發泡金屬散熱鰭片在自然對流條件下之熱傳性能

Abstract

本論文為以實驗方法探討在自然對流條件下發泡金屬應用於傳統散熱鰭片上之熱傳性能。實驗採用不同孔數率(PPI)與厚度的發泡銅，以燒結的方式固定在銅底板上製成發泡金屬散熱鰭片，本實驗主要測試散熱鰭片樣本有三組，並且探討鰭片在水平與垂直角度下的熱傳性能。 最後探討熱輻射效應，比較有無黑體漆對熱傳的影響。 第一組實驗在固定鰭片總厚度條件下，觀察三種不同發泡金屬厚度與孔數率樣本之熱傳性能。6＋4mm,50PPI樣本的熱傳係數最高，較10mm平板高約6.6%，再來是9＋1mm,50PPI，較10mm平板高約3.5%。 第二組實驗樣本為在底板表面洗溝槽，在溝槽內燒結1mm,50PPI的發泡銅，實驗參數為改變溝槽間隙寬度。不管在水平與垂直角度下，表面全發泡樣本的熱傳係數較高。 第三組實驗做相同底板燒結不同厚度與孔數率的發泡金屬實驗結果顯示，角度對熱傳性能的影響特別顯著，鰭片垂直縱向擺放與水平擺放有較高的熱傳係數，垂直橫向擺放的熱傳係數較低。

This thesis is an experimental investigation of the heat transfer performance of metal foam used in traditional heat sink under natural convection. Experiment use different PPI and thickness of the copper foam, sintering metal foam heat sink on copper base plate, and this experiment to test heat sink three groups of samples, and explore the fins in heat transfer performance of horizontal and vertical angles. Finally, we discuss the effect of heat radiation, and comparison with or without black body paint on the heat transfer. The first set of experiments fixed the fin thickness, observed the heat transfer performance of metal foam with three different thickness and PPI, 6+4 mm,50PPI sample has the highest heat transfer coefficient, heat transfer coefficient for 6+4 mm,50PPI sample is better than 10mm flat plate by 6.6%, again 9+1 mm,50PPI sample is better than 10mm flat plate by 3.5%. The second set of experiments sample has groove in the base plate surface, and sintering 1mm,50PPI copper foam in the groove, the experimental parameters is to change the width of the groove gap. Regardless of the horizontal and vertical angles, surface all metal foam sample has the highest heat transfer coefficient. The third set of experiments is sintering different thickness and PPI metal foam on the same base plate, experimental results show that the orientation is particularly significant on the heat transfer performance, vertical display-vertical fin, and horizontal have higher heat transfer coefficient, vertical display-horizontal fin has lower heat transfer coefficient.