Coupled influence of thermo diffusion and Brownian motion on bioconvection in Prandtl nanofluids across curved geometries

Abstract

This paper explores the innovative synergy between magnetohydrodynamics (MHD) and bioconvection in the flow dynamics of Prandtl nanofluids over curved surfaces. By introducing these coupled phenomena, the study uncovers a new realm of heat and mass transfer enhancement mechanisms that are uniquely applicable to advanced thermal systems. Curved interfaces play a pivotal role in the dynamics of nanofluid flow, particularly in systems where non-planar geometries are inherent, such as biological membranes, microchannel networks, or industrial heat exchangers. Partial differential equations numerically represent the study considering the curved surface's deformation vortices. The shooting method and the fourth-order Runge-Kutta approach are used to numerically solve the governing equations once they have been converted into ordinary differential equations via similarity transformations. MATLAB simulations are then utilized to evaluate the temperature, concentration, velocity, and bioconvective fields. The influence of MHD modifies fluid flow and heat distribution by the induced magnetic field, leading to alterations in the velocity profile and thermal boundary layer, ultimately enhancing heat dissipation efficiency. Simultaneously, bioconvection driven by buoyancy forces within the fluid medium creates intricate particle movements that redistribute the concentration of nanoparticles, directly influencing the system's thermal conductivity. Therefore, the study demonstrates that a synergistic increase in thermo diffusion and Brownian motion parameters leads to a peak enhancement of heat and mass transfer rates by up to 38 % and 42 %, respectively, compared to the flat plate scenario. In addition, higher Peclet numbers and microorganism density are found to amplify bioconvective cell accumulation near the surface, thickening the microorganism concentration layer.