论文总字数：25185字

摘 要

日益小型化的电子器件和设备的散热问题促使脉动热管（PHP）这种新型高效的传热元件得到越来越广泛的研究。本文针对丙酮-水混合工质脉动热管，在50％充液率，丙酮和水的体积配比分别为0.3：0.7，0.5：0.5，0.9：0.1时，加热功率从5W~230W时的传热性能实验结果，进行了热管的传热性能分析和对比，同时计算和分析了混合工质体积配比、传热功率对工质的传热流动参数，如饱和压力、干度、显热传热量、潜热传热量、质量流量和振荡流速的影响规律。在此基础进行了丙酮-水混合工质的热物性（饱和压力、单位温升工质显热传热量、单位温升工质潜热传热量）随工质温度变化的计算，分析了温度和体积配比对工质热物性的影响规律。

结果表明：对于50％充液率下三种体积配比的丙酮-水脉动热管，传热热阻随功率都增加呈现先快速降低到趋于平稳的变化，且功率小于100W时功率和配比对热管热阻的影响较大。功率小于200W之前，高丙酮份额（0.9：0.1）PHP的热阻最低；脉动热管传热主要靠显热传热，当功率从5W升到230W时，显热传热比率从99%最低降到80%，而潜热传热份额从1%升到20%左右；其中相同充液率和加热功率下，丙酮份额越大，潜热份额越高；工质的质量流量和流速随功率的增大先增加，达到最大流速后高位振荡再减小，其中丙酮份额越大，中小功率时的质量流量和流速越大，达到最大流量和流速时的功率也越小；当管内工质温升1℃，热管内丙酮-水混合工质的潜热随着工质温度的升高而增加，其中相同充液率和温度下，丙酮份额越高，潜热传热量越大。而显热传热量、总传热量都随着工质温度的增加而降低，其中相同充液率和温度下，丙酮份额越高，显热、总传热量越小。

关键字：脉动热管 传热特性 物性分析 丙酮-水双工质

Heat transfer performance of acetone/water pulsating heat pipe and its analysis of thermal properties

Abstract

With the miniaturization of electronic components and system,as well as continous increase in the power density,the pulsating heat pipe (PHP) plays an important role in the thermal management. In this study, Experiments of pulsating heat pipes (PHP)were conducted, with acetone/water binary mixtures at different ratios (0.3:0.7,0.5:0.5,0.9:0.2) under 50% filling ratios and heat inputs (5-230W).The experimental results were analyzed and compared with the heat transfer performance.meanwhile calculated and analyzed the effect of different ratios and heat input on the working fluid flow parameters,such as saturation pressure, dryness, sensible heat, latent heat , mass flow and velocity.Then, the effect of the temperature and different ratio on the thermal propertiesof the mixture of acetone/water, the influence of temperature and volume ratio on the thermal properties of the refrigerant is analyzed.

The results show that for the three ratio of acetone/water pulsating heat pipe filled with 50% ratio, The heat transfer thermal resistance decrease to the stability with the heat input ,and the thermal resistance of the heat pipe is greatly affected by The heat input and the ratio when the heat input is less than 100W. When the heat input is less than 200W,the high acetone share(0.9:0.1) of the PHP posses the lowest thermal resistance. The mainly heat transfer of pulsating heat pipe is sensible heat, When the heat input rise from 5W to 230W, the sensible heat transfer rate decrease from 99% to 80%, while the latent heat transfer share increase from 1% to 20%. The higher the acetone share, the higher the latent heat share when the filling rate and heat input are the same. The mass flow and the flow velocity of the mixture fluid first increase to the maximum flow velocity and then decrease with the increase of the heat input,which the The larger the acetone share, the higher the mass flow and the velocity and the smaller power when it achieves its maximum velocity. The latent heat

water increases with the increase of temperature when the temperature of working fluids rise 1 degree. The higher the acetone share, the higher the latent heat when the filling rate and the temperature of the working fluids are the same. While The sensible heat and total heat decrease with the increase of the temperature of mixture working fluids. Instead,the higher the acetone share, the less sensible heat and the total heat. when the filling rate and the temperature of the working fluids are the same.

Key words:Pulsating heat pipe; Heat transfer characteristics; physical property analysis; water-actone Two working fluids

目 录

摘要…………………………………………………………………………………I

ABSTRACT………………………………………………………………………II

第一章 绪论………………………………………………………………………1

1.1课题背景……………………………………………………………………1

1.2概述…………………………………………………………………………1

1.2.1 脉动热管介绍…………………………………………………………2

1.2.2 性能测试实验系统……………………………………………………2

1.3运行机理及主要影响因素…………………………………………………3

1.3.1充液率影响……………………………………………………………3

1.3.2工质影响………………………………………………………………4

1.3.3倾斜角的影响…………………………………………………………5

1.4国内外研究进展……………………………………………………………5

1.5混合工质特性研究现状……………………………………………………9

1.6本课题研究内容 …………………………………………………………11

第二章 丙酮-水脉动热管实验结果及分析………………………………12

2.1实验装置简介 ……………………………………………………………12

2.2实验处理的结果 …………………………………………………………13

2.3实验处理分析 ……………………………………………………………14

2.4流动传热性能分析 ………………………………………………………16

2.5随功率变化的各物性分析 ………………………………………………19

2.6本章小结 …………………………………………………………………22

第三章 丙酮-水物性分析……………………………………………………24

3.1丙酮和水工质的各物性参数 ……………………………………………24

3.2丙酮和水三种体积配比的各物性参数 …………………………………26

3.2.1计算方法分析 ………………………………………………………27

3.2.2 三种配比温升1℃各物性分析 ……………………………………27

3.3本章小结 …………………………………………………………………30

第四章 结论与展望 …………………………………………………………32

参考文献…………………………………………………………………………34

致谢………………………………………………………………………………36

第1章 绪论

1.1 课题背景

热管是一种具有极高导热性能的传热元件，近几十年得到了飞速发展。美国人Gaugler^[1]于1942 年提出了热管这一概念。他当时设想将热管应用于冷冻机，但是这种设想在当时并没有得到实现。20世纪70年代以来，由于宇宙航行对传热所提出的特殊要求，再加上热管能够很好的节约能源，这使得热管理论研究和工程应用得到飞速的发展。我国热管研究开始于1970年左右,1972年第一根钠热管运行成功,以后相继研制成功氨、水、钠、汞、连苯等各种介质的热管,并在应用上取得了一定的进展。1980年国内第一台实验性热管换热器运转成功^[2],各地相继出现各种不同类型的、不同温度范围的气—气热管换热器及气—液换热器,在工业余热回收方面发挥了良好的作用, 并积累了一定的使用经验。

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