Searched for: subject%3A%22cavitating%22
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Zhu, P. (author), Simón Grau, I. (author), Kokalari, I. (author), Kohane, Daniel S. (author), Rwei, A.Y. (author)
Ultrasound is a promising technology to address challenges in drug delivery, including limited drug penetration across physiological barriers and ineffective targeting. Here we provide an overview of the significant advances made in recent years in overcoming technical and pharmacological barriers using ultrasound-assisted drug delivery to...
review 2024
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Nanda, S. (author)
The research presented in this thesis aims at understanding how gases influence the cavitating vortex generated by a wing tip in a stationary flow. Gases in the flow occur as non-condensible microbubbles as well as gases dissolved in the liquid. They are typically abundant in surface flows. For studying how dissolved gases influence a cavitating...
doctoral thesis 2023
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Melissaris, Themistoklis (author)
Cavitation is the formation of vapor pockets in a liquid due to a pressure drop or an increase in speed. Cavitation nuisance can be disastrous for mechanical components, and therefore needs to be controlled from an early design stage. However, predicting cavitation dynamics using CFD (Computational Fluid Dynamics) and therefore the performance...
doctoral thesis 2023
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Nagalingam, Nagaraj (author), Raghunathan, Aswin (author), Korede, V.B. (author), Overmars, E.F.J. (author), Hung, S. (author), Hartkamp, Remco (author), Padding, J.T. (author), Smith, C.S. (author), Eral, H.B. (author)
Optofluidic devices have revolutionized the manipulation and transportation of fluid at smaller length scales ranging from micrometers to millimeters. We describe a dedicated optical setup for studying laser-induced cavitation inside a microchannel. In a typical experiment, we use a tightly focused laser beam to locally evaporate the solution...
journal article 2023
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Li, H. (author), Li, X. (author), Collado Lara, G. (author), Lattwein, K.R. (author), Mastik, Frits (author), Beurskens, Robert (author), van der Steen, A.F.W. (author), Verweij, M.A. (author), de Jong, N. (author), Kooiman, Klazina (author)
Ultrasound contrast-mediated medical imaging and therapy both rely on the dynamics of micron- and nanometer-sized ultrasound cavitation nuclei, such as phospholipid-coated microbubbles and phase-change droplets. Ultrasound cavitation nuclei respond non-linearly to ultrasound on a nanosecond time scale that necessitates the use of ultra-high...
journal article 2023
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Kalikatzarakis, Miltiadis (author), Coraddu, A. (author), Atlar, Mehmet (author), Gaggero, Stefano (author), Tani, Giorgio (author), Oneto, Luca (author)
For propeller-driven vessels, cavitation is the most dominant noise source producing both structure-borne and radiated noise impacting wildlife, passenger comfort, and underwater warfare. Physically plausible and accurate predictions of the underwater radiated noise at design stage, i.e., for previously untested geometries and operating...
journal article 2023
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Melissaris, Themistoklis (author), Schenke, S. (author), Bulten, Norbert (author), van Terwisga, T.J.C. (author)
Propeller cavitation erosion prediction at an early design stage is becoming more and more important since it is one of the key constraints in the search for maximum propeller efficiency. Despite the experience from model tests, cavitation erosion research on actual ship scale is very limited. In this study, an attempt is made to assess the...
journal article 2022
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Fujikawa, Toshihide (author), Egashira, R. (author), Hooman, K. (author), Yaguchi, H. (author), Masubuchi, H. (author), Fujikawa, S. (author)
Theory of dynamical cavitation threshold for vapor and non-condensable gas bubble nuclei is proposed based on a model equation constructed from Rayleigh-Plesset equation for glycerol, the liquid with viscosity higher than that of water by 1500 times, under a finite duration of strong tension. The model equation is ascertained to be valid in...
journal article 2022
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Nanda, S. (author), Westerweel, J. (author), van Terwisga, T.J.C. (author), Elsinga, G.E. (author)
Following their inception, vortex cavities emanating from stationary wing tips in cavitation tunnels are often observed to grow. These effects are usually attributed to the free and dissolved non-condensable gases in the liquid. However, a detailed mechanism for the cavity's growth is not known. Consequently, the repeatability of vortex...
