本文選題：超薄微熱管　切入點：復合吸液芯　出處：《華南理工大學》2015年碩士論文　論文類型：學位論文

【摘要】：隨著微電子、光電子領域不斷朝著高性能化和高集成度的方向發(fā)展,電子芯片的功耗日益增加,特別是在電子設備整體結(jié)構輕薄化、緊湊化的發(fā)展趨勢下,電子元器件的散熱問題日益凸顯。微熱管作為一種高效相變傳熱元件,已被廣泛應用于解決眾多領域的熱問題。但要在結(jié)構緊湊的電子設備上利用微熱管散熱,,必須開發(fā)出厚度更薄、體積更小且傳熱性能良好的超薄微熱管。吸液芯結(jié)構是影響微熱管傳熱性能最關鍵的因素之一,本文探究了三種適用于超薄微熱管的復合吸液芯結(jié)構及其成形方法,包括了單弓形銅粉復合溝槽吸液芯、雙弓形銅粉復合溝槽吸液芯和絲網(wǎng)復合溝槽吸液芯。制定了復合吸液芯超薄微熱管的制造工藝路線,并確定了各工藝參數(shù)。本文實驗制作了三種復合吸液芯結(jié)構的超薄微熱管樣品;利用掃描電子顯微鏡對樣品的橫截面、縱切面進行觀測,觀察復合吸液芯的復合燒結(jié)狀態(tài)、擠壓狀態(tài)以及撕裂狀態(tài),探索壓扁工藝對吸液芯結(jié)構最終成形所造成的影響,并結(jié)合傳熱性能實驗結(jié)果分析吸液芯成形狀態(tài)對傳熱性能的影響。本文基于微熱管的傳熱極限理論推導各主要傳熱極限的計算方法,并通過代入復合吸液芯的結(jié)構參數(shù)以及工質(zhì)的物性參數(shù)計算出超薄微熱管主要傳熱極限的具體數(shù)值。發(fā)現(xiàn)三種復合吸液芯結(jié)構的超薄微熱管主要受毛細極限的限制,55°C工作溫度下,單弓形復合吸液芯結(jié)構樣品的傳熱極限為12.5W,雙弓形結(jié)構為15.4W,絲網(wǎng)結(jié)構為19.4W。本文搭建了實驗平臺,并對不同充液率下的三種復合吸液芯結(jié)構超薄微熱管進行穩(wěn)態(tài)性能和動態(tài)性能測試。先通過縱向?qū)Ρ?探索超薄微熱管的最佳充液率;再橫向?qū)Ρ炔煌盒窘Y(jié)構樣品的傳熱性能,然后對比超薄微熱管分別在正常工作下和燒干狀態(tài)下的啟動性能。通過紅外熱成像的手段探究超薄微熱管的均溫性能和吸液芯的毛細性能。實驗表明:單弓形銅粉復合與雙弓形銅粉復合結(jié)構的最佳充液率均為70%,絲網(wǎng)復合結(jié)構為80%,三種結(jié)構的傳熱極限功率分別為12 W、13 W和14 W,蒸發(fā)熱阻呈現(xiàn)先減少后增加的趨勢,而冷凝熱阻相對穩(wěn)定,基本維持在0.2 K/W以下。加熱功率較低時,超薄微熱管從啟動到其穩(wěn)定的時間大概為100秒;加熱功率較高時,從啟動到其溫度出現(xiàn)燒干的時間大概為80秒。超薄微熱管具有良好的均溫性能,雙弓形復合吸液芯的毛細性能最佳,絲網(wǎng)結(jié)構毛細性能最差。
[Abstract]:With the development of microelectronics and optoelectronics, the power consumption of electronic chips is increasing day by day, especially in the trend of thinning and compactness of the whole structure of electronic devices. The heat dissipation of electronic components is becoming more and more serious. As a kind of high efficiency phase change heat transfer element, microheat pipe, Has been widely used to solve thermal problems in many fields. But in order to use micro-heat pipes to dissipate heat on compact electronic devices, a thinner thickness must be developed. The structure of liquid absorbing core is one of the most important factors affecting the heat transfer performance of micro heat pipe. In this paper, three kinds of composite absorbent core structures and their forming methods suitable for ultra-thin micro heat pipe are studied. Including single bow copper powder composite groove suction core, double bow copper powder composite groove suction core and wire mesh composite groove suction core. In this paper, three kinds of ultra-thin micro-heat pipe samples with composite absorbent core structure are experimentally made, the cross section and longitudinal section of the sample are observed by scanning electron microscope, and the composite sintering state of the composite absorbent core is observed. To explore the effect of flattening process on the final forming of sucking core structure under extrusion and tearing conditions. Combined with the experimental results of heat transfer performance, the influence of the