Simultaneous Impacts of Acoustic and Inertial Forces on the Separation of Microparticles

The isolation of microparticles plays a crucial role in various applications, including biological and medical sciences. in this paper, the separation of polystyrene (ps) and polymethyl methacrylate (pmma) particles suspended in water is simulated using the acoustic field and channel geometry. the microchannel consists of two parts, a curve-shaped and a straight part. passive separation occurs in the curve-shaped section due to the flow rotation in the microchannel, and the acoustic force acts and enhances the separation efficiency in the straight part. the acoustic field is created by a pair of aluminum transducers on a piezoelectric substrate. in this study, firstly, the separation of microparticles is done using a microchannel without an acoustic field, leading to a separation efficiency of 81%. the acoustic force is then applied to the microchannel and, the maximum separation efficiency of 94% is obtained. it is observed that the separation efficiency is directly related to the frequency of the acoustic field and inversely related to the inlet flow rate. it should be noted that there is an optimal value for the applied frequency due to the specific value of the channel width. also, the amount of separation efficiency is improved by enhancing the inlet power. it is observed that as the distance between transducers and microchannels is enhanced, the separation efficiency is reduced.