成型加工對於熱管性能影響之探討

Study on the influence of forming process to heat pipe’s performance

沈志宏(Chih-Hung Shen)

指導教授 ： 李基禎 ； 郭鴻森

大同大學/工程學院/機械工程學系所/碩士(2007年)

摘要

中文摘要

熱管為一傳熱的介質，利用液、氣體間之相變化循環來達到傳遞熱的目的。目前已經廣泛地運用在電子散熱之中。本研究就是利用一系列的實驗，探討成型加工程式對熱管之影響，歸納出相關的經驗法則，以作為日後相關散熱模組設計時之參考。
構成熱管的外觀改變的工序步驟主要為折彎製程、壓合製程以及兩者的組合。本文主要探討的就是實驗在不同種類毛細組織的熱管(銅網、溝槽及燒結銅粉)及不同的外徑尺寸下(Ф4, Ф5及Ф6 )，各式熱管對於成型加工後傳熱效能變化，以求取各式熱管可以接受成型加工的最大極限。
評估熱管的傳熱效能高低主要的判別方式為最大熱通量。先透過實驗的步驟量測出最大熱傳量，再利用公式求取最大熱通量的數值，比較熱管在成型加工前後最大熱通量的變化，藉以整理出加工後則對於熱管效能衰退的影響，取得熱管外觀形變與傳熱效能間的連動影響。
對於不同毛細組織的熱管而言，銅網管可以接受較大的壓合厚度，Ф4, Ф5 及Ф6可以接受熱管厚度為2.0mm，溝槽及燒結銅粉結構則為2.5mm。但在折彎製程的比較上，溝槽及燒結銅粉卻能提供較小的折彎半徑(Rc)。此外熱管在折彎及壓合之複合製程下時，除了注意壓合的厚度與折彎的半徑對於熱管的影響外，還需另外考量折彎的角度(θ)，當θ小於90度時，熱管的傳熱效能亦會有明顯的衰退。

關鍵字

毛細組織 ； 最大熱通量 ； 熱管

並列摘要

ABSTRACT

Heat pipe use of liquid and vapor. Two phase flow heat transfer, has been exercised in electronic cooling since 90’s. The mean study of thesis is to find out the performance curve after heat pipe forming process. Tracking the decayed range of heat pipe by a series of the related experiments. Build up the experimental trend as an engineering reference for designing thermal module of electronic components.
The research is to focus on the effect of heat pipe forming process including flatting, bending and both . The influence of deform about different wick structure (mesh, groove and powder ) of heat pipe , and different diameter (Ф4, Ф5 and Ф6 ) heat pipe’s forming limits of performance are also analyzed.
In this study, three parameter of heat transfer is detected. They are ΔT (2 points temperature difference), Qmax (Maximum Heat Transfer) and Q” max (Maximum Heat Flux). Comparison of each result is carried to get the deformation effects on heat pipe before and after.
The result of experiment shows that the mesh structure will support better flatting limits, eachψ4, ψ5 andψ6 mesh pipe can press to 2.0 mm thickness, but groove and powder type just support 2.5 mm deformation. About the bending , the groove and powder type will tolerate the smaller bending radius (Rc) in each different heat pipe diameter on the contrary. When both two processes are applied on the performance will be decreased for bending angle (θ) less than 90 degree.

並列關鍵字

wick structure ； maximum heat transfer ； heat pipe

參考文獻

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