热毛细对流的液桥几何位形及浮力效应

本文讨论重力对不同高度、直径比液桥的热毛细对流的影响。当液桥高度、直径比增大时,液桥中的等流函数线呈双涡结构,这种流动图样并不必然与热毛细振荡流相联系。在地面热毛细对流实验中模拟空间微重力情况,液桥高度需小于1.5mm。在微重力环境中,液桥内的流场和温度分布介于地面相同参数液桥的上部加热和下部加热两种结果之间。因此,可以用地面实验结果估计空间液桥的对流和热输运情况。

THE LIQUID BRIDGE CONFIGURATION AND EFFECTS OF BUOYANCY IN THERMOCAPILLARY CONVECTION

The effects of gravity and thermocapillary convection in the liquid bridge with different aspect ratio L/D are studied in the present paper. Two flow cells appear in the liquid bridge. If L/D is longer, however, the flow pattern is not necessarily associated with the thermocapillary oscillatory convection. In order to simulate the space microgravity situation on the ground laboratory, the height of the liquid bridge must be smaller than, for example, 1.5mm. The convection and thermal transportation in a liquid bridge in microgravify environment can be estimated according to the experimental results on the ground, for the distribution of flow field and temperature in microgravity environment is between the cases of upper rod heated and lower rod heated, respectively, on the ground.