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Microstreaming of acoustically excited bubbles presents great potential to mitigate fouling for membrane technologies. However, the acoustic streaming in bulk fluids under membrane separation conditions is not well explored. In this work, we investigate the microstreaming of 3D printed Helmholtz-like bubble-trapping structures (BTSs) under no flow, pressurized, and crossflow conditions that are relevant to membrane applications. Trapped bubbles are shown to generate formidable microstreaming that spans millimeter distances with velocity as high as 125 mm/s in a bulk aqueous medium. However, complex mode shapes of the bubble oscillation and bubble growth were observed during the frequency sweep. As a result, the streaming velocity decreases by 76% over 30 min, under single frequency excitation. The BTS displayed effective microstreaming under hydrostatic pressure up to 9.0 kPa, and under a crossflow velocity up to 0.2 mm/s, where the microstreaming zone reduced to <1 mm. The results provide the operation window, as well as challenges, for future integration of the BTS into bulk membrane separation processes.
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Microfluidic viscometer by acoustic streaming transducers
We introduce μVAST, a high-throughput acoustic microstreaming platform using second-order microstreaming to induce fluid transport and measure the viscosity of 16 samples, automating process flows in drug development, materials manufacturing and production.
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- PAR ID:
- 10490315
- Editor(s):
- Wheeler, A.
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Lab on a Chip
- Volume:
- 23
- Issue:
- 11
- ISSN:
- 1473-0197
- Page Range / eLocation ID:
- 2577 to 2585
- Subject(s) / Keyword(s):
- microfluidics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d3lc00101f
