双肋式微型气动阀的数值计算与实验

Numerical Simulation and Experiment on Two-riblet Micro Aerodynamic Valve

针对现有微型三角阀效率低的问题,提出双肋式气动阀这一新型微阀,通过两级带圆弧过渡的收敛形肋条,在减小正向气流压力损失的同时,引导逆向气流分为3股后再呈“Y”形汇聚,产生强烈的相互撞击而抵消部分动能,从而减小逆向流量以提高效率。通过数值计算对双肋式气动阀的作用原理进行了分析与验证;加工了特征尺寸为1 mm的三角阀、梯形阀与双肋阀实验件,并设计了相应的实验方案,在微流体实验平台上进行了对比实验。结果表明双肋阀能大幅提高效率：对不可压流,双肋阀可将效率从普通阀的2%-3%提升至14%左右;对可压流,双肋阀能将效率从2%提升至约13%。

The two-riblet micro aerodynamic valve is presented in this article to solve the low-efficiency problem of the micro triangular valve. Based on two-stage contractive riblets with transition arc, the two-riblet aerodynamic valve reduces the pressure loss of the airflow in the positive direction, and divides the airflow in the negative direction into three currents. The three currents converge in ＂Y＂ shape afterwards, collide with each other intensely and then dissipate some kinetic energy, leading to the reduction of mass flow rate in the negative direction and the increase of the valve efficiency. The working principle of the two-riblet aerodynamic valve is studied and testified by numerical simulation. The triangular, trapeziform and two-riblet aerodynamic valve samples with a feature size of 1 mm are fabricated by means of wire-electron discharge machining and EDM. A new experiment method is designed and experimental studies are carried out on micro flow testing platform. The results show that the two-riblet aerodynamic valve improves efficiency remarkably： under incompressible condition, the efficiencies of the triangular and trapeziform valves are around 2 %-3 %, and that of the two-riblet aerodynamic valve is about 14% ; under compressible condition, the two-riblet aerodynamic valve enhances the efficiency to 13% as compared with 2% of the other two valves.