying mechanisms of...
review 2022
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Hehner, Marc T. (author), Gatti, Davide (author), Kotsonis, M. (author), Kriegseis, Jochen (author)
Two different plasma actuation strategies for producing near-wall flow oscillations, namely the burst-modulation and beat-frequency mode, are characterized with planar particle image velocimetry in quiescent air. Both concepts are anticipated to work as non-mechanical surrogates of oscillating walls aimed at turbulent flow drag reduction,...
journal article 2022
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Tambe, S.S. (author), Schrijer, F.F.J. (author), Veldhuis, L.L.M. (author), Gangoli Rao, A. (author)
This work shows the behaviour of an unstable boundary-layer on rotating cones in high-speed flow conditions: high Reynolds number Rel > 106, low rotational speed ratio S < 1–1.5, and inflow Mach number M = 0.5. These conditions are most-commonly encountered on rotating aero-engine-nose-cones of transonic cruise aircraft. Although it has...
journal article 2022
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Finger, D. Felix (author), de Vries, R. (author), Vos, Roelof (author), Braun, Carsten (author), Bil, Cees (author)
The number of studies on hybrid-electric aircraft is steadily increasing because these configurations can lead to lower operating costs and environmental impact than traditional aircraft. However, due to the lack of reference data of actual hybrid-electric aircraft, the design tools and results are difficult to validate. This paper analyzes...
journal article 2022
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Bresciani, A. P.C. (author), Boatto, U. (author), Le Bras, S. (author), Bonnet, P. (author), De Santana, L. D. (author)
This paper establishes the effect of blade deflections on wind turbine noise directivity. Fast turn-around methods are used in a framework of integrated aeroelastic and aeroacoustic simulations: the blade element momentum theory is coupled with a RANS-informed Amiet's model for the aeroacoustic modelling of trailing-and leading-edge noise....
journal article 2022
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Mazza, F. (author), Griffioen, N. (author), Castellanos, Leonardo (author), Klyukin, Dmitry (author), Bohlin, G.A. (author)
We present ultrabroadband two-beam femtosecond/picosecond coherent Raman spectroscopy on the ro-vibrational spectra of CO<sub>2</sub> and O<sub>2</sub>, applied for multispecies thermometry and relative concentration measurements in a standard laminar premixed hydrocarbon flame. The experimental system employs fs-laser-induced filamentation...
journal article 2022
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Saredi, E. (author), Tumuluru Ramesh, Nikhilesh (author), Sciacchitano, A. (author), Scarano, F. (author)
State observer techniques are investigated for the assimilation of three-dimensional velocity measurements into computational fluid dynamics simulations based on Reynolds-averaged Navier–Stokes (RANS) equations. The method relies on a forcing term, or observer, in the momentum equation, stemming from the difference between the computed velocity...
journal article 2021
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Scarano, F. (author), Jux, C. (author), Sciacchitano, A. (author)
The present work reviews the recent developments in the domain of particle image velocimetry (PIV) with attention to its use for large-scale problems of interest for industrial aerodynamics. The article introduces the fundamental principles of flow seeding for large-scale experiments based on the helium-filled soap bubble (HFSB) technique....
journal article 2021
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)
Abstract: A method to identify the surface of solid models immersed in fluid flows is devised that examines the spatial distribution of flow tracers. The fluid–solid interface is associated with the distance from the center of a circle to the centroid of the tracers ensemble captured within it. The theoretical foundation of the method is...
journal article 2021
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Sivanandan, H. (author), Kishore, V. Ratna (author), Goel, Mukesh (author), Asthana, Abhishek (author)
The dispersion of air pollutants emitted from industries has been studied ever since the dawn of industrialisation. The present work focuses on investigating the effect of negative atmospheric temperature gradient and the plume stack orientation of two individual equal-height stacks on the vertical rise and dispersion of the plume. The study...
journal article 2021
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Casalino, D. (author), Grande, E. (author), Romani, G. (author), Ragni, D. (author), Avallone, F. (author)
Experimental and numerical results of a propeller of 0.3 m diameter operated in quiescent standard ambient conditions at 5000 RPM and axial velocity ranging from 0 to 20 m/s and advance ratio ranging from 0 to 0.8 are presented as a preliminary step towards the definition of a benchmark configuration for low Reynolds number propeller...
journal article 2021
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van Arnhem, N. (author), de Vries, R. (author), Sinnige, T. (author), Vos, Roelof (author), Veldhuis, L.L.M. (author)
In this combined experimental and numerical study, the propeller–airframe aerodynamic interaction is characterized for an aircraft configuration with propellers mounted to the horizontal tailplane. The contributions of the propeller and airframe to the overall loading are distinguished in the experimental analyses by using a combination of...
journal article 2021
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)
An experimental approach for the measurement of the time-average fluid flow pressure over the surface of generic three-dimensional objects is presented. The method is based on robotic volumetric PTV measurements followed by the integration of the pressure gradient. The domain for pressure evaluation is subdivided in two parts: in the...
journal article 2020
Searched for: department%3A%22Flow%255C%2BPhysics%255C%2Band%255C%2BTechnology%22
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