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Lorenzoni, V. (author), Violato, D. (author), Scarano, F. (author)
Time-resolved Tomographic PIV was used to characterize the flow around the leading edge of a NACA 0012 airfoil in rod-airfoil configuration at ReD = 3500. The volumetric approach at relatively high temporal resolution allows the measurement of the evolution of the 3D vortical structures constituting the Karman wake of the rod at interaction with...
conference paper 2010
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Violato, D. (author), Bryon, K. (author), Moore, P. (author), Scarano, F. (author)
This paper describes an experimental investigation by time-resolved planar and tomographic PIV on the sound production mechanism of vortex pairing of a transitional water-jet flow at Re=5000. The shear layer is characterized by axisymmetric vortex rings which undergo pairing with a varicose mode. Three-dimensional measurements show the presence...
conference paper 2010
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Percin, M. (author), Hu, Y. (author), Van Oudheusden, B.W. (author), Remes, B. (author), Scarano, F. (author)
The work explores the use of time-resolved tomographic PIV measurements to study a flapping-wing model, the related vortex generation mechanisms and the effect of wing flexibility on the clap-and-fling movement in particular. An experimental setup is designed and realized in a water tank by use of a single wing model and a mirror plate to...
conference paper 2011
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Percin, M. (author), Hu, Y. (author), Van Oudheusden, B.W. (author), Remes, B. (author), Scarano, F. (author)
The work explores the use of time-resolved tomographic PIV measurements to study a flapping-wing model, the related vortex generation mechanisms and the effect of wing flexibility on the clap-and-fling movement in particular. An experimental setup is designed and realized in a water tank by use of a single wing model and a mirror plate to...
conference paper 2011
document
Sciacchitano, A. (author), Dwight, R.P. (author), Scarano, F. (author)
Velocity measurements conducted with particle image velocimetry (PIV) often exhibit regions where the flow motion cannot be evaluated. The principal reasons for this are the absence of seeding particles or limited optical access for illumination or imaging. Additional causes can be laser light reflections and unwanted out-of-focus effects. As a...
conference paper 2012
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Sciacchitano, A. (author), Wieneke, B. (author), Scarano, F. (author)
A super-resolution approach is proposed for the a posteriori uncertainty estimation of PIV measurements. The measured velocity field is employed to determine the displacement of individual particle images. A disparity set is built from the residual distance between paired particle images of successive recordings. Within each interrogation window...
conference paper 2012
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Tuinstra, M. (author), Probsting, S. (author), Scarano, F. (author)
The feasibility of aeroacoustic noise predictions based on Particle Image Velocimetry (PIV) measurements is studied. For this purpose, experiments are conducted on a sharp trailing edge (TE) flow developed along a flat plate at free stream velocity of 15m/s. The acoustic emissions were characterized in the NLR Small Anechoic Wind Tunnel (KAT) by...
conference paper 2013
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Kähler, C.J. (author), Cierpka, C. (author), Scharnowski, S. (author), Manhart, M. (author), Sciacchitano, A. (author), Lynch, K. (author), Scarano, F. (author), Wieneke, B. (author), Willert, C. (author), Jeon, Y. J. (author), Chatellier, L. (author), Augereau, L. (author), Tremblais, B. (author), David, L. (author)
Classical Particle Image Velocimetry (PIV) uses two representations of the particle image distribution to determine the displacement of the particle image pattern by spatial cross-correlation. The accuracy and the robustness are however limited by the fact that only two representations at t and t +?t are present. Thus, only a first order...
conference paper 2013
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Kähler, C.J. (author), Cierpka, C. (author), Scharnowski, S. (author), Manhart, M. (author), Sciacchitano, A. (author), Lynch, K. (author), Scarano, F. (author), Wieneke, B. (author), Willert, C. (author), Jeon, Y. J. (author), Chatellier, L. (author), Augereau, L. (author), Tremblais, B. (author), David, L. (author)
Classical Particle Image Velocimetry (PIV) uses two representations of the particle image distribution to determine the displacement of the particle image pattern by spatial cross-correlation. The accuracy and the robustness are however limited by the fact that only two representations at t and t +?t are present. Thus, only a first order...
