## THERMAL SCIENCE

International Scientific Journal

### NUMERICAL STUDY OF NATURAL MELT CONVECTION IN CYLINDRICAL CAVITY WITH HOT WALLS AND COLD BOTTOM SINK

**ABSTRACT**

Numerical study of natural convection heat transfer and fluid flow in cylindrical cavity with hot walls and cold sink is conducted. Calculations are performed in terms of the cavity aspect ratio, the heat exchanger length and the thermo physical properties expressed via the Prandtl number and the Rayleigh number. Results are presented in the form of isotherms, streamlines, average Nusselt number and average bulk temperature for a range of Rayleigh number up to 106. It is observed that Rayleigh number and heat exchanger length influences fluid flow and heat transfer, whereas the cavity aspect ratio has no significant effects.

**KEYWORDS**

PAPER SUBMITTED: 2011-03-27

PAPER REVISED: 2012-09-20

PAPER ACCEPTED: 2012-09-25

**THERMAL SCIENCE** YEAR

**2013**, VOLUME

**17**, ISSUE

**3**, PAGES [853 - 864]

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