Bioconvective Ferrohydrodynamic Flow in a Cylindrical Vessel Encircled by a Tumor

ABSTRACT This study investigates ferrofluid‐infused bioconvective flow within biological tissues, focusing on targeted heat‐ and mass‐transfer applications for tumor treatment under a uniform magnetic field. A horizontal cylindrical vessel, representing a blood segment surrounded by a tumor, is modeled to examine the transport of therapeutic nanoparticles and microorganisms. Unlike existing literature, this work specifically addresses the interaction between magnetic nanoparticles and motile microorganisms within a cylindrical geometry, assuming a homogeneous tumor with effective permeability. The governing nonlinear partial differential equations for flow and mass transfer are nondimensionalised via similarity transformations and solved numerically through the bvp4c function of MATLAB. The impact of parameters such as thermophoresis coefficient, Brownian motion coefficient, and concentration extravasion coefficients is investigated for temperature and concentration profiles. The results show that increasing interstitial fluid extravasation velocity and ferromagnetic interaction enhance near‐vessel heating, while the spatially averaged temperature decreases by approximately 6.3% and 3.6%, respectively, due to convective and magnetic redistribution of thermal energy. In contrast, nanoparticle and microorganism concentrations exhibit minimal variation in averaged magnitudes but undergo significant spatial redistribution across the domain. Additionally, bioconvective Peclet and Lewis numbers are shown to govern a critical balance between convective enhancement of fluid motion and diffusion‐limited microorganism transport. These findings highlight the importance of coupled ferrohydrodynamic–bioconvective effects in regulating thermal behavior and species transport, offering insights for optimizing magnetic hyperthermia and targeted nanoparticle‐based tumor therapies.