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Keijzer, D.M. (author), Simon Soria, C. (author), Arends, J.J. (author), Sarıgöl, B. (author), Scarano, F. (author), Castro, Saullo G.P. (author)
As of present the Urban Air Mobility market has been dominated by fully electric aircraft. However, hydrogen vehicles have remained relatively undeveloped in this segment, also because hydrogen poses additional design complexities and uncertainties concerning crashworthiness, fuel cell cooling, and low volumetric density. Nevertheless, hydrogen...
conference paper 2024
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Dekker, H.N.J. (author), Tuinstra, M (author), Baars, W.J. (author), Scarano, F. (author), Ragni, D. (author)
A semi-emperical model is developed, able to capture the aeropropulsive performance characteristics of Over-The-Wing propellers at incidence. The model is based on an hypothesis on the interactions of the propeller- and wing-induced flow fields. Effects of these interactions on the both the thrust and lift are written in a form in which the...
conference paper 2023
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Dekker, H.N.J. (author), Tuinstra, Marthijn (author), Baars, W.J. (author), Scarano, F. (author), Ragni, D. (author)
conference paper 2023
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Scarano, F. (author), Ujjaini Kempaiah, K. (author), Kotsonis, M. (author)
In the present work, planar and tomographic PIV are used to investigate how the organisation of wall turbulence is altered when actuators are operated with the objective of reducing the skin friction drag. When the wall is mechanically oscillated in the spanwise direction, high-resolution planar PIV enable the direct measurement of wall shear...
conference paper 2022
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Hysa, I. (author), Tuinstra, Marthijn (author), Lammers, K (author), Scarano, F. (author), Sciacchitano, A. (author), Gebbink, Roy (author), Harrison, C (author)
Volumetric PIV measurements are performed to study the flow development around a 1:12 scale model of a thrust reverser in a low-speed wind tunnel. The thrust-reverser operates in a freestream flow of 3-5 m/s and with a jet to freestream velocity ratio Vjet/Vinf ranging from 1.5 to 6. Making use of sub-millimeter helium-filled soap bubbles, large...
conference paper 2022
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)
The aerodynamic characteristics of a modern road cycling wheel in crosswind are studied through force measurements and 3D velocimetry in TU Delft’s Open Jet Facility. The performance of the 62 mm deep rim is evaluated for two tire profiles, and yaw angles up to 20◦ . All measurements are executed at 12.5 m/s (45 km/h) freestream- and wheel...
conference paper 2021
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Engler Faleiros, D. (author), Tuinstra, Marthijn (author), van Rooijen, Bart D. (author), Scarano, F. (author), Sciacchitano, A. (author)
This work evaluates the use of helium-filled soap bubbles (HFSB) for Particle Image Velocimetry (PIV) measurements at high Reynolds numbers (up to 3.2 million) in aeronautics. The measurements are performed in the Low Speed Tunnel (LST) of the German-Dutch Wind Tunnels (DNW) using a high-lift airfoil in close-to-stall conditions up to 70 m/s....
conference paper 2019
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Jux, C. (author), Scarano, F. (author), Sciacchitano, A. (author)
A multi-model method for static pressure evaluations based on 3D PTV data is presented. The volumetric measurement domain is partitioned into an irrotational part where pressure is evaluated in a point-wise manner through Bernoulli’s equation, and a rotational domain where the pressure gradient is spatially integrated. In a third step, the field...
conference paper 2019
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Saredi, E. (author), Sciacchitano, A. (author), Scarano, F. (author)
A novel approach is introduced to enlarge the range of measurable velocities by PTV systems. The approach relies upon the acquisition of two or more sets of double-frame images with increasing pulse separation time Δt. The underlying principle is that measurements with a short Δt yield a velocity field with high percentage of valid vectors, but...
conference paper 2019
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Gonzalez Saiz, G. (author), Sciacchitano, A. (author), Scarano, F. (author)
The time-segment assimilation (TSA) method levers upon the spatio-temporal information from a finite number of successive time samples of particle velocity, coming from PTV and STB, into a refined spatial reconstruction of the velocity field of the flow. The method recently introduced by Schneiders and Scarano (2018) is elaborated here further...
