双色波数值模拟的造波方法研究

Study on bichromatic wave numerical simulation-based wave-generating method

为了使数值波浪水槽模型能够精确简便地代替物理模型,并为港口海洋工程及内河工程提供重要的数据支持,基于不可压缩黏性流体的N-S方程和VOF方法,运用软件FLUENT建立数值水槽。通过对软件的二次开发,进行推波板造波方法的波浪数值模拟。将物理模型实验中的Sch?ffer二阶造波理论运用于波浪数值模拟,实现基于二阶推波板造波法的双频波数值模拟。在此造波基础上,开创性地模拟出变化地形下波浪的相互作用,体现出其非线性作用。研究结果显示:(1)将各工况得出数据分别与理论值和实验值进行对比验证,表明所用方法有较好的精确性;(2)通过双色波相互作用后的频域分析得出其适用范围为0.1<h/L<0.5。推波板造波法模拟的数值波浪有着较好的非线性和精确性,可以在一定条件下代替物理实验。

In order to make the numerical wave flume model accurate and simple for replacing the physical model and provide important data support for port and ocean engineering and inland river engineering,a numerical flume is built up with the software of FLUENT based on N-S equation of incompressible viscous fluid and VOF method.Through the secondary development of the software,a numerical simulation on the wave made by the method of wave-pushing plate is carried out.The Sch?ffer second-order wave-generating theory in the physical model experiment is applied to the numerical simulation of the wave,and then the second-order wave-pushing plate wave-generating method-based numerical simulation of dual-frequency wave is realized.On this wave-generating basis,the wave interaction under the condition of changed landform is initiatively simulated,which reflects its nonlinear effect.The study result shows that(1)through comparing the data obtained from all the working conditions with both the theoretical values and the values from the relevant experiment,it is demonstrated that this method has a better accuracy;(2)through the frequency domain analysis made after the bichromatic wave interaction,it is obtained that its applicable range is 0.1<h/L<0.5.The numerical wave simulated by the method of wave-pushing plate has better nonlinearity and accuracy,and then can replace the relevant physical experiment under certain conditions.