Numerical Examination of a Cavity Containing Nanofluid with an Upper Oscillating Wall and Baffle

The cavity with lid-driven is greatly used in mixing, coating, and drying applications and is a substantial issue in the study of thermal performance rate and fluid field. A numerical approach is presented to study the thermal distribution and passage of fluid in a lid-driven cavity with an upper oscillating surface and an attached baffle. The walls of a cavity at the left and right were maintained at 350 and 293 K, respectively. The upper oscillating surface was equipped with a variable height to baffle to increase the convection of the three kinds of TiO₂, Al₂O₃, and CuO nanofluids with various of 0.4, 0.8, and 0.4, 0.8, and 1.2 vol. % in volume fractions. It was found that using a baffle attached to the oscillating upper surface of the cavity will lead to improving the distribution of vorticity in the cavity and increase the stream in the cavity. Also, increasing the baffle height, oscillating velocity, and volume fraction of nanoparticles contributes to enhancing the Nusselt number values by 50% for increasing baffle height from h^* = 0.1 to 0.1. Also, the Nu improved by 20% for increasing oscillating velocity from w = 05 to 20 rad/s and by 12% for using Al₂O₃ nanofluid instead of TiO₃ at $\mathrm{\phi }$ = 0.8 vol. %.