在工業程序中，化學工程師所執行的各種操作均會涉及到能量的交換，而這些能量通常以熱的形式出現，因此熱交換裝置在工業上扮演了相當重要的角色。 流體流經熱交換器的方式有同向流、逆向流及交叉流，本研究的研究對象為非穩定性交叉流熱交換器。交叉流熱交換器通常應用於氣體的加熱或冷卻，所以相關於氣體流經交叉流熱交換器的研究較多。 由於電腦的快速發展，工業也朝向自動控制化發展。為了節約能源，當熱交換器處於非穩態下的控制，就是利用電腦來自動控制以達到穩態。利用電腦模擬出熱交換器處於非穩態下所呈現出的溫度分佈是一個相當方便且節省研究費用的方法。 本研究之主要目的為利用有限差分數值分析法及Fortran電腦語言發展一套模擬非穩態下流體流經平板之交叉流熱交換器後的熱傳導程式。就不同參數探討系統處於非穩態下的溫度分佈，以利於日後工程人員作為設計一個高熱傳效率之熱交換器的參考。 In industrial processes , most operations operated by a chemical engineer will involve with energy exchange . And the energy usually is performed in heat form . So the heat transfer instrument is important in industrial operations . The ways , which the fluid flow through a heat exchanger , are parallel-flow , counter-flow and crossflow . Our research is the crossflow heat exchanger in unsteady state . The crossflow heat exchanger usually be applied in heating or cooling gas . So the research in gas thruogh a crossflow heat exchanger is numerous . The main purpose of this research is to analyze the unsteady state plate type crossflow heat exchanger with finite difference numerical method . We discuss the unsteady state temperature distributions with different parameter which are stated in this study .
