Searched for: subject:"piv"
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Duinmeijer, S.P.A. (author)
This is an experimental and theoretical research on the motion of buoyant particles in the flow of a free-surface vortex at moderate to high particle Reynolds numbers.
doctoral thesis 2020
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Voorneveld, J.D. (author), Saaid, H. (author), Schinkel, C.V. (author), Radeljic, Nikola (author), Lippe, Boris (author), Gijsen, F.J.H. (author), van der Steen, A.F.W. (author), de Jong, N. (author), Claessens, T.P.T. (author), Vos, H.J. (author), Kenjeres, S. (author), Bosch, J.W. (author)
Left ventricular (LV) blood flow is an inherently complex time-varying 3-D phenomenon, where 2-D quantification often ignores the effect of out-of-plane motion. In this study, we describe high frame rate 4-D echocardiographic particle image velocimetry (echo-PIV) using a prototype matrix transesophageal transducer and a dynamic LV phantom for...
journal article 2020
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Scharnowski, S. (author), Sciacchitano, A. (author), Kahler, Christian J. (author)
For the reliable estimation of velocity vector fields by means of particle image velocimetry (PIV), the cross-correlation functions calculated from the signal within each interrogation window must feature a distinct peak that represents the average shift of the particle image ensemble. A high valid detection probability (VDP) of the correct...
journal article 2019
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Dulin, V. M. (author), Lobasov, A. S. (author), Chikishev, L. M. (author), Markovich, D. M. (author), Hanjalic, K. (author)
We report on a study of the impact of coherent helical vortex structures on the shape of the reaction zone and heat release in swirling methane/air flames in regimes with a vortex breakdown. Three kinds of atmospheric flames are considered, viz., fuel-lean and fuel-rich premixed flames and a partially premixed fuel-rich lifted flame. Based on...
journal article 2019
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Guo, Y. (author), Markine, V.L. (author), Zhang, X. (author), Qiang, Weile (author), Jing, Guoquig (author)
The performance and deformation of ballast bed are significantly influenced by the particle morphology (size and shape), the rheology (translation and rotation), and the degradation (breakage and abrasion). Regarding the ballast particle morphology, the ballast particle size is generally measured by sieving and described with the Particle Size...
review 2019
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Haidari, A.H. (author), Heijman, S.G.J. (author), Uijttewaal, W.S.J. (author), van der Meer, W.G.J. (author)
Feed spacer orientation affects the velocity pattern and pressure drop of spacer-filled channels such as those encountered in Spiral-wound Membrane (SWM) modules of Reverse Osmosis (RO). However, there are only limited numbers of experimental studies on this topic. This study sets out to reveal more detailed information on the pressure drop...
journal article 2019
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Adam, Florian (author), Terra, W. (author), Sciacchitano, A. (author)
Large-scale particle image velocimetry (PIV) is used to characterize the dynamics of the unsteady wake of a non-pedalling full-scale cyclist. This to provide better understanding of the flow structures that generate the aerodynamic drag. Instantaneous flow fields are acquired and averaged to obtain the time-average flow topology. Afterwards,...
journal article 2019
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Casacuberta, J. (author), Groot, K.J. (author), Ye, Q. (author), Hickel, S. (author)
Micro-ramps are popular passive flow control devices which can delay flow separation by re-energising the lower portion of the boundary layer. We compute the laminar base flow, the instantaneous transitional flow, and the mean flow around a micro-ramp immersed in a quasi-incompressible boundary layer at supercritical roughness Reynolds number...
journal article 2019
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Timoshevskiy, Mikhail V. (author), Pervunin, Konstantin S. (author), Markovich, Dmitriy M. (author), Hanjalic, K. (author)
We studied cavitating flow over the suction side of a symmetric 2D foil - a scaled-down model of high-pressure hydroturbine guide vanes (GV) - in different cavitation regimes at several attack angles. High-speed imaging was used to analyze spatial patterns and time dynamics of the gas-vapor cavities, as well as for evaluating the...
