We study through numerical simulations the dependence of the hydraulic permeability of granular materials on the particle shape and the grain size distribution. Several models of sand are constructed by simulating the settling under gravity of the grains; the friction coefficient is varied to construct packs of different porosity. The size distribution and shapes of the grains mimic real sands....

The aim of the research that is presented in this paper was to evaluate the physical and mechanical properties of heat-insulating mortars with expanded cork aggregates and different binders. In this work, the measurements of surface roughness and adhesion strength, supported by determination of basic mechanical and physical parameters, such as density, bulk density, open porosity, total porosit...

A study has been conducted on the acoustic response of perforated plates at normal incidence. The investigation includes a theoretical analysis of the problem, with validation through experimentation. The acoustic response was quantified through the transmission loss and absorption coefficient of the perforate. The theoretical analysis is based on planar wave propagation through a single contra...

Friction plays an important role in the behavior of flowing granular media. The effective friction coefficient is a description of shear strength in both slow and rapid flows of these materials. In this paper, we study the steady state effective friction coefficient μ in a granular material in two steps. First, we develop a new relationship between the steady state effective friction coefficien...

The effect of variety and moisture content on some engineering properties of five improved paddy rice varieties was investigated within moisture content range of 10% and 30% dry basis (d.b.). Increase in moisture content was found to increase the linear dimensions, mass of 100 seeds, surface area, apparent volume, true volume, arithmetic mean diameter, effective geometric diameter, sphericity, ...

original article   electrospun nanofibrous filter media have attracted considerable attention in the last decade. the present study aimed to develop the electrospun pan (polyacrylonitrile) filter media through experimental investigations for application in high-performance air filters. for this purpose, an experimental design was proposed to assess the effect of electrospinning process conditio...

porosity is considered as an important petrophysical parameter in characterizing reservoirs, calculating in-situ oil reserves, and production evaluation. nowadays, using intelligent techniques has become a popular method for porosity estimation. support vector machine (svm) a new intelligent method with a great generalization potential of modeling non-linear relationships has been introduced fo...

The paper has studied the influences of the volume content and slenderness ratio of fibrillated polypropylene fiber on the impermeability durability of self-consolidating concrete (SCC) reinforced with the fibrillated polypropylene fiber, and proposed to use the modified relative permeability coefficient method to evaluate the water-resistant properties of SCC reinforced with the fiber. Also, t...

The double porosity model allows to compute the pressure at a macroscopic scale in a fractured porous media, but requires the computation of some exchange coeecient characterizing the passage of the uid from and to the porous media (the matrix) and the fractures. We propose a new Monte Carlo method to estimate this coeecient. Here we give an overview of Campillo et al 1, 2].