## THERMAL SCIENCE

International Scientific Journal

### MIXED CONVECTION HEAT TRANSFER FROM A PARTICLE IN SUPERCRITICAL WATER

**ABSTRACT**

This paper aims to study a steady laminar convection flow over a spherical particle in supercritical water in pseudo-critical zone. Forced convection, free convection, assisting convection, and opposing convection from a spherical particle in supercritical water (SCW) were studied based on a numerical model fully accounting for variations of thermo-physical properties in pseudo-critical zone. Variation of specific heat plays a main role in determination of heat transfer coefficient. The gravity direction has a remarkable effect on heat transfer. Quantitative relationship between variable properties and Nusselt number has been established based on the simulation results.

**KEYWORDS**

PAPER SUBMITTED: 2013-11-03

PAPER REVISED: 2014-01-20

PAPER ACCEPTED: 2014-03-03

PUBLISHED ONLINE: 2014-04-05

**THERMAL SCIENCE** YEAR

**2016**, VOLUME

**20**, ISSUE

**2**, PAGES [483 - 492]

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