毛細結構幾何參數與真空度對熱管最大熱傳量之實驗 與HPPS理論之比對

Effect of heat pipe wick geometric parameters and vacuum pressure to the heat transfer rate of heat pipe and comparison of the HPPS theoretical model

高啟豪(Kao,Chi Hao)

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(2016年)

摘要

熱管的性能不僅取決於幾何參數，如壁厚、管材料，還有工作流體之熱力性能，如潛熱，蒸汽壓力，粘度。熱管之操作參數壓力和真空也是很重要之影響性能之參數。本研究初步建立包括毛細結構的滲透度(Permeability),最大毛細半徑(Maximum Capillary Diameter)與孔隙比(Porosity)及熱管最大熱傳量之量測。此實驗數據將與HPPS軟體做比對。HPPS(Heat pipe program software熱管性能模擬軟體)是由台灣清華大學的先進冷卻散熱實驗室所發展的以毛細理論預測熱管性能之軟體，其設定參數包括輸入不同熱管材質、不同工作流體、真空度、填充量以及操作的溫度等，並計算出該熱管之最大熱傳量，以探討各項參數對性能影響的重要性。
本實驗量測H廠商與C廠商之毛細結構幾何參數，其滲透度為2.57×10-13m2、0.327×10-13m2，最大毛細半徑為8.08×10-6m、9.09×10-6m，孔隙比為0.559、0.621，本實驗室模擬散熱水平量測毛細結構之熱管最大熱傳量，以H廠商外徑6φ的銅粉之燒結毛細結構熱管比較實驗室自製的熱管，其工作流體為水，固定操作溫度50℃，填充量30%時，最大熱傳量為45W；H廠商生產的熱管在同樣條件下之最大熱傳量為25W。真空度從1torr到10-4torr時最大熱傳量從35W增加到45W。

關鍵字

熱管 ； 真空度 ； 最大熱傳量 ； 填充量

並列摘要

Performance of heat pipe not only depends on geometry, such as wall thickness, pipe material, but also the thermal properties of the working fluid, such as latent heat, vapor pressure, viscosity, pressure and vacuum. We develop a experiment for Permeability, Maximum Capillary Diameter, Porosity, and the maximum of heat transfer. These experimental data will compare with HPPS. HPPS (heat pipe performance Simulation program software) is a software made by the advanced cooling heat laboratory Taiwan Tsinghua University to predict heat pipe performance with capillary structure theory , and its parameters include various heat pipe materials, different working fluids, vacuum degree, filling volume and operating temperature setting. Maximum heat transfer in different condition such as vacuum different degrees, or filling volume can be measured by experiments. importance of each parameters can also be discussed.
Experiment for heat pipe’s wick geometric parameters of H company and C company. The Permeability of two company is 2.57×10-13m2、0.327×10-13m2 The Maximum Capillary Diameter of two company is 8.08×10-6m、9.09×10-6m The Porosity of two company is 0.559、0.621. Experiment the maximum of heat transfer with standard way, compare with 6φ sintered copper heat pipe of H company and the self made heat pipe. When the working fluid is water in 50℃ with filing volume 30% the maximum heat transfer is 45W; Under the same conditions the maximum heat transfer is 25W of H company. When vacuum from 1torr to 10-4torr, the maximum heat transfer will from 35W to 45W.

並列關鍵字

heat pipe ； the degree of vacuum ； the maximum heat transfer ； filling volume

參考文獻

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