一种合成射流压电微泵关键结构参数确定方法

为增大无阀微泵流量,改进合成射流微泵设计方法,设计一种基于合成射流压电激励器的微泵结构,并提出关键结构参数的确定方法.在合成射流激励器流场模拟结果基础上,绘制其轴线上的轴向瞬时速度变化曲线以及出口横截面上的轴向速度分布曲线,利用轴线上轴向速度稳定点以及出口横截面上轴向速度分布曲线的零点确定最佳泵腔高度和出口直径.对所选用的合成射流激励器流场进行三维数值模拟,结果表明:利用该方法得到微泵结构的最佳泵腔高度为7 mm,最佳出口直径为1.78 mm.在零背压下,当雷诺数为225、频率为100 Hz时,该合成射流微泵流量可达32.1 m L/min.数值仿真与实验对比验证了方法的可行性.利用该方法可以有效地确定该类微泵在大流量且连续稳定出流性能下的关键结构尺寸.

Critical structure parameter determination method of a synthetic jet-based piezoelectric micropump

A valveless synthetic jet-based micropump structure was designed for transporting liquid and a critical structure parameter determination method was developed for the largest flow rate and steady outflow of the micropump. The critical structure parameters included the chamber height and outlet diameter of the micropump. The chamber height could be set at the position where the axial instantaneous velocity in the center axis was invariable. And the outlet diameter could be obtained by the jet boundary on the outlet cross section. A three-dimensional numerical simulation was carried out to obtain the performance of the micropump. The velocity boundary condition and the SST turbulence model were utilized in the numerical simulation. The simulation results of a synthetic jet actuator fit the previous experimental results well. The results suggest that the optimal chamber height and outlet diameter are 7 mm and 1.78 mm respectively. And the flow rate can achieve 32.1 mL/min at the 0 back pressure and Reynolds number of 225. It''s effective to design the chamber height and the outlet diameter of the micropump by this method to achieve the maximum flow rate and steady outflow.