A Novel Permeability Model in Damaged Tree-Like Bifurcating Networks Considering the Influence of Roughness

Abstract

The seepage in tree-like bifurcating networks is a very common phenomenon in nature. The research on the transport characteristics of tree-like bifurcating networks has always been a hot topic. In this paper, a novel permeability model for fluid flow in damaged tree-like bifurcating networks is proposed. In the proposed model, the influence of roughness on permeability is considered by means of the fractal method. It is found that the permeability is not only related to the structural parameters of the network but also related to the damaged position and the number of damaged tubes at the damaged position. The effects of these parameters and damaged structure on permeability are discussed separately. The results show that the permeability reduces along with an increase in the roughness level, the length ratio, the number of damaged tubes, and the number of total bifurcating levels. Another major finding is that the permeability increases with an increase in the diameter ratio. Besides, we found that the damaged position and the number of damaged tubes at the damaged position have an important effect on the permeability. Increasing the number of damaged tubes and bringing the damaged position close to the front end of the network will reduce the permeability. Compared with the undamaged network, the permeability of damaged network has a significant decline. The proposed model may provide potential applications for the analysis of fluid flow in damaged tree-like bifurcating network.

New Model for Coal Gas Diffusion Based on the Fractal Tree-Like Bifurcation Network Structure

“…Nowadays, tree-like bifurcation network structures have been widely used in the field of characterization of porous media. Zhang and Xiao et al studied the heat conduction of asymmetric and damaged tree-like bifurcation networks embedded in porous media. , Liu et al, based on the tree-like bifurcation network structure, found that the permeability of the porous media was related to the damaged position and the number of damaged tubes at the damaged position and established a new permeability model . Liu et al used a tree-like bifurcation network to characterize the internal fracture network morphology of the coal body and established a seepage model for the fracture network of the water-injected coal body .…”

“… 11 , 12 Liu et al, based on the tree-like bifurcation network structure, found that the permeability of the porous media was related to the damaged position and the number of damaged tubes at the damaged position and established a new permeability model. 13 Liu et al used a tree-like bifurcation network to characterize the internal fracture network morphology of the coal body and established a seepage model for the fracture network of the water-injected coal body. 14 Jin, Zhou, and He et al used gas adsorption experiments to determine the fractal characteristics of the pore structures of coal bodies and analyze the relationship among the fractal dimensions of pores.…”