风、浪、流多场耦合作用波浪传播演化机理对比分析

Comparative analysis of the mechanism of wave propagation and evolution under the coupling effect of wind,waves,and currents

风、波浪与海流在海洋环境中具有强烈的耦合性,准确描述波浪在耦合场中的传播规律尤为重要。为揭示风、流与浪耦合工况的实时演化机理,本文采用Fluent构建数值波浪水池,改进了风-浪耦合边界自由液面处风与水质点速度方向的一致性;在此基础上,研究了各工况波浪传播的时空演化规律并分析了水质点速度分布特性,最终提炼出风、浪、流多场耦合机理。结果表明:提出的改进边界风-浪耦合造波技术具有良好的稳定性和有效性;风-浪耦合后波谷下沉导致二阶Stokes波不再保持“谷坦”特征,浪-流耦合导致波高显著减小、波长变长,并伴随出现波群现象;各工况水质点在水平和竖向速度的相位分布呈现花束状,同时在T0、T4相位分别达到正向、负向加速度极值。

Wind,wave,and current are strongly coupled in the marine environment,and accurately describing the wave propagation law in a coupled field is important.To reveal the real-time evolution mechanism of wind,current,and wave coupling conditions,Fluent is used for constructing a numerical wave tank.First,the consistency of the direction of the wind and water particle velocities at the free surface of the wind-wave coupling boundary is improved.Subsequently,on this basis,the time-space evolution law of wave propagation under various working conditions is investigated,and the velocity distribution characteristics of water particles are analyzed.Finally,the multifield coupling mechanism of wind,waves,and currents is extracted.Results show that the improved boundary wind-wave coupling wave-making technology proposed herein has good stability and effectiveness.After the wind-wave coupling,trough subsidence causes the second-order Stokes wave to neglect the characteristics of“flat troughs.”Wave-current coupling,along with the wave group phenomenon,causes the wave height to decrease significantly and the wavelength to increase.The phase distributions of water particles under each working condition at the horizontal and vertical velocities present a bouquet shape;simultaneously,they reach the extreme values of positive and negative accelerations in phases T and T,respectively.