The Turbulence Intensity Effect on the Flow Characteristics and Aerodynamics of a Circular Cylinder

Abstract

In this investigation, a numerical study about the turbulence intensity effect on the time-dependent flow structure around a circular cylinder employing k-ω based Detached Eddy Simulation (DES) turbulence model was performed at sub-critical Reynolds number of Re=5×10 3 . According to the numerical analyses, the length of recirculation region reduces as the level of turbulence intensity augments. While the normalized length of recirculation region after the cylinder, L s /D is measured as 1.225 at turbulence intensity of Tu=0.8%, it reduces to the value of L s /D =1.0822 at turbulence intensity of Tu=7%. Furthermore, the location of peak negative pressure coefficient moves in downstream direction by increasing turbulence intensity. The drag coefficient, C D was observed to increase when turbulence intensity increases from Tu=0.8% to 7% and 12%. Thus, it was concluded that the level of turbulence intensity is effective on changing the flow characteristics and aerodynamics of a circular cylinder.