Free convection investigation for a Casson-based - nanofluid in semi parabolic enclosure with corrugated cylinder.

The optimization of heat transfer in various engineering applications, such as thermal management systems and energy storage devices, remains a crucial challenge. This study aims to investigate the potential of Casson-based Cu-HO nanofluids in enhancing free convection heat transfer within complex geometries. The research examines the free convection heat transfer and fluid flow characteristics of a Casson-based Cu-HO nanofluid within a semi-parabolic enclosure that includes a wavy corrugated cylinder. Utilizing numerical simulations based on the Galerkin Finite Element Method, the study investigates the impact of different factors, including the Rayleigh number (10 ≤ Ra ≤ 10), Casson fluid parameter (0.1 ≤ γ ≤ 1), corrugation number (3 ≤ N ≤ 10), nanoparticle volume fraction (0 ≤  ≤ 0.15), and enclosure inclination angle (0° ≤ ζ ≤ 60°), on both heat transfer efficiency and flow patterns. The results reveal that increasing the Rayleigh number and Casson fluid parameter enhances heat transfer performance, with the average Nusselt number increasing by up to 165 % as Ra increases from 10 to 10. An optimal range of corrugation numbers is identified for maximizing heat transfer at higher Rayleigh numbers. The addition of nanoparticles significantly improves heat transfer, with a 20 % increase in the average Nusselt number observed at Ra = 10 when the nanoparticle volume fraction increases from 0 to 0.15. These findings provide valuable insights for designing more efficient thermal management systems in applications such as electronics cooling, solar thermal collectors, and heat exchangers, potentially leading to improved energy efficiency and performance in various industrial and technological sectors.