Aerodynamic behavior of inclined circular cylinders-cable aerodynamics

Abstract This study attempts to clarify of the mechanism of rain-wind induced vibration of the stay cables of a cable stayed bridge and to find an effective aerodynamic stabilization method. Through a series of wind tunnel tests the fundamental aerodynamic characteristics of a yawed and/or inclined circular cylinder with and without rain were investigated. An intense secondary axial flow was found to form in the early wake, playing a similar role to that of a splitter plate submerged in the wake. This axial flow resulted in an aerodynamic exciting force acting on the yawed and/or the inclined circular cylinder. The role of rain in the rain-wind induced vibration of the stay cable is shown to be that of an amplifier of the essential unstable aerodynamic exciting force acting on the yawed and/or the inclined circular cylinder. The role of rain the rain-wind induced vibration of the stay cable is shown to be that of an amplifier of the essential unstable aerodynamic characteristics of the yawed and/or the inclined circular cylinder. Aerodynamic stabilization should depend essentially on controlling this characteristic secondary flow.