压电振子对压电泵极限输出压力的影响

Effect of Piezoelectric Actuators on Ultimate Pressure of Piezo-Pump

为了解决压电泵设计中极限压力计算及压电振子的选用问题,提出了一种在恒定电压下通过压电振子参数计算压电泵极限输出压力的方法。在弹性小变形的基础上,应用弹性力学板壳理论的相关内容,通过振子变形量相等引入等效集中力及振子出力系数概念对压电振子的输出力特性进行研究,得出了等效集中力和压电泵极限输出压力关于压电振子参数的解析表达式。使用Matlab在各参数的常用范围内对模型进行了计算,分析了压电振子各个参数对极限输出压力的影响方式及取值范围。分析及实验结果表明:胶水的弹性模量及各层材料的泊松比对总体性能影响较小,在振子设计中不做考虑;基板厚度在0.8mm以下时,输出压力随其厚度增加而线性增加;在基板厚度大于0.4mm、陶瓷厚度小于0.3mm的条件下,陶瓷厚度降低输出压力增加现象最为明显,并且计算数值解与实验结果吻合。

To solve the calculation of ultimate pressure of piezo-pump and the design of piezoelectric actuators,an approach according to the parameters of piezoelectric actuators is presented.Under the assumption of small elastic deformation,the equivalent concentrated force and output force coefficient of piezoelectric actuators are evaluated to investigate the output characteristics,and the corresponding formulas are deduced.The model is simulated by MATLAB.The affecting types of piezoelectric actuators parameters on the ultimate pressure of piezo-pump and the common scope are analyzed.The results show that the effect of elastic modulus of epoxy layer and Poisson＇s ratio of each layer can be neglected.When the thickness of plate is less than 0.8 mm,output pressure increases linearly with the thickness.When the thickness of plate is less than 0.4 mm and the piezoelectric layer less than 0.3 mm,output pressure increases significantly with the reduced thickness of piezoelectric layer.The calculation coincides with the experiment.