Darcy–Forchheimer MHD rotationally symmetric micropolar hybrid-nanofluid flow with melting heat transfer over a radially stretchable porous rotating disk.

This study fills a gap in the literature by exploring the complex interplay between microrotation, magnetic fields, and temperature factors in hybrid nanofluids, improving our understanding of their behavior and potential usage. For hybrid nanofluids, this study examines their combined effect rather than individual components. The hybrid nanofluids, specially engineered mixture of base fluid, which is water, and two types of nanoparticles, titanium dioxide (TiO2) and iron oxide (Fe3O4), known for their remarkable energy transfer capabilities, are investigated. These fluids find applications in heat generation, micropower generation, and solar collectors. The research focuses on understanding the impact of various factors, including microrotation, inertial characteristics, thermal radiation, melting heat transfer, and Joule dissipation, on surface heating in the presence of a radially stretchable rotating disk. The governing equations are transformed into ordinary differential equations using similarity variables, and the study employs the homotopy analysis method for a semi-analytical solution. The results reveal how temperature, velocities, heat transmission rates, and skin-friction change under different material properties. This research has implications for magnetohydrodynamics in space propulsion, radiative heat transfer in high-temperature applications, and solar thermal systems. It also contributes to environmental engineering and automotive cooling systems. [ABSTRACT FROM AUTHOR]