Performance evaluation of fin shape, quantity, and orientation for thermal storage enhancement in lithium nitrate trihydrate phase change material container

Among various PCM’s, the LiNO₃ 3 H₂O emerges as a promising candidate for thermal energy storage and transfer in low-temperature metal hydride hydrogen storage applications. PCM containers with three types of fin geometry such as rectangle, tapered and triangular fin are modelled. The rectangle and tapered fin had an improvement of 6.46% and 5.86% when compared with triangle fin. Three configurations of rectangular fins comprising one, two and three fins were developed and compared with no fin case. The case with one, two, and three fins had a 25%, 37% and 46% improvement over the case without fin. Fin tip clearance is analyzed for the natural convection with cases having 0.5 mm and 1 mm clearances exhibited similar melting rates. The fins were inclined at an angle to study its influence on melting. Inclining the fins at + 10° improved melting performance by 9% over the 0° case up to 85% liquid fraction. Conversely, a −10° inclination accelerated melting in later stages with an 8.6% overall improvement. This study offers insights into the melting behavior and convection current within the liquid PCM resulting from various fin position and structure, and their impact on energy storage performance.