格拉晓夫数Gr对侧向局部加热腔体内对流结构的影响  

Effect of Grashof Number Gr on Convection Structure of Rectangular Cavity Heated Locally from Side

作　　者：李开继 宁利中[1] 宁碧波[2] 田伟利[3] 

机构地区：[1]西安理工大学西北旱区生态水利工程国家重点实验室培育基地,陕西西安710048 [2]嘉兴学院建筑工程学院,浙江嘉兴314001 [3]上海大学美术学院,上海200444

出　　处：《力学季刊》2016年第1期131-138,共8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项目(00X901)

摘　　要：通过二维流体力学基本方程组数值模拟,研究了Pr=6.949时侧向局部加热腔体内不同格拉晓夫数Gr对对流结构的影响.发现随着格拉晓夫数Gr增加出现以下四种情况:准定常流→单局部周期滚动→双局部周期滚动→定常流.还分析了周期对流阶段的对流特性.随着格拉晓夫数Gr增大,对流卷随时间移动的周期减小.随Gr增大,在0≤≤Y 5.2和0.5≤≤Y 5.7范围内对流卷逐渐消失,在5.2≤≤Y5和5.7≤≤Y10范围内对流卷由单对流卷变为多对流卷.The effect of different Grashof number Gr on the convection structure of rectangular cell heated locally from side was investigated by means of numerical simulation of 2-D equations of hydrodynamics when Prandtl number Pr=6.949. It is found out that the convection includes 4 cases with Gr increasing： quasi-steady flow→single periodic rolling→double periodic rolling→steady flow. In addition, the characteristics in periodic convection stage were analyzed. With the increase of Grashof number Gr, the periodic of convection roll decreases over time. The convection roll gradually disappears at 0≤Y≤ 5.2 and 0.5≤Y≤ 5.7, and the convection roll varies from single roll to multi-rolls at 5.2≤Y≤ 5 and 5.7≤Y ≤10 with the increase of Gr.

关 键 词：侧向局部加热 周期性 单局部滚动 双局部滚动 时空结构 定常或准定常流 

分 类 号：O357[理学—流体力学]