具有表面蒸发的液层内热毛细对流过程广泛存在于工业生产和日常生活中，其表面蒸发及其引起的界面温度跳跃对液层内热毛细对流的影响及其复杂，机理尚不清楚。本项目以环形液池内工质在自身低压蒸汽环境下蒸发时的热毛细对流为研究对象、围绕“表面蒸发-界面温度跳跃-热毛细对流耦合机制”关键科学问题，采用实验观测和数值模拟相结合的方法开展系统而深入的研究。首先，确定热毛细对流对蒸发速率的影响规律，获取蒸发速率计算关联式；然后，分析表面蒸发速率和热毛细对流对界面温度跳跃的影响，认知温度跳跃物理本质；最后，确定具有表面蒸发液层内热毛细对流失稳临界条件及影响因素，探索不同蒸发条件下流动失稳后流型演变规律，获取流型演变图谱，揭示表面蒸发-界面温度跳跃-热毛细对流耦合的物理机制。本研究可进一步拓展热毛细对流研究领域，丰富和发展界面蒸发热质传输与流动耦合理论，并有望在考虑蒸发效应时热毛细对流稳定性方面取得创新性成果。

Thermocapillary convection in the liquid layer with surface evaporation exists widely in industrial production and daily life. Surface evaporation and the interfacial temperature jump caused by evaporation have extremely complicated influence on thermocapillary convection in the liquid layer, and the influence mechanism is still unclear so far. Aiming at the key scientific problem ‘the coupled mechanism among surface evaporation, interfacial temperature jump and thermocapillary convection’, this project studies systematically and thoroughly thermocapillary convection when the working fluid evaporates in the low pressure steam environment in the annular pools by using experimental observations and numerical simulations. First, determine the effect of thermocapillary convection in the annular pools on the evaporation mass flux, and obtain the evaporation flux correlation based on the experimental data. Then, analyze the effects of the surface evaporation flux and thermocapillary convection on the interfacial temperature jump, and cognize its physical nature. Finally, determine emphatically critical conditions of the flow destabilization for thermocapillary convection with surface evaporation in the annular pools, explore the flow bifurcation series under the different evaporation conditions, map the flow pattern transition diagrams and clarify the physical mechanism of the coupling effect among surface evaporation, interfacial temperature jump and thermocapillary convection. This study is very important to further expand the research field on thermocapillary convection, enrich and develop the coupled theory between the interfacial heat and mass transfer and the flow, and be expected to obtain some innovative achievements on thermocapillary convection with surface evaporation in the annular pools.