近岸浅水波的计算

CALCULATION ON NEARSHORE SHALLOW-WATER WAVES

采用理论推导与实验资料验证相结合的方法对近岸浅水波衰减计算进行研究。研究表明，波浪与浅水区运动传播衰减是各种能耗共同作用的结果，为此总结了分子粘性能耗、湍流能耗、底部渗透能耗、底部摩擦能耗、软尾海底弹性能耗等，由建立波能流平衡方程出发进行理论推导，得出各种能耗影响下波浪衰减的计算公式，并将该理论公式与作者1980年波浪水相试验资料比较，两者基本吻合，可适用干线性及非线性各种波能耗情况的计算。

This paper analyses the various energy dissipations of waves propagating in ne-arshore shallow-water areas. These dissipations of molecular viscosity, turbulence,laminary viscosity in boundary layer of bottom, bottom penetration, bottom friction-al drag, and soft bottom elasticity can be divided into one type that is proportional to the unit power of the wave energy (called linear energy dissipation) and another type that is proportional to the 1.5-th power of the wave energy (called non-linear energy dissipation). In some early studies, only a certain main energy dissipation mentioned above was considered for briefness, while the others were neglected. As a result, the attainab1e precision is rather low, and the resulting value differs far from the objective reality. This work considers the comprehensive effects of all wave energy dissipation by establishing a balance equation of wave energy current. The ca1culating formu1a for the wave decay resulting from all energy dissipatiolls can be obtained by means of theoretical derivation. For areas mainly affected by linear ene-rgy dissipatioll, the formula can be simplified. This theoretical formula is very con-sistent with the lab observation data.