收稿日期: 2004-06-09
修回日期: 2004-07-09
网络出版日期: 2005-03-15
基金资助
国家自然科学基金项目(50336040)资助
Double Diffusive Convection in an Annular Vertical Cavity
Received date: 2004-06-09
Revised date: 2004-07-09
Online published: 2005-03-15
通过数值模拟,研究了温度和浓度梯度为水平方向、内壁和外壁上的温度和浓度保持定值的竖直环形容器内的双扩散对流结构,其中浮升力之比N=GrSGrT=-1,GrS和GrT分别为溶质格拉晓夫数和热格拉晓夫数.首先对环形容器与矩形容器内的双扩散对流状况进行了比较;然后着重分析了在双扩散对流情况下竖直环形容器内壁面处的热(溶质)边界层以及平均传热(质)率Nu(Sh)随Le数的变化情况.结果表明,溶质边界层的厚度随着Le数的增大逐渐减小,而热边界层随Le数的变化不大;与Sh数一直随Le数的增大呈明显的上升趋势不同,当Le>10后Nu数随Le数的变化趋于平缓.
石科峰 , 卢文强 . 环形容器内双扩散对流的数值模拟[J]. 中国科学院大学学报, 2005 , 22(2) : 152 -156 . DOI: 10.7523/j.issn.2095-6134.2005.2.005
A numerical study is presented of the structure of double diffusive convection in an annual cavity with horizontal heat and mass gradients due to constant temperatures and concentrations along the vertical side-walls,respectively.The buoyancy ratio N =GrS GrT is equal to-1, where GrS and GrT are the solutal and thermal Grashof numbers, respectively.The structures of double diffusive convection in rectangular and annular cavity were compared.Numerical results are reported for the effect of the Le numbers on the thermal (solute)boundary layer and the average rate of heat (mass)transfer Nu(Sh).The results show that the thickness of solutal boundary layer decreases when the Lewis Number increases, but the thermal boundary is not significantly influenced when the Lewis number varies ;contrasting with the steady increase of the Sherwood number, the Nusselt number varies slowly when the Lewis number is higher than 10.
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