Investigation and Analysis of the Capillary Heat Plate

近十幾年來，晶片的性能與運算速度不斷提升，除了傳統總發熱量(Total Power)的問題以外，新增加了由發熱量密度不均勻分佈所產生之熱點問題(Hotspot)。毛細熱板(Capillary Heat Plate)在操作時產生沸騰的機制，同時藉由蒸氣腔體(Vapor Chamber)的設計使熱量能迅速且均勻的擴散來達到散熱和均溫的效果。本研究針對毛細熱板設計一套完整的實驗方法，研究加熱功率、填充量、傾斜角度、熱源面積大小對於毛細熱板的性能影響，並建立理論模式，以提供未來對於毛細熱板進一步的分析與改善。實驗結果顯示，熱板熱阻會隨著加熱功率的增加而下降，最佳的充填量為3.31cc，約佔容器總體積的30%。過低的填充量會出現燒乾的現象，而充填量過高系統性能亦會變差。當毛細熱板垂直或顛倒放置時，依舊可正常操作。毛細熱板的等效熱傳導係數優於同尺寸的銅板，而毛細熱板的擴散熱阻(Spreading Resistance)可以比銅板降低約35%。毛細熱板散熱模組的性能在填充量為30%、加熱功率為180W時表現最佳，相較於同尺寸的銅板，總熱阻約低20%。In recent decades, performance of the chip and speed of operation are improving constantly, there is the problem of the hotspot produced by the non-uniform density of heat source newly besides the tradition problem of the total power have increased. The boiling mechanism appears within the capillary heat plate while operating, at the same time it can dissipate heat rapidly and also spread heat evenly to get the result of uniform temperature within the design of vapor chamber. In the paper there is a set of detailed experiment methods for investigation and analysis of the capillary heat plate. Study the influence on performance of the heating rate, fill ratio, angle of inclination, and heater area and set up theory models in order to offer the analysis and improvement of the capillary heat plate in the future. The experimental result shows that the thermal resistance will drop with increasing of heating rate and the best filling amount is 3.31cc, accounts for 30% of the total volume of the container. When the fill ratio is too low, the system inside will burn out. If the fill ratio is higher, the system performance will become bad. As the capillary heat plate is put vertical or upside down, it can still work normally. The heat-conduction coefficient of the capillary heat plate is superior to copper. The spreading resistance of the capillary heat plate is lower by about 35% than copper. When the fill ratio is 30% and the heating rate is 180W, the performance of the capillary heat plate will be best and compare with copper, the total resistance is lower about 20%.摘要..................................I ABSTRACT..............................II 目錄..................................III 表目錄................................VI 圖目錄................................VII 符號說明..............................X 第一章 緒論...........................1 1.1前言...............................1 1.2研究動機與目的.....................3 1.3文獻回顧...........................4 第二章 基本原理與理論模式.............8 2.1毛細結構基礎概念...................8 2.1.1 多孔隙表面沸騰機制..............8 2.1.2 毛細現象........................11 2.1.3 毛細構造等效熱傳導係數..........14 2.2 毛細熱板系統原理與限制............17 2.2.1 毛細熱板操作原理................17 2.2.2 毛細熱板操作極限................18 2.3 熱阻模型建立......................20 2.3.1 熱阻基本概念 ....................21 2.3.2 熱阻分析模式 ....................22 2.3.3 界面熱阻........................23 2.3.4 熱板熱阻........................25 2.3.5 對流熱阻........................27 第三章 實驗設備與研究方法.............38 3.1 實驗系統說明......................38 3.1.1 實驗系統........................38 3.1.3 實驗設備........................40 3.2 實驗參數..........................43 3.2.1 模擬發熱源之加熱功率............43 3.2.2 工作流體之填充量................44 3.2.3 毛細熱板之傾斜角度..............45 3.2.4 熱源面積大小 ....................45 3.3 實驗流程..........................46 3.4 熱損耗量測........................47 3.5 誤差分析..........................48 第四章 結果與討論.....................57 4.1 加熱功率對系統性能的影響..........57 4.1.1實驗結果描述.....................57 4.1.2結果討論.........................60 4.2 填充量對系統性能的影響............62 4.2.1實驗結果描述.....................63 4.2.2結果討論.........................64 4.3傾斜角度對系統性能的影響...........65 4.3.1實驗結果描述.....................66 4.3.2結果討論.........................68 4.4 熱源面積大小對系統性能的影響......71 4.4.1 實驗結果描述 ....................71 4.4.2 結果討論........................72 4.5 毛細熱板與銅板之比較..............73 4.6 實驗與理論之比較..................77 第五章 結論與建議.....................108 5.1 結論..............................108 5.2 建議..............................111 參考文獻..............................11