Impact of magnetic field strength and inclination on mini-channel cooling performance in photovoltaic panels using CuO-based nanofluids

Abstract

The present study investigates the thermal performance enhancement of a photovoltaic (PV) solar panel cooling system by strategically utilizing a 2% CuO–water nanofluid. The nanofluid is circulated through a planar channel, below the PV panel, with dimensions of 40 mm in length and 4 mm in width over fluid Reynolds numbers (Re) from 100 to 250. Active vortex generators, represented by strategically positioned magnets with varying magnetic strengths from 1000 to 2000 G, are incorporated at distinct intervals along the channel length. Understanding how a magnetic field and the orientation angle from 0° to 45° of the channel affect the thermal performance of the PV panel cooling system is the primary objective of this study. The analysis is carried out utilizing the finite volume method-based solver. Four key performance parameters—the Nusselt number (Nu), skin friction coefficient (f), Colburn j-factor (j), and thermal enhancement factor (TEF)—are carefully studied to assess the increase in thermal efficiency of the panel. Results show that increasing the magnetic field strength from 0 to 2000 G enhances the Nusselt number by up to 39.37%, the Colburn j-factor by 24.85%, and the TEF by 13%. Adjusting the channel inclination to 45° further improves Nu and TEF by 21.9% and 15.05%, respectively. Repositioning magnets from 7.5 to 32.5 mm downstream yields an additional 11.7% and 13.06% increase in Nu and TEF, respectively. While these enhancements come with a friction factor rise of up to 46.6%, they highlight the importance of optimized configurations. The outcomes of this study are notably promising, with the TEF consistently surpassing unity. These results underscore a substantial improvement in the cooling efficiency of solar panels when integrated with such active vortex generators, thereby enhancing the overall power generation potential of the system. The findings of this study support the idea that carefully tuned combinations of magnetic fields and nanofluids can be leveraged in modern PV cooling systems, with potential applications in microfluidics, electronics cooling, and other areas demanding compact and efficient heat dissipation strategies.