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Journal of Sustainable Metallurgy

, Volume 5, Issue 2, pp 195–203 | Cite as

CFD Modeling of Melt Spreading Behavior on Spinning Discs and Cups for Centrifugal Granulation of Molten Slag

  • Yuhua PanEmail author
  • Ming Zhao
  • Ping Ma
  • Jing Li
  • Zhaoyi Huo
  • Hongyu Li
Thematic Section: Slag Granulation
Part of the following topical collections:
  1. Slag Granulation

Abstract

The spreading behaviors of molten slag on spinning discs and cups were studied through performing free surface flow numerical simulations by means of computational fluid dynamics (CFD) modeling technique. In this work, liquid slag film thickness at the edge of the spinning discs and cups was predicted by using the CFD model, since the slag film thickness has a predominant influence on the size of the slag granules produced after the slag film breakup. The effects of the shape of discs and cups and the operating conditions (slag flowrate and spinning speed) on the slag film thickness were examined. Flat surface disc, disc with curved surface, and cups with different sidewall height and taper angle were investigated. It was found from the modeling results that, under the same slag flowrate and spinning speed, the larger the wetting area of the slag on the discs and cups, the smaller the slag film thickness. For the same size (radius) discs and cups, the slag film thickness on the flat surface disc is larger than those on the cup and the curved surface disc. Furthermore, the film thickness on the cup is larger than that on the curved surface disc. The reason is that the cup has a sharp corner and a sidewall that impose a larger resistance to the slag flow, whereas the curved surface disc has a smooth surface that has a smaller resistance to the slag flow.

Keywords

Centrifugal granulation Spinning disc Spinning cup Molten slag Film thickness Free surface flow 

Nomenclature

Alphabetic Symbols

Cμ

Constant in turbulence model

F

Body force vector

F1

First blending function in turbulence model

H

Depth of curved surface disc and cup

k

Turbulence kinetic energy

Np

Total number of fluid phases (Np = 2 for liquid slag and air)

p

Pressure

Pk

Production rate of turbulence kinetic energy

r

Volume fraction

R

Radius of disc and cup

u

Velocity vector

Greek Symbols

α3

Constant in turbulence model

β′

Constant in turbulence model

β3

Constant in turbulence model

ε

Dissipation rate of turbulence kinetic energy

κ

Local curvature of free surface

μ

Dynamic viscosity

μt

Turbulent viscosity

θ

Taper angle of cup sidewall

ρ

Density

σω2

Prandtl number for ω in transformed k-ε model

σω3

Prandtl number for ω in SST turbulence model

σk3

Prandtl number for k in SST turbulence model

ω

Turbulence eddy frequency

Subscripts

α

Fluid phase identity (liquid slag or air)

g

Gas phase or gravitational force

l

Liquid phase

s

Surface tension force

Notes

Acknowledgements

The present work was financially supported by Education Department of Liaoning Province (Grant No.: 2017LNQN17), China, and University of Science and Technology Liaoning (Grant No.: 2016QN19), China.

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.School of Materials and MetallurgyUniversity of Science and Technology LiaoningAnshanChina

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