Optimizing the thermal performance in parabolic solar trough collectors: investigating the impact of ionic nanofluid and revolving fins inserts

In the present study, simulations are conducted to investigate the influence of aluminum oxide (Al₂O₃) nanoparticles in [EMIM][BF₄] ionic fluid with different-shaped spinning fins in the receiver tube of parabolic solar trough collector (PTC). Utilization of ionic fluids is emerging as a novel approach in engineering, particularly in heat transfer applications. However, their integration with nanofluids and specific geometries such as spinning fins in solar collectors remains relatively unexplored. Nanoparticles are being considered at 1% volume content within an ionic-based liquid. The flow rate of the working liquid ranges between 0.033 kg/s and 0.016 kg/s. The entire simulation for tested models is conducted using ANSYS Fluent. Additionally, Tonatiuh is utilized for optical simulation. The spinning speeds of the set of fins range between zero radians per second speed to fifteen radians per second. The results indicate a highest thermal efficiency increment of 27.21% for Case-3 at a fin revolving speed of fifteen radians per second, compared to a steady single receiver tube using ionic nanofluid at 0.033 kg/s. Under similar operating conditions, the pump work requirement increases by 13.43% for Case-3 compared to a steady single receiver tube. Thus, the present investigation offers an original perspective for determining the appropriate modified PTC model in terms of thermal performance and pump work demand.