本實驗主要目的為：藉由氣流旁通(partial bypass)的概念來改善鰭 管式熱交換器的性能。且特別在結露情形發生的條件之下探討氣流旁 通的概念是否能增加鰭管式熱交換器的性能。以下將整理氣流旁通概 念所帶來的效能分析。
(1) 對於兩排管熱交換器而言，在相對濕度為 50%時，旁通概念的效 應可以分成兩個部分:在低 BR 時，旁通效應會在低風速有較佳的 表現，以正向風速 0.5 m/s 為例，應用旁通概念的熱交換器其熱傳 量可能會比沒有應用旁通概念的熱交換器還要高或是維持水平，
但是壓降部分可以減少大約 6%。而在高 BR 時，旁通效應則會隨 著速度的增加而提升，但正向面速高於 2 m/s 後趨勢則會再往下 降。在風速為 2 m/s 時有較好的效應產生，以 BR=0.8 時為例，會 發現熱傳量減少了大約 17%，但是壓降部分卻可以減少 40%。
(2) 對於兩排管熱交換器而言，在相對濕度為 80%時，旁通概念的效 應比在環境濕度為 50%時好。而在低 BR 時，旁通效應會在低風速 時有較佳的表現。以風速為 0.5 m/s 為例，低 BR(0.0、0.2)的情形 之下應用旁通概念的熱交換器其熱傳量會比沒有應用旁通概念的 熱交換器還要高，直到 BR=0.4 時熱傳量還是可以維持水平。而壓 降部分的話到 BR=0.4 時可以減少約 15%之多。；在高 BR 時，旁 通效應則會在風速為 2 m/s 時有較好的效應產生。在 BR=0.8 的時
(3) 對於四排管熱交換器而言，在相對濕度為 50%時，整體來講四排 管的旁通效應會比兩排管的表現要來的更好。旁通概念的效應同 樣有兩種不同的趨勢。在低 BR 時，旁通效應會在風速為 0.5 m/s 時有較佳的表現；而在高 BR 時，旁通效應在風速為 2 m/s 時會有 較佳的表現。在 BR=0.8 的時候，可以發現熱傳量減少了大約 16%，
但是壓降部分卻可以減少 42%。
(4) 對於四排管熱交換器而言，在相對濕度為 80%時和環境濕度為 50%時，表現是差不多的。而且會發現，在環境濕度為 80%時，四 排管的旁通效應和兩排管的旁通效應其實差異也不大。而整體的 旁通效應會在風速為 2 m/s 時有較佳的表現，尤其是在高 BR 的時 候。在 Vfr = 2 m/s，BR=0.8 時，可以發現熱傳量減少了大約 14%，
而壓降部分可以減少約 40%。
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