## THERMAL SCIENCE

International Scientific Journal

### LATTICE BOLTZMANN SIMULATION OF RAYLEIGH-BENARD CONVECTION IN ENCLOSURES FILLED WITH AL2O3-WATER NANOFLUID

**ABSTRACT**

In order to clarify the controversies for the role of nanoparticles on heat transfer in natural convection, lattice Boltzmann method is used to investigate Rayleigh-Benard convection heat transfer in differentially-heated enclosures filled with Al2O3-water nanofluids. The results for streamline and isotherm contours, vertical velocity, and temperature profiles as well as the local and average Nusselt number are discussed for a wide range of Rayleigh numbers and nanoparticle volume fractions (0 ≤ Ф ≤ 5%). The results show that with the increase of Rayleigh number and nanoparticles loading, Nuave increases. It is suggested that the addition of nanoparticles can enhance the heat transfer in Rayleigh-Benard convection.

**KEYWORDS**

PAPER SUBMITTED: 2017-10-23

PAPER REVISED: 2017-11-23

PAPER ACCEPTED: 2017-11-23

PUBLISHED ONLINE: 2018-02-18

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**Supplement 2**, PAGES [S535 - S545]

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