Transient Thermal Performance Analysis of Nanoparticle-Coated Flat Plate Solar Collectors Using MATLAB-Based Modeling

Abstract

Flat plate solar collectors (FPCs) have significant thermal performance that is vital in improving the efficiency of solar thermal energy systems. Traditional absorber coating, including black paint, has limited optical and thermal behavior, and nanomaterial-based absorber coating has received interest in improving performance. The purpose of the study is to assess and compare the thermal performance of FPCs when coated with CuO, Al2O3 and graphene nanoparticles. A mathematical model simulator of the performance of the collector under dynamic solar and environmental conditions was created using transient lumped capacitance in MATLAB. The model computes the important thermal performance indicators, such as outlet fluid temperature, useful heat gain, and instantaneous efficiency, and it has been verified against literature data. Simulation findings indicate that nanomaterial coatings are much more efficient in terms of thermal conductivity with graphene showing the most dramatic efficiency improvement of up to 0.835 relative to 0.725 when using black paint and a maximum useful heat gain of 834 W relative to 724 W. Graphene-coated collectors on average increased efficiency by 15.2% and useful heat gain by 13.8%. The improvements of Al2O3 and CuO coating were around 9-11% higher than black paint. Such improvements are explained by the high thermal conductivity and optical absorption of nanoparticles. The results show the promise of advanced nanocoatings to enhance the efficiency of solar thermal systems and offer a solid basis to optimize and experimentally validate such systems in the future.