Melting-driven MHD mixed convection heat transfer in a ternary hybrid nanofluid over an inclined surface

Despite extensive research on nanofluids and magnetohydrodynamic (MHD) flows, the simultaneous investigation of melting heat transfer, thermal radiation, and ternary hybrid nanofluid (THNF) on inclined surfaces remains unexplored, presenting a significant gap in thermal management literature. This work addresses this gap by examining the combined effects of melting phenomena, MHD, and mixed convection in a THNF composed of copper (Cu), aluminum oxide ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Al</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">O</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>3</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> ), and titanium dioxide (TiO 2 ) nanoparticles flowing over an inclined surface. Similarity transformations and numerical solution via the Keller box method are employed to solve the governing equations, incorporating mixed convection and thermal radiation effects. Key results demonstrate a substantial enhancement in the local Nusselt number of THNF by ∼19% due to the melting phenomenon, accompanied by a 6% increase in the skin friction coefficient. The skin friction coefficient increases on the stretching sheet but decreases on the shrinking sheet. Furthermore, the melting parameter leads to a significant decrease in temperature profiles (around 18%), whereas the inclination parameter causes a minor increase (∼3%) for both stretching and shrinking scenarios. Notably, the analysis confirms that THNF demonstrates superior thermal performance compared to conventional hybrid and single-component nanofluids. These results provide actionable insights for designing nanoengineered thermal management systems applicable to solar thermal collectors, battery cooling systems, and advanced heat exchangers, directly supporting the development of efficient and sustainable energy technologies.