NUMERICAL INVESTIGATION OF BUOYANCY DRIVEN HEAT TRANSFER OF WATER-BASED CuO NANOFLUIDS IN A RECTANGULAR ENCLOSURE WITH AN OFFCENTER SOLID CONDUCTING BODY

Öz

In this study, buoyancy driven heat transfer of water-based CuO nanofluid in a rectangular enclosure with a solid cylinder was investigated numerically for different values of aspect ratio, location and diameter of solid cylinder, solid volume fraction and Rayleigh number. While bottom and upper walls of enclosure are adiabatic, sidewalls are isothermal. Thermal conductivity of solid cylinder was assumed to be equal to that of the base fluid. Governing equations were solved numerically by Comsol Multiphysics finite element modeling and simulation software. Results show that heat transfer rate increases considerably with an increase in the Rayleigh number and solid volume fraction and with a decrease in the solid cylinder diameter. Results also show that heat transfer rate shows an increase with an increase of aspect ratio for low values of Rayleigh number. Finally, results show that heat transfer rate gets its highest value for square enclosure case for high values of Rayleigh number.

Anahtar Kelimeler

• Nanofluid,Enclosure

Kaynakça

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