Irreversibility estimation in triply stratified bio-marangoni convection in powell-eyring nanofluid under the influence of external flow

Abstract

Due to the growing importance of bioconvection phenomena in diverse industrial processes such as oil refining, biotechnology, and food processing, it is essential to examine several effects like a chemical reaction, stratification, Marangoni convection, etc. in nanofluid suspensions in the context of transport of microorganisms. The outcome of such studies may provide significant insight into controlling and as well as manipulating the transport of energy, solute, and microorganisms for achieving the requisite target. The aim of} our study is to investigate the thermo-solutal Marangoni convection of gyrotactic microorganisms suspended in Powell-Eyring nanofluid in a stratified medium. This analysis also takes into account the effects of external flow and transverse magnetic
 field. The impact of Arrhenius activation energy, thermal radiation, and binary chemical reactions on bioconvection
 flow is considered under stratified Marangoni convection. Under appropriate assumptions without violating the physics, the present problem is expressed in terms of nonlinear PDEs. Some capable similarity transformations are employed to convert the PDEs into ODEs and solved numerically by the Runge-Kutta Fehlberg method. The graphical
 illustrations depict the effects of relevant flow parameters on temperature, nanoparticle volume fraction, and
 density distributions of motile microorganisms. The study focuses on understanding the variations in significant engineering quantities resulting from changes in crucial effects and analyzing irreversibilities. It is noticed
 that Marangoni accelerates the mass transfer process while on the other hand delaying the heat transfer
 and microorganism’s density gradient. The dominance of Powell-Eyring nanofluid on the heat and mass
 transport amplified in accompanying Marangoni convection. The results indicate that the Eyring-Powell fluid significantly reduces entropy generation and the Bejan number. Conversely, an increase in entropy generation is observed for the Marangoni ratio parameter. Hence, this work provides insight into interlinked flow in bioconvective systems, with potential diverse applications in microbiological processes.