以三棱柱阻流体为无移动部件阀, 结合3D打印技术的快速一体成型特点, 设计并制作了以压电振子为动力源的三棱柱阻流体无阀压电泵。分析了该无阀压电泵的工作原理、理论流量和振子振动特性, 推导出了它的的流量表达式。利用有限元法对三棱柱阻流体的流阻特性进行了仿真模拟, 由其内部压强分布及进出口流速情况, 定性分析了三棱柱阻流体的正反向流阻大小。最后, 使用3D打印机制作了该无阀泵的试验样机, 并进行了流阻和流量测量试验。试验结果表明: 三棱柱阻流体具有正反向绕流流阻不等的特性, 当驱动电压为550 V, 驱动频率为8 Hz时, 该压电泵的输出流量达到最大, 为29.8 mL/min。结果证明了该三棱柱阻流体无阀压电泵具有良好的输送流体的能力。

In combination of the rapid prototyping of 3D printing technology, a valveless piezoelectric pump in the micro-electromechanical system with a triangular prism bluff body was designed and fabricated.For the pump, a piezoelectric vibrator was used as its exciting source and a triangular prism bluff as its valve without moving parts. The working principles, theoretical flow and the vibration characteristics of vibrator were analyzed, and its flow expression was derived. Then, the flow resistance characteristics of triangular prism bluff body was simulated by using finite element method. On the basis of interior pressure distribution and flow speeds in the import and export of the pump, the flow resistances in positive and negative directions were analyzed qualitatively.Finally, an experimental prototype for the valveless piezoelectric pump was fabricated by using a 3D printing machine, and some experiments on flow resistances and flow rates of the pump were measured. The results show that the triangular prism bluff body has different flow resistances in positive and negative directions. The maximum flow rate of the piezoelectric pump obtained is 29.8 ml/min under peak-to-peak voltage of 550 V (8 Hz) . The experimental results validate that the pumping performance of the valveless piezoelectric pump with triangular prism bluff body is excellent.