forming state of liquid absorbing core on the heat transfer performance is analyzed. Based on the heat transfer limit theory of micro-heat pipe, the calculation methods of each main heat transfer limit are deduced. The main heat transfer limit of ultra-thin micro-heat pipe is calculated by adding the structure parameters of composite absorbent core and the physical property parameter of working fluid. It is found that three kinds of ultra-thin micro-heat pipe with composite liquid absorbing core structure are mainly limited by capillary limit. At the operating temperature of 55 擄C, The heat transfer limit of the single arch composite absorbent core structure is 12.5 W, the double arch structure is 15.4W, and the wire mesh structure is 19.4W. the experimental platform is set up in this paper. The steady-state and dynamic properties of three kinds of ultra-thin micro-heat pipes with different liquid-absorbing core structures were tested. Firstly, the optimum liquid-filled rate of ultra-thin micro-heat pipes was explored by longitudinal comparison. Then the heat transfer performance of different absorbent core structure samples is compared laterally. Then, the starting performance of ultra-thin micro-heat pipe under normal operation and burning dry state was compared. The average temperature performance of ultra-thin micro-heat pipe and the capillary property of absorbent core were investigated by infrared thermal imaging. The results showed that: single bow copper. The optimum liquid-filled ratio of powder composite structure and double bow copper powder composite structure is both 70 and 80, and the heat transfer limit power of the three structures is 12 W / 13 W and 14 W respectively. The evaporation thermal resistance decreases first and then increases. However, the condensation thermal resistance is relatively stable, basically below 0.2 K / W. when the heating power is low, the time from starting to stabilizing the superthin micro-heat pipe is about 100 seconds, and when the heating power is high, The time from starting to drying at the temperature is about 80 seconds. The ultra-thin micro-heat pipe has good homogeneous temperature performance, the capillary property of double-arch composite absorbent core is the best, and the capillary property of wire mesh structure is the worst.
【學位授予單位】：華南理工大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN605

【參考文獻】

相關期刊論文 前5條

1 張麗春,葛新石,馬同澤,張正芳;微槽平板熱管傳熱性能的實驗研究[J];工程熱物理學報;2003年03期

2 劉鶴青;;金屬絲編織密紋網(wǎng)的孔隙率[J];過濾與分離;2007年04期

3 李勇;湯勇;肖博武;李西兵;曾志新;;銅熱管內(nèi)壁微溝槽的高速充液旋壓加工[J];華南理工大學學報(自然科學版);2007年03期

4 蔣朝勇;夏侯國偉;;新型微型平板熱管的傳熱性能[J];長沙理工大學學報(自然科學版);2009年01期

5 過增元;國際傳熱研究前沿──微細尺度傳熱[J];力學進展;2000年01期

相關碩士學位論文 前2條

1 何恒飛;壓扁型超薄燒結(jié)式微熱管制造方法及性能分析[D];華南理工大學;2014年

2 侯亭波;面向大功率LED水冷散熱的微型換熱器設計及性能分析[D];華南理工大學;2014年

，

本文編號：1644055