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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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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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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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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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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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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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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
Experiments are conducted that obtain the aerodynamic drag of a sphere towed within a rectangular duct from PIV. The drag force is obtained invoking the time-average momentum equation within a control volume in a frame of reference moving with the object. The sphere with 0.1 m diameter is towed at velocity of 1.5 m/s, corresponding to Re = 10...
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, K.L.L. (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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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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Gentile, V. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author), Scarano, F. (author)
The backflow instability in the wake past a cylindrical blunt-based body in pitch is investigated at a Reynolds number ReD = 6.7 · 104 based on the cylinder diameter. Time-resolved stereoscopic particle image velocimetry measurements have been performed in a cross-flow plane located 0.3 D downstream of the model base. An increasing displacement...
conference paper 2016
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Schneiders, J.F.G. (author), Scarano, F. (author), Elsinga, G.E. (author)
conference paper 2016
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Gentile, V. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author), Scarano, F. (author)
The so-called very-low-frequency (VLF) azimuthal meandering of the reversed-flow region has been shown to contribute significantly to the unsteadiness of the turbulent wake flow past a bluff body of revolution (Rigas et al. 2014; Grandemange et al. 2014). Such an erratic behavior causes a continuous change in the wake topology and, particularly...
conference paper 2016
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
Experiments are conducted to determine the drag of a full-scale cyclist model in a wind tunnel at 4 m/s. The aerodynamic drag is evaluated from tomo-PIV measurements in the wake of the model applying the conservation of momentum within a control volume. The measurements are conducted in a thin volume of 100 x 170 x 3 cubic centimeters using...
conference paper 2016
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Schneiders, J.F.G. (author), Scarano, F. (author)
The manuscripts presents the working principle of a novel technique to interpolate sparse and scattered particle tracking velocimetry (PTV) measurements onto a dense grid, by using the velocity measurements along a full particle trajectory. The method performs iteratively a vortex-in-cell simulation (Schneiders et al. 2014 in Exp Fluids 55:1692)...
conference paper 2016
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
Large-scale tomographic Particle Image Velocimetry is proposed as a tool for the on-site aerodynamic investigation in speed sports. The ring-of-fire concept is presented, which relies upon a tomographic PIV system used during the training of athletes in speed sports. The system consists of a short tunnel installed in a velodrome, through which...
conference paper 2015
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Sciacchitano, A. (author), Caridi, G. (author), Scarano, F. (author)
Aerodynamics plays a crucial role in many speed sports, where races are often won by fractions of a second. A thorough understanding of the flow field around an athlete is of paramount importance to optimize the athletes’ posture, garment roughness and equipment shape to achieve the minimum aerodynamic drag and maximum velocity. To date,...
conference paper 2015
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Schneiders, J.F.G. (author), Caridi, G. (author), Sciacchitano, A. (author), Scarano, F. (author)
conference paper 2015
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Schneiders, J.F.G. (author), Azijli, I. (author), Scarano, F. (author), Dwight, R.P. (author)
A method is proposed to reconstruct instantaneous velocity from time-resolved tomographic PTV, employing both instantaneous velocity and velocity material derivative. This improves upon current techniques by not only including penalization of velocity divergence, but also requiring consistency with the temporal derivative of the PTV particle...
conference paper 2015
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