81 2018年6月
流动与传递
过程工程学报
The Chinese Jourmal of Process Engineering
Vol.18 No.3 June2018
DOI: 10.12034/j.issn.1009-606X.217320
孔隙分布对多孔介质内流动和传热的影响余廷芳，柳阿亮，张莹，王志强，叶文林，孙金丛
(南昌大学机电工程学院，江西南昌330031)
摘要：采用Sierpinski地毯分形技术建立多孔介质内流动和传热模型，通过改变固体基质位置研究了孔隙分布结构对多孔介质内流动特性和热效率的影响，3种孔隙分布为每分形一次固体基质分布在中心位置(A)、分布在中上方(B)和分布在右上方(C)，当流体稳定流过多孔介质时，不同的孔隙分布表现出不同流动和传热特性，结果表明，孔隙分布是影响多孔介质传输特性和传热效率的重要因素，无量纲渗透率kc>k"s>k"A，多孔介质孔隙率大于0.8时更明显；流体流过不同孔隙分布的多孔介质时，相同孔
用Be表示的热传导引起的摘产率占主导
关键词：孔隙分布；Sierpinski地毯：多孔介质；渗透率；传热效率
中图分类号：TP301.6
文献标识码：A
文章编号：1009-606X(2018)030469-08
EffectofPoreDistributiononFlowandHeatTransferinPorousMedia TingfangYU,Aliang LIU,Ying ZHANG',Zhiqiang WANG,WenlinYE,Jincong SUN
(School of Mechanical and Electrical Engineering, Nanchang University, Nanchang, Jiangxi 330031, China)
saoesosoeadoaoeanseaersae effect of pore distribution on the transmission characteristics and heat transfer efficiency of porous media. The three pore distributions were distributed in a fractal primary solid matrix at the center (A), in the upper middle (B), and in the upper right (C). When the fluid flowed stably through the porous media model, the different pore distribution showed different flow and heat characteristics. The results showed that the pore distribution was an important factor affecting the transmission characteristics and heat transfer efficiency of porous media. The dimensionless permeability was expressed as k'c>k's>k'^. Especially when the porosity of porous media was more than 0.8, the effect of pore distribution on porous media permeability was more obvious. When the fluid flows through porous media with different pore distributions, the area of the fluidsolid contacting surface at the same porosity is A>B>C, and the heat transfer effect shows that A is the best and the C is the worst. At the same time, the pore distribution affects the change of the dimension of the non-dimensional local entropy. The pore distribution influences the dimensionless local entropy generation, and the entropy generation
onodosadoaeaeardoeoreaea Key words: pore distribution; Sierpinski carpet; porous media; permeability; heat transfer efficiency
1前言
多孔介质广泛存在于自然界中，被用于工业生产和工程。吸附、过滤、渗流、换热器、太阳能利用及催化反应等行业均离不开多孔介质[1-3，多孔介质内部孔隙的不均匀分布使其内部流动非常复杂，流型和流动阻力不断变化，传热效率差异很大，对多孔介质内部的流体固体耦合传热效果影响很大.黄永平等采用分形布朗运动模型定量描述了多孔介质，得到雷诺数Re和孔隙
率对渗透率的变化曲线.邓彩华等[5]建立了二维DNS模型，通过圆柱粒子叉排和顺排方式研究了多孔介质内流动的阻力和压降.Mehmani等[6]融合孔隙和微孔建立孔喉网络模型，模拟了多孔介质的流动特性.Sierpinski地毯分形技术常用于分析多孔介质性质，Chen等[7]采用 Sierpinski地毯分形方法，通过改变内部孔隙结构研究孔隙对多孔介质内流动渗透率的影响.Pian等[8]分析了多孔介质内孔隙结构对多孔介质有效热导率的影响，表明孔壁和大量小孔隙会降低多孔介质的有效热导率，
收稿日期：2017-0901，修园日期：2017-11-03
基金项目：国家自然科学基金资助项目(编号：51566012)：南昌大学研究生专项资金资助项目(编号：CX2016079)
作者简介：余廷芳(1974-），男，江西省南昌市人，博士，教授，研究方向为热力系统模拟优化；张堂，通讯联系人，E-mail:yzhan2033@163.com 引用格式：余廷芳，柳阿亮，张莹，等，孔障分布对多孔介质内流动和传热的影响，过程工程学报，2018,18(3)：469-476.
Yu T F, Liu A L, Zhang Y, et al. Effect of Pore Distribution on Flow and Heat Transfer in Porous Media (in Chinese). Chin. J. Process Eng. 2018, 18(3): 469476, DOI:10.12034/j.issn.1009-606X.217320.
万方数据