具渦流產生器型式的散熱鰭片之實驗分析

The Experimental Analysis of Heat Sinks with The Type of Vortex Generator

邱信豪(Hsin-Hao Chiu)

指導教授 ： 林育才

元智大學/工程學院/機械工程學系/碩士(2004年)

摘要

本論文是探討以渦流產生器為設計理念，自行開發接觸角為30及45度；inline及staggered的排列型式共四款的散熱鰭片。因為三角對翼的渦流產生器具有降低壓降但卻能提升熱傳性能的特性，希望在面積減小的情況下，能以縱向渦流的效應來增加熱傳性能。實驗部分可分三部份：（1）探討接觸角、鰭片的排列方式對熱對流係數及壓降的影響。結果發現接觸角30度且inline的排列方式的組合具有熱對流係數較大且壓降降低的特性。（2）探討沒有bypass、bypass 5 mm及bypass 10 mm的情況下對熱對流係數及壓降的影響。結果發現在bypass 5 mm的情況下inline 30度的型式壓降降低26%但熱對流係數卻只降低10%，顯示在熱對流係數及壓降的交互考量下或許有個最佳bypass空間可供探討。（3）將四種散熱鰭片和一般的plate fin及pin fin做比對。雖然三角對翼具有縱向渦流的效應，但在散熱面積不足的情況下，熱傳性能仍然沒有plate fin及pin fin佳。

關鍵字

渦流產生器 ； 散熱鰭片

並列摘要

This research has experimentally investigated the performance of four different self-design heat sinks. The shape of the heat sinks is triangular and two the fins are attached together to form a wedge shape. The inclined angles of the fins are 30 and 45 degrees with respect to the air flow direction and the arrangements of fins have also two types: in-line and staggered. The results show that the heat sinks with 30 degrees inclined and with the in-line arrangement have better heat transfer performance and the corresponding pressure drop is also smaller. As for the study of the bypass effect on the performance, it is found that the pressure drop decreases about 26% and the heat transfer coefficient also decreases 10% for the heat sink with the 30 degree fins and in-line arrangement for 5 mm bypass space above the heat sink. Though the newly designed heat sinks can induce the longitudinal vortex that would help the heat transfer on the fin surfaces, the performance of the self-designed heat sinks still worse than the traditional plate-fin and pin-fin heat sinks due to the much smaller heat transfer area.

並列關鍵字

Vortex Generator ； Plate Fin ； Pin Fin ； Heatsink

參考文獻

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