微重力条件下悬浮区中的Marangoni对流

本文研究微重力条件下悬浮区中的表面张力梯度驱动对流。采用有限元方法数值研究二维、轴对称悬浮区中的定常流动和温度分布,讨论P_r数及自由面上散热条件的影响。计算表明,P_r数(M_α数)增大时,流区大部分自由表面上温度梯度减小,流区流速较小,对流热输运较扩散效应增强。只要能维持自由面上一定的温度梯度,在较大的P_r数(M_α数)时,仍能得到收敛的定常解。

THERMAL MARANGONI CONVECTION IN FLOATING ZONES UNDER MICROGRAVITY CONDITIONS

The convection driven by surface tension in floating zones under raicrogravity condition is studied in present paper.The Finite Element Method is used to determine the two-dimensional,axisymm(?)tric steady flow and temperature fields.The interest of this study is centered on the effects of the prandtl number and surface heat loss.The results show that the tangential temperature gradient in the considerable section of free surface and the flow velocity in the liquid bridge decrease as Prandtl number increases, and compared with thermal diffusion the thermal convection becomes more and more dominant over most of the floating-zon(?).A convergent steady flow pat tern and temperature field for a higher Pr (Ma) number can be get if a certain temperature gradient along free surface is maintained.