Numerical study on an unsteady flow of an immiscible micropolar fluid sandwiched between Newtonian fluids through a channel

This paper deals with an unsteady flow of a micropolar fluid sandwiched between Newtonian fluids through a horizontal channel. The governing time-dependent partial differential equations are solved numerically by using the Crank–Nicolson finite difference approach. The continuity of velocity and shear stress is considered at the fluid-fluid interfaces. It is observed that the fluid velocities increase with time; eventually, a steady state is reached at a certain time instant. The velocity decreases with increasing micropolarity parameter in the micropolar fluid region and remains almost unchanged in both Newtonian fluid regions.