### Abstract

Magnetic fields are used extensively to direct liquid metal flows in material processing. Continuous casting of steel uses different configurations of magnetic fields to optimize turbulent flows in rectangular cross-sections to minimize defects in the solidified steel product. Realizing the importance of a magnetic field on turbulent flows in rectangular cross-sections, the present work is aimed at understanding the effect of a magnetic field on the turbulent metal flow at a nominal bulk Reynolds number of ∼5300 (based upon full duct height) (Re. _{τ}= 170, based upon half duct height) and Hartmann numbers (based upon half duct height) of 0, 6.0 and 8.25 in a 2:1 aspect ratio rectangular duct. Direct numerical simulations in a non-MHD 2:1 aspect ratio duct followed by simulations with transverse and span-wise magnetic fields have been performed with 224 × 120 × 512 cells (∼13.7 million cells). The fractional step method with second order space and time discretization schemes has been used to solve the coupled Navier-Stokes-MHD equations. Instantaneous and time-averaged natures of the flow have been examined through distribution of velocities, various turbulence parameters and budget terms. Spanwise (horizontal) magnetic field reorganizes and suppresses secondary flows more strongly. Turbulence suppression and velocity flattening effects are stronger with transverse (vertical) magnetic field.

Original language | English (US) |
---|---|

Pages (from-to) | 100-114 |

Number of pages | 15 |

Journal | Computers and Fluids |

Volume | 51 |

Issue number | 1 |

DOIs | |

State | Published - Dec 15 2011 |

### Fingerprint

### Keywords

- DNS
- MHD
- Rectangular duct
- Turbulent flow

### ASJC Scopus subject areas

- Computer Science(all)
- Engineering(all)

### Cite this

*Computers and Fluids*,

*51*(1), 100-114. https://doi.org/10.1016/j.compfluid.2011.08.002

**Direct numerical simulations of transverse and spanwise magnetic field effects on turbulent flow in a 2:1 aspect ratio rectangular duct.** / Chaudhary, R.; Shinn, A. F.; Vanka, Surya Pratap; Thomas, B. G.

Research output: Contribution to journal › Article

*Computers and Fluids*, vol. 51, no. 1, pp. 100-114. https://doi.org/10.1016/j.compfluid.2011.08.002

}

TY - JOUR

T1 - Direct numerical simulations of transverse and spanwise magnetic field effects on turbulent flow in a 2:1 aspect ratio rectangular duct

AU - Chaudhary, R.

AU - Shinn, A. F.

AU - Vanka, Surya Pratap

AU - Thomas, B. G.

PY - 2011/12/15

Y1 - 2011/12/15

N2 - Magnetic fields are used extensively to direct liquid metal flows in material processing. Continuous casting of steel uses different configurations of magnetic fields to optimize turbulent flows in rectangular cross-sections to minimize defects in the solidified steel product. Realizing the importance of a magnetic field on turbulent flows in rectangular cross-sections, the present work is aimed at understanding the effect of a magnetic field on the turbulent metal flow at a nominal bulk Reynolds number of ∼5300 (based upon full duct height) (Re. τ= 170, based upon half duct height) and Hartmann numbers (based upon half duct height) of 0, 6.0 and 8.25 in a 2:1 aspect ratio rectangular duct. Direct numerical simulations in a non-MHD 2:1 aspect ratio duct followed by simulations with transverse and span-wise magnetic fields have been performed with 224 × 120 × 512 cells (∼13.7 million cells). The fractional step method with second order space and time discretization schemes has been used to solve the coupled Navier-Stokes-MHD equations. Instantaneous and time-averaged natures of the flow have been examined through distribution of velocities, various turbulence parameters and budget terms. Spanwise (horizontal) magnetic field reorganizes and suppresses secondary flows more strongly. Turbulence suppression and velocity flattening effects are stronger with transverse (vertical) magnetic field.

AB - Magnetic fields are used extensively to direct liquid metal flows in material processing. Continuous casting of steel uses different configurations of magnetic fields to optimize turbulent flows in rectangular cross-sections to minimize defects in the solidified steel product. Realizing the importance of a magnetic field on turbulent flows in rectangular cross-sections, the present work is aimed at understanding the effect of a magnetic field on the turbulent metal flow at a nominal bulk Reynolds number of ∼5300 (based upon full duct height) (Re. τ= 170, based upon half duct height) and Hartmann numbers (based upon half duct height) of 0, 6.0 and 8.25 in a 2:1 aspect ratio rectangular duct. Direct numerical simulations in a non-MHD 2:1 aspect ratio duct followed by simulations with transverse and span-wise magnetic fields have been performed with 224 × 120 × 512 cells (∼13.7 million cells). The fractional step method with second order space and time discretization schemes has been used to solve the coupled Navier-Stokes-MHD equations. Instantaneous and time-averaged natures of the flow have been examined through distribution of velocities, various turbulence parameters and budget terms. Spanwise (horizontal) magnetic field reorganizes and suppresses secondary flows more strongly. Turbulence suppression and velocity flattening effects are stronger with transverse (vertical) magnetic field.

KW - DNS

KW - MHD

KW - Rectangular duct

KW - Turbulent flow

UR - http://www.scopus.com/inward/record.url?scp=80053244312&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80053244312&partnerID=8YFLogxK

U2 - 10.1016/j.compfluid.2011.08.002

DO - 10.1016/j.compfluid.2011.08.002

M3 - Article

VL - 51

SP - 100

EP - 114

JO - Computers and Fluids

JF - Computers and Fluids

SN - 0045-7930

IS - 1

ER -