A mathematical model of the process of separating suspended microparticles in a dispersed mixture within a 2-branched channel of a microfluidic lab-chip under the influence of an acoustic field has been developed. The model is implemented in the environment of COMSOL Multiphysics, using thermoviscous acoustics, creeping flow, particle tracking in a fluid flow, and fluid-particle interaction multiphysics interfaces. Examples of separation of two types of microparticles suspended in a liquid, which differ in density and size, are shown. The scientific results obtained in this research form the theoretical basis for the development of lab-on-chip designs for separating microparticles suspended in a liquid using an acoustic field, as well as for the fabrication of prototypes of acoustophoretic lab-chips.
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