Natural convection analysis employing entropy generation and heatline visualization in a hollow L-shaped cavity filled with nanofluid using lattice Boltzmann method- experimental thermo-physical properties

The natural convection heat transfer and fluid flow is analyzed using lattice Boltzmann numerical method. The entropy generation analysis and heatline visualization are used to study the convective flow field comprehensively. The hollow L-shaped cavity is considered and filled with SiO2-TiO2/Water-EG ( 60: 40) hybrid nanofluid. The thermal conductivity and dynamic viscosity of nanofluid are measured experimentally. To use the experimental data of thermal conductivity and dynamic viscosity, two sets of correlations based on temperature for six different solid volume fractions of 0.5, 1, 1.5, 2, 2.5 and 3 vol% are derived. The influences of different governing parameters such different aspect ratios, solid volume fractions of nanofluid and Rayleigh numbers on the fluid flow, temperature filed, average/local Nusselt number, total/local entropy generation and heatlines are presented.