conference paper 2019
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Saaid, Hicham (author), Voorneveld, Jason (author), Schinkel, C.V. (author), Westenberg, Jos (author), Gijsen, F.J.H. (author), Segers, Patrick (author), Verdonck, Pascal (author), de Jong, N. (author), Kenjeres, S. (author)
Left ventricular flow is intrinsically complex, three-dimensional and unsteady. Its features are susceptible to cardiovascular pathology and treatment, in particular to surgical interventions involving the valves (mitral valve replacement). To improve our understanding of intraventricular fluid mechanics and the impact of various types of...
journal article 2019
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van Gent, P.L. (author)
Pressure reconstruction based on particle image velocimetry (PIV) refers to the determination of pressure data from pictures of small tracer particles added to a flow. The technique possesses a unique combination of beneficial characteristics in that it non-intrusively provides simultaneous pressure and velocity data in the flow field without...
doctoral thesis 2018
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Haidari, A.H. (author), Heijman, S.G.J. (author), van der Meer, W.G.J. (author)
Making improvements to feed spacers of spiral-wound membrane (SWM) modules of reverse osmosis (RO) is a necessary step towards a wider application of these modules. This study sets out to evaluate the performance of six commercial feed spacers by comparing their actual velocity profiles and their pressure drop. Velocity profiles are obtained...
journal article 2018
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Zhang, Xueqing (author), Sciacchitano, A. (author), Pröbsting, S. (author)
Particle image velocimetry for the experimental assessment of trailing edge noise sources has become focus of research in recent years. The present study investigates the feasibility of the noise prediction for high-lift devices based on time-resolved particle image velocimetry (PIV). The model under investigation is a NACA 0015 airfoil with...
journal article 2018
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Schneiders, J.F.G. (author), Scarano, F. (author), Jux, C. (author), Sciacchitano, A. (author)
This study describes the working principles of the coaxial volumetric velocimeter (CVV) for wind tunnel measurements. The measurement system is derived from the concept of tomographic PIV in combination with recent developments of Lagrangian particle tracking. The main characteristic of the CVV is its small tomographic aperture and the...
journal article 2018
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Caridi, G.A.P. (author)
A new type of tracer is making its entry in the scenario of wind-tunnel measurements: helium-filled soap bubbles (HFSB). The present work discusses the main fluid-dynamic and optical properties of HFSB to evaluate their use for quantitative measurements in aerodynamic experiments.<br/>In the past three decades, particle image velocimetry (PIV)...
doctoral thesis 2018
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van Gent, P.L. (author), van Oudheusden, B.W. (author), Schrijer, F.F.J. (author)
The feasibility of computing the flow pressure on the basis of PIV velocity data has been demonstrated abundantly for low-speed conditions. The added complications occurring for high-speed compressible flows have, however, so far proved to be largely inhibitive for the accurate experimental determination of instantaneous pressure. Obtaining...
journal article 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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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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Gotfredsen, Erik (author), Kunoy, Jens D. (author), Mayer, Stefan (author), Poelma, C. (author), Westerweel, J. (author), Meyer, Knud Erik (author)
The effect of pulsations in a catalyst converter is investigated with the aim of determining if a steady flow captures the same physical phenomena as the pulsating flow. For this specific case, guide vanes are mounted in the sudden expansion to obtain a uniform inlet flow to the catalytic layers. The test rig is successfully validated against...
conference paper 2018
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Eisma, H.E. (author), Tam, D.S.W. (author), Westerweel, J. (author), van de Water, W. (author)
We present results on the analysis of measurements on the dispersion of a contaminant in a turbulent boundary layer. The contaminant is a fluorescent dye (Rh.-B) that was introduced in a turbulent boundary layer (푅푅푒푒# = 3050) in a water channel. The velocity field was measured by means of tomographic PIV. Simultaneously, the concentration field...
conference paper 2018
Searched for: subject:"piv"
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