Effects of throughflow and internal heating in a composite air-porous medium

The effect of an internal heat source linearly dependent on the solid fraction on the onset of convection in a composite air-porous channel with vertical throughflow has been analyzed. We considered boundaries to be insulating to temperature perturbations. The governing equation that satisfies the air-porous configuration is analyzed by the normal mode approach, solved by the regular perturbation technique for linear stability, and the critical internal Darcy–Rayleigh number for the onset of stationary convection has been derived. The paper aims to analyze the effects of parameters like heat source size, depth ratio, Darcy number, throughflow direction, solid fraction, and Prandtl number on stationary convection in a composite air-porous configuration. Understanding these influences can illuminate thermal behaviors in intricate systems and inform applications in heat transfer and fluid dynamics. The observed stability configuration decreases monotonically due to increasing the effect of the depth ratio and solid fraction at any direction and velocity of the throughflow. The thermal and vertical velocity profiles and the results obtained during the analysis have been presented graphically.