Valveless acoustic standing wave micropump for biomedical applications: a numerical study

The operation principle of the valveless acoustic standing wave micropump is described. Time-variant flow structures through the planar diffuser-nozzle element of this micropump for different values of the divergence angle of the diffuser-nozzle element at excitation frequency of f = 20 kHz are numerically investigated. The variations of micropump flow rate, pressure loss coefficients of the nozzle and diffuser, and diffuser efficiency are shown as functions of theta. The higher micropump flow rate is found to be achieved at larger values of theta. However, increasing theta from 45. to 60. shows no significant increase in the net flow rate. The results also show that the maximum diffuser efficiency is achieved at theta = 45.