本文利用計算流體力學應用在鰭片式熱交換器之流道作熱流特性分析，分析鰭片包含窩形流道的三種參數變化和改變流道型式的錐形流道，探討其幾何與熱傳效率及阻力關係。文中分兩大部分，先以窩形流道為主軸，探究窩形流道改變幾何參數後對於熱傳及流體的變動關係；接下來將表現優異的窩形流道，在保留參數和一般條件，以改變型式為錐形的情形下，來比較之間的差異性。
增加窩形深度能加強熱傳，但是會使阻力上升；縮小窩形直徑熱傳會些微增加，不過阻力大幅上升，而窩形流道中窩形直徑與深度比為5時，擁有較佳的散熱效率。錐形設計較窩形能降低摩擦係數，由流場觀之錐形較窩形產生較小的渦流。實驗結果顯示窩形比錐形設計能有效的增加較大範圍的渦流，進而提高散熱效率。

In this thesis using Computational Fluid Dynamics applications to discussed the heat transfer and flow performance for fin-type exchanger channel characterization. Investigations of dimples channel containing three parameters flow and changes patterns of the cones channel to analysis the geometry with heat transfer efficiency and resistance relationships. There have two part in this thesis, at first to study dimples channel which are changes geometric parameters for heat transfer and fluid in the relationship. Second, retain the outstanding performance of the dimples channel in general conditions then change the pattern for the cone case, and compare the differences between.
Heat transfer can be enhanced by increase the depth of dimple-shaped, but the resistance will also increase. Narrow diameter of dimple-shaped that heat transfer will increase slightly, but increased the resistance too, and the dimple-shaped channel diameter and depth in the ratio of 5 have the best heat dissipation efficiency in this study. Cone-shaped design is lower than dimple-shaped of the coefficient friction. The cone-shaped vortex is smaller than the dimple-shaped vortex from streamline of view. The results show dimple-shaped can effectively increase the wide range of eddy current than cone-shaped design, thereby increasing the cooling efficiency.

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