A comparative study of flow induced by 1D, 2D and 3D ultrasounds

The acoustic streaming which can facilitate the heat and mass transfer inside liquids is of great importance in ultrasonic processing. Most of previous investigations were mainly focused on the acoustic streaming induced by one dimensional (1D) ultrasound. In this paper, the flow field generated by 1D, 2D and 3D ultrasounds in a cubic box filled with water was investigated by numerical simulations. It is found that the jet flow emitted from the sound source is in the form of cylinder, vortex and wave, for 1D, 2D and 3D ultrasounds, respectively. When the ultrasonic dimension is increased, the flow becomes much stronger in the vicinity of the sound source but little weaker at the box center. By comparing the patterns of the flow generated by the ultrasounds of different dimensions, we demonstrate that 3D ultrasounds not only enhance the overall flow strength, but also effectively promote the uniformity of the flow and enlarge the size of vortices.