Abstract: This paper reviewed the basic working principles of heat pipes and introduced seven types of heat pipes,including thermosyphons,reciprocating heat pipes,pulsating heat pipes,loop heat pipes,rotating heat pipes,micro-heat pipes and variable conductance heat pipes. The applications on the reliability of railway embankment,endurance of machine components,heat dissipation of integrated circuits and resolution of temperature measurement instruments were discussed. The wick structure and the development of composite structures increased permeability and capillary pressure. Material compatibility determines the lifespan of heat pipes and is a key issue to be considered in heat pipe design. Conventional heat pipe manufacturing methods of separately fabricating tubes and wicks were briefly reviewed and discussed. The trends of heat-pipe microminiaturization and structural integration demand more effective heat-pipe shapes and wick structures. A novel heat-pipe fabrication method based on the three dimensional (3D) printing was proposed. This method is able to achieve one-step forming of both the heat-pipe body and the wick structure and directly integrate a heat-pipe device into the structure where heat should be dissipated. As a result,more significant heat-transfer efficiencies and larger economic benefits can be accomplished.

Key words: heat pipe, wick structure, fabrication, heat conduction, phase change

摘要： 首先回顾了热管基本工作原理,随后分别简述了热管发展过程中衍生的热虹吸管、往复热管、脉动热管、回路热管、旋转热管、微型热管和可变导热管.列举了它们在提高铁路路基可靠性、延长机械零件寿命、强化集成电路散热和提高温度测量精度等方面的应用.着重阐述了热管核心吸液芯结构以及复合吸液芯的发展带来的渗透率和毛细力的提高.热管材料的相容性制约热管的使用寿命,相容性材料的选择亦是热管设计的重要内容.最后简述了热管传统加工制造方法,即管壳与吸液芯分开加工的方法.热管微型化发展和与服务对象的结合对热管形状和吸液芯结构多元化的要求不断提高.提出了基于三维打印的新型热管加工方法,此方法便于热管管体与吸液芯结构一次成型,并直接将管体与被散热体集成一体,从而达到以往难以实现的复杂散热效果和经济效益.三维打印技术的飞速发展有望为吸液芯结构的创新提供新的空间,同时为热管的应用提供一个更为广阔的市场.

关键词: 热管, 吸液芯, 加工制造, 热传导, 相变