conference paper 2013
document
Lynch, K. (author), Scarano, F. (author)
A tomographic PIV system composed of a large number of cameras is used to experimentally investigate the relation between image particle density, number of cameras and the reconstruction quality. The large number of cameras allows to determine an asymptotic behavior for the object reconstruction over a wide range of values for the tracer...
conference paper 2013
document
Lynch, K. (author), Scarano, F. (author)
A tomographic PIV system composed of a large number of cameras is used to experimentally investigate the relation between image particle density, number of cameras and the reconstruction quality. The large number of cameras allows to determine an asymptotic behavior for the object reconstruction over a wide range of values for the tracer...
conference paper 2013
document
Sciacchitano, A. (author), Scarano, F. (author), Wieneke, B. (author)
The topic of uncertainty quantification in particle image velocimetry (PIV) is recognized as very relevant in the experimental fluid mechanics community, especially when dealing with turbulent flows, where PIV plays a prime role as diagnostic tool. The issue is particularly important when PIV is used to assess the validity of results obtained...
conference paper 2013
document
Sciacchitano, A. (author), Scarano, F. (author), Wieneke, B. (author)
The topic of uncertainty quantification in particle image velocimetry (PIV) is recognized as very relevant in the experimental fluid mechanics community, especially when dealing with turbulent flows, where PIV plays a prime role as diagnostic tool. The issue is particularly important when PIV is used to assess the validity of results obtained...
conference paper 2013
document
Violato, D. (author), Ceglia, G. (author), Tuinstra, M. (author), Scarano, F. (author)
This work investigates the three dimensional organization of compressible jets at high-speed regime by tomographic particle image velocimetry (TOMO PIV). Experiments are conducted at Mach numbers 0.3, 0.9 and 1.1 (underexpanded regime) across the end of the potential core within a large cylindrical domain (1.6Dx8D, with D=22mm the jet diameter)....
conference paper 2013
document
Violato, D. (author), Ceglia, G. (author), Tuinstra, M. (author), Scarano, F. (author)
This work investigates the three dimensional organization of compressible jets at high-speed regime by tomographic particle image velocimetry (TOMO PIV). Experiments are conducted at Mach numbers 0.3, 0.9 and 1.1 (underexpanded regime) across the end of the potential core within a large cylindrical domain (1.6Dx8D, with D=22mm the jet diameter)....
conference paper 2013
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Schneiders, J. (author), Dwight, R.P. (author), Scarano, F. (author)
The present work investigates the use of a vortex-in-cell (VIC) inviscid, incompressible Navier-Stokes solver [1,2] to increase temporal resolution of time-resolved 3D fluid-velocity data obtained from tomographic PIV experiments. The measurement rate in such experiments is limited by available laser power, and the requirements of laser pulse...
conference paper 2013
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Pröbsting, S. (author), Serpieri, J. (author), Scarano, F. (author)
Tonal noise generated by airfoils observed at low to moderate Reynolds numbers is related to laminar boundary layer instabilities, which has lead to the term laminar boundary layer instability noise. The particular features of the acoustic spectrum have been discussed and a number of theories have been proposed in literature over the past 50...
conference paper 2013
document
Pröbsting, S. (author), Serpieri, J. (author), Scarano, F. (author)
Tonal noise generated by airfoils observed at low to moderate Reynolds numbers is related to laminar boundary layer instabilities, which has lead to the term laminar boundary layer instability noise. The particular features of the acoustic spectrum have been discussed and a number of theories have been proposed in literature over the past 50...
conference paper 2013
document
Lynch, K. (author), Scarano, F. (author)
A tomographic PIV system is introduced for the instantaneous measurement of the material derivative of velocity (VMD). The system is able to operate with very short temporal separation and is therefore suitable for applications in high-speed flows. The method of operation consists of the imaging of a measurement volume using an array of 12 CCD...
conference paper 2013
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Lynch, K. (author), Scarano, F. (author)
A tomographic PIV system is introduced for the instantaneous measurement of the material derivative of velocity (VMD). The system is able to operate with very short temporal separation and is therefore suitable for applications in high-speed flows. The method of operation consists of the imaging of a measurement volume using an array of 12 CCD...
conference paper 2013
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