无阀压电泵用椭圆组合管正交优化设计与试验

Orthogonal Optimization Design and Experiment of Oval Composite Tube in Valveless Piezoelectric Pump

为了提高无阀压电泵中流管的流阻特性,提出一种新型椭圆组合管结构。该流管为三通结构,汇流管是传统扩散/收缩管,分流管是椭圆曲线结构的扩散/收缩管。通过数值模拟,应用正交方法优化椭圆组合管的结构参数。设计选用的汇流管最小宽度d=150μm,流管深度H=150μm,优化结果表明当进出口压差为50 kPa时,结构尺寸为r=75μm,L=3 000μm,θ=7°,γ=80°,a=1 000μm,b=450μm的椭圆组合管有最高的正反向流阻系数比λ。通过MEMS技术制作出优化后的椭圆组合管并进行试验,并与数值模拟结果对比。结果表明:试验值小于模拟值,压差在10-100 kPa范围内,正向流量试验值与模拟值最大相差12.6%,反向流量两者最大相差5.3%;压差为50 kPa时,两者的λ值分别为1.83和1.97,相差7.65%。

In order to improve the characteristics of flow resistance in the valveless piezoelectric pump,a micro-flow tube called oval composite was presented.It＇s a kind of three-way tube,of which branch tube was composed of oval nozzle/diffuser elements and converging tube was composed of traditional nozzle/diffuser elements.In the numerical simulation,the orthogonal optimization was applied to obtain parameters of the proposed tube.The minimum width of converging tube d was 150 μm and the depth of the tube H was 150 μm.The optimization results showed that when the pressure difference between the inlet and outlet was fixed at 50 kPa,the highest coefficient of positive and negative flow resistance λ was achieved with optimization parameters of r = 75 μm,L = 3 000 μm,θ = 7°,γ = 80°,a = 1 000 μm,b = 450 μm.Then,the optimized composite tubes were produced though MEMS processing technology and the experiments were carried out and compared with the numerical simulations.The results showed that the experimental value was less than simulated value with pressure difference of 10 - 100 kPa.The positive largest mass flow difference between the experiment and simulation was 12.6%,and the negative was 5.3%.When the pressure difference was 50 kPa,λ was 1.83（positive） and 1.97（negative） with difference of 7.65%.