为了深入理解高温碱金属热管吸液芯内汽液相变的微观传热机理，本文采用接触线传热模型对不同碱金属工质(钾、钠、锂)的蒸发弯月面区域微观传热特性进行了研究。计算得到了钾、钠、锂在同一饱和汽相压力和壁面过热度下蒸发弯月面区域的液膜厚度、接触角、界面温度、热流密度分布等。研究结果表明，由于碱金属工质钾、钠、锂的导热系数远高于水，其微观传热特性与水显著不同；汽-液界面蒸发热阻是碱金属工质在三相接触线附近微观区域内主导的传热热阻，钾、钠、锂的微观传热性能依次增强；吸附液膜的厚度、表观接触角和液膜压力梯度均随着壁面过热度的增加而自适应调节，其中吸附液膜厚度降低，表观接触角增加、液膜压力梯度增加。在吸附液层区，分离压力占据主导地位，导致了非蒸发吸附液层的形成；在薄液膜区，分离压力和毛细压力的共同作用提供了补液所需的压力梯度；在本征弯月面区，汽液界面的曲率几乎维持不变，毛细压力占主导。

To elucidate the micro-scale heat transfer mechanisms of the liquid-vapor phase change process in the wick of the high-temperature alkali metal heat pipe, we investigate the micro-scale heat transfer characteristics at the evaporating meniscus region for different alkali metals including potassium, sodium, and lithium by the contact line heat transfer model in this work. Distributions of the liquid film thickness, contact angle, interface temperature, and heat flux at the evaporating meniscus region for different alkali metals are obtained under the same saturation vapor pressure and wall superheat. Our results show that due to the high thermal conductivity of alkali metals, contact line heat transfer characteristics of potassium, sodium, and lithium are quite different from those of water. For alkali metals, the heat transfer in the micro region near the three-phase contact line is dominated by the thermal resistance at the vapor-liquid interface. Among potassium, sodium and lithium, lithium has the highest micro-scale heat transfer performances. We demonstrate that the thickness of the non-evaporating liquid film, the apparent contact angle and the pressure gradient of the liquid film are self-tuned according to the wall superheat, and a higher superheat results in a thinner non-evaporating liquid film, larger apparent contact angle and larger pressure gradient. The adsorbed film region, where a non-evaporating liquid film is adsorbed on the wall, is dominated by the disjoining pressure. In the thin-film region, both disjoining pressure and the capillary pressure contribute to the total pressure difference that pumps the liquid from the intrinsic meniscus region. The curvature of the vapor-liquid interface remains constant, and the capillary pressure dominates in the intrinsic meniscus region.