Searched for: department%3A%22Aerodynamics%252C%255C%2BWind%255C%2BEnergy%255C%2B%2526%255C%2BPropulsion%22
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Rius Vidales, A.F. (author), Kotsonis, M. (author)
The impact of a forward-facing step (FFS) on the development of stationary crossflow instability is investigated on a swept wing model in a low-turbulence wind tunnel at chord Reynolds number of. Infrared thermography and particle image velocimetry measurements are used to quantify the transition location and growth of the crossflow...
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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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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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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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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Lasagna, D. (author), Buxton, O. R.H. (author), Fiscaletti, D. (author)
To investigate the influence of the orifice geometry on near-field coherent structures in a jet, Fourier proper orthogonal decomposition (Fourier-POD) is applied. Velocity and vorticity snapshots obtained from tomographic particle image velocimetry at the downstream distance of two equivalent orifice diameters are analyzed. Jets issuing from...
journal article 2021
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Teruna, C. (author), Avallone, F. (author), Ragni, D. (author), Rubio Carpio, A. (author), Casalino, D. (author)
Lattice Boltzmann simulations were carried out to investigate the noise mitigation mechanisms of a 3-D printed porous trailing-edge insert, elucidating the link between noise reduction and material permeability. The porous insert is based on a unit cell resembling a lattice of diamond atoms. It replaces the last 20 % chord of a NACA 0018 at...
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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della Corte, B. (author), van Sluis, M. (author), Gangoli Rao, A. (author), Veldhuis, L.L.M. (author)
View Video Presentation: https://doi-org.tudelft.idm.oclc.org/10.2514/6.2021-2467.vid<br/><br/>Boundary Layer Ingestion (BLI) is a technology that promises fuel consumption benefits for future civil aircraft. However, it introduces detrimental aerodynamic interactions between the propulsor and the airframe. In particular, the inflow to the BLI...
conference paper 2021
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de Vries, R. (author), van Arnhem, N. (author), Sinnige, T. (author), Vos, Roelof (author), Veldhuis, L.L.M. (author)
This article describes an experimental investigation of the aerodynamic interaction that occurs between distributed propellers in forward flight. To this end, three propellers were installed in close proximity in a wind tunnel, and the changes in their performance, flow-field characteristics, and noise production were quantified using...
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
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Saredi, E. (author), Sciacchitano, A. (author), Scarano, F. (author)
A novel approach is investigated to extend the range of measurable velocities by 3D-PTV systems. The method is specifically conceived for robotic volumetric PTV measurements, but it has applications for other similar techniques. The multi-Δt method relies upon combining the information from two or more sets of double-frame images with pulse...
journal article 2020
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Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)
The Reynolds number effects on body limbs of a cyclist model, namely leg and arm, are investigated via robotic volumetric Particle Image Velocimetry measurements in the velocity range from 5 ​m/s to 25 ​m/s. The near wakes of such body limbs feature recirculation regions whose width and length are governed not only by the taper of the body...
journal article 2020
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Lima Pereira, L.T. (author), Ragni, D. (author), Avallone, F. (author), Scarano, F. (author)
Abstract: Measurements of distributed surface pressure fluctuations over trailing-edge serrations at a Reynolds number Re <sub>θ</sub> = 4900 are performed with time-resolved 3D particle imaging velocimetry using helium filled soap bubbles as flow tracers. The sparse velocity vector field obtained with Lagrangian particle tracking is densely...
journal article 2020
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Spoelstra, A.M.C.M.G. (author), Hirsch, Maximilian (author), Sciacchitano, A. (author), Scarano, F. (author)
The Ring of Fire (RoF) measurement concept to perform on-site experiments of aerodynamic drag for transiting objects is investigated with a study that identifies the main sources of uncertainty. The main contributors to the uncertainty of the drag measurement are examined for the case of a cyclist riding through the measurement domain. A...
journal article 2020
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Ujjaini Kempaiah, K. (author), Scarano, F. (author), Elsinga, G.E. (author), van Oudheusden, B.W. (author), Bermel, Leon (author)
The reduction of turbulent skin-friction drag and the response of vortical structures in a zero-pressure gradient, turbulent boundary layer subjected to spanwise wall oscillation is investigated using planar and tomographic particle image velocimetry (PIV). The experiments are conducted at a momentum based Reynolds number of 1000, while the...
journal article 2020
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Huang, M. (author), Ferreira, Carlos (author), Sciacchitano, A. (author), Scarano, F. (author)
Wind tunnel experiments on a scaled vertical axis wind turbine (VAWT) and square porous plate with a porosity of 64% are conducted in the W-tunnel of TU-Delft. The VAWT thrusts in axial and lateral directions are measured with an in-house load cell system based on moment conservation. Wake of the VAWT in tip speed ratio of 1.5 and 2.5 and the...
journal article 2020
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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)
Abstract: The Ring of Fire (RoF) measurement concept, introduced by Terra et al. (Exp Fluids 58:83. https://doi.org/10.1007/s00348-017-2331-0, 2017; Experiments in Fluids 59:120, 2018), is applied to real cyclists to enable the aerodynamic drag determination during sport action. This principle is based on large-scale stereoscopic particle...
journal article 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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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
Searched for: department%3A%22Aerodynamics%252C%255C%2BWind%255C%2BEnergy%255C%2B%2526%255C%2BPropulsion%22
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