An Evaluation Of The Stability Of Zno And Al2O3 Nanoparticles In Nanofluids For Heat Transfer Applications In Radiators

Abstract

Nanofluids, which are suspensions of nanoparticles in a base fluid, have shown promising potential for enhanced thermal conductivity and heat transfer in various applications. Among these, Al₂O₃ (aluminum oxide) and ZnO (zinc oxide) nanofluids are widely studied due to their favorable properties. This study focuses on the stability analysis of Al₂O₃ and ZnO nanofluids prepared with water as the base fluid. Stability is a critical parameter for the effective utilization of nanofluids, as it directly affects their thermophysical properties and practical applications. To assess stability, various techniques such as UV-Vis spectroscopy, zeta potential measurements, and sedimentation analysis were employed. The effects of nanoparticle concentration, pH, surfactant addition, and ultrasonic agitation on the stability of these nanofluids were systematically investigated. The zeta potential analysis indicated that both Al₂O₃ and ZnO nanofluids exhibit enhanced stability at optimal pH levels and with appropriate surfactant concentrations, ensuring electrostatic repulsion between particles. Moreover, the stability of nanofluids was found to be time-dependent, with ZnO nanofluids showing slightly better stability over extended periods compared to Al₂O₃. The findings highlight the importance of optimizing the preparation conditions to achieve stable nanofluids, which is crucial for their practical application in heat transfer systems. This study provides valuable insights into the formulation of stable nanofluids, paving the way for their effective use in industrial and engineering applications. In this research work the nanofluid stability for Al₂O₃ and ZnO nanofluid for various Volume concentration is tested. From study it has been observed that the Al₂O₃ nanofluid is more stable than the Zno nanofluid.