A simulation methodology for predicting the fatigue life of cast steel components with shrinkage porosity is developed and validated through comparison with previously performed measurements. A X-ray tomography technique is used to reconstruct the porosity distribution in 25 test specimens with average porosities ranging from 8 to 21 pct. The porosity field is imported into finite element analy...

BACKGROUND In geochemically perturbed systems where porewater and mineral assemblages are unequilibrated the processes of mineral precipitation and dissolution may change important transport properties such as porosity and pore diffusion coefficients. These reactions might alter the sealing capabilities of the rock by complete pore-scale precipitation (cementation) of the system or by opening n...

The porosity of uniaxially compacted cohesive powders depends on the applied stress (including gravity). The case, where these stresses are weak, is considered. The compaction results in a porosity which is a function of sliding, rolling and torsion friction. By contact dynamics simulations it is shown that the influences of contact torques (static rolling and torsion friction) on the porosity ...

in the present study, the effect of porosity on the cathode microstructure (50:50 wt. % lsm: ysz) of a solid oxide fuel cell (sofc) has been examined. a 3-d finite element method for mixed ionic and electronic conducting cathodes (miec) is presented to study the effects of porosity on cell performance. each microstructure was realized using the monte carlo approach with the isotropic type of gr...

for obtaining reservoir petrophysical properties, for example porosity, non-destructive methods such as x-ray computed tomography, ct, seems to be precise and accurate. porosity is deducted from the ct image with a single scan via different techniques, such as pore space detection by image segmentation techniques then correlation with porosity. more than one hundred samples with carbonate litho...

This paper presents the experimental results of the investigation of various properties related to the durability and longterm performance of mortars made of Fly Ash blended cement, FA and Ordinary Portland cement, OPC. The properties that were investigated in an experimental program include; equilibration of specimen in different relative humidity, determination of total porosity, compressive ...

We investigated the fabrication of highly porous scaffolds made of three different materials [poly(propylene fumarate) (PPF) polymer, an ultra-short single-walled carbon nanotube (US-tube) nanocomposite, and a dodecylated US-tube (F-US-tube) nanocomposite] in order to evaluate the effects of material composition and porosity on scaffold pore structure, mechanical properties, and marrow stromal ...

Ultrasonic-assisted tungsten inert gas welding was carried out on a thin plate of 2195 Al-Li alloy, and the characteristics of the weld pores were analyzed in terms of their size and porosity. The effects of welding speed and ultrasonic power on the porosity and size of the pores were investigated. The pores were found to occur primarily adjacent to the surface of the weld. The porosity decreas...

INTRODUCTION The porosity of the fibrous capsule around a glaucoma drainage device (GDD) may be the most important functional attribute. The factors that determine capsular porosity are not well understood. Failed GDD surgeries are usually associated with thick impervious capsules and components of aqueous have been implicated in this process. PURPOSE In this study, we interrogated the effect...

A novel modeling technique for porous tissue scaffolds with targeting the functionally gradient variational porosity with continuous material deposition planning has been proposed. To vary the porosity of the designed scaffold functionally, medial axis transformation is used. The medial axis of each layers of the scaffold is calculated and used as an internal feature. The medial axis is then us...