Impact of multi-phase flow of hybrid nanofluid on mixed convection inside the square cavity with partially heated wall

A numerical study has been undertaken for the mixed convection (MC) of a hybrid-nanofluid comprised of Al2O3 and Cu nanoparticles with water as the base fluid filled in square cavity containing a rotating cylinder. The Brownian and thermophoresis effects given in Buongiorno's model are applied for the two-phase flow. A section of the left wall is heated, while the other portion stays adiabatic. In addition, the rotating cylinder is heated to the same temperature as the partially heated wall, and the right wall is maintained at a constant cold temperature. The upper and lower walls are kept adiabatic. The Rayleigh number, nano-particle loading, and dimensionless radius of the rotating cylinder are assumed in the ranges of 10^3 ≤ Ra ≤ 10^5, 0 ≤ Φ ≤ 0.04, 0.1 ≤ R ≤ 0.4, respectively. The dimensionless governing equations are developed and solved using Galerkin's weighted residual method. The variation of streamlines, the average nano-particle loading, and the temperature distribution are discussed. The results show that enhancement in convective heat transfer corresponding to the rise in Rayleigh number. The enhanced convective heat transfer at higher Rayleigh numbers opens the possibilities for improvement in performance of hybrid-nanofluid filled enclosures.