Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 10 of 10 for “"Steady streaming"”.
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The harmonic excitation of a cylindrical bubble pinned to a plane surface: flow field and oscillation dynamics
… and subsequently describe the resulting steady flow that results in the fluid in the exterior of such a bubble. We first derive an analytical expression for the allowable shape oscillations of a two-dimensional bubble pinned to a wall, in the limit of a thin oscillatory boundary layer, …
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Microbubble streaming flows for non-invasive particle manipulation and liquid mixing
… an emerging actuating mechanism -- microbubble steady streaming flows -- by emphasizing both fundamental understanding and the design and applications of bubble-based microfluidic devices. Under periodic acoustical driving, microbubbles with radius 20 -- 100µm absorbed or attached to a solid …
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Quantifying particle sorting in microbubble streaming flows
… behaviour of microparticles in a bubble streaming flow. We show that in microchannels, the steady streaming flow generated by an ultrasonically driven semicylindrical microbubble can be combined with a Poiseuille flow to achieve tunable, high throughput, size-sensitive sorting and …
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A numerical study on microbubble mixer
… on the micromixer, a device which actuates steady streaming by semi-cylindrical sessile bubble oscillations. The mixer's capability of producing chaotic mixing is confirmed and a numerical simulation that is in good agreement with the experiment is developed, which then leads to the …
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Velocity and temperature fields in oscillating boundary layers
… are studied for laminar flows. In general the steady-streaming contributions are small, but it appears from the present results that for large Eckert numbers the wall heat transfer may be altered up to 40% by the streaming phenomena. Unfortunately there is no experimental data on this subject. …
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Unsteady boundary layers and separation
… properties of boundary layer and separation in unsteady flow, play a very important role in fluid and structural mechanics because of their drastic effect on control forces generated by aerodynamic surfaces and loads carried by aerodynamic structures. Prandtl's criterion for separation has been …
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Particle manipulation by attractive and repulsive forces in 2-D streaming flows
… by the superposition of microbubble streaming and transport flows. Our experimental setup uses steady streaming flow generated by ultrasonically driven semi-cylindrical microbubble combined with Poiseuille flow. Previous experiments have shown instances of particles being repelled …
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Generation of sand ripples and sand bars by surface waves
… conditions. It is found that the wave-induced steady streaming has no effect on ripple growth. Thus, ripple instability is locally similar to the cases for oscillatory flows and for purely progressive waves, and is driven by ripple-induced flow. But the intensity of this process varies …
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Quantifying microbubble streaming and its applications
… then become rectified into strong secondary steady currents in the fluid, termed ``streaming''. While several researchers have used such setups in experiments, a theoretical quantification of the bubble streaming flows, crucial for the systematic design of practical microfluidics …
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Acoustofluidic Innovations for Cellular Processing On-Chip
… a combination of microfluidic weirs and acoustic streaming vortices to first trap single cells in specific locations of a microfluidic device, and then transfer the cells into adjacent low shear compartments with an acoustic switch. This highly adaptable, compact system allows for imaging with …