This work consists to study numerically the phenomena of two-dimensional incompressible laminar flows around two tandem circular cylinders of various diameters. Five cases of flow with various hydraulics diameters are simulated. The first cylinder has a fixe diameter D, while the diameter of the second will change between D/4 and 4D, the distance between cylinders is fixed at L=4D. From these simulations, particularly in the area of interference and downstream wake area of the cylinder, the results demonstrate clearly the influence of the diameter on the flow structure. We visualized the phenomenon of Van Karman, the behavior of fluid particles is characterized by sudden destruction of the vortices downstream of the wake. To provide a better understanding of the dynamics of vortex, the pressure distribution contours, velocities depending on the diameter and the Reynolds number, Re are presented and discussed.
فاتح مبارك اودينة | Mebarek Oudina Fateh | 11117