Domain decomposition and multigrid solvers for flow simulation in porous media on distributed memory parallel processors

1992 ◽  
Vol 7 (2) ◽  
pp. 127-162
Author(s):  
R. Bhogeswara ◽  
J. E. Killough
2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Zhenglun Alan Wei ◽  
Zhongquan Charlie Zheng ◽  
Xiaofan Yang

A parallel implementation of an immersed-boundary (IB) method is presented for low Reynolds number flow simulations in a representative elementary volume (REV) of porous media that are composed of a periodic array of regularly arranged structures. The material of the structure in the REV can be solid (impermeable) or microporous (permeable). Flows both outside and inside the microporous media are computed simultaneously by using an IB method to solve a combination of the Navier–Stokes equation (outside the microporous medium) and the Zwikker–Kosten equation (inside the microporous medium). The numerical simulation is firstly validated using flow through the REVs of impermeable structures, including square rods, circular rods, cubes, and spheres. The resultant pressure gradient over the REVs is compared with analytical solutions of the Ergun equation or Darcy–Forchheimer law. The good agreements demonstrate the validity of the numerical method to simulate the macroscopic flow behavior in porous media. In addition, with the assistance of a scientific parallel computational library, PETSc, good parallel performances are achieved. Finally, the IB method is extended to simulate species transport by coupling with the REV flow simulation. The species sorption behaviors in an REV with impermeable/solid and permeable/microporous materials are then studied.


2019 ◽  
Vol 142 (4) ◽  
Author(s):  
Hamed Movahedi ◽  
Mehrdad Vasheghani Farahani ◽  
Mohsen Masihi

Abstract In this paper, we present a computational fluid dynamics (CFD) model to perform single- and two-phase fluid flow simulation on two- and three-dimensional perforated porous media with different perforation geometries. The finite volume method (FVM) has been employed to solve the equations governing the fluid flow through the porous media and obtain the pressure and velocity profiles. The volume of fluid (VOF) method has also been utilized for accurate determination of the volume occupied by each phase. The validity of the model has been achieved via comparing the simulation results with the available experimental data in the literature. The model was used to analyze the effect of perforation geometrical parameters (length and diameter), degree of heterogeneity, and also crushed zone properties (permeability and thickness) on the pressure and velocity profiles. The two-phase fluid flow around the perforation tunnel under the transient flow regime was also investigated by considering a constant mass flow boundary condition at the inlet. The developed model successfully predicted the pressure drop and resultant temperature changes for the system of air–water along clean and gravel-filled perforations under the steady-state conditions. The presented model in this study can be used as an efficient tool to design the most appropriate perforation strategy with respect to the well characteristics and reservoir properties.


2017 ◽  
Vol 5 (1) ◽  
pp. SB57-SB67 ◽  
Author(s):  
Nattavadee Srisutthiyakorn ◽  
Gerald M. Mavko

Hydraulic tortuosity is an important parameter in characterizing fluid-flow heterogeneity in porous media. The most basic definition of tortuosity is the ratio of the average flow path length to the sample length. Although this definition seems straightforward, the lack of understanding and the lack of proper ways to measure tortuosity make it one of the most abused parameters in rock physics. Hydraulic tortuosity is often treated merely as a fitting factor, or worse, it is neglected by being combined with a geometric factor in the Kozeny-Carman (KC) equation. Often, the tortuosity is obtained from laboratory measurements of porosity, permeability, and specific surface area by inverting the KC equation. This approach has a major pitfall because it treats tortuosity as a fitting factor, and the inverted tortuosity is often unphysically high. In contrast, we obtained the tortuosity from 3D segmented binary images of porous media using streamlines extracted from a local flux, the output from the lattice Boltzmann method (LBM) flow simulation. After obtaining streamlines from each sample, we calculated the distribution of tortuosities and flux-weighted average tortuosity. With the tortuosity measurement from streamlines, every parameter in the KC equation can be measured accurately from 3D segmented binary images. We found, however, that the KC equation is still missing some important geometric information needed to predict permeability. With known parameters and without a fitting factor, the KC equation predicts permeability higher by one to two orders of magnitude than that predicted by the LBM. We searched for a missing parameter by exploring various concepts such as connected pore space and pore throat distribution. We found that the connected pore space does not contribute to the difference between the KC permeability and LBM permeability, whereas, as we learn with sinusoidal pipe examples, the pore throat distribution captures what is missing from the KC equation.


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