中文摘要：

为了了解普朗特数对具有表面蒸发的环形液池内热毛细对流的影响，对流体在其纯蒸汽环境中蒸发时的热毛细对流进行了数值模拟，流体Pr变化范围为O．01至50．00，环形液池半径比和深宽比分别为O．5和1．0。结果表明，随着Pr的增加，表面温度逐渐升高，表面蒸发质量通量增大，热毛细对流流胞逐渐向外壁和自由表面移动，这种影响随着蒸发Biot数增加而逐渐减小；当蒸发Bi较小时，总蒸发质量随Pr增加而增大，当Bi较大时，Pr对总蒸发质量影响很小。

英文摘要：

The numerical simulations on thermocapillary convection of the fluids with Prandtl number from 0.01 to 50.00 in the pure stream evaporation were carried out to understand the effect of Prandtl number on thermocapillary convection with surface evaporation in an annular pool. The radius ratio and the aspect ratio of the annular liquid pool are 0.5 and 1.0, respectively. The results show that with the increase of Prandtl number, the surface temperature rises gradually, the evaporative mass flux increases, and the thermocapillary convection cell moves gradually toward the outer wall and the free surface. These effects decrease with the increase of evaporation Biot number. When evaporation Blot number is smaller, the total evaporation mass increases with the increase of Prandtl number~ when Biot number is larger, the effect of Prandtl number on the total evaporation mass is very small.