结构化填充床内非平衡性的数值研究

Numerical study of non-equilibrium in structured packed bed

中文关键词: 数值研究  非平衡性  多孔介质

英文关键词: numerical simulation  non-equilibrium  porous media

中文摘要:

      利用孔隙尺度介观方法对有序排列多孔介质小球的二维填充床进行数值研究。在考虑小球内部的热传导和小球表面的辐射换热基础上,研究空气流入填充床内部时,固体和气体之间热的非平衡性以及局部和整体之间的流动特性。数值计算与实验结果吻合较好。结果表明：在填充床内部,相邻小球之间和整个区域的不同位置均存在热的非平衡现象。当空气流速从0.23-0.63m/s时,最高温度逐渐降低,但是高温区域的范围逐渐扩大。同时,无量纲速度在填充床内呈阶梯式抛物线变化,其值在0-8.3之间,速度非平衡特性较明显。

英文摘要:

      Numerical simulations of pore-level was used to numerically appreciate the thermal non-equilibrium between solids and gases and the flow characteristics between local and global of orderly arrangement porous medium sphere arranged in a 2D packed bed, which is under the conditions of the high-temperature and considers the heat transfer inside the particles and the radiation heat transfer on the surface of the particles. The simulation values qualitatively agree with the experimental data. The results show that thermal non-equilibrium exists in different positions of adjacent spheres and the whole zone in the packed bed. When the inlet velocity is from 0.23 m / s to 0.63 m / s, the maximum temperature decreases gradually, but the range of high temperature region increases gradually. Additional, the normalized velocity in the packed bed changes in a step-type parabola, its value is between 0-8.3, and the velocity non-equilibrium characteristic is obvious.