The permeability and tortuosity of pore-scale two and three-dimensional random porous media were calculated using the Lattice Boltzmann method (LBM). Effects of geometrical parameters of medium on permeability and tortuosity were investigated as well. Two major models of random porous media were reconstructed by computerized tomography method: Randomly distributed rectangular obstacles in a uni...

The balancing Neumann-Neumann (BNN) and the additive coarse grid correction (BPS) preconditioner are fast and successful preconditioners within domain decomposition methods for solving partial differential equations. For certain elliptic problems these preconditioners lead to condition numbers which are independent of the mesh sizes and are independent of jumps in the coefficients (BNN). Here w...

Electroosmosis in homogeneously charged micro- and nanoscale random porous media has been numerically investigated using mesoscopic simulation methods which involve a random generation-growth method for reproducing three-dimensional random microstructures of porous media and a high-efficiency lattice Poisson-Boltzmann algorithm for solving the strongly nonlinear governing equations of electroos...

In this study an experimental work was performed to examine the effect of porous media on the heat transfer from a cylindrical heater in the case of steady-state forced convection. Porous media consisted of Spherical glasses of diameter 0.6 cm and air was used as the cooling fluid. The bulk temperature was approximated by the inlet temperature and Properties of the air were found at the film te...

Dispersion quantifies the impact of subscale velocity fluctuations on the effective movement of particles and the evolution of scalar distributions in heterogeneous flows. Which fluctuation scales are represented by and what is the meaning of dispersion, depends on the definition of the subscale, or the corresponding coarse graining scale. We study here the dispersion effect due to velocity flu...

Considering the numerous applications of the study of the flow due to leakage in a buried pipe in unsaturated porous media, finding a proper model to explain the influence of the effective factors is of great importance.There are various important factors involved in this type of flow such as: pipe leakage size and location, burial depth, the degree of the saturation of the surrounding porous m...

We present a variational multiscale mixed finite element method for the solution of Darcy flow in porous media, in which both the permeability field and the source term display a multiscale character. The formulation is based on a multiscale split of the solution into coarse and subgrid scales. This decomposition is invoked in a variational setting that leads to a rigorous definition of a (glob...

resin transfer molding (rtm) is a composite manufacturing process. a preformed fiber is placed in a closed mold and a viscous resin is injected into the mold. in this paper, a model is developed to predict the flow pattern, extent of reaction and temperature change during filling and curing in a thin rectangular mold. a numerical simulation is presented to predict the free surface and its inter...

a pressure-based coupled heat and mass transfer model was used to simulate temperature and soil suction in a drying process within a clay soil column. closed form functions were used for all parameters needed in the governing equations. model predictions were compared with experimental data using the mean relative percentage deviation method. thermocouples and mini-gypsum blocks were used t...

An increase in the flow velocity in flowthrough large porous media and deflection of flow regime from Darcy law causes a nonlinear relationship between hydraulic gradient and pore velocity of media. So many investigations have done previously in such Medias. One of the most important subjects in flowthrough large porous media is relationship between friction coefficient and flow characteristics...