Experimental investigation of thermal performance of NanoEncapsulated-PCM emulsions in parallel plate thermal energy storage system

Abstract

This study investigates the thermal performance of nanoPCM emulsions (nanoPCMEs) as working fluids in parallel plate thermal energy storage system, comparing two configurations: solid aluminum walls and aluminum profile walls filled with PCM + metal foam. Three distinct nanoPCM emulsions were evaluated against pure water as a base fluid. The experimental results demonstrated superior convection heat transfer performance for all nanoPCMEs compared to pure water. In the solid aluminum wall configuration, maximum thermal energy storage reached approximately 900 kJ, with 2.0 wt% nanoPCME achieving this level twice as fast as pure water. The PCM + metal foam configuration exhibited enhanced performance, storing up to 2250 kJ of thermal energy due to PCM's high latent heat, reaching maximum storage 1.6 times faster than pure water. Notable improvements in heat transfer were observed, with nanoPCME achieving the highest average Nusselt numbers across all configurations. Maximum enhancements in Nusselt number were 34.5 % and 41.9 % for solid wall and PCM + metal foam configurations, respectively, using 2.0 wt% nanoPCME. These findings demonstrate the significant potential of nanoPCMEs for improving thermal energy storage systems and thermal control applications.