Simulations were performed using ANSYS CFX for laminar flow and mixing analysis. The velocities at Inlet 1 and 2 are defined as V1= Vs+ Vo sin (2π f *t) and V2 = Vs+ Vo sin (2π f *t + 180). A no-slip condition was applied at the walls, and zero static pressure was specified at the outlet. The concentrations were set to 0 and 1 at Inlet 1 and 2. A second-order upwind scheme was used to discretize the advection terms; discretization in time was performed using a second-order backward Euler scheme. The criterion for convergence was residual value of 10^-6.