分离式双箱梁绕流场与涡激振动雷诺数效应机理研究

The Reynolds number effect on the wind effects of bridge is a curial scientific issue in Bridge Wind Engineering. Due to the more complicated aerodynamic characteristics, the studies on the mechanism of Reynolds number effect of the long/super-long bridge with twin-box girder become more challenging. For the fundamental problem, the investigations in the project will be carried out through the wind tunnel test, CFD and theoretical analysis. The main structures of the project are as follows:. Firstly, the laws and mechanisms of Reynolds number effects on the flow characteristics around static twin-box girder and VIV will be investigated based on wind tunnel test and directly numerical simulation (DNS) in low and moderate Reynolds number range..Secondly, in the aspiration of flow pattern of flow pasting twin-box girder in low and moderate Reynolds number range, the methods of Large Eddy simulation (LES) on the flow around static twin-box girder and VIV at high Reynolds number will be studied. And the law and mechanism of Reynolds number sensitivity in the high Reynolds number range will also be investigated based on the LES results. Moreover, a uniform mathematical model, which describes the Reynolds number effects on the flow characteristics and VIV of twin-box girder in low, moderate and high Reynolds number range, will be proposed, and a wake oscillator model of VIV will be established based on the control volume method.. Finally, based on the mechanisms of Reynolds number effect on the flow characteristics and VIV of twin-box girder, the wind-tunnel testing approaches on simulating the characteristics of flow around static twin-box girder and VIV at high Reynolds number in ordinary atmospheric boundary layer wind tunnel through the local flow control around twin-box girder will be studied.. The contributions of the project can develop and enrich the theory of bridge aerodynamics. Therefore, the investigations of the project have important theoretical significance and practical value.

桥梁风效应的雷诺数效应是风工程领域极其重要的科学问题，而大跨度桥梁的分离式双箱梁具有更复杂的气动特性，对其雷诺数效应的研究更具挑战性。针对这一基础问题，本项目从风洞试验、CFD数值模拟及理论分析开展研究：首先，通过风洞试验和DNS数值模拟，研究低、中雷诺数下分离式双箱梁绕流场和涡激振动的雷诺数效应规律及其机理；其次，基于低、中雷诺数下分离式双箱梁绕流场模式启发，研究高雷诺数下分离式双箱梁绕流场和涡激振动的LES数值模拟方法及雷诺数效应与机理；建立低、中、高雷诺数下分离式双箱梁绕流场和涡激振动特性统一数学模型及尾流振子模型；最后，基于上述雷诺数效应机理，研究通过局部流态控制在常规大气边界层风洞内模拟分离式双箱梁绕流场和涡激振动高雷诺数效应的方法。本项目研究将发展和丰富大跨度桥梁空气动力学理论，具有重要的理论意义和实用价值。

桥梁风效应的雷诺数效应是风工程领域极其重要的科学问题，而大跨度桥梁的分离式双箱梁具有更复杂的气动特性，对其雷诺数效应的研究更具挑战性。本项目首先提出了一种全新的考虑非局地效应各向异性雷诺应力湍流模型建模方法，并提出了模型参数人工智能深度学习方法。实现了中、低、高雷诺数分离式双箱梁绕流动态亚格子大涡模拟。基于数值模拟结果，研究了分离式双箱梁绕流场流态模式、压力分布和气动力特性随雷诺数的变化规律，揭示了分离式双绕流场流动分离/失稳/转捩是存在雷诺数效应的物理机理。其次研究了低雷诺数下分离式双箱梁涡激振动特性，发现不同风速激发统一阶涡振动现象，揭示了分离式双箱梁涡激振动机理。最后提出了基于监测大数据的大跨度桥梁涡振聚类识别方法，建立了原型桥梁涡振机器学习预测模型，学习得到高雷诺数下足尺分离式双箱梁涡振物理机制和特征。