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当细长结构的驰振临界风速位于涡激共振风速锁定区间内或者接近时,存在涡激共振与驰振两种不同类型风振现象耦合的可能。该文对这两种振动耦合进行了理论推导并建立了相关的耦合振动预测模型;根据3个大长细比钝体构件的工程实例,通过数值模拟和风洞试验等手段获得的相关风振参数分别估算了两类振动的临界风速与锁定区间。由风洞试验测得的构件实际振动曲线与预测模型吻合良好,从而证实了一定条件下构件涡激共振和驰振存在耦合的可能,定性地说明了在两种不同振动机理下产生的气动负阻尼会相互叠加并共同抵消结构机械阻尼,使涡激共振幅值增大,驰振临界风速提前。
When the vibrational critical wind speed of the slender structure is located within or close to the locked range of the vortex-induced resonance velocity, there is a possibility that two different types of wind-vibration phenomena, vortex-induced vibration and galloping, may be coupled. In this paper, the theoretical coupling of these two kinds of vibration is theoretically deduced and the related coupled vibration prediction model is established. According to the engineering examples of three large slenderness ratio bluff body components, the relevant wind vibration obtained through numerical simulation and wind tunnel test The parameters estimate the critical wind speed and lock interval of the two types of vibration respectively. The actual vibration curve measured by the wind tunnel test is in good agreement with the prediction model, which proves the possibility of the coupling between the vortex-induced resonance and the vibration-induced vibration of the component under certain conditions. The negative aerodynamic negative effect of two different vibration mechanisms Damping will be superimposed on each other and work together to counteract the mechanical damping of the structure, so that the amplitude of the vortex-induced resonance increases and the critical vibration speed of the vibration-on-vibration is advanced.