本研究主要目標為討論市面上之微機電氣體流量計，依照其基本運作原理，建立簡化之流場模型，並針對為該流場進行分析。利用GAMBIT 2.4建立模型及網格，並利用ANSYS 13.0之FLUENT進行模擬計算。此流量計模型利用主流道之「壓降元件」使上下游之間產生明顯壓降，成為足以推動流體進入「旁通流道」之壓差，旁通流道之進出口內設有多孔板以整流並控制流量。此微小流量於旁通流道中，經過本流量計之核心「晶片感測區流道」，該處流道為微米尺度，故可以層流模型進行計算。其晶片中央為一發熱線路區，兩側各有一組感測線路區，流體靜止時，兩感測區之溫度相同；而當流體流動，因兩者分別位於熱源上下游，而產生溫度差異，可由此溫度差異與變化趨勢，建立流量與溫差之關係。本研究包含兩類主流道壓降元件，其中一種設計於主流道中央設置一片多孔板，另一種則設置收縮通道(orifice)。分析多孔板結構時，將多孔板以等效壓降取代；分析收縮通道時則直接採實際之幾何外型進行模擬計算。整理各個條件下之主流道流速、旁通流比率與溫度變化之關係，可推得流量計之輸入流量與晶片溫度差異之間的關係，藉此建立量測依據，並比較各範圍下晶片感測之靈敏度。

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