Elfeky K.E., Mohammed A.G., Wang Q., Ge K., 2025, Assessment of the Thermocline Thermal Energy Storage Tank Thermal Expansion, Chemical Engineering Transactions, 120, 211-216.
A packed-bed thermocline tank offers a cost-effective solution for thermal energy storage in concentrating solar power (CSP) plants. However, structural issues caused by thermal expansion have limited its deployment. This study develops a comprehensive model of a multilayer thermocline tank incorporating a composite steel shell with dual-layer insulation and encapsulated phase change materials (PCMs) suspended in molten salt. The model independently accounts for the varying thermal properties of molten salt and PCMs to evaluate the thermo-mechanical performance of the tank. Results show that the section of the tank wall exposed to high temperature expands by 30.5 % as charging time increases from 50 to 300 min. Additionally, the equivalent stress distribution exhibits multiple peaks due to thermocline movement, reaching 184.7 MPa at 208 min. The study demonstrates the importance of thermal expansion analysis for improving structural integrity and optimizing tank design in high-temperature CSP systems.
