Study on SAW Streaming and its Application to Fluid Devices

Shiokawa, Showko; Matsui, Yoshikazu; Ueda, Toshihiko

doi:10.7567/jjaps.29s1.137

Cited by 80 publications

(56 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An upper bound for the effective body force invoked by gradients in the sound field along the SAW propagation axis in the fluid [12] can be determined from an upper bound for the rate of sound attenuation along the film. We estimate this upper bound for the sound attenuation rate by neglecting reflections of sound off the free surface of the film, so that the sound field in (4.2) is attenuated strictly owing to the SAW attenuation, a common approach [13], because its attenuation length (measured in millimetres for most fluids) is three orders of magnitude smaller than the attenuation length of sound in the film (in the range of metres) [14].…”

Section: Critical Transition Thickness H C 2 Between Thick and Intermmentioning

confidence: 99%

Double flow reversal in thin liquid films driven by megahertz-order surface vibration

et al. 2014

View full text Add to dashboard Cite

Arising from an interplay between capillary, acoustic and intermolecular forces, surface acoustic waves (SAWs) are observed to drive a unique and curious double flow reversal in the spreading of thin films. With a thickness at or less than the submicrometre viscous penetration depth, the film is seen to advance along the SAW propagation direction, and self-similarly over time t 1/4 in the inertial limit. At intermediate film thicknesses, beyond one-fourth the sound wavelength λ in the liquid, the spreading direction reverses, and the film propagates against the direction of the SAW propagation. The film reverses yet again, once its depth is further increased beyond one SAW wavelength. An unstable thickness region, between λ /8 and λ /4, exists from which regions of the film either rapidly grow in thickness to exceed λ /4 and move against the SAW propagation, consistent with the intermediate thickness films, whereas other regions decrease in thickness below λ /8 to conserve mass and move along the SAW propagation direction, consistent with the thin submicrometre films.

show abstract

Section: Critical Transition Thickness H C 2 Between Thick and Intermmentioning

confidence: 99%

Double flow reversal in thin liquid films driven by megahertz-order surface vibration

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The window for jetting is indeed narrow, between the effects of less power in simply moving the drop and the effects of more power that tend to atomize the drop. Shiokawa et al (1990) reported the phenomenon many years ago, and there it remained something of a curiosity until some additional work was done to understand the nature of the jet formation and to consider the behavior of the fluid from a microfluidics perspective, as taken by and shown in Fig. 14.…”

Section: Jetting and Levitationmentioning

confidence: 99%

Microscale acoustofluidics: Microfluidics driven via acoustics and ultrasonics

2011

View full text Add to dashboard Cite

This article reviews acoustic microfluidics: the use of acoustic fields, principally ultrasonics, for application in microfluidics. Although acoustics is a classical field, its promising, and indeed perplexing, capabilities in powerfully manipulating both fluids and particles within those fluids on the microscale to nanoscale has revived interest in it. The bewildering state of the literature and ample jargon from decades of research is reorganized and presented in the context of models derived from first principles. This hopefully will make the area accessible for researchers with experience in materials science, fluid mechanics, or dynamics. The abundance of interesting phenomena arising from nonlinear interactions in ultrasound that easily appear at these small scales is considered, especially in surface acoustic wave devices that are simple to fabricate with planar lithography techniques common in microfluidics, along with the many applications in microfluidics and nanofluidics that appear through the literature.

show abstract

“…More recently, acoustic streaming is the subject of a burst of interest with the development of microfluidic applications [7,8]. For instance, it is at the core of the physics involved in droplets actuation with Surface Acoustic Waves (SAW) [9] for lab-on-a-chip facilities, providing a versatile tool for droplet displacement [10][11][12], atomization [13], jetting [14,15] or vibration [12,16,17]. Moreover, vorticity associated with acoustic streaming is the main envisioned phenomenon to ensure efficient mixing of liquids [18,19].…”

Section: Introductionmentioning

confidence: 99%

Cyclones and attractive streaming generated by acoustical vortices

et al. 2014

View full text Add to dashboard Cite

Acoustical and optical vortices have attracted large interest due to their ability in capturing and manipulating particles with the use of the radiation pressure. Here we show that acoustical vortices can also induce axial vortical flow reminiscent of cyclones whose topology can be controlled by adjusting the properties of the acoustical beam. In confined geometry, the phase singularity enables generating "attractive streaming" with a flow directed toward the sound source. This opens perspectives for contact-less vortical flow control.

show abstract

Study on SAW Streaming and its Application to Fluid Devices

Cited by 80 publications

References 0 publications

Double flow reversal in thin liquid films driven by megahertz-order surface vibration

Double flow reversal in thin liquid films driven by megahertz-order surface vibration

Microscale acoustofluidics: Microfluidics driven via acoustics and ultrasonics

Cyclones and attractive streaming generated by acoustical vortices

Contact Info

Product

Resources

About