Performance enhancement of photovoltaic panel by using microencapsulated phase change slurry in channel with staggered pins

Abstract

Microencapsulated phase change material (MPCM) in the form of particles suspended in conventional cooling fluids such as water has shown enhanced heat transfer characteristics when compared to conventional single phase heat transfer fluids. This is attributed to the latent heat of fusion of the MPCM, which results in higher heat capacity of the heat transfer fluid. The thermal performance of MPCM slurry as a heat transfer fluid can be further improved when used in a channel consisting of staggered pins. Use of MPCM slurry in heat transfer channels can result in efficient cooling performance of photovoltaic (PV) systems, where significant thermal loads are prevalent due to high levels of irradiance or working in hot climate conditions. The present work investigates numerically the impact of using MPCM slurry at different mass fractions on the cooling performance of a heat transfer channel attached to a PV panel. The numerical simulations were performed using the ANSYS-FLUENT solver in combination with user-defined functions used to account for the thermophysical properties of MPCM slurry. It was observed that the Nusselt number of MPCM slurry was much higher than for water as single-phase fluid, especially at higher mass fractions at the same flow rate. Moreover, the PV panel temperature was found to be significantly reduced when phase change material in the MPCM slurry experienced melting. Moreover, using staggered circular pins in the channel resulted in a significant reduction of the PV panel temperature even under concentrated irradiance conditions. However, an increase in pumping power was noticeable at high mass fraction of MPCM slurry. Finally, a remarkable increase in the PV panel efficiency was achieved under normal and concentrated irradiance levels by using MPCM slurry in the cooling channel with and without staggered circular pins.