本文為探討空腔中自然對流之熱傳性質，使用三為CFD逆向方法配合實驗結果設置十個個溫度量測點，並搭配CFD商業模擬軟體 ANSYS Icepak 18.0，並探討不同流動模式與網格劃分對於不同物理模型的適用度，再利用最小平方法修正空腔中為之熱源之Q值，以接近實驗量測結果，符合整體趨勢，最後將模擬結果之溫度分布圖和速度流線圖，使流場可是化並配合實驗數據分析其熱傳特性。
結果顯示，流動模式和網格點數目對結果影響很大，而實驗方面，隨著空腔大小的變化以及開口的影響，空氣流動會有所不同，也會因封閉變成開放的空腔模型，達到增強自然對流的效果，由於大量冷空氣流入，雖使空腔整體溫度大幅下降，卻使上方冷壁被冷空氣包圍，使熱傳係數下降。為了驗證本文逆算法之結果之可靠性跟可用性，所求得的熱傳係數與散熱量之結果與先前結果或其他相關文獻之經驗公式互相比較。

In this paper, to investigate the heat transfer properties of natural convection in a cavity, we use the inverse method of Sanwei CFD with experimental results to set ten temperature measurement points and the CFD commercial simulation software ANSYS Icepak 18.0, and explore the applicability of different flow patterns and grid delineation to different physical models. Finally, the temperature distribution and velocity flow line of the simulated results are used to visualize the flow field and analyze the heat transfer characteristics with the experimental data.
The results show that the flow pattern and the number of grid points have a great influence on the results. In the experiment, the air flow varies with the change of the cavity size and the effect of the opening, and the closed cavity becomes an open cavity model to enhance the effect of natural convection. In order to verify the reliability and usability of the results of the inverse algorithm in this paper, the obtained heat transfer coefficients and heat dissipation amounts are compared with the previous results or empirical formulas from other related literature.

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