Experimental Study of Branching Fins for Enhanced Heat Transfer in Latent Energy Storage System

Abstract

Thermal energy from sustainable sources is a growing percentage of the global energy budget, one which requires storage technologies for effective use. For thermal energy, latent heat energy storage systems (LHESSs) offer the potential for significantly improved energy density and quality compared to traditional systems. Most materials suitable for use in LHESSs, however, have very low thermal conductivities leading to limited heat transfer rates and requiring advances in heat exchanger design for these systems.

A comparative study was performed between a heat exchanger with bifurcated fins and heat exchangers with straight fins within a LHESS. The bifurcated fins transferred less energy than the straight fins during charging tests due to their reduced ability to form convective cells of molten phase change material. During discharge the bifurcated geometry provided a lower but steadier rate of heat transfer, and exchanging slightly more energy over an eight-hour period than the straight fins.