摘要
本研究利用ANSYS Fluent針對高功率60W LED散熱鰭片模組進行熱流場分析，將原本的輻射狀散熱鰭片更改為螺旋狀鰭片，比較兩者在自然對流及強制對流下之散熱性能，並探討螺旋狀鰭片之曲率半徑與鰭片數量對散熱模組整體溫度之影響。 結果顯示在自然對流下，螺旋狀模組之散熱性能僅略高於輻射狀模組，但是有風扇之螺旋氣流吹向散熱模組時，螺旋狀模組之散熱性能明顯優於輻射狀模組。隨著螺旋狀模組之鰭片曲率半徑增加，散熱器及PCB溫度亦隨之上升，代表熱量無法散去而逐漸累積。鰭片散熱性能亦會因鰭片數之增加而提升，但是在鰭片數量超過30片後，繼續增加鰭片數反而會使散熱性能下降。另外，圓形散熱鰭片無論鰭片曲率半徑或數量多寡，大部份熱量皆累積於散熱器中央處 ，其原因為相較於鰭片外圍，鰭片中央處與空氣接觸之面積較小，因此鰭片表面與空氣進行熱交換之效能較差，且受到回流的影響，大部分流經鰭片中央處之氣流皆為已受熱之空氣，導致熱量更容易堆積於鰭片中央處。
並列摘要
This research investigated the temperature and flow fields of LED light bulbs by a CFD software (ANSYS-FLUENT). A 60W LED is used as the reference model for comparison. Some modified models with spiral fins were studied under free and forced convections. Various radiuses of curvature and numbers of fins were also studied and analyzed for heat dissipation performance. Results demonstrated that when cooled by the spiral airflow cooling module was the heat dissipation performance of the spiral module was obviously better than the radial module. While under natural convection, the cooling performance of the spiral module was only slightly better than that of radial module. For spiral module, as the curvature of fins increased, temperature of cooling model and PCB were both increased. The increased numbers of fins, which regulated the radius of curvature, increased the heat dissipation performance. However, when the number of fins greater than 30, the fins would be highly packed and would cause the cooling performance decreased. In addition, in both spiral and straight modules, most of the heat was accumulated in the central regions.