Free Convective Flow of Non-Newtonian Nanofluids in Porous Media with Gyrotactic Microorganism

The two-dimensional steady laminar boundary-layer free convective flows along an isothermal solid horizontal flat plate located in a porous quiescent medium filled with non-Newtonian power law nanofluids that contain both nanoparticles and gyrotactic microorganisms are investigated numerically. The horizontal plate has uniform surface temperature, solute, nanoparticle concentrations and density of the motile microorganism. The governing partial differential equations are nondimensionalized, and then similarity transformations are developed using a linear group of transformations. Using similarity transformation, the governing equations are reduced to a system of nonlinear ordinary differential equations, which are solved numerically. The influence of controlling parameters on the dimensionless velocity, temperature, nanoparticle concentration, and density of motile microorganisms, as well as the local Nusselt, Sherwood, and motile microorganism numbers, are studied. It is found that the bioconvection parameters have strong effects on the flow, heat and mass transfer, and motile microorganism numbers. An excellent agreement is found between numerical results of the study with published results in the open literature for special cases.