微機電系統整合微感測器、微致動器、微控制器及微結構等元件於一裝置，以構成具有特定功能之系統，其中，微流體系統是一項極重要之主題，其必須發展的關鍵元件包括：微型閥、微流量感測器、微通道結構、微型泵等。針對微型泵而言，傳統利用薄膜作動而產生機械式開關動作，容易因為壓力降變化而導致閥門磨損，而且薄膜作動將產生脈衝式流動而非連續式，若能夠應用非機械式驅動力以推動流體，則可避免上述問題。故本研究之目的即希望利用電磁場互動所產生之羅倫茲力來推動可導電流體，以省卻不必要之薄膜組件，且利用交流電以避免水溶液電解的問題。
本研究針對電磁場驅動導電流體流動之理論進行分析，在一維理論分析中，使用那維爾-史脫克方程式推導出包含電磁效應的流場方程式，採用生理食鹽水作為導電流體，建立等效迴路模型。利用電子電路設計分析軟體設計交流放大電路與有限元素軟體設計電磁鐵磁通密度，研究流道尺寸、交流磁場、交流電場和交流電頻率等變異數，討論一可行交流磁流式微型泵參數。

Micro Electromechanical System technology integrates micro-sensors, micro-actuators, micro-controllers, and micro-structures into a silicon device with specific features as a system. In particular, micro fluid devices have been especially important because many key components, namely valves, flow sensors, channels, and pumps, have been developed for industrial applications in recent years. Among the above components, traditional micro-pumps have employed thin films for generating mechanical motions that induce valve wear due to pressure variations; and, with vibrating thin films the micro-pump cannot deliver continuous flow. Therefore, the objective of this study is to investigate the pumping effects of electromagnetic Lorentz force in electric-conducting liquid driven by alternating current so that electrolysis of fluid can be circumvented.
This thesis is to study and analyze the electromagnetic Lorentz forces in electric-conducting aqueous saline solutions submerged under alternating magnetic field. In 1-D flow analysis, Navier-Stokes equations are simplified for solving flow field under electromagnetic interactions driven with alternating currents under closed-loop control. Furthermore, electronic circuit analysis software has been used for designing the power operational amplifier circuits together with the magnetic circuits being simulated via Finite Element Method programs. Effects of size on the flow channel, the AC magnetic field, the AC electric field, and the operating frequency have been carefully studied so that conclusions for assessing design parameters for a practical AC operated MHD micro-pump are made.

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