Abstract：In order to precisely get the cavity volume fluctuations of piezoelectric pumps in operation, the deformation characteristic of a circular piezoelectric vibrator, which was one key factor to be responsible for the cavity volume fluctuations, was analyzed and measured in a noncontact manner. The experiment model was a circular piezoelectric unimorph vibrator with substrate and ceramic in the diameters 65 mm and 60 mm,respectively.The relations of amplitude of the center point on the vibrator plane to frequency, driving voltage, and those of amplitude of the points distributed radially in the vibrator subject to a sinusoidal voltage were studied. Based on quadratic functions, the amplitude of each point on the radius was fitted to get the deformation curve by using a Matlab code. According to the fitted curves, a theoretical method for estimating the cavity volume fluctuations was established. The results show that the amplitude of the center point decreases with frequency but increases with driving voltage; the amplitude of each point on the piezoelectric vibrator decreases with radius; the fitted results agree well with the experimental data and the maximum relative error is 6.96% only. According to the theoretical method proposed, it is predicted that under the excitation of sine voltage of 100 V, 30 Hz, the volume fluctuation of pumping cavity is 34.009 mm3, and the theoretical maximum output flow rate is 61216 mL/min.
［1］Ashraf M W , Tayyaba S, Nisar A, et al. MEMS based system for drug delivery\[C\]∥ Proceedings of 6th International Conference on Emerging Technologies (ICET), Islamabad: IEEE Inc. Islamabad Section & National University of Computer and Emerging Sciences (NUCES), 2010: 82-87. ［2］孙晓峰，杨志刚，姜德龙. 两种双腔串联压电泵结构设计与性能比较\[J\]. 排灌机械工程学报，2011,29(1)：31-34.Sun Xiaofeng, Yang Zhigang, Jiang Delong. Structural design and performance comparison of two kinds of piezoelectric pump with two chambers in series\[J\]. Journal of Drainage and Irrigation Machinery Engineering, 2011, 29(1): 31-34. (in Chinese)［3］Kim H H, Oh J H, Lim J N, et al. Design of valveless type piezoelectric pump for microfluid devices\[J\]. Procedia Chemistry, 2009, 1(1):353-356.［4］De Lima C R, Vatanabe S L, Choi A, et al. A biomimetic piezoelectric pump: Computational and experimental characterization \[J\]. Sensors and Actuators, A: Physical, 2009, 152(1): 110-118. ［5］Kan Junwu, Tang Kehong, Liu Guojun, et al. Development of serialconnection piezoelectric pumps\[J\]. Sensors and Actuators, A: Physical,2008，144(2): 321-327.［6］Papila M, Sheplak M, Cattafesta L N. Optimization of clamped circular piezoelectric composite actuators\[J\]. Sensors and Actuators, A: Physical, 2008,147(1): 310-323.［7］黎毅力，张建辉，路计庄,等. 泵用压电振子动态特性的研究\[J\]. 中国机械工程，2007,18(17):2088-2093.Li Yili, Zhang Jianhui, Lu Jizhuang, et al. Research on the dynamic characteristics of the actuator for the piezoelectric pump\[J\]. China Mechanical Engineering, 2007, 18(17): 2088-2093. (in Chinese)［8］Fox C H J, Chen X, McWilliam S. Analysis of the deflection of a circular plate with an annular piezoelectric actuator\[J\]. Sensors and Actuators，A: Physical,2007, 133(1): 180-194. ［9］程光明，铃木胜义，广濑精二，等. 压电泵泵腔体积变化量研究\[J\]. 压电与声光，1998，20(6)：389-392.Cheng Guangming, Katsuyoshi Suzuki, Seizi Hirose, et al. Research on the cavity volume fluctuations of piezoelectric pump\[J\]. Piezoelectrics & Acoustooptics, 1998, 20(6): 389-392. (in Chinese)［10］李鹏. 主动阀压电泵的理论与试验研究\[D\]. 长春：吉林大学机械科学与工程学院，2007.
