A Fractal Model for Thermal Dispersion Coefficients of Porous Media

ZHANG Jie; ZHANG Sai; GAO Weiye; HU Shiwang; WANG Zhenyi

doi:10.21656/1000-0887.420314

Volume 43 Issue 5

May 2022

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Article Navigation > Applied Mathematics and Mechanics > 2022 > 43(5): 553-560

ZHANG Jie, ZHANG Sai, GAO Weiye, HU Shiwang, WANG Zhenyi. A Fractal Model for Thermal Dispersion Coefficients of Porous Media[J]. Applied Mathematics and Mechanics, 2022, 43(5): 553-560. doi: 10.21656/1000-0887.420314

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A Fractal Model for Thermal Dispersion Coefficients of Porous Media

doi: 10.21656/1000-0887.420314

Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650500, P.R.China

Received Date: 2021-10-18
Rev Recd Date: 2021-12-08

Available Online: 2022-04-07

Publish Date: 2022-05-01

Abstract

Abstract

The thermal dispersion coefficient is an important parameter to characterize heat and mass transfer in porous media, which is related to the physical properties of fluid and the structure of porous media. The pore-throat structure model for fractal porous media was established, and the local head loss and the velocity dispersion effect were studied for the fluid changing from the turbulent state to the laminar state around the pore-throat structure. The thermal dispersion coefficient formula was derived under the influences of the micropore-throat structure and the velocity dispersion effect. The results show that, the thermal dispersion coefficient is directly proportional to the pore-throat ratio, the number of pore-throat structures and the tortuous fractal dimension, and is inversely proportional to the porosity and the area fractal dimension. Furthermore, in the range of 1~150, the pore-throat ratio has a significant influence on the velocity dispersion effect, and the fluid has a local head loss around the pore-throat structure, which leads to an enhancement of the velocity dispersion effect and an increase of the thermal dispersion coefficient.
- porous media,
- pore-throat ratio,
- local head loss,
- fractal,
- heat dispersion

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References(15)

References

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