多消浪室开孔沉箱消浪特性的数值模拟研究

Numerical Simulation of Wave Absorbing by Multi-Chamber Perforated Caissons

本文基于雷诺平均的Navier-Stokes方程和k-ε模型求解湍流流动,采用流体体积法(Volume of Fluid,VOF)追踪自由表面运动,建立无反射波浪数值水槽,对多消浪室开孔沉箱的消浪特性进行数值模拟研究。将单消浪室和多消浪室开孔沉箱反射系数和结构前波面分布的数值分析结果与物理模型试验结果进行对比验证,两者符合良好。利用数值算例,研究多消浪室开孔沉箱的反射特性以及开孔结构附近的速度场和湍流强度分布。分析结果表明:波浪与开孔沉箱相互作用时,涡旋和湍动主要分布在开孔墙和消浪室内部自由表面附近;与单消浪室开孔沉箱相比,多消浪室开孔沉箱可以更有效的耗散波浪能量,降低结构的反射系数。本文分析结果可为开孔沉箱结构的工程设计提供参考依据。

A numerical model,based on the Reynolds Averaged Navier-Stokes(RANS)equations with a k-εturbulence model,was used to study the wave absorbing by multi-chamber perforated caissons.The free surface motion is tracked by the Volume of Fluid(VOF)method.The numerical results of the reflection coefficient and the surface elevation near the perforated caissons are compared with experimental data in literature,and the agreement between numerical and experimental results is good.Then the velocity field and turbulence intensity distributions around the multi-chamber perforated caissons are analysed.The numerical results show that the vortices and turbulence mainly occur in the vicinity of perforated walls and the free surface inside the wave chamber.Compared with the single-chamber perforated caisson,the multi-chamber perforated caisson may dissipate more incident wave energy and has a lower reflection coefficient.The main results obtained in this study can provide useful reference for the engineering design of perforated caissons.