MHD Radiative Natural Convective Heat Transfer Enhancement for Casson Nanofluid Flow on a Horizontal Circular Cylinder.

The current numerical analysis investigates the sensitivity of heat transfer enhancement in the magnetohydrodynamic radiative natural convection flow of a Casson nanofluid over a cylinder, which has significant ramifications for different fields of science, e.g., biomedical devices, aerospace engineering, nanofluid-based cooling systems, energy harvesting devices, and drag reduction in marine engineering. The effects of numerous physical parameters on heat transfer characteristics are investigated using numerical and statistical simulations. Here methanol is taken as the base Casson fluid, while enhancement is achieved by introducing the nanoparticles such as graphite oxide, along with single-wall carbon nanotubes and multi-walled carbon nanotubes. The transformed governing differential equations are numerically solved using a second-order accurate implicit finite difference scheme known as the Keller-Box technique. To conduct the sensitivity analysis RSM is used to explore the impact of various physical quantities on heat transfer. The influence of Nusselt number (Gr−1/5Nu) and skin friction (Gr1/5Cf) against various physical quantities associated with the behaviour of Casson nanofluid flow are shown in terms of graphs and tables. One of the key findings is that an increase in the Casson parameter leads to a reduction in Gr1/5Cf and an increase in theGr−1/5Nu. Moreover, among the nanoparticles studied, multi-walled carbon nanotubes prove to be the most effective in enhancing heat transfer.