堆疊型散熱鰭片在強制對流下之壓降與熱傳分析

Experimental Investigation of Pressure and Heat Transfer Performance of the Stack Heat Sinks under Forced Convection

鍾志豪(Jhih-hao Jhong)

指導教授 ： 林育才

元智大學/工程學院/機械工程學系/碩士(2007年)

https://doi.org/10.6838/YZU.2007.00245

摘要

本論文為研究堆疊型散熱鳍片的散熱性能以及壓降，由於之前的研究顯示以百葉窗型鳍片的性能為最佳，因此本論文將以渦流產生器套入此類鳍片之中，針對不同三角翼大小，以及不同的樣式搭配，再配合不同鰭片間距，以實驗量測渦流產生器對鰭片造成的壓降和熱傳的影響，最後並證明渦流產生器不但可有效的增加熱傳量，更能比百葉窗型省的壓降更小。之後延續半渦流、半平板在低間距為最佳設計的結果，再進一步為低間距(1mm)設計各種不同形式的樣品，以創造出更強大的渦流，最後使用VG1散熱評價，探討各鳍片的性能。研究結果顯示半渦流、半平板設計在間距1mm和1.85mm時分別能比平板減少7%與30%的散熱面積。

關鍵字

堆疊型散熱鰭片 ； 渦流產生器 ； 平板 ； 百葉窗 ； 三角翼

並列摘要

The thermal performance and pressure drop of the stack heat sinks with vortex generators are presented in this study. Effects of the sizes and arrangements of triangle wings, fin pitches on the pressure drop and thermal performance of the heat sinks are experimentally investigated in a wind tunnel. It is found that having vortex generators can sufficiently improve the thermal performance and reduce the pressure drop compared with the louvered heat sinks with the same fin pitch. For low pitches, the stack heat sink with vortex-generators on the first half fins has better performance than other designs. To enhance the thermal performance by induced stronger vortexes, more heat sink designs with a pitch of 1 mm are proposed and tested. To evaluate different designs of heat sinks, their performance are compared by using VG1 criteria. For the heat sinks having vortex-generators on the first half fins with pitches of 1 mm and 1.85 mm, their heat transfer areas can be reduced by 7% and 30% compared with the corresponding plate-fin heat sinks.

並列關鍵字

Stack Heat Sinks ； vortex generators ； plate ； louver ； triangle wings

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