基于LBM的波浪作用下动量射流数值模拟

Numerical Simulation of Momentum Jets under Wave Action Based on LBM

为了进一步研究射流在有限水深波浪环境下的流动规律,拓宽LBM在水利工程学科中的应用范围,将LB方法的原理应用于自由表面处理、边界条件设定、紊流模型的耦合求解、造波及消波等关键问题上,建立了二维多松弛LB数值波浪水槽模型。运用该模型模拟不同波浪环境下动量射流的紊动特征及变化规律,得到射流在不同工况下的轴线速度衰减、扩展半宽变化和横断面速度分布等规律。研究表明,该模型具有很好的适用性,可以较好地模拟射流问题。

For further researching the flow discipline of jet in the limited water depth wave environment,as well as widening the application of the Lattice Boltzmann Method（LBM）in water conservancy fields,a 2 D multi-relaxation LB numerical wave tank model was established,which applied the principle of the LB method to processing the free surface,setting boundary condition,coupling of the turbulence model,wave making and eliminating as well as other key issues.The model was used to simulate the turbulence feature and the variation discipline of the momentum jet in different wave environments.The jet laws of axis velocity attenuation,extended half-width variation and cross sectional velocity distribution was obtained under different working conditions.The results show that the model is applicable to simulate the jet flow problems.