Two-phase flow in correlated pore-throat random porous media
Tian Ju-Ping (田巨平)a, Yao Kai-Lun (姚凯伦)b
a Department of Physics, Wuhan Institute of Science and Technology, Wuhan 430073, China; b Department of Physics Huazhong University of Science and Technology, Wuhan 430074, China; CCAST (World Laboratory), Beijing 100080, Chinab International Center for Material Physics, Chinese Academy Science, Shenyang 110015, China
Abstract We have constructed a porous media model in which there are percolation clusters with varying percolation probability P and correlated site-bonds. Taking into account both the pore and the throat geometry, the viscous fingering (VF) in porous media has been investigated by using the standard over-relaxed Gauss-Seidel scheme. The simulation results show that the VF structure varies with the correlation parameter , the viscosity ratio M and the percolation probability P. The smaller the correlation parameter , the greater the deviation of the normalized size distribution of the invaded throat Ninv(r) from the truncated Rayleigh distribution. For a larger viscosity ratio M, the VF pattern looks like a diffusion-limited-aggregation structure in percolation clusters. The fractal dimension D increases with the increase of the percolation probability P and the correlation parameter ε. The velocity distribution of VF in percolation clusters is of a parabola-like curve. The tail of the distribution (large ) is longer for a larger correlation parameter . For a smaller , the distribution is very sharp. The sweep efficiency E decreases along with the decrease of the correlation parameter and the increase of the network size Lnz. E has a minimum as Lnz increases up to the maximum no matter what the values of P, M and . The E～Lnz curve has a frozen zone and an active zone. The geometry and the topology of the porous media have strong effects on the displacement processes and the structure of VF.
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.
