Investigations on performance of valveless piezoelectric micropump with concave tuning diffuser/nozzle elements in transient flow

Micro & nano letters

article

Xiuhua He¹  Jiawei Shi¹  Hang Yang¹  Nan Lin¹  Benjamin Bernard Uzoejinwa² 

[1] School of Energy and Power Engineering, Jiangsu University;Department of Agricultural and Bioresources Engineering, University of Nigeria

关键词: micropumps;    nozzles;    microchannel flow;    piezoelectric devices;    vortices;    numerical analysis;    flow simulation;    boundary layers;    flow separation;    valveless piezoelectric micropump;    concave tuning diffuser/nozzle element;    steady flow rectification;    straight sidewall;    pump efficiency;    concave tuning structure;    diverging angle;    transient flow;    numerical simulation;    vortexes;    pressure distribution;    characteristic Reynolds number;    adverse pressure gradient;    boundary layer separation;    channel flow;    frequency 10.0 Hz to 1000.0 Hz;   

DOI  :  10.1049/mnl.2018.5712

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

A diffuser/nozzle is one of the most frequently-used channels in a valveless piezoelectric micropump, but its efficiency has not been satisfactory. Hence, optimisation of the channel structure is of great significance. The concave tuning diffuser/nozzle element can obtain steady flow rectification under different Reynolds numbers, and its efficiency is much higher than the conventional diffuser/nozzle element whose diverging angle is >25°. Therefore, the application of concave tuning on the micropump is promising and worth anticipating. In this work, the experiment and numerical simulation were carried out under the conditions of voltage (50–250 vpp), excitation frequency (10–1000 Hz) and Re c (100–1000). The results show that the performance of a micropump with concave tuning is better than that with a straight sidewall, as the pump efficiency is improved significantly. The position and size of vortexes are of great significance to the pump efficiency of the micropumps. The distribution of pressure in the micropumps with concave tuning and straight sidewall was displayed. With the increase of characteristic Reynolds number, the adverse pressure gradient occurred. Compared with the straight sidewall, the concave tuning structure can better withstand adverse pressure gradient and delay the boundary layer separation in the channel.

【 授权许可】

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