Regular Article

Enhancing flat plate collector efficiency with microtubes and sodium sulfate decahydrate-copper oxide PCM

School of Electrical and Electronic Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia

^* Corresponding author: najwan@usm.my

Received: 12 January 2024
Accepted: 29 October 2025

Abstract

Thermal energy storage not only conserves energy but also addresses the demand for renewable energy sources. Phase Change Materials (PCM) play a crucial role in storing solar thermal heat, thanks to their high heat of fusion and thermal conductivity. Incorporating PCMs has enhanced the performance of Flat Plate Collectors (FPCs). This particular design utilizes sodium sulfate decahydrate and copper oxide-based inorganic PCMs to effectively store thermal energy. The integration of this PCM with an FPC featuring microtubes has proven highly effective. The use of salt hydrate-based PCMs resulted in a notable 15% improvement in the efficiency of FPCs. Additionally, there is an enhancement in the storage time of thermal heat. To mitigate tube corrosion, copper oxide was introduced alongside sodium sulfate decahydrate. Simulation results were obtained across various Reynolds number values ranging from 1500 to 4000. Mathematical modeling and simulation were employed to assess thermal heat transfer, fluid dynamics, and heat loss. The simulation outcomes indicate a substantial improvement in the FPC’s efficiency, reaching up to 85%, attributed to the incorporation of PCM for heat storage.