Comparison of circular- and cross-oriented phase-changing material spherical balls for charging and discharging cycles

Abstract

The current work investigates the performance of charging and discharging cycles of phase-changing material encapsulated inside spherical balls required for latent heat thermal energy storage of water. The objective is to compare the newly formed circular- and cross-orientations for their feasibility in domestic applications. A water heater of 230 V, 2000 watts of power is passed down to charge n-tetracosane (selected PCM), thereby liquefying it proficiently from an ambient temperature to 85°C. For the discharging process, solidification of PCM is monitored against the time required to return the PCM inside spherical balls to its original solid state. The time taken for charging is 4.5 h for circular-orientation and 3.16 h for cross-orientation. While for discharging, the time take is 20 h for circular-orientation and 19.5 h for cross-orientation. N-tetracosane, hence, is suitable to store water up to 20 h when worked in circular-orientation, depicting best results. These cycles for both orientations are validated with the CFD analysis using ANSYS Fluent, and a rational concurrence is accomplished. Also, the reason for digression is clear.