Effect of the structural parameters changes in the multi-strand tundish on the non-metallic inclusions distribution and separation

The aim of presented studies was to investigate the fluid flow change and non-metallic inclusions removal changes due to tundish construction modifications. In presented study, numerical simulations were used. Numerical simulations are carried out with the finite-volume commercial code ANSYS Fluent. Steady-state casting conditions for the flow structure and the inclusions removal process are analysed

Analysis of liquid steel flow in a multi-strand tundish using numerical methods

The article presents the results of liquid steel flow and mixing in tundish when applying turbulence inhibitor to modernize the tundish working zone. The flow of six-strand continuous casting tundish of a trough-type was investigated with numerical modeling. For turbulence modeling, the Reynolds-Averaged Navier-Stokes (RANS) equation and the Large Eddy Simulation (LES) methods have been used. Numerical simulations are carried out with the finitevolume commercial code AnsysFluent

Validation of numerical model of a liquid flow in a tundish by laboratory measurements

The article presents results of physical and numerical modelling of steel flow through a tundish of continuous casting machine. In numerical calculations the influence of mesh density was tested and the correctness of the flow description in the near-wall region was checked using Standard Wall Function model. Obtained results were verified using experimental results of velocity field (PIV method) coming from a water tundish model

Non-metallic inclusions controling at the ladle furnace (LF) station

The article contains the results of research performed on the determination of the quantity and morphology of nonmetallic inclusions identified at the secondary metallurgy process during the cold-swelling steel production. Continuous improvement of steel quality standards, which today is primarily associated with the amount of inclusions contained in the steel product, enforces actions taken to remove the largest possible number of inclusions from steel and/or by their modification at the final stage of secondary metallurgy processing. Therefore, research was undertaken at the ladle furnace industrial stand, and the steel samples were subjected to metallographic testing. It was shown that the number and/or the size of inclusions identified in the samples taken at the beginning and end of the process decreased, and in addition they were modified

Depression and religiosity in older age

We investigated the hypothesis that religious commitment could help counter general affective distress, accompanying depressive symptoms, in older age. A total of 34 older adults, all catholic believers, completed self-reported questionnaires on the presence of depressive symptoms, religiosity, health, worry, and the style of coping with stress. The depressive and non-depressive subgroups were then created. The prevalence of depressive symptoms was 50%, with the substantial predominance of females. Regression analyses indicate that health expectations and worry significantly worsen with increasing intensity of depressive symptoms. The results further show that religious engagement was not different between the depressive and non-depressive subgroups. Religiosity failed to influence the intensity of depressive symptoms or the strategy of coping with stress in either subgroup, although a trend was noted for better health expectations with increasing religious engagement in depressive subjects. We conclude that religiosity is unlikely to significantly ameliorate dysphoric distress accompanying older age

Differential Algebras in Non-Commutative Geometry

We discuss the differential algebras used in Connes' approach to Yang-Mills theories with spontaneous symmetry breaking. These differential algebras generated by algebras of the form functions $\otimes$ matrix are shown to be skew tensorproducts of differential forms with a specific matrix algebra. For that we derive a general formula for differential algebras based on tensor products of algebras. The result is used to characterize differential algebras which appear in models with one symmetry breaking scale.Comment: 21 page

Numeričko modeliranje protjecanja metala u međuloncu sa šest žila pomoću različitih uređaja za kontrolu protjecanja

Numerical modelling have been extensively used to study the fluid flow phenomena taking place in continuous casting tundish. The paper presents the results of steel flow researches done on tundishs with a capacity of 22 Mg, with different flow control devices. The tundish is a “trough”-type designed for the continuous casting of slabs intended for small cross-section rolled products. In effect of mathematical calculations liquid steel velocity, turbulence intensity, turbulent kinetic energy and temperature distributions have been obtained. Calculations were passed by commercial computer program FLUENT.Numeričko modeliranje široko se primjenjuje za proučavanje fenomena protjecanja fluida koji se odvija u međuloncu uređaja za kontinuirano lijevanje. U članku su prezentirani rezultati istraživanja protjecanja čelika u međuloncima kapaciteta 22 Mg, s različitim uređajima za kontrolu protjecanja. Međulonac je "koritastog" tipa, a namijenjen je za kontinuirano lijevanje slabova za valjane proizvode malog poprečnog presjeka. Matematičkim proračunima dobije se brzina tekućeg čelika, intenzitet turbulencije, turbulentna kinetička energija i temperaturna raspodjela. Proračuni su provedeni na komercijalnom računalnom programu FLUENT

Numerical and experimental analysis of vortex sheets behind lifting surfaces

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77273/1/AIAA-1992-409-534.pd

Numeričko modeliranje protjecanja metala u međuloncu sa šest žila pomoću različitih uređaja za kontrolu protjecanja

Numerical modelling have been extensively used to study the fluid flow phenomena taking place in continuous casting tundish. The paper presents the results of steel flow researches done on tundishs with a capacity of 22 Mg, with different flow control devices. The tundish is a “trough”-type designed for the continuous casting of slabs intended for small cross-section rolled products. In effect of mathematical calculations liquid steel velocity, turbulence intensity, turbulent kinetic energy and temperature distributions have been obtained. Calculations were passed by commercial computer program FLUENT.Numeričko modeliranje široko se primjenjuje za proučavanje fenomena protjecanja fluida koji se odvija u međuloncu uređaja za kontinuirano lijevanje. U članku su prezentirani rezultati istraživanja protjecanja čelika u međuloncima kapaciteta 22 Mg, s različitim uređajima za kontrolu protjecanja. Međulonac je "koritastog" tipa, a namijenjen je za kontinuirano lijevanje slabova za valjane proizvode malog poprečnog presjeka. Matematičkim proračunima dobije se brzina tekućeg čelika, intenzitet turbulencije, turbulentna kinetička energija i temperaturna raspodjela. Proračuni su provedeni na komercijalnom računalnom programu FLUENT

Mješanje i kemijska homogenizacija taline čelika u 100-tonskom livnom loncu

The article presents numerical simulations of fluid flow and chemical homogenization of liquid steel in gas-stirred ladle with two asymmetric porous plugs. In this study mixing time is analyzed as a function of porous plug location. All calculations were carried out by commercial computer program Fluent using k-ε turbulence model. Results show the velocity vectors of liquid steel and tracer concentration field after alloy addition. Numerical calculations were used to get the mixing time of liquid steel as a function of gas flow rate and porous plugs location.Članak predstavlja numeričke simulacije tijeka tekućine i kemijske homogenizacije tekućeg čelika u loncu s miješanjem plina pomoću asimetrično postavljenih poroznih čepova. U ovoj se studiji vrijeme miješanja analizira kao funkcija položaja poroznog čepa. Svi su izračuni provedeni pomoću komercijalnog računalskog programa Fluent koristeći k- ε modele turbulencije. Rezultati pokazuju vektore brzine tekućeg čelika i polje koncentracije obilježenih indikatora nakon dodavanja legure. Numerički su proračuni upotrijebljeni za dobivanje vremena miješanja tekućeg čelika kao funkcije brzine toka plina i položaja poroznog čep