Surface Acoustic Wave Driven Effects in Microfluidics
* Presenting author
Abstract:
The use of surface acoustic wave (SAW) underpins promising possibilities for a versatile, yet non-contact manipulation of particles and cells in a microfluidic system. Despite their increasing significance, the physical phenomena underlying SAW-driven systems are yet to be fully elucidated. The combination of experimental characterization and numerical simulation can provide a better understanding of the fundamental mechanisms arisen upon incidence of a propagating SAW within a microchannel-enclosed fluid. Considering the influence of acoustic diffraction, we identify five general distinct mechanisms within an individual system. These cause spatially periodic patterning of particles (i) orthogonal and (ii) parallel to the SAW-propagation direction, fluid swirling in two orthogonal planes (iii) within the extent of the SAW beam, here termed lobe streaming, and (iv) at the peripheral region of the SAW beam, here termed peripheral streaming, and finally, (v) unidirectional translation of particles along the SAW-propagation direction, the most reported effect in such systems (1). The dominance of these mechanisms, however, depends on the particles’ size and their spatial location in the channel. REFERENCE: [1] Fakhfouri, A, et al. (2018) Lab Chip 18 (15), 2214 - 2224.