Numerical investigation of hybrid nanofluid flow in a lid driven cavity with a heated obstacle

Abstract

This study aims to examine heat transfer and fluid flow around a heated solid obstacle in a lid-driven cavity filled with a hybrid TiO2-Cu/water nanofluid. The geometry being analyzed is a two-dimensional cavity with an aspect ratio of 5. The upper wall moves at a constant velocity of Ulid. The solid obstacle connected to the bottom wall of the cavity is kept at a higher temperature than the top and lower walls, while the remaining walls are insulated. The hybrid nanofluid flow is considered to be Newtonian, laminar, and incompressible. The Richardson number's impact is analyzed by keeping the Reynolds number constant at 100 and adjusting the Grashof number from 102 to 104. The volume fractions of each nanoparticles range from 0% to 8%. The results are presented in terms of streamlines, isotherms, and profiles of the average Nusselt number. Numerical data indicates that cells rotating in opposite directions are formed inside the rectangular container as a result of the combined influence of natural and forced convection. Increasing the Richardson number from 0.01 to 1, due to heightened buoyancy effect, results in a 4.5% increase in the Nusselt number. An increase of 8% in the volume percentage of nanoparticles for each Richardson number results in a heat transfer rate enhancement of around 9.8%.