以動態溫度追踨法量測熱管最大熱傳量之實驗設計

The Experimental Design for the Qmax Measurement by Dynamic Temperature-Tracing Method

黃彥銘(Yen-Ming Huang)

指導教授 ： 林唯耕

國立清華大學/原子科學院/工程與系統科學系/碩士(2006年)

摘要

本篇論文主要是針對電子構裝散熱中之熱管元件進行了熱傳性能測試。利用熱管傳統標準測試法和動態溫度追蹤法(Dynamic-Temperature-Tracing Method)，比較二方法的熱管最大熱傳量和理論模擬彼此之間的差異性。在進行實驗之前，我們在蒸發部設置了十二個溫度點，以校正熱管的蒸發部並訂定實驗規範，以確保之後的實驗都是在同樣的條件下測試，經理論和實驗的印證，蒸發部可用多源非等加熱功率的模式，在各加熱功率時，其軸向溫度皆可保持在1℃內，徑向溫度則在2℃內，均勻地對熱管加熱。利用傳統標準測試法所測得之熱管最大熱傳量和理論模擬的誤差在10%以內，而動態溫度追踨法則在15%以內。利用動態溫度追踨法量測的結果顯示：冷凝部長度為60mm，冷凝水溫16℃，測試時間為5分的實驗誤差最低；冷凝部長度為40mm，冷凝部水溫11℃，測試時間為5分的實驗誤差最低；冷凝部長度為30mm，冷凝水溫11℃，測試時間為2分的實驗誤差最低，由上數據可歸納出，隨冷凝部長度的縮短，降低冷凝部水溫可提高實驗的準確性。且當冷凝部水溫降低，絕熱部溫度也會隨之降低，進而降低最大熱傳量，這樣的趨勢，有助於減少測試時所取的加熱瓦數，利於縮短實驗時間。此外，動態溫度追踨法的測試時間由5分鐘縮短至2分鐘平均只會增加5%的誤差，所以可以在維持實驗結果正確性的前提下，縮短測試時間為2分鐘。

關鍵字

熱管 ； 最大熱傳量 ； 燒結 ； 動態溫度追蹤

並列摘要

The purpose of the thesis is to test the heat pipe maximum heat transfer rate (Qmax) of the electronics cooling system. Two test methods were compared with each other which were Traditional Standard Test Method and Dynamic-Temperature-Tracing Method (D.T.T.). A sensitivity study was also achieved by this thesis. In order to maintain axial temperature difference less than 10C and radial temperature difference less than 20C, a non-uniform power load was introduced into the evaporator. The non-uniform power load can let the heat homogeneously flow into the evaporator. The error of Qmax between Traditional Standard Test Method and Simulation result is under 10％ , and the error of Qmax between D.T.T Method and Simulation is under 15％. The results of D.T.T. show that in the same test period, when the condenser length is decreasing, then reduce the cooling water temperature would increase the accuracy. The lower temperature of the cooling water was implied a lower adiabatic temperature, then the Qmax was decreasing too and result in the decreasing of the test period. In addition, the test time of D.T.T. method can only increase 5% error equally by 5 minutes reductions to 2 minutes. Therefore, under the maintenance experiment result accuracy, the test time could reduce to 2 minutes.

並列關鍵字

Heat Pipe ； Heat Dissipate ； Sinter ； Dynamic Tracing

參考文獻

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