弯曲河道方形桥墩紊流宽度数值模拟

弯曲河道流态复杂,修建桥梁后桥墩对河道流场改变较大,对船舶航行安全非常不利。采用格子Boltzmann方法模拟桥墩三维紊流流场,并结合大涡模拟和运动边界处理方法,分析不同来流、弯曲半径等条件下的方形桥墩三维紊流宽度,由此建立了相对紊流宽度与弗劳德数之间耦合关系。利用上述成果,以四川新西林大桥为例进行验算,并与长江航道规划设计研究院的研究成果比较。结果发现,该方法得出的桥墩紊流宽度略大,但数值趋于合理。

Numerical simulation of turbulent flow width of curved channel square pier

The flow state of the curved channel is complicated,and the bridge pier is a great change to the flow field of the river,which is very bad for the navigation safety of the ship.In this paper,the three-dimensional turbulent flow field of the pier is simulated by the lattice Boltzmann method,and the three-dimensional turbulence width of the square piers under different flow and bending radius is analyzed by using the large eddy simulation and the motion boundary treatment method.Therefore,the coupling relation between the relative turbulence width and Froude number is established.Based on the above results,the study of Xinxilin Bridge in Sichuan province is carried out and compared with the research results of Changjiang Waterway Planning and Design Institute.The results show that the turbulent flow width of the pier is slightly larger,but the numerical value tends to be reasonable.