微尺度相变传热的关键问题

由于航天、信息、生物等高技术的发展,微尺度热物理问题得到了广泛的重视.作为一种 非常高效的能量转换方法,微尺度相变传热的研究远未成熟.本文对微尺度相变传热作了较 为系统的综述,论述了控制微尺度相变传热的准则数,分析了沸腾起始点、流型、压降、传 热系数、不稳定性、临界热流密度六大关键问题.建议从实验和理论两个方面对微尺度相变 传热进行深入的研究,以进一步理解其机理,为微蒸发器的设计、制造及运行提供科学依据 和指导.

KEY ISSUES RELATED TO MICROSCALE PHASE CHANGE HEAT TRANSFER

With the fast advancement of aeronautics, information, and biology technologies, microscale ther-mophysical issues have received a great attention. As an effective energy conversion method, the microscale phase change heat transfer is far from mature. The non-dimensional parameters commonly used in the microscale phase change heat transfer are discussed in this paper. A comprehensive review is given on the six key issues, including boiling incipience, flow pattern, pressure drop, heat transfer coefficient, flow instability, critical heat flux. Suggestions are made on the study of the microscale phase change heat transfer to enhance the basic understanding of the complicated phenomena from the experimental and theoretical point of view. Such understandings may be used as the guidelines for the design, manufacture, and operation of the micro evaporators.