Structural Optimization of Internal Heat Sources and its effect on the Melting Behavior of Solid PCM in a Single Tank

Molten salt energy storage is an effective technology for integrating renewable energy and supporting zero-carbon building goals. To ensure the safety and reliability of storage tanks, this study conducts a numerical analysis of the melting process of solidified molten salt in a single-tank system under extreme conditions. A new high-temperature molten salt single-tank model is developed, using Hitec molten salt as the medium. The study examines the effects of heater position and heating power on the melting behavior. The findings show that: (1) Increasing the number of heaters has a limited impact on the overall melting rate but improves heat distribution and optimizes the unmelted areas. (2) Placing heaters closer to the tank’s bottom increases both the melting rate and uniformity, with natural convection playing a key role in heat transfer. (3) Increasing heating power shortens melting time, but the effect diminishes over time. Natural convection initially strengthens but weakens as melting progresses. This study offers key insights for the design and operation of molten salt energy storage systems and supports the development of single-tank configurations. Additionally, this technology is essential for balancing renewable energy sources in zero-carbon buildings, aiding their sustainability goals.