An adsorbate fluid of hard spheres is brought into contact with a semi-infinite porous matrix modeled by immobilized configurations of freely overlapping spheres with a sharp kink one-body density distribution. Comparison of results from a recent density-functional approach to those of our computer simulations yields good agreement for the adsorbate density profile across the matrix surface. We...

A novel approach was developed to prepare porous carbon materials with an extremely high surface area of 2459.6 m(2)g(-1) by using Aspergillus flavus conidia as precursors. The porous carbon serves as a superior cathode material to anchor sulfur due to its uniform and tortuous morphology, enabling high capacity and good cycle lifetime in lithium sulfur-batteries. Under a current rate of 0.2 C, ...

A numerical method for a 2-dimensional surface fire model taking into account moisture content and radiation is developed. We consider the combustion of a porous solid, where a simplified energy conservation equation is applied. The effects of the moisture content and the endothermic pyrolysis of the vegetation are introduced in the model by means of a multivalued function representing the enth...

Two flow problems relevant to fuel cell modeling are simulated with the lattice-Boltzmann (LB) approach. The first is a 3D viscous flow through a section of serpentine channel and the second is a 2D channel filled or partially filled with porous medium. In the first case, attention is given to the implementation details such as inlet–outlet boundary conditions, nonuniform grid, and forcing. It ...

We study the formation of viscous fingering and fracturing patterns that occur when air at constant overpressure invades a circular Hele-Shaw cell containing a liquid-saturated deformable porous medium—i.e., during the flow of two non-miscible fluids in a confined granular medium at high enough rate to deform it. The resulting patterns are characterized in terms of growth rate, average finger t...

New porous biomaterials based on hydroxyapatite (HAp) were designed as obturation materials for dental cavities. Synthetic HAp powder with a particle diameter of 150 m was agglutinated using three different polyurethane monocomponents (rigid, semi-rigid, and flexible), enabling the matching of their properties to those of real teeth. Alumina particles were also added in some cases. Our new hybr...

Modified Moving Particle Semi-implicit (MMPS) is a particle-based method used to simulate pore-scale fluid flow through disordered porous media. We present a multi-GPU implementation of MMPS for hybrid CPU–GPU clusters using NVIDIA’s Compute Unified Device Architecture (CUDA). Message Passing Interface (MPI) functions are used to communicate between different nodes of the cluster and hence thei...

This paper provides a comprehensive study on the heat transfer and entropy generation rates in a channel partially filled with a porous medium and under constant wall heat flux. The porous inserts are attached to the walls of the channel and the system features internal heat sources due to exothermic or endothermic physical or physicochemical processes. Darcy-Brinkman model is used for modellin...

A tissue-engineering scaffold resembling the structure of the natural extracellular matrix can often facilitate tissue regeneration. Nerve and tendon are oriented micro-scale tissue bundles. In this study, a method combining injection molding and thermally induced phase separation techniques is developed to create single- and multiple-channeled nanofibrous poly(L-lactic acid) scaffolds. The ove...

In this paper, we propose two novel semi-blind channel estimation techniques based on QR decomposition for Rayleigh flat fading Multiple Input Multiple output (MIMO) channel using various pilot symbols. In the first technique, the flat-fading MIMO channel matrix H can be decomposed as an upper triangular matrix R and a unitary rotation matrix Q as H = RQ. The matrix R is estimated blindly from ...