Blood based nanofluid flow driven by metachronal beating of artificial cilia

Cilia-driven transport is central to physiological pumping and emerging artificial cilia microfluidics, where metachronal waves can propel biofluids under low Reynolds number conditions. Motivated by magnetically controllable biomedical suspensions, this study investigates cilia induced pumping and heat transfer of a blood based Casson magneto nanofluid containing Fe₂O₃ nanoparticles through a symmetric channel. A key novelty is the inclusion of nanoparticle aggregation physics through aggregation-dependent viscosity and thermal conductivity closures (modified Krieger-Dougherty and Maxwell-Bruggeman models), enabling a direct comparison between aggregated and non-aggregated predictions under identical forcing. Using long-wavelength and creeping flow approximations, the governing equations are reduced to couple nonlinear ODEs, solved numerically in Mathematica (NDSolve). Results reveal that the blood velocity elevated toward the center of the channel with a strong reduction near the walls. The size of the trapped bolus becomes smaller with the increment of the Hartmann number. Importantly, accounting for aggregation substantially alters the pressure gradient relative to classical non-aggregation models, demonstrating that aggregation can meaningfully affect pumping power in cilia driven bio-nanofluid systems.