Entropy generation in peristaltic transport of a bioconvective nanofluid flow with gyrotactic microorganisms in an inclined channel: Rabinowitsch fluid model

This study investigates entropy generation in peristaltic motion involving microorganisms within a Rabinowitsch nanofluid (RNF) flow through an inclined channel. The analysis addresses complex, nonlinear coupled partial differential equations using a semi-numerical homotopy perturbation method. The study employs long wavelength (ζ << 1) and small Reynolds number ( Re → 0) approximations to simplify the system. A comprehensive assessment explores the effects of critical physical parameters on velocity, temperature, concentration, microorganism conservation, and entropy generation, with findings illustrated through detailed graphical representations. The study further investigates the skin-friction coefficients, presenting significant variations in entropy generation and Bejan number under different physical parameter configurations. The primary objective is to reduce entropy generation to improve overall efficiency. Results indicate that entropy generation in the peristaltic transport of microorganisms within an RNF can be minimized effectively by tuning specific parameters. Hence, it is found that the entropy generation rate increases with the enhancement of the values of the Grashof number, Brinkman number, radiation parameter and body force parameter. The Bejan number increases at both walls with rising values of the buoyancy ratio and the angle of inclination. Also, the entropy generation and Bejan number are elevated near the walls, while it reduces in the central region of the channel. The novelty of this work lies in its analysis of microorganism dynamics, such as microbes or bacteria, in relation to velocity, heat, and nanoparticle distributions in a non-Newtonian Rabinowitsch fluid system. It provides a comprehensive understanding of microorganism interactions in complex fluid flows. The microorganism profile decreases as the bio-convection constant, chemical reaction parameter, Peclet number, and Schmidt number are enhanced. Further, increasing the body force parameter F from 1.0 to 1.5 decreases the skin friction rate by 20.42%, while further growing F from 1.5 to 2.0 yields a 12.82% reduction. Similarly, raising the buoyancy ratio parameter Nr from 1.0 to 5.0 increases the skin friction coefficient by 56.95%, with an additional 45.35% increase when Nr is raised from 5.0 to 10.0.