海洋双桩基础周围流场特征数值模拟

Numerical Simulation of Flow Field Characteristics Around Offshore Double-Pile Foundation

开展双桩基础周围三维流场的数值模拟,计算分析不同桩间距、入流角度对桩周流场结构的影响。研究发现:在稳定单向流作用下,双桩周围出现壅水、向下冲击水流、立轴状小漩涡等流场结构;并联双桩间距0.5 D时,涡流在双桩内部剪切层发展,增大到3 D后双桩交互干扰显著减弱;串联双桩之间的干扰以尾流效应为主,漩涡脱落呈现反对称,且底部干扰较上部更为明显;45°布置两桩,其存在前后和上下两剪切层,涡量分布非常复杂。

The numerical simulation of the three dimensional flow field around the double pile foundation is carried out.The influence of different pile spacing and inflow angles on the flow field structure of the double pile foundation is studied.It is found that under the stable unidirectional flow,some flow structures appear,such as backwater,downward impact of water,vertical small whirlpool.When the parallel pile spacing is0.5D,the eddy current develops in the internal shear layer of the double pile,and the interaction between two piles is significantly weakened when the spacing is increased to3D.The interference between two piles in series is dominated by the wake effect,and the vortex shedding is asymmetric.The bottom disturbance is more obvious than the upper part.For45°arranged double pile,there are front back and upper lower shear layers,and the vortex distribution is very complex.