BIOCONVECTIVE HEAT TRANSPORT IN WALTER'S-B NANOFLUID EMBEDDED WITH GYROTACTIC MICROORGANISMS

Abstract

The study of nanofluids has gained considerable attention due to their enhanced thermal conductivity and superior heat transfer characteristics compared to conventional fluids. Nanofluids are engineered by dispersing nanoparticles within a base fluid, thereby improving thermal transport performance in various engineering and biomedical applications. Recent developments in non-Newtonian fluid mechanics have further expanded research into complex fluid models such as Walter's-B viscoelastic fluids, which exhibit both viscous and elastic behavior. Simultaneously, the incorporation of gyrotactic microorganisms into nanofluids has introduced the phenomenon of bioconvection, where the collective motion of microorganisms influences fluid stability, heat transfer, and mass transport. Bioconvection generated by motile microorganisms plays an important role in enhancing suspension stability and preventing nanoparticle sedimentation. These characteristics make bioconvective nanofluids highly relevant in applications involving biofuel production, biomedical engineering, microbial systems, and advanced thermal management technologies. This research investigates bioconvective heat transport in Walter's-B nanofluid embedded with gyrotactic microorganisms. The physical model considers steady two-dimensional flow with Brownian motion, thermophoresis effects, nanoparticle concentration transport, and microorganism conservation mechanisms. The governing nonlinear partial differential equations representing momentum, energy, nanoparticle concentration, and microorganism density are transformed into ordinary differential equations using similarity transformations. Numerical methods are employed to obtain solutions and analyze the influence of various dimensionless parameters on fluid flow and thermal transport characteristics. Particular emphasis is placed on examining the effects of the Walter's-B parameter, Brownian motion parameter, thermophoresis parameter, bioconvection Lewis number, Peclet number, and microorganism concentration parameter. The study evaluates velocity distribution, temperature profiles, nanoparticle concentration fields, and microorganism density distributions. Existing investigations have shown that Brownian motion and thermophoresis significantly influence heat transfer rates, while gyrotactic microorganisms affect bioconvective stability and transport phenomena. The findings are expected to contribute to the understanding of coupled thermal, biological, and fluid dynamic processes occurring within non-Newtonian nanofluids. The study provides insights into advanced heat transfer mechanisms and offers potential applications in biotechnology, bioengineering, cooling technologies, microfluidic devices, and energy systems. The integration of gyrotactic microorganisms with Walter's-B nanofluids represents a promising approach for enhancing heat transport performance and improving suspension stability in complex thermal systems.