Effect of turbulence intensity on the aerodynamic forces and flow field characteristics of a circular cylinder at Re = 3900

This study presents numerical simulation data for a flow over a cylinder subjected to turbulent inflow at Reynolds number of 3900; turbulence intensities ranging from 1.3% to 8.8% are considered. The influence of the turbulence intensity on the aerodynamic forces and flow field around the cylinder is comprehensively studied using the large eddy simulation approach. Key parameters such as the force coefficients, wind pressure distribution, Strouhal number, and instantaneous and average flow fields are analyzed to provide a theoretical reference for the designing and constructing cylindrical structures in turbulent environments. The results show that increasing the turbulence intensity suppresses vortex shedding and flow separation, causing an unstable vortex shedding frequency from the cylinder. Wake vortices exhibit multi-frequency shedding with high energy, and the mean drag coefficient increases linearly. The Strouhal number decreases sharply when the turbulence intensity reaches 7.5%. Additionally, the recirculation zone in the cylinder wake is reduced, negative pressure on the leeward and side surfaces increases, fluctuating pressure exhibits enhanced Gaussian characteristics, and disturbance of the cylinder to the flow field is weakened.