本文分別以理論分析及實驗方法探討矩形鰭片鰭管式熱交換器之熱液動性能，其中橢圓管長短軸比為(2.83：1)。在理論分析方面，利用二維鰭片效率分析法(two-dimensional fin efficiency analysis)之數值運算方式計算出鰭片熱效率，藉此分析矩形鰭片在全乾、半乾濕以及全濕之情況下對於熱交換器之整體性能的影響。在實驗測試方面，利用吸入型開放式熱交換器風洞測試系統，針對矩形鰭片鰭管式熱交換器分別在乾、濕盤管操作條件下，量測不同鰭片高度及不同管排列方式時的管外側熱傳係數及壓降特性曲線。

在理論分析方面詳述矩形鰭片的二維溫度分佈場以及探討鰭片熱效率與空氣相對溼度之間的關係，由於當熱交換器應用在除濕時、針對空氣冷卻時是否有凝結水產生與否，鰭片之狀況可分為全乾式、半乾濕式及全濕式三種情形。由理論結果發現到，鳍片高度7mm與10mm下的乾式鰭片熱效率分別較全濕式熱效率高18％及25％，鰭片熱效率於全乾式時鰭片熱效率將與空氣相對溼度無關，但是在半乾濕時，鰭片熱效率則會隨著空氣相對溼度增加而快速下降，而在全濕時鰭片熱效率僅隨著空氣相對溼度的增加而略為下降。

由實驗結果發現在入口風速1~6 m/s下，當空氣通過乾、濕盤管時，空氣側熱傳係數會隨著正向速度的增加而增加，其中交錯排列矩形鰭片鰭管熱交換器的熱傳因子j與顯熱熱傳因子js(Test Section A and C)比對齊排列矩形鰭片鰭管的j與js(Test Section B and D)高15~36％。而在濕盤管質傳因子jt與雷諾數之關係中，交錯排列(Test Section A and C)比對齊排列(Test Section B and D)的jt高20~36％。

由熱交換器性能測試實驗中發現，交錯排列矩形鰭管鰭管式熱交換器的壓降因子f值 (Test Section A and C)比對齊排列(Test Section B and D)高15~30％，且濕盤管的壓降因子f較乾盤管高6~12％。

The present investigation is to examine experimentally and numerically the thermal-hydraulic and mass transfer characteristics for rectangular finned-tube heat exchangers with elliptic tube having axis ratio of 2.83:1. Four types of finned-tube configurations have been investigated under the dry and wet conditions for different values of inlet frontal velocity ranging from 1 to 6 m/s. The results indicated that the sensible Colburn factor js, and the friction factor f for the wet coils are, respectively, 15 ~ 36 % and 6 ~ 12% higher than those for dry coils. The j, jt, and f with staggered arrangements are, 15~36％ 20~36％ and 15~30％, respectively, high than those for the in-lined arrangements. In addition, a two–dimensional fin efficiency analysis for the rectangular fins with elliptic tube with fin height 7mm and 10 mm are presented for a wide range of air relative humidity. It is shown that the fin efficiency is decreased with the increase of relative humidity, and the fully wet fin efficiency are 18％ and 25％ lower than that for a dry fin, respectively.

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