本實驗主要目的為：改善交錯型鰭管式熱交換器的熱傳性能，利 用修正型的凹窩當作渦流產生器，試圖在適量增加壓降範圍內，增加 熱傳性能，最後會將平板、VG、百葉窗三種鰭片作分析，如下：
(1)在鰭片間距皆為 1.6mm 的情況下，單排管時，VG 型在熱傳 係數大概上升 5~8%，壓降部份大約有 25~30%的上升；百葉窗型雖 然在熱傳係數方面增加較多，有 15~30%的提升量，但也伴隨著 40~50%的壓降增幅。在兩排管時，VG 型提升了 10~15%的熱傳，壓 降也增加約 30~40%；百葉窗型則是有 20~30%的熱傳改善，但壓降 也增加較多，大約增加有 35~50%。在四排管時，不管 VG 還是百葉 窗型，其熱傳與壓降的表現皆與兩排管類似。
(2)在鰭片間距為 2.0mm 時，單排管的 VG 型鰭片，熱傳係數增 加了 8~13%，壓降也同時上升了將近 40%；而至於百葉窗鰭片，在 熱傳係數較平板多出 8~20%，但壓降也多了 35~50%。至於在兩排管 時，VG 型的熱傳係數則是增加約 15%，壓降則是增加 35%左右；百 葉窗型分別增加 17%、40%。四排管時，這兩者的差異性就相當小，
熱傳係數差不多皆增加 17%，壓降約多 38~40%。
(3)鰭片間距由 1.6mm 增至 2.0mm 時，對於百葉窗型鰭片的熱傳 影響甚大，在風速較低的情形下，VG 型鰭片的熱傳效果會較佳。
(4)本實驗使用 VG-1 以及 FG-3 評價方法，結果皆說明：在多數 的情況下，當間距為 1.6mm 時，使用百葉窗型鰭片會是較佳的選擇。
但是，當間距增加，反而會使得 VG 型整體效率提升。
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