本文使用三維CFD逆向方法搭配實驗量測特定點之溫度，經由最小平方法求得空腔內底部熱源及傾斜熱壁之未知熱源的Q值，再透過模擬軟體ANSYS Icepak選用適合的流動模型，透過改變三種變因，分別為不同的空腔高度、底部熱源大小以及底部熱源位置來探討在不同變因情況下，對於空腔自然對流的影響。使用ANSYS Icepak對網格進行測試，觀察不同的網格劃分結果對於空腔數值的影響，探討三角形空腔內自然對流的熱傳特性。
結果顯示，透過層流模型以及多種紊流模型與實驗值進行比較後，選用層流模型作為流動模式。藉由實驗數據搭配數值模擬結果之溫度分布圖及速度流線圖分析各種現象，隨著空腔高度逐漸增加，冷壁平均熱傳導係數隨之上升，空腔內更不易聚熱，並且空腔高度的改變對流場有著明顯的影響；底部熱源尺寸由小至大，則發現當尺寸越大，空腔對流提升，冷壁平均熱傳導係數上升；不同的底部熱源位置，由靠近中心逐漸往冷壁處接近，冷壁的平均熱傳係數有所增加，並且空腔內部流動有明顯的變化，特別是在靠近冷壁處。

In this study, a 3D CFD inverse method was used to measure the temperature at specific points. The unknown heat source Q value of bottom heat source and inclined hot wall in cavity were obtained by the least squares method. A suitable flow model was selected by using the simulation software ANSYS Icepak. The influence of different variables on the natural convection of the cavity is discussed with different cavity height, the size and position of the bottom heat source. ANSYS Icepak was used to test the mesh, observed the influence of different mesh division results on the cavity values, and discuss the heat transfer characteristics of natural convection in the triangular cavity.
The results show that laminar flow model is selected as the flow model after comparing the experimental values with laminar flow model and a variety of turbulent flow models. With the increase of the cavity height, the average heat conduction coefficient of the cold wall increases, and the heat is more difficult to accumulate in the cavity. The change of cavity height has obvious influence on the flow field. When the size of the bottom heat source increases from small to large, the convection in cavity increases and the average heat conduction coefficient of the cold wall increases. The average heat transfer coefficient of the cold wall increases, and the flow inside the cavity changes obviously, especially near the cold wall.

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