臺灣博碩士論文加值系統

隨著先進電子設備散熱需求的增加，雙相冷卻技術展示其高效且良好的散熱效果。本研究旨在發展雙相流幫浦循環冷卻系統的數值模擬技術，使用OpenFOAM-v2206的六方程歐拉雙相流數值模型並結合壁面沸騰模型，以模擬流體沸騰相變化的複雜過程。該模型加入了耦合氣液兩相的動量交換項，考慮了因兩相之間密度、相對速度等差異所造成的橫向剪力運動。數值結果顯示，相較於SIMPLE，PIMPLE之溫度變化曲線更接近實驗值。接下來對不同鰭片數量的雙相流幫浦循環冷卻系統進行數值分析，數值結果顯示，散熱板能有效帶走晶片產生的熱量並提高晶片溫度的均勻性。最後將數值結果與實驗值進行比對，數值結果已呈現與實驗數據相符的趨勢。

With the increasing demand for cooling advanced electronic devices, two-phase mechanically pumped loop has demonstrated its high efficiency and excellent cooling performance. This study aims to develop a numerical simulation for two-phase mechanically pumped loop. Utilizing the six-equation Eulerian two-fluid model in OpenFOAM-v2206, coupled with a wall boiling model, to simulate the complex process of fluid boiling and phase change. The model incorporates the momentum exchange term between the gas and liquid phases to account for differences in density and relative velocity. Numerical results show that the temperature variation curve obtained using the PIMPLE algorithm is closer to the experimental values compared to the SIMPLE algorithm. Subsequently, a numerical analysis of two-phase pumped loop cooling systems with different numbers of fins was conducted. The results indicate that the cooling plates effectively dissipate the heat generated by the chips and improve the temperature uniformity of the chips. Finally, the numerical results were compared with experimental data and the numerical results showed a trend consistent with the experimental data.

符號表 IV
命名法 IV
縮寫 VIII
上標 VIII
下標 VIII
圖目錄 X
表目錄 XII
一、緒論 1
1.1 研究背景 1
1.2文獻回顧 3
1.2.1. 兩相流文獻回顧 3
1.2.2. 壁面沸騰數值方法文獻回顧 4
1.2.3. 兩相流幫浦循環冷卻系統文獻回顧 6
1.3 研究目的 9
二、研究方法 10
2.1 統御方程式 10
2.2. Mixture k-ε紊流模型 12
2.3. 動量交換模型 14
2.3.1. 阻力 (Drag force) 15
2.3.2. 升力 (Lift force) 16
2.3.3. 壁面潤滑力 (Wall lubrication force) 16
2.3.4. 紊流擴散力 (Turbulent dispersion force) 17
2.3.5. 虛擬質量力 (Virtual mass force) 18
2.4. 熱傳和質傳模型 18
2.4.1. 熱傳模型 18
2.4.2. 質傳模型 19
2.5. 熱物理性模型(Thermophysical models) 20
2.5.2. 狀態方程式(Equation of state) 21
2.6. 壁面沸騰模型 21
2.6.1. 氣泡脫離壁面的直徑( Bubble departure diameter ) 23
2.6.2. 氣泡成核位點密度( Nucleation site density ) 24
2.6.3. 氣泡脫離壁面的頻率( Bubble departure frequency ) 24
2.7 數值方法 24
2.7.1 SIMPLE方法 25
2.7.2 PISO方法 28
2.7.3 PIMPLE方法 30
三、模擬與分析 33
3.1 不同數值方法比較 33
3.1.1. 實驗架構 33
3.1.2. 計算域描述 35
3.1.3. 冷卻液參數特性 38
3.1.4. 數值結果與分析 39
3.2 鰭片數量對兩相流幫浦循環散熱系統之分析 43
3.2.1. 實驗架構 43
3.2.2. 計算域描述 47
3.2.3. 冷卻液參數特性 50
3.2.4. 數值結果與分析 51
3.3 兩相流幫浦循環散熱系統之應用 62
3.3.1. 實驗架構 62
3.3.2. 計算域描述 67
3.3.3. 數值結果與分析 70
四、結論 72
參考資料 75
附錄 80

