MHD natural convection of a hybrid nanofluid in an enclosure with multiple heat sources

Abstract

Natural convective flow and heat transfer of a hybrid nanofluid contained in an enclosure with multiple heat sources at the bottom wall are investigated in the presence of magnetic field applied to an angle with the horizontal axis. The system of equations is formulated systematically using dimensionless variables and parameters as well as defining stream function in terms velocity components. Solutions obtained by the finite difference method are then validated with experimental and numerical results which provides a good agreement. A grid independent test is also performed. Results reveal that flow pattern is substantially changed with the change of the magnetic field parameter, angle of magnetic field, number and breadth of heat sources and Rayleigh number. The intensity of the stream function is stronger for higher Rayleigh number and smaller magnetic field parameter. When the volume fraction of Cu nanoparticles is more than 6% the streamlines and isotherms demonstrate distinct pattern from those for its lower value. Moreover, symmetric pattern of streamlines is observed for angle of magnetic field equal to 0 and π/2. Due to the increase of the number of heat sources, angle of magnetic field and Rayleigh number, average Nusselt number is found to increase.

Keywords

• Natural convection
• Hybrid nanofluid
• Multiple heat sources
• Magnetic field