為探討在空腔內放置數個加熱器之自然對流的熱傳特性，本文以CFD軟體結合逆算法，並且使用最小平方法配合實驗量測之溫度點估計未知加熱量。藉由上述方法，找出與實驗數據最相符之流動模型後，可使用後處理呈現溫度場、流場等數值結果，分析數值與實驗結果進行比較與討論。為降低此方法所產生之誤差，探討網格的劃分及流動模型的準確性是必要的。結果顯示，在矩形加熱器置於空腔內時適合之流動模型為SST k- omega；圓柱形加熱器則是Laminar最適合。然使用不同數量、距離、形狀參數分析流場之性質可得，隨著加熱器數量增加的情況下，冷板之熱傳係數變化最高可達41.9 %；於空腔中所產生之流線單元與加熱器數量呈正比關係；當加熱器距離擺放變化時，流場型態有明顯影響；加熱器距離為60 mm、80 mm有較為完整的單元形狀。

This study investigated the natural convection heat transfer characteristics in a cavity using computational fluid dynamics (CFD) numerical simulation combined with the inverse method and obtained the unknown heat sources by the least square method. By this method, finding an appropriate flow model that the temperature distribution and flow field are presented by post-processing, which analyzed the impact of different parameters. In order to reduce the error of the method, it is necessary to consider the grid division and the accuracy of the flow model. The numerical results show that SST k-ω is closest to the experimental measurements of the rectangular heaters in this study and laminar is closest to the experimental measurements of the cylinder heaters. The flow field was analyzed using different numbers, distance, and shape parameters, and the heat transfer coefficient of the cold plate increased up to 41.9 % when the number of heaters was increased. The number of heaters increases proportionally to the number of cells. When the heater is placed at different distances, the flow pattern has a significant influence. The cells are more complete when the distance is 60 mm and 80 mm.

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