本研究擬運用三維逆向熱傳方法配合最小平方法進行數值分析，並透過模擬軟體Ansys Fluent 18.0模擬實驗之流場及溫度分布狀況。本研究架設一水平雙層平板，分別為聚丙烯及中碳鋼，藉此模擬燃燒室外殼之設計及觀察熱由中碳鋼傳遞至外界對周圍空氣所產生之影響，並利用CFD模擬軟體進行暫態數值預測物理性質例如熱傳率及熱傳係數隨時間之變化。
由模擬結果可知，在暫態分析的過程中，本研究從剛開始加熱到最後穩態階段流場主要可分為三個階段，分別為層流區、過渡區及紊流區，同時在每個不同區域會有不同適用之流動模型，本研究將透過均方根誤差、流線分布、熱板上之熱傳係數及最大速度進行流動模型判斷，選擇在各階段最適用之流動模型。

In this paper, an upward-facing horizontal double-plate with natural convection is discussed. Predicting unmeasurable physical properties like heat transfer rate (Q) and heat transfer coefficient (h ̅) through experimental data combined with numerical simulations.
According to the result, the flow field can be divided into three different stages from transient to steady state. When Ra<2.02×10^5, the flow field is in the laminar stage. When 2.02×10^5<Ra<1.01×10^7, the flow field is in the transition stage. Lastly, when 1.01×10^7<Ra, the flow field is in the transient stage. In addition, different stages have different suitable flow models. Therefore, it is important to choose the appropriate flow model in numerical simulation.

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