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本文使用CFD软件FLUENT,研究了一种新型电加热方法产生热力汽泡驱动的无阀微泵.得出了不同加热壁面过热度下泵流量和泵压与驱动频率的关系.无阀微泵200μm深,驱动腔为直径1mm的圆腔,一对最窄为30μm最宽为271μm、张角7°的微扩管被分别连接到驱动腔,工质为甲醇,采用层流模型.研究表明不同加热壁面过热度有不同的最大流量驱动频率,在过热度为ΔT=15°C时,最大体积流量为9.02μL/min,最大的泵压为680Pa.随着壁面过热度增加,包含汽泡生长和冷凝周期的时间会变长,导致泵送的流量受到显著影响;不同的壁面过热度有不同的最佳驱动频率,过热度增加,最大的泵送流量和压力会增加而且有相似的变化趋势,最佳驱动频率会降低;供液期较泵送期长.
In this paper, we use CFD software FLUENT to study a new type of valveless micro-pump which is driven by thermal bubble and obtain the relation between pump flow rate and pump pressure and drive frequency under different heated wall superheat. The driving cavity is a circular cavity with a diameter of 1mm. A pair of micro-expanding pipes with the narrowest width of 30μm, the widest opening of 271μm, and the opening angle of 7 ° are respectively connected to the driving cavity with a working fluid of methanol using a laminar flow model. Heating wall superheat has different maximum flow driving frequency, when the superheat is ΔT = 15 ° C, the maximum volume flow is 9.02μL / min, the maximum pump pressure is 680Pa. With the increase of wall superheat, And the condensation cycle time will be longer, resulting in a significant impact on the pumping flow; different wall superheat have different optimal driving frequency, superheat increases, the maximum pump flow and pressure will increase and have similar trends , The best driving frequency will be reduced; the liquid supply period is longer than the pumping period.