Thermo-bioconvection in horizontal wavy-walled porous annulus

The present investigation centers around a numerical study of the impact of the presence of phototactic microorganisms on the thermo-bioconvection inside a wavy-walled horizontal porous annulus that is saturated with a Newtonian fluid. Consequently, an equation describing the movement of the microorganism cells is added to the mathematical model of natural convection. The thermal equilibrium, Oberbeck-Boussinesq approximations and Darcy law are taken into consideration. The transformed dimensionless partial differential equations with the temperature-concentration-stream function formulation are discretized applying the alternate direction implicit finite difference scheme. Results confirm that in the absence of microorganisms the Nusselt number decreases with the increase of the amplitude of wall waviness. It was also observed that the wall waviness influence the thermo-bioconvective instabilities and the flow regime structure. (C) 2021 Elsevier Masson SAS. All rights reserved.

Automated summary

This study numerically investigates the impact of phototactic microorganisms on thermo-bioconvection in a wavy-walled horizontal porous annulus saturated with a Newtonian fluid. The results show that an increase in the amplitude of wall waviness leads to a decrease in the Nusselt number, and influences thermo-bioconvective instabilities as well as flow regime structure.