湖区桥塔塔顶表面风压的数值模拟

Numerical simulation of wind pressure on bridge tower top surface in lake district

以洞庭湖大桥桥塔(主塔)为研究对象,基于Fluent软件平台,模拟了主塔塔顶表面的风压分布。采用3种不同的湍流模型对主塔塔顶进行数值模拟,并将模拟结果与实测试验结果进行了对比。选取合理的湍流模型;并探讨了不同风速及不同风向角对主塔塔顶表面风压分布的影响。结果表明,3种模型模拟的结果均与实测试验结果变化趋势一致,而Realizable k-ε模型的模拟结果更接近于实测试验结果;不同风速对主塔塔顶迎风面及侧面风压系数影响较小,而对其背风面风压系数有较明显影响;不同风向角对主塔塔顶风压系数影响显著,尤其是对其拐角处。研究结论可供湖区复杂高耸结构的抗风设计参考。

Based on Fluent software platorm the surface wind pressure distribution of big bridge tower （ main tower） top of Dongting Lake was simulated. The surface wind pressure distribution of the main tower top was simulated by three different turbulence models, and compared with the observed or experimental values, we select the reasonable turbulent model, discussed the influence of different wind velocity and wind direction on wind pressure distributions of main tower top surface. Results show that the results simulated by all three kinds of model are consistent with the experimental results, the simulation results of Realizable k-ε model is more close to the experimental results ; different wind velocities have less influence on wind pressure coefficients of windward side and the side of tower top, and the influence on the wind pressure coefficient of leeside is obvious. Different wind directions have a greater influence on the wind pressure coefficients of the main tower top ; especially for its corner. The obtained results my give reference to wind resistance design of the complex - shaped high - rise structure in lake district.