本文以理論分析及實驗探討擴散排列之波浪形渦流產生器(vortex generator)之鰭管式熱交換器的熱增強現象，是利用裝置於鰭管式熱交換器鰭片上之凸起物，使空氣流經渦流產生器時產生縱向渦漩以增進熱傳的裝置。理論方面以三維延伸κ-ε (extended κ-ε model)紊流模式，探討在不同正向流速下及不同渦流產生器之展開角度，對熱傳(Colburn因子，j)及阻力(阻力係數f)的影響。實驗部分以水洞做流場觀測，相互印證所採用的物理模式及數值方法的準確性。
從理論分析結果得知，鰭管式熱交換器使用擴散排列之波浪形渦流產生器在熱傳方面，VG1(展開角度為30度)j值最大可增加達7.8%，VG2(展開角度為45度)可增加20.2%，而VG3(展開角度為60度) 可增加25.7%；在阻力方面，VG1之f值最大可增加4.3%，VG2可增加14.7%，VG3可增加26.3%；而基於同樣熱傳量需求和風扇功率的條件下，整體熱交換面積縮減率以VG2的效果最好，可達到24.0%~12.0%。
從流場觀測結果得知，渦流產生器一方面可使流体導入圓管後方將迴流區熱量帶出，而且加速流體衝擊下一排圓管，提高下一排圓管前端之熱傳效率。另一方面可使流體衝擊渦流產生器後，在渦流產生器下游形成縱向渦漩，使下游區域混合增加。在壓降方面，數值結果與實驗比對平均稍低估約15~25%。

Experimental and numerical analyses were carried out to study the heat transfer and flow in the plate finned-tube heat exchangers with inclined block shape vortex generators mounted behind the tubes. The study was performed for a variety of span angle over a range of flow conditions. Experiments were examined by a water tunnel system to visualize local flow structure. In addition, numerical simulation was performed by a 3-D turbulence analysis of the heat transfer and fluid flow. The results indicated that the proposed heat transfer enhancement technique enable to generate longitudinal vortices and to improve the heat transfer performance in the wake regions. These effects were intensified as the span angle is increased. Furthermore, the case of 45°span angle provides the best heat transfer augmentation. A reduction in fin area of 24% may be obtained if vortex generators embedded fins are used in place of plain fins.

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