柔性尾长对尾鳍式压电泵的影响

为克服传统的容积型无阀压电泵存在的流动波动大、有回流、泵水能力差等通病,提出并设计模仿鱼尾摆动的无阀泵,并针对具有柔性尾鳍的变截面摆动子进行研究。在研究巡游速度最大的金枪鱼尾鳍摆动的基础上,设计具有柔性尾鳍的变截面摆动子;基于有限元分析软件ANSYS进行摆动子在水中的谐响应分析,提取不同长度的柔性尾鳍工作在二阶谐振下的端部振幅,分析表明,摆动子端部振幅对泵的理论流量影响较大;利用电荷耦合器件(Charge coupled device,CCD)激光位移传感器对摆动子的端部振幅进行测量,柔性尾鳍长度为5 mm时,摆动子的二阶弯振端部振幅达到0.4 mm,端部振幅随柔性尾鳍长度变化的趋势和ANSYS分析结果一致;对泵进行试验研究:在60 V的电压的激励下,柔性尾鳍长度为5 mm时,泵的压差达到78 mm。研究表明,在摆动子的其他结构参数一定的情况下,泵的性能对柔性尾长较为敏感,并存在最优的柔性尾鳍长度值。

Influence from Length of Flexible Caudal-fin for Caudal-fin-type Piezoelectric Pump

In order to overcome existing common faults of the traditional volumetric type valve-less pump,such as fluctuation,backflow and lack ability of pumping,a valve-less pump which imitates the swing of the caudal-fin is proposed.The researches on the variable-cross-section oscillating vibrator with flexible caudal-fin are carried out.Based on the study carried on the swing of the tuna which has high cruise speed,a variable cross-section vibrator with flexible caudle-fin is designed.The harmonic analysis of vibrator immerged in water is conducted with the ANSYS software.The tip amplitude of vibrator,which has different flexible caudal-fin length,is extracted when the vibrator operates in the second order bending mode.The analysis results suggest that the tip amplitude has great influence on the theoretical flow rate.Thirdly,the tip amplitude is measured utilizing a charge coupled device(CCD) laser displacement sensor.When the length of the flexible caudal-fin is 5 mm,the tip amplitude of second bending mode reaches 0.4 mm.Meanwhile,the trend of the tip amplitude,which varies with the length of the flexible caudal-fin,coincides with the result of simulation.Finally,the performance of the pump is tested experimentally:Driven by 60 V AC signals,the pressure head reaches 78 mm when the length of the flexible caudal-fin is 5 mm.This research reveals that when the other structure parameters are fixed,the length of the flexible caudal-fin determined the performance of the pump.