二维流化床中流动的非线性特性分析  

Nonlinear Analysis of Flow in a Two-dimensional Fluidized Bed

作　　者：刘桂良 杨茉[1] LIU Gui-Liang;YANG Mo(University of Shanghai for Science and Technology,School of Energy and Power Engineering,Shanghai 200093,China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《工程热物理学报》2021年第10期2566-2574,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.51736007)。

摘　　要：本文建立简化二维流化床模型对其进行数值求解,对流场内九个点监测压力与固相体积分数数据。对数据进行后处理计算流场的关联维度与K熵,通过比较判别系统混沌程度与气速关系。结果显示随着气速增加,系统混沌程度增加。相空间重构图像、关联维数与K熵结果均显示出流场存在不对称,相比于相空间重构图,关联维度与K熵更精准地表示监测点时间序列的混沌强度。压力项与固相体积分数混沌程度变化并不对应。随流速增加气固交换混沌程度的较大值由中部转移至两侧并且左右数值更加趋近相同,压力关联维度在底部随速度先增后降。In this paper,a simplified two-dimensional fluidized bed model was established to solve the problem numerically.The data of pressure and solid volume fraction were monitored at nine points in the flow field.The correlation dimension and k-entropy of the flow field were calculated after the data were post-processed,and the relation between the degree of chaos and the gas velocity of the system was distinguished by comparison.The results show that the degree of chaos increases with the increase of gas velocity.Phase space reconstruction images,correlation dimension and k-entropy results all show that the flow field has asymmetry.Compared with phase space reconstruction,correlation dimension and k-entropy can more accurately represent the chaotic intensity of the time series of the monitoring points.The pressure term does not correspond to the change of the degree of chaos of the solid volume fraction.With the increase of velocity,the larger value of gas-solid exchange chaos degree shifted from the middle to the two sides and the left and right values became more similar.The pressure correlation dimension at the bottom first increased and then decreased with the increase of velocity.

关 键 词：流化床 非线性 混沌 Kolmogorov熵 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理]