波浪在陡坡上的传播变形

WAVE PROPAGATION AND TRANSFORMATION ON STEEP SLOPE

利用数值方法和物理模型分析以反射为主的陡坡上波浪传播变形特性。数值方法采用标记单元法，为处理倾斜反射边界对斜坡前波浪运动的影响，提出了“台阶镜像法”。通过1：1．5光滑斜坡上物理模型试验，分析了不完全立波的运动特性，说明强反射光滑陡坡坡前波浪运动呈明显的立波状态，它与直墙反射的主要差别是被前第一波节点和腹点位置向岸推移。本试验得到的波浪反射、爬高和回落特征值与港口工程规范给定结果接近。

Wave Propagation and transformation characteristics on a steep slope where the reflection is dominant are analysed by a numrical and a physical model. For the numrical method the Marker and Cell technique is used and the Stage Mirror Image skill is proposed for dealing with the influence of the incline reflection boundary on the wave motion in front of the slope. The slope boundary is replaced approximarely by a stage net An invented propagation area is set up whose stage incident boundary is symmtrical about the slope net Return the wave propagation direction along the invented area and add them to the incident wave propagating in the real area in the front of the slope, the wave propagation and transformation process consisting of the influence of the slope can be modelled. The kinematic characteristics of thepartial standing wave are analysed by the Physical model on the 1:1. 5 smooth slope. The Partial standing wave can be decomposed into a standing wave formed by the reflecting component of the incident wave and a propating wave formed by its non-reflecting component The characteristics of wave propagation and transformation on the slope are determined by the proportion of these two componnts. For the smooth steep slope with strong reflection, the wave motion in front of the slope is in obvious standing wave state. The difference between the wave reflection by a slope and tha by a vertical wall is that in the first case the positions of the first node and antinode move toward the bank The measured results for the reflection coefficient runup and rundown on the 1:1.5 smooth slope are close to calculated values obtajned by using the technical code of port engineering of the Ministry of Communication