本文以有限差分法、最小平方法之逆算法搭配實驗溫度量測值來估算板鰭式熱沉垂直置放於封閉矩形外殼內之熱傳係數與散熱量，並以CFD探討鰭片間之空氣溫度與流場速度分佈情形。由於鰭片上的熱傳係數並非均勻分佈，故於進行反算前，須將鰭片分割為N個小區域，而後把熱電偶安裝於小區域上以量測不同條件下之量測位置的溫度。再以商用軟體FLUENT搭配各種流動模式及適當格點數目求取各量測點之鰭片溫度、鰭片上之熱傳係數。除此之外，在相同條件下由各種流動模式所求得之數值結果將相互比較，以探討其差異性。為求得本研究較正確之熱傳及流體流動特性，選用適當的流動模式及網格格點數所求得之鰭片熱傳係數，須盡可能接近實驗溫度量測值及逆算結果。結果顯示，流動模式及網格點數目對數值結果之影響不容忽視，實驗方面若將鰭片置於具有孔洞之封閉矩形外殼內，會因煙囪效應而增加自然對流效果，而鰭片上的平均熱傳係數會隨鰭片間距的增加而提高且隨著鰭片高度的增加而減少。此外對於鰭片排列方式的不同也有明顯差異，鰭片交錯式排列所得平均熱傳係數均高於直列式排列。為了驗證所得結果之可靠性及可用性，所求得熱傳係數之逆算結果將與先前結果或其他相關文獻之經驗式相比較。

In this paper, finite difference method, least square method and inverse method combined with experimental temperature data are used to estimate the heat transfer coefficient and the heat dissipating capacity of the plate-fin heat sinks which is placed vertically. Furthermore, CFD is used to discuss the air temperature and the flow field speed between the heat sinks. Due to the heat transfer coefficient of the plate-fin heat sinks is not uniform, so the plate-fin is required to divide into several regions. After that, install thermocouples on each small region, and measure the temperature of these places. Besides, any kinds of the various models will be compared with the numerical results on the same condition for find out the differences. To obtain correct heat transfer and fluid flow characteristics of plate-fin heat sinks, choose appropriate flow model and number of grid points is very important. The results indicate that the flow model and the number of grid points have a great influence on the numerical analysis. From the experiment point of view, the average heat-transfer coefficient will increase as the fin pitch increase but will decrease as the fin height increase. Besides, it will be significant affection in the arrangement of the heat sink. In terms of the heat transfer coefficient, Stagger array is higher than the in-line array. In order to verify the reliability of predicted results of this paper, the present study also in comparison with the empirical correlations of other relevant literature.

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