Abstract
This article addresses the numerical approximation of third-grade nanoliquid flow over a stretchable rotating disk in the existence of nano-sized particles and gyrotactic motile microorgan-isms. The behavior of bioconvection is contemplated. The comportment of mixed convection, acti-vation energy and Joule heating effects are also considered. Further the nano-characteristics for Brownian dispersion of fluid particles and thermophoresis aspect are also taken into account. Utilizing appropriate scaling group of transformation variables, the partial differential equations are converted into governing ordinary differential system. Then coupled ordinary differential equa-tions are tackled numerically by using shooting technique via built-in function bvp4c solver with the help of computational software MATLAB. Graphical impact of miscellaneous arising sundry parameters on distribution, volumetric concentration of nano-particles, velocity field and rescaled density of motile micro-organisms are scrutinized and deliberated. The present model plays a crucial role in sectors of industry and engineering. This model is suitable for heating and cooling including engine cooling, microelectronics, biotechnology, bio-microsystems, cancer therapy, fertilizers and biofuel etc. Furthermore, the temperature distribution is enhanced for larger values of thermal radi-ation parameter. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University.