TY - JOUR TI - Numerical investigation on solidification behavior of paraffin in a vertical finned latent heat energy storage unit AU - Su Qingzong AU - Zhang Fan AU - Li Ke AU - Yu Gewen AU - Gu Xiaodi AU - Liu Yang AU - Wang Yaxiong AU - Duan Jianguo AU - Ma Qing JN - Thermal Science PY - 2026 VL - 30 IS - 3 SP - 2265 EP - 2281 PT - Article AB - To enhance the heat exchange efficiency of the latent heat energy storage unit, it is necessary to solve the problems of long solidification time and poor uniformity of PCM, thereby shortening the complete cycle time. A 3-D simulation model was established to explore the strengthening mechanism of different fin structural parameters and arrangements on the solidification behavior, and an experimental setup was built to verify the simulation model. The results showed that the evenly arranged vertical fins can significantly shorten the complete solidification time. Compared with increasing the thickness, increasing the height of the fins is more conducive to accelerating the solidification. Moreover, when the PCM-fin height is 30.0 mm and the thickness is 2.0 mm, the solidification time is shortened by 42.82% compared with the unit without fins. In addition, the air fins have a more obvious strengthening effect on natural convection in the initial stage of the solidification process, while the fins on the PCM side have a more significant heat conduction effect in the later stage. The addition of bilateral fins reduced the solidification time by 48.15% and the total time required to complete the solid-liquid cycle of PCM by 56.94%. The proposed bilateral fins method optimizes heat exchange efficiency in latent heat energy storage units by enhancing both natural convection and conduction, making it suitable for solar thermal and low temperature waste heat recovery applications. DO - 10.2298/TSCI250801232S ER -