Design, modelling and simulation of a PZN-PT actuated micropump

摘要

We present an optimization methodology for the design of a self-priming piezoelectrically actuated pump made of a Pyrex wafer bonded to silicon. This methodology maximizes volumetric displacement of the actuating membrane and consequently the maximum flow rate performance. It is shown that maximum membrane deflection does not necessarily equal maximum volumetric displacement, thus a pump can be better optimized for maximum flow rate by maximizing the stroke volume rather than the maximum membrane deflection. The use of a novel piezoelectric material, a PZN-PT crystal, is proposed for the actuation of the pump membrane instead of the more commonly used PZT-5H. The importance of the geometry and relative size of the elements in the membrane/actuator system is investigated by means of finite elements analysis, demonstrating that a square membrane with circular actuator at a radius ratio of 0.9 emerges as the optimal design.