三維流道中載裝有間隔凸塊熱源模組之共軛熱傳特性及效能提升之研究

Conjugate Heat Transfer Characteristics and Performance Enhancement of Discrete Block Heat Source Module in a Rectangular Channel

詹智航(Zhi-Hang Zhan)

指導教授 ： 蔡永利

國立虎尾科技大學/工程學院/航空與電子科技研究所/碩士(2011年)

https://doi.org/10.6827/NFU.2011.00082

摘要

本研究旨在針對三維流道中載裝有間隔凸塊熱源模組之系統，探討其傳導—強制對流共軛熱傳特性及散熱性能提升。首先，探討各類擋板與不同發熱凸塊高度對三維流道中流體流動、溫度分佈及間隔凸塊熱源模組之熱傳特性的影響；其次，探討不同熱傳導係數對間隔凸塊熱源模組之共軛熱傳特性的效應；最後，探討不同雷諾數對間隔凸塊熱源模組的冷卻效能增進。
本研究係以數值方法進行嚴謹的模擬，另外，為驗證數值模擬的正確性，本研究建置實驗系統來量測熱源模組之凸塊熱源表面溫度，比較實驗數據與數值模擬結果，發現其相對誤差介於10 - 20%。
依據本研究所探討之參數，當Re = 600、Bh = 0.25、7.1 ≦ Bx ≦ 8.4、平板型擋板且15° ≦ α ≦ 90°、V型擋板且30° ≦ β ≦ 180°、Hh = 0.125、Khf = 1000和Kpf = 100時，比較各類擋板對於熱源模組熱點溫度的影響，結果顯示，40°傾斜擋板能比其他擋板最多可多增加約11%的降溫效果；當0.2 ≦ Bh ≦ 0.35時，比較平板型擋板之擋板高度與擋板安裝位置對熱源模組的影響，結果顯示，擋板愈高其模組熱點溫度降溫效果愈顯著及擋板愈高其擋板較佳安裝位置皆需向前移，垂直擋板降低熱點溫度最佳可達45.6%，而40°傾斜擋板更可降低熱點溫度最佳可達57.5%，且40°傾斜擋板比垂直擋板有較小的壓力降比及較佳的效益，其最佳效益達1.66倍；當0.025 ≦ Hh ≦ 0.225時，比較平板型擋板在不同發熱凸塊高度對熱源模組的影響，結果顯示，發熱凸塊過高會阻礙40°傾斜擋板的縱向渦漩效應，進而降低傾斜擋板的熱傳增進效果；另外，當200 ≦ Re ≦ 1000時，比較平板型擋板在不同雷諾數對熱源模組的影響，結果顯示，雷諾數愈大，平板型擋板造成的壓力降比與效益愈高，但40°傾斜擋板的壓力降比增加趨勢較為平緩，以及有顯著的效益提升。

關鍵字

熱源模組 ； 擋板 ； 縱向渦漩 ； 熱傳增進 ； 數值模擬 ； 實驗量測

並列摘要

This study aims to investigate the conjugate conduction–forced convective heat transfer characteristics and cooling performance enhancement for a discrete block heat source module in a three dimensional channel.
First, the influences of baffle arrangements and different heat source heights on the fluid flow, temperature distribution and heat transfer for a discrete block heat source module in a three dimensional channel are rigorously studied. Second, the effects of different thermal conductivity on conjugate heat transfer characteristics for the module are examined. Finally, the influences of Reynolds number on cooling performance for the module are investigated.
The numerical simulation is rigorously performed in this study. In addition, An experimental system is set up to verify the results of numerical simulation. The difference in surface temperature of block heat source between the numerical and experimental data is in the range of 10 - 20%.
Based on the ranges of incestigated parameters for Re = 600, Bh = 0.25, 7.1 ≦ Bx ≦ 8.4, plate type baffle with 15° ≦ α ≦ 90°, V type baffle with 30° ≦ β ≦ 180°, Hh = 0.125, Khf = 1000 and Kpf = 100, the results show that the reduction in hot spot temperature of heat source module for the situation with 40° inclined baffle can be 11% larger than other arrangement of baffle.
When 0.2 ≦ Bh ≦ 0.35, the results show that the optimum position of baffle installation should locate more upstream for large baffle height and the cooling performance is better for large baffle height. The optimum position of baffle installation for 40° inclined baffle is in front of vertical baffle. The hot spot temperature can be reduced by 47.3% for vertical baffle and 57.6% for 40° inclined baffle. In addition, the pressure drop is smaller and enhancement efficiency of baffle is higher for the 40° inclined baffle.
When 0.025 ≦ Hh ≦ 0.225, the block heat source height would weaken the longitudinal vortices and reduce the heat transfer enhancement for larger Hh.
When 200 ≦ Re ≦ 1000, the results show that both the heat transfer characteristics and penalty of pressure drop owing to baffle installation increase with Reynolds number. Furthermore, the pressure drop is smallest and enhancement efficiency of baffle is highest for 40° incline baffle.

並列關鍵字

heat source module ； baffle ； longitudinal vortex ； heat transfer enhancement ； simulation ； experiment

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