近年來，渦流產生器(Vortex generaror)常是被考慮為被動式熱傳增強技術的一種，它是利用一些小型凸出物，以浮花壓製(emboss)、黏附(stamp)、衝孔(punch)…等加工方式結合於主要的熱交換表面上(如: 鰭片)，主要是避免邊界層產生分離及降低摩擦力；其優點除了具有上述所言之一般鰭片的熱增強特性外，亦有較小的壓降；本研究係於具圓型管矩形鰭片之熱交換器，以對齊式( in-line )排列與交錯式(staggered)排列之鰭管式熱交換器為區分，於其鰭片上裝設渦流產生器，區分為VG0~VG3等形式，其中，VG0是不具渦流產生器的最初形式，而VG1~VG3分別是展開30°、45°、60°擴散排列之波浪型渦流產生器，並以計算流體力學軟體模擬真實的使用狀況來分析整體的流場及熱液動效率；結果發現，在熱傳因子j（Colburn factor）方面，對齊式(in-lined)排列之矩形鰭管式熱交換器的熱增強現象中，VG2(45°)較VG1(30°)上升了18%，VG3(60°)較VG2(45°)上升了13%，而VG1(30°)則較無裝設者上升了38%，而在交錯式(staggered)排列之矩形鰭管式熱交換器中，VG2(45°)較VG1(30°)上升了20%，VG3(60°)較VG2(45°)上升了27%，而VG1(30°)則較無裝設者上升了26%；相對而言，摩擦因子f（friction factor）部分，相較於無裝設渦流產生器者，較無裝設者之對齊式VG1(30°)約增加24.6%，VG2(45°)增加至35.7%，VG3(60°)則增加至48.6%，增加最多，而交錯式的VG1(30°)則約增加26.3%，VG2(45°)則增加至40.3%，VG3(60°)則增加至53.3%，在面積縮減率（1-A/Aplain ）的部分，對齊式中的VG3(60°)最佳(26.8%縮減至20.2%)，而交錯式的則是VG2(45°)最佳(29.3%縮減至25.1%)。

Numerical analyses were carried out to study the 3-D heat transfer and flow in the rectangular 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. In addition, numerical simulation was performed by a 3-D turbulence analysis of the heat transfer and fluid flow. There were four model types for this research, including VG0 to VG3. VG0 was the initial type which without vortex generators, and VG1 to VG3 represented the span angle 30°, 45° and 60°. The numerical result indicated these effects were intensified as the span angle is increased. Furthermore, no matter the arrangement type (in-lined and staggered), the case of 60° span angle provided the best heat transfer and Colburn factor augmentation, of course, the pressure drop and friction factor higher than the other, In Colburn factor, the 60° span angle case (VG3) is higher than without vortex generator 53.1% at in-line, staggered is higher 56.8%; In friction factor, the 60° span angle case (VG3) is higher than without vortex generator 48.6% at in-line, staggered is higher 53.3%. A reduction in fin area of 26.8% may be obtained if vortex generators embedded fins are used at in-lined arrangement rectangular finned-tube heat exchangers, and staggered arrangement reduction in fin area is 29.3% ~25.1%

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