孔喉结构薄膜热质传递的分形模型  

Fractal Model of Heat and Mass Transfer in Pore-throat Structure Membrane

作　　者：张杰[1] 张赛[1] 高伟业 胡世旺 汪振毅 Zhang Jie;Zhang Sai;Gao Weiye;Hu Shiwang;Wang Zhenyi(School of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming City,Yunnan Province 650500,China)

机构地区：[1]昆明理工大学机电工程学院,云南省昆明市650500

出　　处：《农业装备与车辆工程》2022年第11期26-31,共6页Agricultural Equipment & Vehicle Engineering

基　　金：昆明理工大学省级项目(人培)“多孔材料热质传递及耦合问题的分形研究”(KKSY201601011);云南省科学技术厅青年基金项目“基于分形理论的多孔材料热质传递系数与热-质全耦合数学模型”(KKSQ201701008)。

摘　　要：运用分形理论,建立了气体在膜介质中的流速模型,基于流速模型推导出气体通过膜介质的扩散系数模型和换热系数模型。分析了膜介质的孔喉比、迂曲分形维数、面积分形维数、孔隙率和固体颗粒直径等微观结构参数对膜介质传热传质的影响。结果表明,孔喉微观结构参数对膜介质的传热传质过程具有重要影响。扩散系数和换热系数与孔隙率、固体颗粒直径和面积分形维数呈正比。喉道直径一定时,固体颗粒直径增大,膜介质内部孔隙直径增加,流动阻力变小,膜介质的传热传质能力增强;扩散系数和换热系数与孔喉比、迂曲分形维数呈反比;固体颗粒直径一定时,孔喉比增大,喉道直径变小,迂曲分形维数增大,面积分形维数减小,流动阻力变大,膜介质的传热传质能力减弱。The fractal theory is used to establish the flow velocity model of gas in the membrane media,and based on the flow velocity model,the diffusion coefficient model and heat transfer coefficient model of gas through the membrane medium are deduced.Analyzed the effects of pore-throat ratio,tortuous fractal dimension,surface integral dimension,porosity and solid particle diameter on heat and mass transfer in membrane media.The results showed that the pore and throat microstructure parameters have an important effect on heat and mass transfer in membrane media.The porosity,solid particle diameter and surface integral dimension are positively proportional to the diffusion coefficient and heat transfer coefficient.When the throat diameter is constant,the solid particle diameter increases,the pore diameter inside the membrane medium increases,the flow resistance decreases,and the heat and mass transfer ability of the membrane medium increases.The pore-throat ratio and tortuous fractal dimension are inversely proportional to the diffusion coefficient and heat transfer coefficient.When the diameter of solid particles is constant,the pore-throat ratio increases,the throat diameter decreases,the tortuous fractal dimension increases,the surface integral dimension decreases,the flow resistance increases,and the heat and mass transfer ability of membrane medium decreases.

关 键 词：膜介质 孔喉结构 传热传质 分形理论 

分 类 号：TK121[动力工程及工程热物理—工程热物理]