Abstract:

The study of the effects of wettability and magnetic field on the liquid metal free surface film flow state is performed by numerical simulation and experiment. Firstly the effects of wettability on the film flow state are investigated by numerical simulations. The results show that the liquid metal film is easy to become rivulet flow and cannot cover the whole bottom surface when the wettability is poor, the rivulet flow is easily developed when the initial film thickness is small, it is more easily developed into rivulet when the destiny becomes smaller as the initial film thickness and other conditions are same. Secondly, the effects of magnetic field on the film flow are studied, it is indicated that the cover bottom surface of liquid metal film under the condition of strong magnetic field increases compared with the condition of no magnetic field when the wettability of liquid to channel is poor, and the strong magnetic field can suppress the turbulence of the film flow. In the end, the experimental results of the liquid metal film flow show that the film flow of GaInSn alloy is easily contracted into rivulet flow, which is coincident with the numerical results. Above results are valuable for the design of liquid first wall of magnetic fusion reactor.

Key words: Liquid first wall, Film flow, Wettability, Strong magnetic field, MHD flow.

摘要：

通过数值模拟及实验研究了润湿性及磁场对液态金属膜流流动状态的影响。首先，通过数值模拟研究了润湿性对膜流流动状态的影响。结果表明，当润湿性不好时，液态金属膜流容易发展为溪状流而不能完全覆盖底壁，入口膜厚较薄时更易发展为溪状流；在入口膜厚及其它情况相同时，密度越小越易发展为溪状流。其次，研究了磁场对膜流流动状态的影响。结果表明，槽道与流体润湿性不好时，有磁场情况下液态金属膜流覆盖底壁的区域较无磁场时增加，强磁场对膜流的湍流有抑制作用。最后，液态金属膜流实验结果表明，润湿性不好时，镓铟锡合金膜流容易收缩发展为溪状流，这与数值模拟的结果是一致的。上述研究结果对磁约束聚变堆液态第一壁的设计具有指导意义。

关键词: 液态第一壁, 膜流, 润湿性, 强磁场, MHD流动