Izotermiczny ściśliwy jednofazowy przepływ cieczy przez niejednorodną masę ziarnistą składającą się z gęsto upakowanych zachodzących na siebie kul imitujących skałę pod wysokim ciśnieniem zbadano numerycznie przy użyciu dwóch różnych podejść. Pierwsze podejście zwane pełnym modelem 3D CFD stosowało metodę skończonych objętości (FVM) do rozwiązania uśrednionego równania Naviera-Stokesa zakładając model naprężeń Reynoldsa (BSL) w...

A one-dimensional problem of a spherical cavity expanding at a constant velocity from zero initial radius in an infinite granular medium, which has the first-kind self-similar solution, is considered. We are solving this dynamic spherical cavity-expansion problem to model rigid spheres penetrating into a granular media. Elastic–plastic deformation of the granular media is described in a barotropic approximation, using the high-pressure...

Discrete Element Method is a numerical method suitable for modeling geotechnical problems concerning granular media. In most cases simple forms of grains, like discs or spheres, are used. But these shapes are capable of soil behavior modeling up to a certain point only, they cannot reflect all of the features of the medium (large shear resistance and large volumetric change). In order to reflect the complex behavior of the real...

Nowadays, occurrence of abnormal mineral or organic natural (geogenic) compounds concentrations, in ground and infiltration water, but also quite often in surface waters, is now a common problem encountered in Poland, Europe and many other countries throughout the world. The most concern is usually paid on the removal of iron (Fe) and manganese (Mn) as well as anthropogenic compounds (in particular referring to the organic compounds...

The anammox-enriched granular sludge was successfully formed during the long-term biogranulation experiment lasting over 330 days. The cultivation was conducted at 30 ◦C in a 10-L sequencing batch reactor (SBR) fed with synthetic medium containing ammonia, nitrite and trace elements. The properties of the developed granules were investigated in terms of the biomass activity (including the growth rate of anammox bacteria), size...