无阀压电泵用平面锥管的非稳态特性研究  

Transient Characteristics of Flat-Walled Diffuser/Nozzle Elements of Valveless Piezoelectric Micropumps

作　　者：何秀华[1] 蔡盛川[1] 邓志丹[2] 杨嵩[3] 韦丹丹[1] 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013 [2]江苏大学理学院,江苏镇江212013 [3]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《西安交通大学学报》2014年第5期89-95,共7页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51276082);江苏高校优势学科建设工程资助项目

摘　　要：利用CFX软件在不同Womersley数(Wo)下对锥角为5°和10°的平面锥管的非稳态特性进行了数值模拟研究,目的在于获得非稳态条件下影响无阀压电泵用平面锥管流动特性的因素。锥管进口设为随时间按正弦规律变化的压力边界条件,压力幅值分别取0.5、1和5kPa。结果表明:流量变化滞后于压力变化,且Wo越大,压力幅值越小,相位差越大;净流量随压力幅值和锥角的增大而增大;锥管扩散方向和收缩方向的压力损失系数随Wo的增大而增大,随压力幅值和锥角的增大而减小;低Wo下,压力幅值越大,微泵的整流效率越高,高Wo下,压力幅值越小,整流效率越高;非稳态流动产生的旋涡对无阀压电泵的输出性能有重要影响。Transient behaviors of flat-walled diffuser/nozzle elements are numerically characterized in the case of diffuser angles of 5°, 10° and various Wo numbers. For obtaining the factors affecting flow characteristics of the micropumps under unsteady conditions, a time-dependent sinusoidal pressure with amplitudes of 0.5, 1 and 5 kPa is applied on the inlet. The results show that the variation of flow rate lags the variation of pressure, and the greater Wo numbers, or the smaller pressure amplitude, the greater phase difference appears; net flow rate increases with increasing pressure amplitude and diffuser angle; both the pressure loss coefficients of the diffuser and nozzle increase with increasing Wo numbers, and decrease with increasing pressure amplitude and diffuser angle. The rectification efficiency of micropumps increases with increasing pressure amplitude for smaller Wo numbers, whereas increases with decreasing pressure amplitude for greater Wo numbers. The vortex generated by transient flow exerts obvious influence on the output performance of valveless piezoelectric micropumps.

关 键 词：无阀压电泵 平面锥管 非稳态特性 数值模拟 

分 类 号：S277.9[农业科学—农业水土工程] TH38[农业科学—农业工程]