In this work, the melting process of compounds containing nanoparticles of NePCM in a square hole with different angles affected by two pairs of well-spring heat source on horizontal walls was numerically investigated. Four different configurations of elements were employed to investigate the effect of changes in the position of elements on the horizontal walls of the well-spring landscape on the ratio of liquid fraction. In the first case, the springs and wells have been located on horizontal walls separately. The environmental condition in the second case is that the spring-well elements have been set on the horizontal walls alternatively. In the third case, springs are on the left of well elements, and ultimately in the fourth case, spring and well elements are all set at the bottom of horizontal walls. Results show that in the first arrangement, using 2%weight of Al2O3 nanoparticles, compared to other cases, the highest ratio of liquid fraction is obtained. پرونده مقاله