臺灣博碩士論文加值系統

摘要

本論文針對百葉窗型散熱片來作研究，以找出其表面特性與熱對流係數之關係，並對鰭片表面作不同切片時，熱對流係數的變化，以及對其熱傳導的影響，進而評估以基本理論做計算分析之可行性。
研究的方法是以基本理論配合數值計算的方法，以水力直徑 作為特徵長度，得到其相對應的雷諾數，再以平板流之紐塞爾數 理論，找出其熱對流係數以及熱傳因子 和摩擦因子 ，並以Wang [20]所提出的研究方法作應證，找出其相符之處，以及誤差的大小，接著再與平板型鰭片其熱傳性能及其壓降做比較。
結果發現以固定寬度對其鰭片做改變時，其切片對其熱對流係數 值的影響，與使用Wang[20]之法所計算出來的相符，而當對非固定寬度做討論時，則可得之使用基本理論法與Wang[20]之法所差異之處，而其熱傳性能比起平板型鰭片為佳，其熱對流係數 大約高有
，在 時，其百葉窗型鰭片的熱傳量比起平板型大約高出有 ，但其壓降卻也比平板型高出 。

ABSTRACT

This thesis is studied to the shutter type fin , in order to find out the relation between its surface characteristic and hot convection coefficient, and do a slice of surface of fin differently while cutting into slices, the change of hot convection coefficient, and the impact on its heat-conduction , and then assess the feasibility of making computational analysis with basic theories.
The method to study is the method of cooperating with number value to calculate with basic theories, regard diameter of water conservancy as the length of characteristic , get its corresponding Renaud to count , fills in and counts the theory in knob that and then flow with the plateform, find out its hot convection coefficient and heat and spread the factor and rub the factor, and do in conformity with the card with research approaches put forward of Wang [20 ], find out place that agree its, and size of error, slices of their hot to spread performance and is it is it compare to lower to pigeonhole with dull and stereotyped fin again then.
Found finally that while changing its fin slice with the regular width, it cut impact on its hot convection coefficient value into slices, conforming with used the law of Wang [20 ] to calculate out, and when discuss to the non- regular width , can must law place of difference of using basic theories the laws and Wang,and whether its the hot to spread compared with in fin not dull and stereotyped slice is good for performance , in when,its shutter the fins heat of stretch higher than not having compared with type not dull and stereotyped probably spreading amount, but it is also higher than the dull and stereotyped type that it is pressed and lowered.

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