圖目錄
圖1. SIMPLE方法流程圖。 25
圖2. SIMPLE（Semi-Implicit Method for Pressure-Linked Equations）方法。 28
圖3. PISO方法流程圖。 29
圖4. PISO（Pressure-Implicit with Splitting of Operators）方法。 30
圖5. PIMPLE方法流程圖。 31
圖6. PIMPLE（PISO-SIMPLE Coupled with a SIMPLE Corrector）方法。 32
圖7. 兩相浸沒式冷卻實驗架構示意圖。 34
圖8. 熱源構造示意圖。 35
圖9. 兩相流沉浸式冷卻系統模擬計算域示意圖。 36
圖10. 兩相流沉浸式冷卻系統模擬計算域網格圖。 36
圖11. 流體量測點(Ta)和熱源表面中心溫度(Tcase)的量測點位置圖。 37
圖12. 流體量測點(Ta))相對位置示意圖。 38
圖13. Tcase在不同數值方法下和實驗溫度比較圖。 40
圖14. 不同數值方法模擬結果和實驗值在P1的溫度比較。 41
圖15. 不同數值方法模擬結果和實驗值在P4的溫度比較。 42
圖16. 不同數值方法模擬結果和實驗值在P7的溫度比較。 42
圖17. 測試例實驗構造示意圖。 44
圖18. 測試例實驗構造側視圖。 44
圖19. 測試例實驗構造上視圖。 45
圖20. 測試例流體觀測點Tinlet和Toutlet、Tcase觀測點及9點固體溫度觀測點位置示意圖。 46
圖21. 測試例GPU熱源內部9個點及Base冷板底板內部9個點的觀測點相對位置圖。 46
圖22. 測試例模擬計算域示意圖。 48
圖23. 測試例三維網格圖。 49
圖24. 測試例6個鰭片1.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 53
圖25. 測試例6個鰭片0.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 53
圖26. 測試例12個鰭片1.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 54
圖27. 測試例12個鰭片0.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 55
圖28. 測試例24個鰭片1.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 56
圖29. 測試例24個鰭片0.5LPM在Base固體內部第1到第9點與Tcase溫度隨時間的變化圖。 56
圖30. 測試例不同鰭片數在不同流速下Tcase溫度隨時間變化圖。 57
圖31. 測試例不同鰭片數在不同流速情況下入口及出口的氣體體積率隨時間變化圖。 58
圖32. 熱安全評估。 61
圖33. 完整實驗構造示意圖。 63
圖34. 完整實驗雙熱源構造示意圖。 63
圖35. 完整實驗鰭片構造示意圖。 64
圖36. 完整模擬構造側視圖。 65
圖37. 完整模擬上視圖。 65
圖38. 流體觀測點Tinlet和Toutlet、Tcase觀測點及9點固體溫度觀測點位置示意圖。 66
圖39. GPU和CPU內部9個點位置圖。 67
圖40. 完整模擬初步計算域示意圖。 69
圖41. 完整模擬初步計算域示意圖。 69
圖42. 完整模擬初步計算域側視圖。 69
圖43. 完整模擬初步計算域示意圖前視圖。 70
圖44. GPU固體第1到第9點與TcaseGPU溫度隨時間的變化圖。 71
圖45. CPU固體第1到第9點與TcaseCPU溫度隨時間的變化圖。 71

表目錄
表一 本研究所使用之Thermophysical models 20
表二 熱源裝置尺寸和相關參數。 37
表三 FL-50在25℃時的特性。 39
表四 測試例實驗數據。 47
表五 測試例模擬尺寸。 49
表六 測試例初始條件。 50
表七 R1234yf冷媒相關參數特性。 51
表八 完整模擬尺寸。 68

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