The acoustic streaming effects of sonic black hole

In this paper, the acoustic streaming effects of Sonic Black Hole (SBH) are deeply studied by using the numerical and simulation method. By solving Navier-Stokes equations of compressible fluid, we analyze the flow characteristics of acoustic medium in SBH excited by sound wave, and further discuss the acoustic streaming effects and sound wave capture mechanism of SBH. The phenomenon of simultaneous reduction of medium and high-frequency sound reflection and transmission is analyzed. Under the excitation of medium- and high-frequency sound waves, the interaction between fluid medium flow and SBH structure leads to the uneven internal velocity distribution in the sound propagation direction, which can lead to the phenomenon of sound wave capture and deceleration. For low-frequency sound waves, the velocity distribution of sound medium is uniform, and there is almost no change in velocity gradient, resulting in the uniform distribution of sound pressure without sound absorption. These theoretical and numerical results are in good agreement with the experimental results in the literature, and also verify our results. Finally, by improving the structure, increasing the complexity of sound medium flow and the gradient change in the direction of sound propagation, the sound absorption and insulation ability of the SBH can be further improved. This study reveals the sound transmission mechanism of SBH, which can provide a new idea for the suppression of low-frequency sound waves in SBH.

Automated summary

This paper deeply studies the acoustic streaming effects of Sonic Black Hole (SBH) through numerical and simulation methods. The flow characteristics of the acoustic medium in SBH excited by sound waves are analyzed, and the acoustic streaming effects and sound wave capture mechanism of SBH are discussed. The results show that for low-frequency sound waves, there is almost no interaction with the fluid medium flow, resulting in a uniform distribution of sound pressure. However, under the excitation of medium- and high-frequency sound waves, the interaction between the fluid medium flow and SBH structure leads to an uneven internal velocity distribution, resulting in sound wave deceleration and capture. By improving the SBH structure and increasing the complexity of the flow, the sound absorption and insulation ability of SBH can be further improved.