Hydrodynamic forces on dual cylinders of different diameters in steady currents

Turbulent flow past two circular cylinders of different diameters is numerically investigated. The two-dimensional Reynolds-averaged Navier–Stokes equations are solved by using a finite element method with a k–ω turbulence closure. Following a relevant numerical model validation process, effects of cylinder gap-to-diameter ratio, the angular position of the smaller cylinder and the diameter ratio of cylinders on the vortex shedding and the forces on the cylinders are investigated using the numerical model. It is found that the relative position of the small cylinder has significant effects on the hydrodynamic force and vortex shedding characteristics of the cylinders.