Detail publikace

A (non-)hydrostatic free-surface numerical model for two-layer flows

BOHÁČEK, J. KHARICHA, A. LUDWIG, A. WU, M. KARIMI-SIBAKI, E. PAAR, A. BRANDER, M. ELIZONDO, L. TRICKL, T.

Anglický název

A (non-)hydrostatic free-surface numerical model for two-layer flows

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

en

Originální abstrakt

A semi-implicit (non-) hydrostatic free-surface numerical model for two layer flows is derived from the Navier-Stokes equations by applying kinematic boundary conditions at moving interfaces and by decomposing the pressure into the hydrostatic and the hydrodynamic part. When the latter is ignored, the algorithm conveniently transforms into a solver for a hydrostatic flow. In addition, when the vertical grid spacing is larger than the layer depths, the algorithm naturally degenerates into a solver for the shallow water equations. In this paper, the presented numerical model is developed for the horizontal centrifugal casting, a metallurgical process, in which a liquid metal is poured into a horizontally rotating cylindrical mold. The centrifugal force pushes the liquid metal toward the mold wall resulting in a formation of a sleeve with a uniform thickness. The mold gradually extracts the sensible and the latent heat from the sleeve, which eventually becomes solid. Often a second layer of another material is introduced during the solidification of the first layer. The proposed free-surface model is therefore coupled with the heat advection-diffusion equation with a stiff latent heat source term representing the solidification. The numerical results show a good agreement with measurements of temperatures performed in the plant. A validation of the proposed model is also provided with the help of using other numerical techniques such as the approximate Riemann solver for the two layer shallow water equations and the volume of fluid method. (C) 2017 Elsevier Inc. All rights reserved.

Anglický abstrakt

A semi-implicit (non-) hydrostatic free-surface numerical model for two layer flows is derived from the Navier-Stokes equations by applying kinematic boundary conditions at moving interfaces and by decomposing the pressure into the hydrostatic and the hydrodynamic part. When the latter is ignored, the algorithm conveniently transforms into a solver for a hydrostatic flow. In addition, when the vertical grid spacing is larger than the layer depths, the algorithm naturally degenerates into a solver for the shallow water equations. In this paper, the presented numerical model is developed for the horizontal centrifugal casting, a metallurgical process, in which a liquid metal is poured into a horizontally rotating cylindrical mold. The centrifugal force pushes the liquid metal toward the mold wall resulting in a formation of a sleeve with a uniform thickness. The mold gradually extracts the sensible and the latent heat from the sleeve, which eventually becomes solid. Often a second layer of another material is introduced during the solidification of the first layer. The proposed free-surface model is therefore coupled with the heat advection-diffusion equation with a stiff latent heat source term representing the solidification. The numerical results show a good agreement with measurements of temperatures performed in the plant. A validation of the proposed model is also provided with the help of using other numerical techniques such as the approximate Riemann solver for the two layer shallow water equations and the volume of fluid method. (C) 2017 Elsevier Inc. All rights reserved.

Klíčová slova anglicky

numerical modeling; free-surface model; centrifugal casting; solidification; advection-diffusion equation; shallow water equations

Vydáno

15.02.2018

Nakladatel

ELSEVIER SCIENCE INC

Místo

NEW YORK

ISSN

0096-3003

Ročník

319

Číslo

1

Strany od–do

301–317

Počet stran

17

BIBTEX


@article{BUT164742,
  author="Jan {Boháček} and Ebrahim {Karimi-Sibaki},
  title="A (non-)hydrostatic free-surface numerical model for two-layer flows",
  year="2018",
  volume="319",
  number="1",
  month="February",
  pages="301--317",
  publisher="ELSEVIER SCIENCE INC",
  address="NEW YORK",
  issn="0096-3003"
}