Piezoelectric micropump using dual-frequency drive

• A piezoelectric micropump using dual-frequency drive is proposed.
• A dual-frequency vibrator is designed by using the two modifying methods we studied.
• A prototype piezoelectric micropump is designed, fabricated and tested.
• Performances of prototype micropump driven by different waves are compared.
• The performances of dual-frequency drive micropump are over 155% improved.

A dual-frequency micropump is proposed and investigated to improve the performance of a piezoelectric micropump for specific application. Through a careful design, the first bending resonant frequency of the vibrator for pumping is one-third of the third bending resonant frequency. When a square wave voltage is used to drive the vibrator, its first and third bending vibration modes are excited. Experimental results show that the maximum flow rate of 163.7 ml/min and a maximum back pressure of 29.7 kPa are obtained when the micropump is driven with a square-wave voltage of 400 Vp-p at 445.5 Hz. Both results are over 155% of those obtained from the single-frequency drive at the same driving voltage swing.