數值模擬低瓦特虹吸熱管之影響因子的熱傳特性探討

Numerical Simulation of The Heat Transfer Characteristics of Low-Watts Thermosyphon Influence Factors

黃信衡(Hsin-Heng Huang)

指導教授 ： 李世鳴

淡江大學/工學院/航空太空工程學系碩士班/碩士(2014年)

https://doi.org/10.6846/TKU.2014.01004

摘要

本研究以數值模擬分析低瓦特虹吸熱管在不同影響因子；即真空度、填充率、展弦比與傾斜角於自然對流狀態下對於熱傳特性的影響。考慮於連續方程式及能量方程式中藉由添加質量與能量源項來模擬汽液兩相變化，數值求解方法中壓力-速度耦合使用 SIMPLE 算則求解，其離散選項中壓力項採取物體力加權(Body force weighted)，動量與體積比率則採用 QUICK 離散格式，能量方程對流項採用一階上風算則。數值模擬計算結果與實驗資料比較分析顯示本研究所採用之數值離散方法確實對於虹吸熱管物理機制及傳熱性能分析具有適用性，並利用田口方法分析發現真空度與填充率對熱阻值有較大的影響，而在真空度35 torr、填充率90%、展弦比9.8、傾斜角45度時會得到最佳的熱阻。

關鍵字

熱管 ； Thermosyphon ； 田口法 ； 真空度 ； 填充率 ； 展弦比 ； 傾斜角 ； 沸騰熱傳

並列摘要

This study used numerical simulation to analyze the influence of different factors, e.g. vacuum degree, fill ratio, aspect ratio and inclined angle, on the heat transfer characteristics of low-watt thermosyphon in natural convection. The mass and energy source terms were added in the continuity and energy equation to simulate the exchanges between vapor and liquid phases. The comparison analysis of computed result and experiment data showed that the numerical model used in this study is appropriate to the analysis of physical mechanism and heat transfer property of thermosyphon. And We find that the vacuum degree and the fill ratio has a greater impact on the thermal resistance when we use the Taguchi method. The best thermal resistance when the vacuum degree was 35 torr and the fill ratio was 90% and the aspect ratio was 9.8 and the inclined angle was 45 degree.

並列關鍵字

Heat pipe ； Thermosyphon ； Taguchi method ； Vacuum degree ； Fill ratio ； Aspect ratio ； Inclined angle ； Boiling heat transfer

參考文獻

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