Experimental and numerical analysis of hybrid nano-enhanced phase change material (PCM) based flat plate solar collector

The present investigation examines a flat-plate solar collector (FPC) with a water heater that employs paraffin wax as a durable Phase change material (PCM) for solar energy storage. Paraffin wax, typically having low conductivity, can be improved by adding highly conductive hybrid nanoparticles. Combining MWCNT (excellent thermal conductivity) and SiO2 (influence of shape and phase transition characteristics) nanomaterials reinforced with Paraffin wax (PFW) of 1.0 wt% to improve thermal conductivity and then incorporated in FPC results in hybrid nano-enhanced PCM (HnPCM). From 8:00 a.m. to 8:00 p.m., the aforementioned experiment uses a 100-l water tank for water heating and analyzes the effect on the output temperature of FPC incorporating HnPCM. As a result of experimentation, FPC demonstrated superior performance with and without HnPCM, achieving efficiencies of 64.7 % and 71.7 %, respectively. Furthermore, it sustained hot water production for an extended period, even throughout the evening, with a maximum outlet temperature of 70 degrees C with HnPCM. Following a similar approach, numerical analysis is carried out in Computational Fluid Dynamics (CFD) software. A threedimensional transient CFD model was developed predicts the operational performance of the system with reasonable accuracy. ANSYS FLUENT simulates and analyzes the FPC to validate collector flow properties, notably temperature and pressure patterns. The results are compared to existing experimental data with a maximum relative error of 2.56 % and 3.44 %, respectively. This work outlines the impacts of the main operational conditions to the tile-shaped dual-function solar collector's efficiency. From a summary of the computational and experimental studies, it is evident that using HnPCM in the FSC greatly enhanced the acquired heat and can be incorporated for different solar energy storage applications.