中国物理B ›› 2020, Vol. 29 ›› Issue (5): 54701-054701.doi: 10.1088/1674-1056/ab7b53

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Numerical study on permeability characteristics of fractal porous media

Yongping Huang(黄永平), Feng Yao(姚峰), Bo Zhou(周博), Chengbin Zhang(张程宾)   

  1. 1 Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China;
    2 Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
  • 收稿日期:2019-12-19 修回日期:2020-01-19 出版日期:2020-05-05 发布日期:2020-05-05
  • 通讯作者: Chengbin Zhang E-mail:cbzhang@seu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 51776037 and 51806147) and Natural Science Foundation of Jiangsu Province, China (Grant No. BK20170082).

Numerical study on permeability characteristics of fractal porous media

Yongping Huang(黄永平)1, Feng Yao(姚峰)2, Bo Zhou(周博)2, Chengbin Zhang(张程宾)1   

  1. 1 Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China;
    2 Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
  • Received:2019-12-19 Revised:2020-01-19 Online:2020-05-05 Published:2020-05-05
  • Contact: Chengbin Zhang E-mail:cbzhang@seu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 51776037 and 51806147) and Natural Science Foundation of Jiangsu Province, China (Grant No. BK20170082).

摘要: The fractal Brownian motion is utilized to describe pore structures in porous media. A numerical model of laminar flow in porous media is developed, and the flow characteristics are comprehensively analyzed and compared with those of homogeneous porous media. Moreover, the roles of the fractal dimension and porosity in permeability are quantitatively described. The results indicate that the pore structures of porous media significantly affect their seepage behaviors. The distributions of pressure and velocity in fractal porous media are both non-uniform; the streamline is no longer straight but tortuous. When Reynolds number Re < 1, the dimensionless permeability is independent of Reynolds number, but its further increase will lead to a smaller permeability. Moreover, due to the higher connectivity and enlarged equivalent aperture of internal channel network, the augment in porosity leads to the permeability enhancement, while it is small and insensitive to porosity variation when ε < 0.6. Fractal dimension also plays a significant role in the permeability of porous media. The increase in fractal dimension leads to the enhancement in pore connectivity and a decrease in channel tortuosity, which reduces the flow resistance and improves the transport capacity of porous media.

关键词: seepage, fractal Brownian motion, porous media, fractal dimension

Abstract: The fractal Brownian motion is utilized to describe pore structures in porous media. A numerical model of laminar flow in porous media is developed, and the flow characteristics are comprehensively analyzed and compared with those of homogeneous porous media. Moreover, the roles of the fractal dimension and porosity in permeability are quantitatively described. The results indicate that the pore structures of porous media significantly affect their seepage behaviors. The distributions of pressure and velocity in fractal porous media are both non-uniform; the streamline is no longer straight but tortuous. When Reynolds number Re < 1, the dimensionless permeability is independent of Reynolds number, but its further increase will lead to a smaller permeability. Moreover, due to the higher connectivity and enlarged equivalent aperture of internal channel network, the augment in porosity leads to the permeability enhancement, while it is small and insensitive to porosity variation when ε < 0.6. Fractal dimension also plays a significant role in the permeability of porous media. The increase in fractal dimension leads to the enhancement in pore connectivity and a decrease in channel tortuosity, which reduces the flow resistance and improves the transport capacity of porous media.

Key words: seepage, fractal Brownian motion, porous media, fractal dimension

中图分类号:  (Laminar flows)

  • 47.15.-x
47.56.+r (Flows through porous media) 47.53.+n (Fractals in fluid dynamics)