Solidification of nano-enhanced phase change material (NEPCM) in a wavy cavity

The effects of surface waviness (lambda = 0, 0.125, 0.25, 0.5) and nanoparticle dispersion (I center dot = 0, 0.05, 0.1) on solidification of Cu-water nanofluid inside a vertical enclosure are investigated numerically for different Grashof number (Gr = 10(5), 10(6), 10(7)). An enthalpy porosity technique is used to trace the solid and liquid interface. Comparisons with previously published works show the accuracy of the obtained results. A maximum of 25.9% relative variation of freezing time with surface waviness was observed for lambda = 0.5, while the relative variation of freezing time with nanoparticles in comparison with surface waviness was negative for high values of lambda. It was observed that surface waviness can be used to control the solidification time based on enhancing different mechanism of solidification.