Liquid distributions in unsaturated porous media under different gravitational accelerations and corresponding macroscopic gaseous diffusion coefficients were investigated to enhance understanding of plant growth conditions in microgravity. We used a single-component, multiphase lattice Boltzmann code to simulate liquid configurations in two-dimensional porous media at varying water contents fo...

1 Fellow, ASME Abstract A semi-empirical model for conduction/convection in a thin “fin-like” porous wall of arbitrary composition and thickness is developed. The model assumes one-dimensional conduction in the porous matrix and one-dimensional flow of the coolant through the wall. Closed form solutions are obtained for a uniform composition and thickness porous wall having an insulated tip. An...

The enactment of strict laws on reducing pollution and controlling combustion has given rise to the necessity of considering a new approach to energy supply in the future. One such approach is the use of hydrogen as an alternative to fossil fuels. Hydrogen and synthesis gas are typically produced through the partial oxidation of methane in porous media. This process was theoretically simula...

Abstract Solute transport under single-phase flow conditions in porous micromodels was studied using high-resolution optical imaging. Experiments examined loading (injection of ink-water solution into a clear water-filled micromodel) and unloading water an filled micromodel). Statistically homogeneous fine-coarse patterns were used. It is shown that the time scale during larger than loading, ev...

The irreversibility of heat conduction in porous media, its relation to effective thermal conductivities (ETCs), and the optimization of thermal conduction process are investigated in this work based on the concept of entransy dissipation. Two more new concepts of reference entransy dissipation and nondimensional entransy dissipation are first introduced. Then it is showed that the nondimension...

This work investigated the effect of different surface modification methods, including oxidization, surfactant coating, and humic acid coating, on single-walled carbon nanotube (SWNT) stability and their mobility in granular porous media under various conditions. Characterization and stability studies demonstrated that the three surface modification methods were all effective in solubilizing an...

We use Lattice Boltzmann models to simulate solute transport in porous media traversed by larger conduits and fit the resulting solute breakthrough curves with macroscopic Continuous Time Random Walk (CTRW) models. In this paper, the porous media are simulated using a real-numbered coefficient that partially damps the inertial components of the flow and, when the damping is large enough, leads ...

We present a pore-scale study of two-phase relative permeability in homogenous-wet porous media, and porous media altered to a mixed-wet state. A Shan-Chen type multicomponent lattice Boltzmann (LB) model is employed to determine pore-scale fluid distributions and relative permeability. Mixedwet states are created by altering the wettability of solid surfaces in contact with the nonwetting phas...

The fundamental solution or Green's function for flow in porous media is determined using Stokesian dynamics, a molecular-dynamics-like simulation method capable of describing the motions and forces of hydrodynamically interacting particles in Stokes flow. By evaluating the velocity disturbance caused by a source particle on field particles located throughout a monodisperse porous medium at a g...

The BDDC (balancing domain decomposition by constraints) algorithms are similar to the balancing Neumann-Neumann methods, with a small number of continuity constraints enforced across the interface throughout the iterations. These constraints form a coarse, global component of the preconditioner. The BDDC methods are powerful for solving large sparse linear algebraic systems arising from discre...