【摘要】 为了了解环形浅液池内热毛细对流的特征,利用有限容积法对外壁受热、内壁冷却、厚度为1 mm的环形浅液池内硅油的热毛细对流进行了三维数值模拟。结果表明,当Marangoni(Ma)数小于临界值时,随着Ma数的增加,内、外壁附近的温度梯度上升,稳定的二维轴对称流动的径向速率增加;超过临界Ma数后,流动转化为三维振荡对流,形成热流体波。沿径向运动的同时,伴随着热流体波的传播流体质点成对地绕顺时针和逆时针方向旋转。热流体波的周向传播速度较快,而流体质点的周向速度很小。分析发现,热流体波为对数螺线形波纹,其传播角为常数;随着Ma数的增大,传播角增大。更多还原

【Abstract】 In order to understand the natural characteristics of thermocapillary flow and hydrothermal wave,the thermocapillary convections are simulated numerically in a differentially heated shallow annular pool of silicone oil with depth of 1 mm.The results indicate that under small Marangoni(Ma) number,near the inner and outer wall,the two-dimensional steady axisymmetric flow increase its radial velocity component with increasing of Ma due to increase of temperature gradient.When Ma exceeds a critical value Mac,three-dimensional oscillatory convection occurs and hydrothermal wave comes out.Companying with traveling of hydrothermal wave,fluid elements flows along clockwise and anticlockwise directions as well as along radial direction.Though hydrothermal wave travels with large angular velocity,azimuthal velocity component of fluid elements is small.In shallow annular pool of silicone oil with moderate Pr number,the hydrothermal wave is a kind of logarithmic spiral curve with constant propagating angle.The propagating angle increases with increase of Ma.更多还原