摘要
通过二维流体力学方程组的数值模拟,探讨了普朗特数Pr(28)703.0时高宽比A(28)10矩形腔体内侧向局部加热自然对流在初始小扰动下的成长情况和格拉晓夫数(Gr)对对流的影响规律.研究表明,流速场线性成长阶段扰动的成长率mγ是格拉晓夫数的函数,并给出了成长率随着格拉晓夫数的变化关系式.随着Gr数的增加,对流斑图按定常流—周期—准周期变化,在周期性阶段观察到了2种新的对流斑图,即相位错位对流斑图和同相位对流斑图.最后,探讨了腔体尺寸(d)对对流振幅和热壁面传热能力的影响.
Using the numerical simulations of 2-D equations of hydrodynamics,the growth of perturbation and the effects of Grashof number（ Gr） on convection in a cavity of heating locally from side wall with a Prandtl number Pr（28）703.0 and in a rectangular cell with a high-aspect-ratio A=10 are studied. It is found that the growth ratemγ of perturbation in linear stage of velocity field is a function of Gr number, and a formula for varition of the growth rate with Gr number is proposed. The convection pattern develops in the form of steady-periodic-quasi periodic with the increase of Gr number. Two new types of convection patterns are observed in periodic-stage, which are phase-dislocation and same phase. At last, the influence of the size of cell（d） on the convection amplitude and the heat transfer capability of hot wall is discussed.
出处
《力学季刊》
CSCD
北大核心
2017年第4期703-709,共7页
Chinese Quarterly of Mechanics
基金
国家自然科学基金(10872164)
陕西省重点学科建设专项资金(00X901)
西北旱区生态水利工程国家重点实验室培育基地基金(2017ZZKT-2)
关键词
初始小扰动
分叉曲线
对流斑图
振幅
传热能力
initial small perturbation
bifurcated curve
convection pattern
amplitude
heat transfer capability
