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arXiv · 2103.10192

Fast microscale acoustic streaming driven by a temperature-gradient-induced non-dissipative acoustic body force

Wei Qiu·Jonas Helboe Joergensen·Enrico Corato·Henrik Bruus·Per Augustsson
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Abstract

We study acoustic streaming in liquids driven by a non-dissipative acoustic body force created by light-induced temperature gradients. This thermoacoustic streaming produces a velocity amplitude approximately 50 times higher than boundary-driven Rayleigh streaming and 90 times higher than Rayleigh-Benard convection at a temperature gradient of 10 K/mm in the channel. Further, Rayleigh streaming is altered by the acoustic body force at a temperature gradient of only 0.5 K/mm. The thermoacoustic streaming allows for modular flow control and enhanced heat transfer at the microscale. Our study provides the groundwork for studying microscale acoustic streaming coupled with temperature fields.

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Wei Qiu, Jonas Helboe Joergensen, Enrico Corato, Henrik Bruus, Per Augustsson. 2021-03-18. Fast microscale acoustic streaming driven by a temperature-gradient-induced non-dissipative acoustic body force. https://doi.org/10.1103/physrevlett.127.064501

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