Searched for: author%3A%22Poelma%2C+C.%22
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van Meerkerk, M. (author), Poelma, C. (author), Hofland, B. (author), Westerweel, J. (author)
We present an experimental study on the gas flow field development over a plunging breaking wave prior to impact on a vertical wall. The variability of wave impact pressure over repeated measurements is well known (Bagnold, 1939). The formation of instabilities on the wave crest are postulated to be the main source of impact pressure variability...
journal article 2022
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Kok, G. (author), Pelevic, N. (author), Chiribiri, A. (author), Milidonis, X. (author), Nazir, M. (author), Capstick, M. (author), Drost, S. (author), Poelma, C. (author), Schaeffter, T. (author)
In the medical sector, various imaging methodologies or modalities (e.g. MRI, PET, CT) are used to assess the health of various parts of the bodies of patients. One such investigation is the blood flow or perfusion of the heart muscle, expressed as the (blood) flow rate normalized by the mass of the volume of interest. Currently there is no...
journal article 2021
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Jahangir, S. (author), Ghahramani, Ebrahim (author), Neuhauser, Magdalena (author), Bourgeois, Sébastien (author), Bensow, Rickard E. (author), Poelma, C. (author)
The objective of this study is to investigate the collapsing behavior of cavitation, which leads to the erosion of material. An experimental examination was conducted in a channel with a semi-circular cylinder obstacle, which serves as a “vortex cavity” generator. Cavitation was achieved by employing a range of pressure differences over the...
journal article 2021
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Hogendoorn, W.J. (author), Chandra, B. (author), Poelma, C. (author)
Particle-laden pipe flows exhibit a gradual laminar-turbulent transition, beyond a critical volume fraction (φ). While classical transition behavior is characterized by the presence of turbulent puffs, this intermittent nature is absent for particle-induced transition. For small pipe-to-particle diameter ratios (D/d) even dilute systems...
journal article 2021
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Dash, A. (author), Hogendoorn, W.J. (author), Poelma, C. (author)
Abstract: We discuss empirical techniques to extract quantitative particle volume fraction profiles in particle-laden flows using an ultrasound transducer. A key step involves probing several uniform suspensions with varying bulk volume fractions from which two key volume fraction dependent calibration parameters are identified: the peak...
journal article 2021
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Poelma, C. (author)
A review is presented of measurement techniques to characterise dispersed multiphase flows, which are not accessible by means of conventional optical techniques. The main issues that limit the accuracy and effectiveness of optical techniques are briefly discussed: cross-talk, a reduced signal-to-noise ratio, and (biased) data drop-out....
review 2020
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Dash, A. (author), Anantharaman, Arjun (author), Poelma, C. (author)
We extend upon the known flow transitions in neutrally buoyant particle-laden Taylor-Couette flows by accessing higher suspension Reynolds numbers in a geometry with radius ratio and aspect ratio. Flow transitions for several particle volume fractions () are investigated by means of flow visualization experiments, in a flow driven by a...
journal article 2020
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Thota Radhakrishnan, A.K. (author), Poelma, C. (author), van Lier, J.B. (author), Clemens, F.H.L.R. (author)
Transition from laminar to turbulent flow of non-Newtonian fluids is investigated using velocimetry data. These data are obtained by applying particle image velocimetry to images obtained through ultrasound imaging (echography). This yielded the observation of intermittent structures (puffs and slugs) that are formed during transition. Post...
journal article 2020
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Milidonis, Xenios (author), Nazir, Muhummad Sohaib (author), Schneider, Torben (author), Capstick, Myles (author), Drost, S. (author), Kok, Gertjan (author), Pelevic, Nikola (author), Poelma, C. (author), Schaeffter, Tobias (author), Chiribiri, Amedeo (author)
Purpose: Cardiovascular magnetic resonance first-pass perfusion for the pixel-wise detection of coronary artery disease is rapidly becoming the clinical standard, yet no widely available method exists for its assessment and validation. This study introduces a novel phantom capable of generating spatially dependent flow values to enable...
journal article 2020
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van Meerkerk, M. (author), Poelma, C. (author), Westerweel, J. (author)
In this work, we extend a planar laser-induced fluorescence method for free surface measurements to a three-dimensional domain using a stereo-camera system, a scanning light sheet, and a modified self-calibration procedure. The stereo-camera set-up enables a versatile measurement domain with self-calibration, improved accuracy, and redundancy...
