Research on driving the MEMS ultrasonic separator based on two-dimensional normal mode

To improve the efficiency of a separator based on the two-dimensional normal mode, a driving model has been proposed in this paper. Firstly, two main problems influencing the efficiency of separation are discussed. Secondly, according to the structural characteristics of the separator, a model of double-sound sources with anti-phases to drive (1, 1) normal mode in the separator is proposed, and other normal modes of which frequencies are near to (1, 1) normal mode are avoided. And to solve the problem of the shortage of acoustic radiation force caused by fixed operation mode of the separator, frequency sweep technique is employed. Finally, the driving model and frequency sweep technique have shown advantages to improve the separating efficiency in the experiments.