Abstract:The expressions of flutter derivative described by the surface pressure of model were derived in this work. In combination with the computational fluid dynamics (CFD), the surface pressure of model was achieved, the calculation method of pressure amplitude and phase difference in the expression of flutter derivative was analyzed, and the influences of surface pressure distribution characteristics on flutter derivatives and flutter stability were studied. By reasonably zoning the model, the contributions of different zones to the flutter derivatives were discussed, and furthermore, the vibration suppression principle of the central stabilized plate was analyzed. The research results show that the asymmetric distribution of vortexes on the upper and lower surfaces of girder with H-shaped section leads to the asymmetric distribution of the mean pressure on the model surface and the clockwise torque on the model. When the wind speed is lower than the critical wind speed of flutter, the pressure greatly affecting the flutter derivative A*2 may lead to the counterclockwise torque on the model, so as to maintain the balance of the vibration system. When the critical wind speed of flutter is reached, the distribution pressure affecting the flutter derivative A*2 may lead to the clockwise torque, which undermines the stability of system.
刘祖军 葛耀君 杨詠昕. 形断面的压力分布特性对其颤振性能的影响[J]. 土木工程学报, 2017, 50(6): 71-78.
Liu Zujun Ge Yaojun Yang Yongxin. Characteristics of pressure distribution on H-shaped section and its influence on the flutter performance. 土木工程学报, 2017, 50(6): 71-78.