Aerodynamic Forces Numerical Estimation for Cross Flow Over Three Circular Cylinder Inline Arrangement

Abstract

A two-dimensional numerical simulation was performed using the program (Ansys-Fluent 22.1), for air flow around three circular cylinders to get the knowledge of the characteristics of aerodynamic forces (drag & lift) where they are arranged in tandem at various ratios of spacing (L/D =1, 1.2, 1.5, 2, 3, 45) for constant Reynolds number (Re =1171). This study was done using the turbulence model (k-? SST). The findings demonstrated that there is vortex simple shedding when spacing ratios where (L/D=1, 1.2, 1.5), vortex shedding begins when spacing ratios (L/D=2, 3), while when spacing ratio (L/D=45) the cylinders behave as if they were a single and independent cylinder because of the big distance of the cylinders from each other. Also, the pressure coefficient values for the first cylinder are greater than the pressure coefficient values for the second and third ones, the drag coefficient values for the first cylinder are positive and greater than the drag coefficient values for the second and third cylinders in all the study cases, the pressure fluctuations and the vortex shedding affecting the lift coefficient values so it oscillates between positive and negative and are close to be zero.