Wyniki wyszukiwania - BazTech

1

Entropijny model rozkładu prędkości ziaren w pionowym klasyﬁkatorze grawitacyjnym

Otwinowski H.

Inżynieria i Aparatura Chemiczna

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2013

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Nr 3

222--223

PL

W artykule przedstawiono modelowanie rozkładu prędkości ziaren w kolumnie pionowego klasyﬁkatora grawitacyjnego przy wykorzystaniu zasady maksymalizacji entropii informacyjnej. Zagadnienie wariacyjne z dwoma warunkami dodatkowymi rozwiązano metodą mnożników Lagrange’a. Adekwatność modelu potwierdziły wyniki eksperymentalnej weryﬁkacji na podstawie pomiarów prędkości ziaren elektrokorundu w pionowej kolumnie układu z cyrkulacyjną warstwą ﬂuidalną.

EN

Modeling of particle velocity distribution in a vertical column of gravitational classifier using the maximum informational entropy principle is presented in the paper. Variational problem with two additional conditions was solved using the Lagrange multipliers method. Results of experimental verification confirmed the model adequacy. Verification was carried out by the measurement of velocity of electrocorundum particles in a vertical column with the circulating fluidized bed.

2

Influence of bed particle size on gas-powder two phase flow conditions in descending packed bed. Model investigation (3D physical model)

Panic B.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

567--572

EN

Purpose: The aim of the research is to create basis for introduction of mathematical model for two phase flow in descending packed bed. Design/methodology/approach: Iron obtaining from ore in shaft furnace is connected with accumulation of small particles inside the furnace, which can cause increased gas flow resistance. It is important that no flow disturbances occur. Hence researches were conducted to model (construction of 3D physical model) the flow of gas with powder through two bed types. Findings: Intense accumulation of both powder fractions at the bottom of the bed was noted. Between analysed bed types, a large radial diversification of static pressure has been revealed occurring on the nozzles level. Two reasons of such diversification were identified. Research limitations/implications: Radial changes of static pressure and gas flow resistance along bed height were registered (physical model 3D). Radial distribution of analysed bed was investigated. Amount of powder accumulated in bed was measured with division on “dynamic” and “static” powder. 2D models provide excellent visualization of the occurring phenomena. In full 3D visualization is much more difficult but they mirror real conditions in a better way. Next stage of the research will be conducted with real materials. Practical implications: The developed calculation procedure could be used in flow and its disturbances evaluation in real shaft metallurgical units. Originality/value: In 3D model “static” powder (with its radial distribution) at the tuyere level and in the higher part of bed was measured.

3

Badania modelowe rozkładu cząstek złoża w reaktorach szybowych

Panic B.

Hutnik, Wiadomości Hutnicze

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2011

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Vol. 78, nr 9

710--712

PL

Celem rozpoczętych badań jest opracowanie podstaw dla zaproponowania modelu matematycznego przepływu dwufazowego gaz– pył przez schodzące złoże kawałkowe z uwzględnieniem radialnego rozkładu przepływu. Dla ich realizacji zaprojektowano i skonstruowano model fizyczny przepływu dwufazowego gaz–pył przez ruchome (schodzące) złoże kawałkowe. Przy konstruowaniu modelu fizycznego uwzględniono kryteria Reynoldsa i Froude’a. Przeprowadzone dotąd badania doprowadziły do identyfikacji trzech stref, które występują podczas przepływu cząstek złoża w reaktorze: strefy przepływu laminarnego, strefy przepływu kominowego, strefy stagnacji. Czynnikiem różnicującym prędkość schodzących cząstek jest tarcie o ściany reaktora oraz wpływ strefy stagnacji.

EN

The purpose of this study was to work out the basis for mathematical model of gas-powder two phase flow in descending bed, taking into consideration radial distribution of flow. To realize this purpose physical model of gas-powder two phase flow with descending bed was projected and constructed. Reynolds and Froude criterions were taking into consideration. Three zones connected with bed particle flow were identified in reactor: zone of laminar flow, funnel zone and stagnant zone (deadman). Wall friction and stagnant zone are the factors differentiating velocity of bed descending particles.

4

Energy spectrum of turbulence in the gas-solid flow

Poria S., Mazumdar H. P.

Journal of Technical Physics

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2007

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Vol. 48, no 1

3-11

EN

In this paper, we have derived several self-preserving turbulence energy spectra for the case of a homogeneous, isotropic, particle-laden turbulent flow, assuming different forms for the energy transfer spectra, as those obtained from the general form for such a transfer spectrum due to TENNEKES [10] and YAGLOM [11]. All these self-preserving turbulence energy spectra are then analyzed from the view-point that the turbulence is affected by the particles in a homogeneous isotropic, particle-laden turbulent flow.

5

Analiza obrazu w badaniach przpływu mieszanin gaz - ciało stałe

Anweiler S., Szmolke N.

Inżynieria i Aparatura Chemiczna

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2004

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Nr 3s

7-8

EN

Usability of image recognition method for two-phase gas-solid flow research has been presented in this work. Significant attributes of this method have been brought to attention and practical aspects indicated.