TY - JOUR
TI - Melting of a phase change material in a horizontal annulus with discrete heat sources
AU - Mirzaei Hooshyar
AU - Dadvand Abdolrahman
AU - Mastiani Mohammad
AU - Sebti Seyed Sahand
AU - Kashani Sina
JN - Thermal Science
PY - 2015
VL - 19
IS - 5
SP - 1733
EP - 1745
PT - Article
AB - Phase change materials have found many industrial applications such as  cooling of electronic devices and thermal energy storage. This paper  investigates numerically the melting process of a phase change material in a  two-dimensional horizontal annulus with different arrangements of two  discrete heat sources. The sources are positioned on the inner cylinder of  the annulus and assumed as constant-temperature boundary conditions. The  remaining portion of the inner cylinder wall as well as the outer cylinder  wall is considered to be insulated. The emphasis is mainly on the effects of  the arrangement of the heat source pair on the fluid flow and heat transfer  features. The governing equations are solved on a non-uniform O type mesh  using a pressure-based finite volume method with an enthalpy porosity  technique to trace the solid and liquid interface. The results are obtained  at Ra=104 and presented in terms of streamlines, isotherms, melting phase  front, liquid fraction and dimensionless heat flux. It is observed that,  depending on the arrangement of heat sources, the liquid fraction increases  both linearly and non-linearly with time but will slow down at the end of the  melting process. It can also be concluded that proper arrangement of discrete  heat sources has the great potential in improving the energy storage system.  For instance, the arrangement C3 where the heat sources are located on the  bottom part of the inner cylinder wall can expedite the melting process as  compared to the other arrangements.