## THERMAL SCIENCE

International Scientific Journal

### NUMERICAL INVESTIGATION OF THE EFFECT OF THE INSULATION THICKNESS ON THE DEGREE OF NONUNIFORMITY OF THE BILLET TEMPERATURE

**ABSTRACT**

The degree of nonuniformity of the billet temperature subjected to the radiative heat loss to the discharge door with different insulation thicknesses is investigated in this present study. The 2-D steady-state heat conduction for the billet subjected to different heat fluxes is solved by being transformed into a dimensionless form. The Gauss-Seidel iterative method for a finite volume discretization of the billet is employed to obtain the temperature distribution of the billet. The numerical result is validated by comparing with the field measurement data. A qualitative agreement between these two is observed. An effect of different insulation thicknesses on the heat-transfer characteristics and the degree of nonuniformity of the billet temperature is examined. In case of the replaced 50-mm thick insulation of the discharge door, the radiative heat loss to the discharge door is reduced by 49% with the replaced insulation, and the degree of nonuniformity of the billet temperature is decreased by 23°C.

**KEYWORDS**

PAPER SUBMITTED: 2012-04-19

PAPER REVISED: 2014-06-11

PAPER ACCEPTED: 2014-07-18

PUBLISHED ONLINE: 2014-08-03

**THERMAL SCIENCE** YEAR

**2015**, VOLUME

**19**, ISSUE

**3**, PAGES [1097 - 1105]

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