摘要随着电子元器件高度集成化、固体激光器功率增强,高热流密度散热问题显得越来越重要。喷雾冷却具有高热流密度的冷却能力和严格的温度控制能力,在电子元器件和固体激光器散热方面具有广阔的应用前景。 理论上推导了喷雾冷却五种换热方式的数学模型,并分析得出强化喷雾冷却换热的途径,为实验分析奠定了基础。 搭建了闭式循环喷雾冷却系统,以 R134a 为冷却工质,固定加热功率,即热流密度一定,在不同质量流量下,进行了一系列实验。通过热电偶读数,计算出相应条件下的表面温度、换热系数、冷却效率和Nu数。实验研究了质量流量和工质进口温度对喷雾冷却换热性能的影响,并分析了冷却效率和Nu数的影响因素。61025
毕业论文关键词 喷雾冷却 热流密度 换热系数
Title the research of spray cooling
Abstract With the rapid development of the integration electronic components, the power of solid-state lasers is increasingly growing, high rate heat flux removal of high power devices become more and more important. Compared with the traditional cooling methods, with the advantages of high heat flux capacity and strict control of temperature, spray cooling will have a broad application prospect in high heat flux removal. Theoretically the five kinds of spray cooling heat transfer mathematical model,and analyze the methods to strengthen the capacity of heat exchange. The work laid the foundation for the analysis of experiment. Build a closed cycle spray cooling system that R134a is the refrigerant. Fixed heating power,that is to do a series of experiments at the same heat flux. In the meantime, change the mass flow. By reading the thermocouple, calculate the surface temperature, the heat transfer coefficient, spray cooling efficiency and Nusselt number. Effects of mass flow rate and the refrigerant inlet temperature on spray cooling heat transfer performance is studied by experiments, and analyze the influencing factors of cooling efficiency and Nusselt number.
Keywords Spray cooling Heat flux Heat transfer coefficient
目次
1 绪论 1
1.1课题研究背景 1
1.2喷雾相变冷却机理 1
1.3.1喷雾相变冷却换热主要影响因素 3
1.3.2喷雾冷却的最新应用及测量技术 5
1.4本文的主要工作 5
2 喷雾冷却换热理论数学模型 . 6
2.1液滴撞击表面换热 6
2.2核态沸腾换热 7
2.3液滴蒸发换热 8
2.4空气对流换热 9
2.5辐射换热 9
2.6本章小结 . 10
3 喷雾冷却实验系统 11
3.1闭式循环喷雾冷却系统 . 11
3.2冷却工质的选择 . 12
3.3实验设备介绍 . 13
3.3.1喷嘴 . 13
3.3.2低温恒温槽 . 14
3.3.3 K型热电偶 . 15
3.3.4齿轮泵 . 16
3.3.5模拟热源 . 16
3.4实验步骤 . 17
3.5本章小结 . 18
4 闭式循环喷雾冷却系统的实验研究 19
4.1实验数据及计算 . 19 喷雾冷却技术研究:http://www.youerw.com/wuli/lunwen_66630.html