Numerical study of enhanced Rayleigh streaming in resonant cylindrical shells

We have numerically demonstrated a type of enhanced Rayleigh streaming in a resonant cylindrical shell (CS) by using the limiting velocity method. It is found that the main characteristics of the resonant streaming field resemble those of classical Rayleigh streaming in a rigid cylindrical cavity. Nevertheless, the maximum velocity of the demonstrated streaming in the resonant CS is significantly higher than that of classical Rayleigh streaming in a rigid cylindrical cavity under the same acoustic conditions. In addition, the velocity of the demonstrated streaming at the low resonant frequency is higher than that at the high resonant and non-resonant frequencies in the shell. The enhancement of the demonstrated streaming originates from the resonant excitation of non-leaky circumferential modes intrinsic to the CS, characterizing with the enhanced gradient acoustic fields in the viscous boundary layer around its inner surface. This type of streaming may be of interest for acoustofluidic devices in many applications such as particle manipulation and liquid mixing.

Automated summary

Numerical demonstration of enhanced Rayleigh streaming in a resonant cylindrical shell showed similarities with classical Rayleigh streaming in a rigid cavity, but with significantly higher velocity. The enhancement of the streaming originates from resonant excitation of non-leaky circumferential modes intrinsic to the shell, making it potentially useful for applications such as particle manipulation and liquid mixing.