根據生物心臟瓣膜的收縮和擴張機制，本研究提出了一種仿生導流結構，並將其放置於傳統圓形腔室的微泵。該微泵是由一個單晶PZT-4A微致動器和1:5比例混合而成聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)材料所組成，其作用分別是流量控制以及提供流場導流。
本研究採用弱形式“流-固耦合”建模方法模擬微泵的流場特性，然後為了確保導流結構能產生足夠的整流效果，重新設計PDMS導流結構的幾何參數，進而提升微泵的淨流量與最大背壓達10%以上。數值結果表明導流結構所劃分的前腔室尺寸約6.5 mm、結構厚度為0.1 mm且導流口角度為20°時，微泵可以同時提昇淨流量與最大背壓達10%以上。時序分析結果表明共振特性與流體渦流之耦合效應，使導流結構產生約五倍薄膜變形量的動態響應，具有提高腔室內的壓力擾動且誘發入口處的抵抗渦流，進而降低微泵的回流效應。
研究結果表明PDMS仿生微泵可以高效運作於背壓15-35 cm H2O與流量1.01-2.60 ml/min的操作區間。通過PZT-4A的電頻轉換進行微流量控制並滿足高效液體生醫裝置的微流量控制環境，即0-2.5 ml/min。

In this study, the mechanism of contraction and expansion rectification of the biological heart is investigated. The bionic diversion structure is thus proposed and placed in a traditional circular chamber of the micropump. The micropump is composed of a unimorph PZT-4A actuator and a 1:5 polydimethylsiloxane (PDMS) material. The functions of structure are to control the flow rate and to provide a flow-field diversion to improve efficiency of the system.
The weak form of "fluid-solid coupling" modeling method is introduced to characterize the flow field of the micropump. The method is used to ensure that the structure can produce a good rectification effect, the geometric parameters of the PDMS diversion are carefully designed to enhance both the net flow rate and back pressure of the micropump for more than 10%. The results of time domain analysis show that the coupling effect of resonance characteristics and inlet vortices of the chamber makes the diversion produce a dynamic response of approximately five times of the traditional membrane deformation. By so doing, it does improve the pressure disturbance in the chamber and induce inlet vortices to reduce the backflow effect of the micropump.
The results of this study also show that the PDMS bionic micropump can operate highly effective in the back pressure range of 15-35 cm∙H2O and a flow rate in the middle range of 1.01-2.60 ml/min. The high electrical frequency of PZT-4A is employed to control the flow rate to meet requirement of the microfluidic environment of the proposed efficient biomedical device for 0-2.5 ml/min.

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