基于CFD的大跨度桥通载过程颤振稳定性分析

大跨度桥的风致动力响应是抗风设计中的关键问题。为缩短装配式钢桁架桥的设计周期、降低成本，采 用数值模拟的方法对钢桁架桥通载过程颤振稳定性进行分析。采用计算流体力学与动网格技术建立数值风洞，构建 钢桁架桥通载过程的2 维仿真模型，模拟桁架桥通载过程的分状态强迫振动，以2 维3 自由度耦合颤振分析方法为 理论依据，仿真分析某型装配式钢桁桥通载过程的断面绕流场和桥梁上颤振自激励，识别出颤振导数，并得到通载 过程颤振临界风速。结果表明：仿真结果与风洞实验结果一致，证明该方法是可行、可靠的，可为以后工程应用奠 定基础。

Flutter Stability Analysis of Long-span Bridge Traffic Capacity Process Based on CFD

Wind dynamic action to long-span bridge is the key problem in the wind resistant design. To shorten the design cycle and lower the cost of a fabricated steel truss bridge, and by use of the numerical wind tunnel established by computational fluid dynamics (CFD) and dynamic mesh technology, the 2-D numerical model of the fabricated steel truss bridge in the traffic capacity process is established. The detached-forced vibration of the traffic capacity process are simulated, based on two-dimensional 3 DOF coupling flutter method (2d-3DOF method), the flow field characteristics, flutter derivatives and critical flutter speed of the fabricated steel truss bridge in the traffic capacity process are obtained. The result shows that the result of numerical simulation is consistent with the wind tunnel experiment. So, the method is feasible and reliable. The foundation for its further application in practical projects is laid.