Instability of Poiseuille Flow in a Bidisperse Porous Medium Subject to a Uniform Vertical Throughflow Effect

In this article, we investigate the influence of the vertical throughflow Reynolds number on the instability of Poiseuille flow in a bidisperse porous medium. The Brinkman model was employed to describe fluid flow in the porous medium with large pores, referred to as "macropores, " while the Darcy model was utilized for fluid flow in the porous medium with small pores, referred to as "micropores." The resulting eigenvalue system was solved using the Chebyshev collocation method, renowned for its accuracy and flexibility, rendering it one of the most reliable methods available. Regardless of its direction, the impact of the vertical throughflow Reynolds number on system instability is not uniform; it exhibits a dual nature, acting as a destabilising factor at specific values while serving as a stabilising influence at others. In the case of the permeability ratio, porous parameter, interaction parameter, and Darcy Reynolds, our observations indicate that elevating these parameters results in an enhancement of system stability.