journal article 2022
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Kalikatzarakis, Miltiadis (author), Coraddu, A. (author), Atlar, Mehmet (author), Gaggero, Stefano (author), Tani, Giorgio (author), Villa, Diego (author), Oneto, Luca (author)
The potential impact of underwater radiated noise from maritime operations on marine fauna has become an important issue. The most dominant noise source on a propeller-driven vessel is propeller cavitation, producing both structure-borne and radiated noise, with a broad spectrum that covers a wide range of frequencies. To ensure acceptable...
journal article 2022
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Klapwijk, M.D. (author)
There is increasing attention for the effects of anthropogenic underwater radiated noise (URN) on marine fauna. This is expected to lead to regulations with respect to the maximum permitted sound emissions of ships. It is known that cavitating tip vortices, generated by ship propellers, are some of the key contributors to URN. Consequently,...
doctoral thesis 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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Klapwijk, M.D. (author), Lloyd, T. (author), Vaz, G. (author), van Terwisga, T.J.C. (author)
The Delft Twist 11 Hydrofoil is a common test case for investigating the interaction between turbulence and cavitation modelling in computational fluid dynamics. Despite repeated investigations, results reported for the lift and drag coefficient are accompanied by significant uncertainties, both in experimental and numerical studies. When...
journal article 2021
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Schenke, S. (author)
Cavitation erosion is a problem in the design of a wide range of fluid machinery involving liquid flows. Ship propellers, rudders, hydro pumps and turbines or diesel injectors are some of the most prominent examples. Cavitation occurs at locations of high local flow velocity, where the pressure may drop so low that the liquid phase vaporizes....
doctoral thesis 2020
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Jahangir, S. (author)
Cavitation is a well-known phenomenon, occurring in a wide range of applications. In most applications, cavitation is undesirable, such as turbines, pumps, ship propellers and diesel injector nozzles. Cavitation can cause material erosion, flow blockage, noise and degradation of equipment over time. The ability to predict the behavior of this...
doctoral thesis 2020
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Kooiman, Klazina (author), Roovers, Silke (author), Langeveld, Simone A.G. (author), Kleven, Robert T. (author), Dewitte, Heleen (author), O'Reilly, Meaghan A. (author), Escoffre, Jean Michel (author), Bouakaz, Ayache (author), Verweij, M.D. (author)
Therapeutic ultrasound strategies that harness the mechanical activity of cavitation nuclei for beneficial tissue bio-effects are actively under development. The mechanical oscillations of circulating microbubbles, the most widely investigated cavitation nuclei, which may also encapsulate or shield a therapeutic agent in the bloodstream,...
review 2020
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Codrignani, A. (author), Savio, D. (author), Pastewka, L. (author), Frohnapfel, B. (author), van Ostayen, R.A.J. (author)
In this work we assess the applicability of the adjoint optimization technique for determining optimal surface topographies of two surfaces in relative motion in presence of a thin lubricant films that can cavitate. Among the existing numerical tools for topology optimization in engineering problems, the adjoint method represents a promising...
journal article 2020
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Melissaris, Themistoklis (author), Schenke, S. (author), Bulten, Norbert (author), van Terwisga, T.J.C. (author)
Predicting the cavitation impact loads on a propeller surface using numerical tools is becoming essential, as the demand for more efficient designs, stretched to the limit, is increasing. One of the possible design limits is governed by cavitation erosion. The accuracy of estimating such loads, using a URANS approach, has been investigated....
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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Saint-Michel, B.F.B. (author), Garbin, V. (author)
Bubbles in complex fluids are often desirable, and sometimes simply inevitable, in the processing of formulated products. Bubbles can rise by buoyancy, grow or dissolve by mass transfer, and readily respond to changes in pressure, thereby applying a deformation to the surrounding complex fluid. The deformation field around a stationary,...
review 2020
Searched for: subject%3A%22cavitating%22
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