Abstract: Based on the pressure loss coefficient through diffuser/nozzle elements and conservation equation, the analysis model is established for a valveless micropump excited by the piezoelectric actuator. The finite element model of the valveless micropump is built by using the finite element software, and the coupled-field simulation analysis is carried out. The effects of excitation voltage, voltage frequency, pump membrane thickness, piezoelectric membrane thickness and piezoelectric material on the pump performance are simulated and analyzed under different boundary conditions. The results show the valveless micropump has good flow rectification, and its output characteristics increase with the increase of the excitation voltage. There is an optimal piezoelectric membrane thickness for the largest flow under the partly clamped boundary condition and the electric-field strength of 500 V/mm. These results are helpful to designing the optimal valveless micropump.

Key words: Numerical simulation, Piezoelectric actuation, Structure optimization, Valveless micropump