journal article 2020
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van Eckeveld, A.C. (author), Westerweel, J. (author), Poelma, C. (author)
Severe vibrations and sound production can occur in dry gas flow through corrugated pipes. The addition of very small amounts of liquid to the dry gas flow potentially mitigates these flow-induced vibrations (FIVs) and noise. The different mechanisms behind this whistling mitigation are studied in this work, where acoustic measurements are...
journal article 2020
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van Meerkerk, M. (author), Poelma, C. (author), Hofland, B. (author), Westerweel, J. (author)
We present an experimental study on the variation in wave impact location and present a mechanism for the development of free surface instabilities on the wave crest for repeatable plunging wave impacts on a vertical wall. The existence of free surface instabilities on an impacting wave is well known, but their characteristics and formation...
journal article 2020
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Ghahramani, Ebrahim (author), Jahangir, S. (author), Neuhauser, Magdalena (author), Bourgeois, Sébastien (author), Poelma, C. (author), Bensow, Rickard E. (author)
In this paper, the cavitating flow around a bluff body is studied both experimentally and numerically. The bluff body has a finite length with semi-circular cross section and is mounted on a surface in the throat of a converging-diverging channel. This set-up creates various 3D flow structures around the body, from cavitation inception to...
journal article 2020
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John, Kristine (author), Jahangir, S. (author), Gawandalkar, U.U. (author), Hogendoorn, W.J. (author), Poelma, C. (author), Grundmann, Sven (author), Bruschewski, Martin (author)
This study focuses on the measurement accuracy of Magnetic Resonance Velocimetry (MRV) in high-speed turbulent flows. One of the most prominent errors in MRV is the displacement error, which describes the misregistration of spatial coordinates and velocity components in moving fluids. Displacement errors are particularly critical for experiments...
journal article 2020
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Brunhart, Maxwell (author), Soteriou, Celia (author), Gavaises, Manolis (author), Karathanassis, Ioannis (author), Koukouvinis, Phoevos (author), Jahangir, S. (author), Poelma, C. (author)
Cavitating flow dynamics are investigated in an axisymmetric converging–diverging Venturi nozzle. Computational Fluid Dynamics (CFD) results are compared with those from previous experiments. New analysis performed on the quantitative results from both datasets reveals a coherent trend and shows that the simulations and experiments agree well....
journal article 2020
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Geelhoed, W. J. (author), Damanik, F. F.R. (author), Hamming, J. F. (author), van Agen, M. S. (author), de Boer, H. C. (author), Restrepo, M. Tobón (author), Kislaya, A. (author), Poelma, C. (author), van Zonneveld, A. J. (author)
The durability of prosthetic arteriovenous (AV) grafts for hemodialysis access is low, predominantly due to stenotic lesions in the venous outflow tract and infectious complications. Tissue engineered blood vessels (TEBVs) might offer a tailor-made autologous alternative for prosthetic grafts. We have designed a method in which TEBVs are...
journal article 2020
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Schreier, S. (author), Cornel, W.A. (author), Poelma, C. (author)
The dynamic response of pressure sensors for model tests of sloshing impacts is paramount to recording these highly dynamic events. In this study, we investigated the dynamic behavior of the new pressure sensors presented at ISOPE 2018 (Schreier and Poelma, 2018), which increased the spatial resolution of sloshing pressure measurements by a...
conference paper 2019
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Jahangir, S. (author), Wagner, E.C. (author), Mudde, R.F. (author), Poelma, C. (author)
Cavitation is a complicated multiphase phenomenon, where the production of vapor cavities leads to an opaque flow. Exploring the internal structures of the cavitating flows is one of the most significant challenges in this field of study. While it is not possible to visualize the interior of the cavity with visible light, we use X-ray...
journal article 2019
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Jahangir, S. (author), Ghahramani, Ebrahim (author), Neuhauser, Magdalena (author), Bourgeois, Sébastien (author), Bensow, Rickard E. (author), Poelma, C. (author)
The objective of this study is to investigate the collapsing behavior of cavitation, which leads to erosion. For this purpose, an experimental investigation was performed in a channel with a semi-circular cylinder obstacle at the Hydraulic Laboratory of ANDRITZ HYDRO in Vevey. Cavitation was achieved by employing a range of pressure differences...
conference paper 2019
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Rawat, Digvijay S. (author), Pourquie, M.J.B.M. (author), Poelma, C. (author)
Computational fluid dynamics (CFD) is a powerful method to investigate aneurysms. The primary focus of most investigations has been to compute various hemodynamic parameters to assess the risk posed by an aneurysm. Despite the occurrence of transitional flow in aneurysms, turbulence has not received much attention. In this article, we...
journal article 2019
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