Numerical Investigation of the Effect of Storage Tank Orientation on the Melting of Phase Change Material in a Square-Shaped Tank

The storage capacity of surplus energy produced by renewable and conventional power plants makes latent heat storage units (LHSUs) using phase change materials (PCMs) relevant. The phase change processes are affected by the geometric shape of the PCM tank and the operating conditions to which it is subjected. This study explores the behavior of the melting process of paraffin (a PCM) in a square-shaped tank oriented in various orientations 0°, 30°, 60° and 90°. The results show that initially, the melting is dominated by thermal conduction, but as it progresses, natural convection takes over. Furthermore, the melting rate increases with the inclination angle. The total energy stored in a PCM during melting remains constant, although the time needed to store that energy can be considerably influenced by the orientation of the cavity.