conference paper 2019
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
A new approach is introduced to evaluate the potential drag reduction by skin suit design in speed sport. The approach relies upon local flow information measured in the wake of a cyclist mannequin. Lagrangian Particle Tracking is employed to measure the distribution of time-average streamwise velocity in a cross-plane of 30 × 100 cm2 behind the...
conference paper 2018
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)
Some recent trends in the development of PIV techniques are leading to the realization of velocity measurement at large scale. Moreover, methods for evaluating the fluid flow pressure from PIV data have been successfully demonstrated at small scale and for simple geometries. Methods for quantitative visualization of surface flow properties such...
conference paper 2018
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Sciacchitano, A. (author), Giaquinta, Daniele (author), Schneiders, J.F.G. (author), Scarano, F. (author), van Rooijen, B.D. (author), Funes, D.E. (author)
The flow field around a turboprop aircraft scaled model is investigated with attention to the propeller slipstream and the wing near wake. The experiments are conducted in the Low-Speed Tunnel (LST) of the German-Dutch Wind Tunnels (DNW) as part of a collaboration among DNW, Delft University of Technology and Airbus. Quantitative flow...
conference paper 2018
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Engler Faleiros, D. (author), Tuinstra, Marthijn (author), Sciacchitano, A. (author), Scarano, F. (author)
The operating regimes of an orifice-type helium-filled soap bubbles (HFSB) generator are investigated to characterize the properties of the resulting tracers. The geometrical properties of the bubbles as well as the production rate are studied with high-speed shadowgraphy. The weight of the tracers relative to the mass of displaced air is...
conference paper 2018
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Spoelstra, A.M.C.M.G. (author), de Martino Norante, Luigi (author), Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
A procedure is proposed to reconstruct the instantaneous velocity field from full particle trajectories in a data assimilation framework that includes the vorticity transport equation. The technique is christened as time-segment assimilation (TSA). The work addresses the common problem of low seeding concentration in 3D experiments, usuallThe...
conference paper 2018
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Schneiders, J.F.G. (author), Scarano, F. (author)
A procedure is proposed to reconstruct the instantaneous velocity field from full particle trajectories in a data assimilation framework that includes the vorticity transport equation. The technique is christened as time-segment assimilation (TSA). The work addresses the common problem of low seeding concentration in 3D experiments, usually...
conference paper 2018
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author), van Oudheusden, B.W. (author)
The accuracy of the “PIV wake rake” method to measure the drag of transiting objects is evaluated. Tomographic Particle Image Velocimetry measurements are conducted on a sphere towed at different speeds, within a Reynolds number range where the drag coefficient is constant. In contrast to PIV wake rake application on steady models in wind...
conference paper 2018
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Ye, Q. (author), Schrijer, F.F.J. (author), Scarano, F. (author)
The transitional flow features over and downstream of isolated roughness elements in hypersonic flow are investigated by means of infrared thermography. The local heat flux distribution in the wake of the roughness element reveals the footprint of multiple streamwise counter-rotating vortex pairs. The formation of a turbulent wedge with the...
conference paper 2016
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Ye, Q. (author), Schrijer, F.F.J. (author), Scarano, F. (author)
The transitional flow features past a micro-ramp are investigated in the incompressible flow regime at critical and supercritical roughness-height based Reynolds number (Reh). Tomographic PIV is adopted as the diagnostic technique to identify the instantaneous three-dimensional flow behaviour in the domain of 73 ramp height streamwise. The...
conference paper 2016
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Morias, Koen (author), Caridi, Giuseppe Carlo Alp (author), Sciacchitano, A. (author), Scarano, F. (author)
The present work follows a previous study on the aerodynamic characterization of helium-filled soap bubbles (HFSBs) for large-scale PIV measurements. HFSBs were found to yield, on average, a time response of about 10s. However, the response of each individual tracer remained to be ascertained, which is the topic of the present study. The...
conference paper 2016
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