Marangoni convection in a hybrid nanofluid-filled cylindrical annular enclosure with sinusoidal temperature distribution

Abstract: The current research numerically investigates the Marangoni convection in a cylindrical annulus filled with hybrid nanofluid saturated porous media. The interior and exterior walls are subjected to spatially varying sinusoidal thermal distributions with various amplitude ratios and phase deviations. The limits at the top and bottom are adiabatic. To solve the system of non-dimensional governing equations, the finite difference approach is applied. The main objective of the ongoing study is to investigate the impact of the Marangoni number, nanoparticle volume fraction and the radii ratio on the amplitude ratio and phase deviation. Also, the fluid flow, thermal characteristics, local and average Nusselt numbers are analysed in the hybrid nanofluid-filled vertical cylindrical annulus with magnetic effects. The findings indicate that the sinusoidal temperature promotes multicellular flow in the porous annular region. In the annulus with sinusoidal boundaries, the Marangoni number underperforms while the nanoparticle volume fraction outperforms. Graphic abstract: [Figure not available: see fulltext.].