单腔体气体压电泵设计

Design of single-chamber gas piezoelectric pump

为制造输出性能良好的气体压电泵,设计了一种新型的伞形橡胶阀.分析了伞形橡胶阀的过流特性,并应用Ansys软件,对阀的工作性能进行仿真分析,确定了伞形橡胶阀的前10阶固有频率和阀工作失效时作用在阀两侧的临界压力值.仿真结果表明:在泵工作频率低于阀一阶固有频率时,且当作用在阀两侧的临界压力值大于0.8 kPa时,阀因为开启高度过大而不能恢复到关闭状态导致泵工作失效.并对泵用压电振子在泵送气体时进行了发热性能测试以及应用伞形橡胶阀所设计的单腔气体压电泵进行输送气体和液体试验,试验结果表明:在110 V正弦交流电压驱动下,驱动电压频率小于400 Hz时,振子的热平衡温度小于70℃;输送气体时,在最佳工作频率为380 Hz时,最大输出流量和压力分别为1 889 mL/min和5.1 kPa;输送液体时,在最佳工作频率为240 Hz时,最大输出流量和压力分别为300 mL/min和25.0 kPa.

In order to fabricate gas piezoelectric pumps with better performance, a new type of umbrel- la-shaped rubber valve was designed. The discharge coefficient of that valve was analyzed, and the valve performance was simulated by applying Ansys software. Consequently, the natural frequencies from first to tenth order and the critical pressure difference across the valve under which it will be fai- lure were determined. The resuhs showed that the pump breaks down, i. e. , its valve cannot close by itself properly due to a too large opening height, if the pressure difference across the valve is higher than the critical value 800 Pa, when working at a fl＇equency lower than the first-order natural frequency of the valve. Also, the thermal performance of the piezoelectric vibrator was measured when pumping air. It was showed that the temperature of the vibrator at thermal equilibrium is less than 70 ~C when it was driven 110 V voltage at a less than 400 Hz frequency. A single-chamber gas piezoelectric pump with the newly designed umbrella rubber valve was tested by using air and water. It was showed that for air the optimum working frequency is 380 Hz, and the maximum output flow-rate and pressure are l 889 mL/min and 5.1 kPa; for liquid, however, the best working frequency is 240 Hz, and the maxi- mum output flow-rate and pressure are 300 mL/min and 25.0 kPa. These results confirm that the sin-gle-chamber gas piezoelectric pump has a better capability of pumping gas.