A Valve-less PZT Micropump with Isosceles Triangle Cross-section Diffuser Elements

A valve-less micropump with isosceles triangle cross-section nozzle-diffuser elements driven by PZT (Pb(Zr,Ti)O₃) patch had been successfully fabricated by MEMS (mciro-electromechanical system) technologies. As flow rectifying elements, the nozzle-diffuser is in substitute of active check valve. Although the volume flow rate characteristics of conical, pyramidal, and flat-wall nozzle-diffuser have been discussed, the isosceles triangle cross-section nozzle-diffuser elements have not been reported. The design and fabrication processes were demonstrated and volume flow rate as a function of an applied voltage were presented by experiment. The volume flow rate of micropump increased linearly with increasing the voltage applied. The numeration result of computer volume flow rate varied with pressure drop and the volume flow rate varied with pressure loss coefficients was also given. The maximum volume flow rate is 12.2muL/min and the backpressure is 578Pa when applying a 250V square driving voltage at 8000 Hz