Multiphysics simulation of acoustic streaming for microfluidics applications

Acoustic streaming is the steady flow generated by acoustic waves and is widely used in microfluidic devices. Accurate computational modeling of streaming is especially valuable in applications such as pharmaceutical device design. As an inherently multiphysics phenomenon, it is often modeled as a one-way coupling between the acoustic field and the steady flow field. This work demonstrates the use of the finite element method to simulate acoustic streaming with two examples: (1) Eckart streaming driven by focused ultrasound, validated with experimental data, and (2) streaming within a droplet induced by a surface acoustic wave (SAW), involving a piezoelectric substrate and fluid–structure interaction. We also present strategies for solving such complex configurations efficiently.