大振幅波非线性传播的频率特性

Frequency characteristics of nonlinear propagation of large amplitude waves

为研究大振幅波在介质中非线性传播的频域能量变化问题,采用频谱分解方法对单频及多频大振幅的传播规律进行了分析.对不同形式的单频大振幅波传播过程中的基频波能量变化及谐波幅度增长情况进行了比较;同时分析了多频大振幅波非线性传播过程中,各频率声波相互作用情况,通过仿真研究了影响基频波能量变化的因素,其中高频波频率是影响基频波能量变化的主要因素,并通过谱分解方法得到了多频大振幅球面波和柱面波的非线性传播规律.

To find changes in energy in the frequency domain when large amplitude waves propagate,the propagation of single frequency and multi-frequency large amplitude waves was studied by the spectrum decomposition method.Changes to the fundamental frequency energy and the harmonic wave amplitude when different forms of single-frequency large amplitude wave propagated were compared.Nonlinear interactions of the various frequency waves were analyzed,given nonlinear propagation of the multi-frequency large amplitude waves.The influence of changes to the parameters on the energy of fundamental frequency waves were calculated with a simulation.The frequency of high frequency waves was the main factor affecting the fundamental frequency of wave energy.The nonlinear propagation of multi-frequency large amplitude spherical waves and cylindrical waves was then also studied by spectral decomposition.