Cattaneo-Christov heat flux model in nanofluid flow on variable porous stretching sheet with effects of inter-particle spacing and nanoparticle’s radius using convective boundary conditions

The effects of inter-particle spacing and radius of molybdenum disulfide nanoparticle on nanofluid flow have significant applications in various fields. In biomedical engineering, optimizing these parameters enhance drug delivery systems, enabling more efficient targeting and controlled release of therapeutics. For such important applications, this work investigates nanofluid flow on a bi-directional elongating surface with effects of inclined magnetic field. The surface of sheet is characterized with variable porous features. This work specifically examines how the radii of nanoparticles and the spaces between them influence the overall dynamics of flow system. The Cattaneo-Christov heat flux model is also taken into consideration to investigate the heat flow. Main equations have converted to dimensionless form and then solved by implementing bvp4c approach. It has revealed in this work that with upsurge in magnetic factor, angle of inclination of magnetic field and variable porous factor there is reduction in primary and secondary velocities both for inter-particles spaces (say h = 1/2, & p 10) and radius of nanoparticles (say Rp = 3/2 & p 5/2). This reduction is more significant in case of large inter-particles spaces (say h = 10) and large radius of nanoparticles (say Rp = 5/2). With growth in radiation factor and thermal Biot number there is escalation in thermal distribution. When magnetic factor varies from 0.5 to 1.5 the skin friction C_fr alters from 2.1931 to 2.7233 in case of small inter-particle space (say h = 1/2) while C_fr varies from 2.2029 to 2.7355 in case of large inter-particle space (say h = 10) which shows maximum growth in C_fr for large inter-particle space (say h = 10). In contrast, maximum growth in C_gr has observed for small inter-particle space (say h = 1/2).