Numerical treatment of melting characteristics of angular oriented flat tube in a double tube latent heat energy storage unit

The latent heat energy utilized phase-change material stores enormous amounts of energy in relatively small spaces. The poor thermal conductivity of the phase change material has a significant drawback. Several techniques have been developed to solve this drawback, a geometrical modification was applied to predict the impact on the charging rate and time of the phase change material. A numerical analysis is presented to optimize the angular orientation of the inner flat tube in a double tube latent heat storage system. ANSYS 17.2 was used to execute a two-dimensional unsteady numerical model. The numerical model was validated via experimental published work. Twenty numerical cases of inner flat-tube aspect ratios of 0.5, 0.6, 0.7, 0.8, and 0.9 with angular orientations of 0 degrees, 30 degrees, 60 degrees, and 90 degrees were analyzed. The findings showed that; as the aspect ratio decreases, the average charging rate improvement is increased. For aspect ratios of 0.9 and 0.5, the improvement in entire charging time for the greatest orientation (theta = 90 degrees) relative to the horizontal flat-tube case (theta = 0 degrees) was 11.19% and 49.46%, respectively. The inner tube with an aspect ratio of 0.5 and angular orientation of 90 degrees had the highest average charging rate.