Abstract
The present paper concerns the bioconvective flow, mass and heat transfer including motile microorganisms on a vertical surface saturated with porous materials of variable porosity. Because of variable porosity, other fluid properties are assumed to be porosity-dependent. The physical laws that govern the fluid flow and microorganism concentration are modeled into a set of coupled partial differential equations and simplified into corresponding nonlinear ordinary differential equations with similarity variables. Numerical solutions are obtained using in-built functions in Maple 14.0 to ease the hardship connected with computational complexity in the nonlinear problem. Graphical solutions of the symbolic results are presented and fully explained in accordance with the physics of the fluid for the velocity, temperature, concentration and motile microorganism density profiles for uniform and variable permeability and also in porous, non-porous cases. Mixed convective parameter
λ
has pronounced effect on heat mass and motile microorganism transfer rate in case variable permeability with porous surface.