Abstract
.The transient process in a finned triplex tube during solidification of NEPCM was reported numerically. We tried to increase conduction by adding aluminum oxide (Al2O3) nanoparticles and metallic fins. To simulate the transient problem with an adaptive grid, the best choice is the Galerkin finite element technique that we have considered in the current research. Contours illustrate that adding alumina makes the conduction stronger and choosing dp=40 nm results in the best discharging rate. Utilizing a longer fin tends to expedite discharging due to augmentation in thermal diffusion.