DYNAMIC-RESPONSE OF THE FLOW-INDUCED VIBRATION OF SMOOTH AND ROUGH SINGLE CANTILEVER CIRCULAR-CYLINDERS

The effects of surface roughness and turbulence intensity on the dynam ic characteristics of flow induced oscillation of a cantilever single circular cylinder in a cross air flow were experimentally investigated . Measurements of the dimensionless vibration amplitude in the transve rse (lift) and streamwise (drag) directions were undertaken and found to be very much dependent on both freestream turbulence intensity and surface roughness. It was found that, in general, increasing the turbu lence intensity tends to increase the vibration amplitude in the trans verse direction and to decrease it in the streamwise direction. The ef fect of surface roughness is to reduce the dimensional vibration ampli tude in both directions.