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水平鰭片置於封閉空腔內之熱傳係數，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，實驗方面將水平鰭片置於封閉空腔中，探討鰭片間距和鰭片長度的變化所造成的影響，並研究不同鰭片位置之散熱差異。結果顯示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長度的增加而減少。此外不同位置的鰭片亦會隨著這些變化有所不同。為了驗證所得結果之可靠性及可用性，將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，且依現有的實驗數據改良經驗公式。

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 space increase but will decrease as the fin length increase. Besides, it will be significant affection with the different location in the cavity. In terms of the heat transfer coefficient, different fin locations have differnet heat dissipating capacity. 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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