Application of actively enhanced solar phase change heat storage system in building heating: A numerical and statistical optimization study

Phase change heat storage technology plays a crucial role in enhancing the utilization of solar energy for building heating applications. Nonetheless, the low thermal conductivity of phase change material hinders its widespread implementation. This study presents a novel approach by implementing a phase change heat storage system under rotation conditions to improve heat transfer efficiency. Specifically, the impact of different degrees of rotation center shift on the heat storage process is investigated using a validated numerical model. The research examines the thermal performance of the system under varying rotation center distances (0–300 mm) and speeds (0.1–0.3 rpm) through comprehensive analysis based on statistical and Taguchi methodologies. The findings indicate that adjusting the rotation center shift and increasing the rotation speed enhance forced convection within the unit, thereby accelerating the melting process. For instance, at a rotation speed of 0.2 rpm, the melting time can be reduced by 34.76 % and 5.66 %, while the average heat storage rate can increase by 51.53 % and 5.72 % when the rotation center distance is extended by 300 mm and the rotation speed is increased by 0.2 rpm. Moreover, the Taguchi design analysis reveals that the rotation speed significantly influences the melting time and average heat storage rate, with contributions of 56.68 % and 54.22 % respectively, surpassing the impact of rotation eccentricity.