Entropy optimization in bio-convective chemically reactive flow of micropolar nanomaterial with activation energy and gyrotactic microorganisms

Abstract

The main objective of this research paper is to scrutinize the entropy generation(EG) in the bioconvective flow of micropolar fluid by porous surface of a stretched sheet. Mixed convection effects are considered. Thermal radiation, internal fluid friction, Joule heating, and heat generation aspects are accounted for in the energy relation. Mass concentration relation is developed because of the binary chemical reactions associated with Arrhenius kinetics. The governing equations for the micropolar fluid are developed based on Buongiorno's model with the help of boundary layer restrictions. By invoking the transformation procedure, dimensional model is made dimensionless. The well-known shooting technique RKF-45 in Mathematica software is implemented to solve the transformed equations. Performance of micropolar fluid velocities, thermal field, entropy generation, mass concentration, Bejan number, and motile density versus influential variables are highlighted. Furthermore, the intensity of skin friction, Nusselt quantity, motile density, and Sherwood number is computed and analyzed. It is observed that the rate of EG improves while the Bejan number diminishes versus higher Brinkman number, and diffusion parameter due to gyrotactic microorganisms. Magnitude of heat transfer rate boosts through higher Γ, Qs, Ec, Ha and Rd at an average percentage of 44, 82, 189, 156 respectively.

Keywords

• Entropy generation
• Micropolar fluid
• Bioconvection
• Activation energy
• Mixed convection