作　　者： (李开继）; (宁利中）; (宁碧波）; (田伟利）; (刘扬）; (王锦辉）;

机构地区： 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,西安710048 兰州建设投资控股集团有限公司,兰州730000

出　　处： 《应用力学学报》 2017年第4期641-646,共6页

摘　　要： 通过采用SIMPLE算法求解二维流体力学基本方程组,研究了侧壁面正弦加热条件下普朗特数Pr=6.94的流体自然对流的动力学特性。结果表明,当格拉晓夫数Gr=4.4×10~3时系统由稳态阶段向周期阶段转变。在周期性阶段存在两种特殊的对流结构,它们是单局部对流卷和双局部对流卷;给出了特征物理量的分布及变化规律;说明垂直最大流速、水平最大流速、努塞尔数随着格拉晓夫数的增加而增加。最后,分析了腔体宽度对热壁面传热能力的影响,发现:当高宽比一定条件下,腔体宽度较大时,热壁面的传热能力较弱;对于宽度d分别为1cm和2cm的腔体,随着格拉晓夫数增大,最大努塞尔数的差值增大。 The two dimensional equations of hydrodynamics are solved by using the SIMPLE algorithm. Dynamics of natural convection sinusoidal heating from side with Prandtl number Pr=6. 94 is studied. Results show that the system changed from steady state to periodic phase at Grashof number Gr=4. 4×10~3. Two new types of convection structures are observed in periodic-stage, and they are single local convection roll and double local convection rolls. The distributions of physical characteristic parameters and the laws are given and it is found that the maximum vertical velocity, the maximum horizontal velocity and the Nusselt number increase with increasing of Grashof number. Finally, the influence of the width of cavity on the heat-transfer capability of hot wall is analyzed. It is found that the heat transfer ability of the hot wall surface is weaker for large width of cavity when an aspect ratio is constant, and the difference between the maximum Nusselt number for the width of cavity d=1 cm and d=2 cm increases with the Grashof number.

关 键 词： 侧壁面正弦加热 时空结构 周期阶段 特征物理量 传热能力