中文摘要：

设计了一套压电双晶片作为激励源的半球缺阻流体无阀压电泵。分析了该压电泵的结构及工作原理，并采用有限元软件对其内部流场进行模拟分析。仿真结果表明：该泵存在正反向流阻不等特性，半球缺阻可以作为泵的无运动部件阀。最后，实际制作了半球缺无阀压电样泵和多组半径不等的半球缺，并进行了泵的流阻及流量实验。实验结果表明：该泵正反向流时间差随入口压强增大而减小；当驱动电压为150V，频率为17Hz，半球缺半径为4．0mm时，泵的输出流量达到最大，其值为121．4ml／min；同时，该泵单位时间内的输出流量随半球缺半径增大而呈递减的变化趋势，而且半球缺的半径大小对该类无阀压电泵的工作效能有较大的影响。

英文摘要：

A valve-less piezoelectric pump with a Hemisphere-segment Bluff-body（HSBB） was de- signed by using a piezoelectric bimorph as exciting source. The structure and working principle of the piezoelectric pump were analyzed theoretically, then the finite element software was employed in sim- ulating the flow fields of the pump. The theoretical analysis show that the positive and negative flow resistances of the pump are unequal, so the HSBBs can be used as no-moving parts in the pump. Fi- nally, a sample pump based on the HSBB was fabricated and a series of HSBBs with different radiuses were produced. Some experiments on flow resistances and output flow rates of the pump were per- formed. The experiment results indicate that the time difference between the positive and negative flows decreases with increasing the pressure difference. The maximum flow rate of the pump obtained is 121.4 ml/min under a operating frequency of 15＇ Hz and the HSBB＇s radius of 4.0 mm. Moreover, the experiments give a relationship that the flow rate of the pump increases with the decreasing size of HSBB＇s radius during the unit time under keeping the peak-to-peak voltage of 150 V, which has a greater influence on the working efficiency of the pump.