Experimental study on aerodynamic characteristics of a wavy cylinder

The wind load and wind-induced vibration of stay cables are prominent. It is of great significance to explore a new type of stay cable which can not only reduce drag force but also suppress vibration. It is reported that a wavy cylinder has the capability of reducing drag force and suppressing vibration at Reynolds number of 103-104. In fact, the Reynolds number of stay cables is actually 105. It is necessary to examine the aerodynamic performance of a wavy cylinder at high Reynolds number. Taking a wavy cylinder with specific geometric parameters as the research object, the aerodynamic characteristics during Reynolds number of 1.4 ×105-4. 0×105 were studied through a wind tunnel test. The results show that the drag force coefficient of the wavy cylinder is larger than that of a uniform cross section cylinder. During the Reynolds number of 1.4×105-3. 6×105, value is around 4%-8%. The value is up to 47% in 3.6×105-4. 0×105. In critical Reynolds number region, the drag force coefficient of the wavy cylinder does not experience sharply declining which belongs to the transition from pre-critical regime (TrBL0) to one bubble regime (TrBL1). However, the drag force coefficient maintains stable with the increasing of Reynolds number. And the lift coefficient is always near 0 during whole tested Reynolds number. The variation of drag force coefficient, lift force coefficient, and wind pressure distribution with Reynolds number at different spanwise locations behave differently, which is mainly due to 3D geometric characteristics of the wavy cylinder. © 2021, Editorial Office of Journal of Vibration and Shock. All right reserved.