1
|
Numerical Study of Baroclinic Acoustic Streaming Phenomenon for Various Flow Parameters. ENERGIES 2022. [DOI: 10.3390/en15030854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The article presents a numerical study of the large-amplitude, acoustically-driven streaming flow for different frequencies of the acoustic wave and different temperature gradients between hot and cold surfaces. The geometries studied were mainly two-dimensional rectangular resonators of different lengths, but also one three-dimensional rectangular resonator and one long and narrow channel, representative of a typical U-shaped resistance thermometer. The applied numerical model was based on the Navier–Stokes compressible equations, the ideal gas model, and finite volume discretization. The oscillating wall of the considered geometries was modeled as a dynamically moving boundary of the numerical mesh. The length of the resonators was adjusted to one period of the acoustic wave. The research confirmed that baroclinic acoustic streaming flow was largely independent of frequency, and its intensity increased with the temperature gradient between the hot and cold surface. Interestingly, a slight maximum was observed for some oscillation frequencies. In the case of the long and narrow channel, acoustic streaming manifested itself as a long row of counter-rotating vortices that varied slightly along the channel. 3D calculations showed that a three-dimensional pair of streaming vortices had formed in the resonator. Examination of the flow in selected cross-sections showed that the intensity of streaming gradually decreased as it approached the side walls of the resonator creating a quasi-parabolic profile. The future development of the research will focus on fully 3D calculations and precise identification of the influence of the bounding walls on the streaming flow.
Collapse
|
2
|
Läubli NF, Gerlt MS, Wüthrich A, Lewis RTM, Shamsudhin N, Kutay U, Ahmed D, Dual J, Nelson BJ. Embedded Microbubbles for Acoustic Manipulation of Single Cells and Microfluidic Applications. Anal Chem 2021; 93:9760-9770. [PMID: 34228921 PMCID: PMC8295982 DOI: 10.1021/acs.analchem.1c01209] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/17/2021] [Indexed: 11/29/2022]
Abstract
Acoustically excited microstructures have demonstrated significant potential for small-scale biomedical applications by overcoming major microfluidic limitations. Recently, the application of oscillating microbubbles has demonstrated their superiority over acoustically excited solid structures due to their enhanced acoustic streaming at low input power. However, their limited temporal stability hinders their direct applicability for industrial or clinical purposes. Here, we introduce the embedded microbubble, a novel acoustofluidic design based on the combination of solid structures (poly(dimethylsiloxane)) and microbubbles (air-filled cavity) to combine the benefits of both approaches while minimizing their drawbacks. We investigate the influence of various design parameters and geometrical features through numerical simulations and experimentally evaluate their manipulation capabilities. Finally, we demonstrate the capabilities of our design for microfluidic applications by investigating its mixing performance as well as through the controlled rotational manipulation of individual HeLa cells.
Collapse
Affiliation(s)
- Nino F. Läubli
- Department
of Mechanical and Process Engineering, ETH Zurich, Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
- Molecular
Neuroscience Group, Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, United Kingdom
| | - Michael S. Gerlt
- Department
of Mechanical and Process Engineering, ETH Zurich, Mechanics and Experimental Dynamics, Institute of Mechanical Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Alexander Wüthrich
- Department
of Mechanical and Process Engineering, ETH Zurich, Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Renard T. M. Lewis
- Department
of Biology, ETH Zurich, Institute of Biochemistry, Otto-Stern-Weg 3, 8093 Zurich, Switzerland
| | - Naveen Shamsudhin
- Department
of Mechanical and Process Engineering, ETH Zurich, Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Ulrike Kutay
- Department
of Biology, ETH Zurich, Institute of Biochemistry, Otto-Stern-Weg 3, 8093 Zurich, Switzerland
| | - Daniel Ahmed
- Department
of Mechanical and Process Engineering, ETH Zurich, Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
- Department
of Mechanical and Process Engineering, ETH Zurich, Acoustic Robotics Systems Lab, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Jürg Dual
- Department
of Mechanical and Process Engineering, ETH Zurich, Mechanics and Experimental Dynamics, Institute of Mechanical Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
| | - Bradley J. Nelson
- Department
of Mechanical and Process Engineering, ETH Zurich, Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, Tannenstrasse 3, 8092 Zurich, Switzerland
| |
Collapse
|