電子構裝散熱鰭片之性能分析

THERMAL PERFORMANCE ANALYSIS OF HEAT SINK FOR ELECTRONIC PACKAGE

張乃建(Nai-Chien Chang)

指導教授 ： 林育才

元智大學/工程學院/機械工程學系/碩士(2002年)

摘要

本文旨在探討散熱鰭片的性能分析，以數值軟體來模擬各項參數對鰭片性能的影響，並以實驗作基本的驗證。
經由分析所得的數值解，發現高傳導係數的材料、增大鰭片尺寸、增加熱源面積與提高風速會使熱阻降低，而功率增加與進風溫度對熱阻值並無太大的影響，但都會提升晶片溫度。
而鰭片設計對熱阻的影響，可由模擬結果知道一直增加固定的間隔寬度會造成鰭片面積的減少進而提高熱阻，而在固定鰭片長的情形下，針狀式的鰭片會使熱阻大小相似，但如果是片狀設計的鰭片，其散熱效果就會因鰭片距熱源的遠近有不小的差異。另外發現當鰭片超過一定高度後就不會與外界做熱交換了，所以在設計時要注意鰭片的散熱有效高度。
最後將實驗的數據與數值解互相比較，發現兩者有誤差存在，但可藉由加強壓力與導熱膏兩方面來使實驗更接近數值結果。

關鍵字

散熱 ； 鰭片

並列摘要

Both numerical and experimental approached have been used to investigate the thermal performance of heat sinks for electronic packages. The effects of operating parameters include inlet air velocity and temperature, size and power of heat source, different geometries and material properties of heat sinks, etc. on the thermal resistance of heat sink have been studied. The numerical results are also compared to the corresponding experimental results.
The results show that the thermal resistance of heat sink will decrease with the increase of thermal conductivity of heat sink, size of heat sink, size of heat source and inlet air velocity. However, there is little effect of the power of heat source and inlet air temperature on the thermal resistance of heat sink. The highest temperature of the heat sink increases almost linearly with the increase of the power and the inlet air temperature.
The results also show that the increase of the gap size in a straight plate fin will reduce the size of heat sink and therefore will increase its thermal resistance. It is also found that the increase of the height of heat sink may not improve the thermal resistance.
Finally, the discrepancy between the numerical and experimental results may be due to the contact resistance between the heat source and the heat sink. The difference can be reduced by increase the pressure on the heat sink.

並列關鍵字

HASH(0xcb563a4)

參考文獻

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