We study the temporal distribution of wave energy in a wave field that is generated by the reflection of a wave spectrum from a vertical wall. Weakly nonlinear wave fields over finite, constant depth are considered, and the reflection induces large correlations between different wave components of the wave field. The nonlinear time evolution of such an inhomogeneous random wave field is studied by means of an equation developed by Crawford, Saffman and Yuen in 1980. We show that, depending on the spectrum and the water depth, there is a significant increase in the probability of freak waves, whose height is more than twice the significant wave height, created by the reflection off the wall.

我们研究波场中波能量的时间分布，该波场是由垂直壁反射波谱而产生的。考虑了有限、恒定深度上的弱非线性波场，并且反射导致波场的不同波分量之间存在较大的相关性。借助 Crawford、Saffman 和 Yuen 在 1980 年开发的方程，研究了这种非均匀随机波场的非线性时间演化。异常波，其高度是有效波高度的两倍以上，由墙壁反射产生。