中文摘要：

对微重力条件下液封液桥（流体采用KF-96硅油和FC-70氟化物，桥高1．4～4毫米，内层直径2或3毫米，外层直径5毫米）和单层液桥（流体采用KF-96硅油，桥高1～1．6毫米，直径2毫米）内的热毛细对流进行了数值模拟，模拟条件与Maiima等的实验条件相同。从理论上证实了大温差条件下将出现振荡热毛细对流，确定了发生振荡的临界条件并与相关实验结果进行了对比，同时还计算了振荡频率。

英文摘要：

The physical and mathematical models of the Marangoni convection of KF-96 silicone oil and FC-70 fluorinart in an encapsulated liquid bridge （or two immiscible coaxial liquid columns） with either 2 or 3mm inner diameter and 5mm outer diameter as well as variable height （1.4~4mm） heated from the top wall and cooled at the bottom wall with an adiabatic free surface were established. To contrast to this model, the Marangoni convection of KF-96 silicone oil in a liquid bridge with 2mm diameter and variable height （1-1.6mm） was also studied at present. We conducted a series of unsteady two-dimensional numerical simulations. Simulation conditions correspond to those in the experiments of MajiMa and Kawamura （2001）. The simulation results with large Marangoni number （Ma） predict oscillatory flows under microgravity. The critical conditions for the onset oscillatory flow are determined and compared with the experimental results. Details of the flow and temperature fields are discussed. Oscillation frequencies are also obtained from numerical simulation.