中国海洋大学学报（自然科学版）2018，Vol.48Issue(2)：96-104,9.DOI:10.16441/j.cnki.hdxb.20150314
不同尺度人工岛波浪绕射系数的研究
Study on Wave Diffraction Coefficients of Artificial Island with Different Scales
摘要
Abstract
Artificial island is a large structure in coastal engineering.The determination of design wave height has a close relation with wave diffraction.Although the Code of Hydrology for Sea Harbor (JTS145-2-2013) proposes a method to calculate the height of diffracted wave in shield region of coastal structure,the Code's method does not consider the effect of structure scales along wave propagation direction.In fact,the wave diffraction coefficients differ in the shield area due to the change of structure scale.In this paper,in order to study the wave diffraction coefficients of artificial island with different scales,MIKE21-BW model is employed to simulate the wave field with different structure scales.The isolines of diffraction coefficients in the shield area with different scales of artificial island are drawn based on the simulated results.The wave diffraction coefficients of artifidal island with different scales are compared with experimental data as well as the results obtained by the Code's method.The effects of structure scales to diffraction coefficients of the shield region are then analyzed.MIKE21-BW model is an efficient model to study the combined effects of most wave phenomena,including shoaling,refraction,diffraction,partial refection and transmission and so on.The model includes two types of the Boussinesq equations,i.e.,the enhanced Boussinesq equations and the classical Boussinesq equations.In this paper,the enhanced Boussinesq equation is used.In simulating,conditions of the incident wave are supposed the same as Briggs' physical experiment and the Code's,respectively.The values of diffraction coefficients obtained by simulation agree well with experimental data,while,the values obtained by simulation with no consideration of structure scales along wave propagation direction differ quite small from results by the Code's method.The comparison results can verify the applicability of BW model for this study.In order to study the effect of structure scales along wave propagation,this paper simulates 7 cases of different structure scale,i.e.,the length of artificial island along wave propagation is 0.5Ls Ls,2Ls,3Ls 4Ls 5Ls and 6Ls,respectively.The following results are then obtained from the simulation:(1) Diffraction coefficients become bigger with the increase of scales from 0.5Ls to 2Ls;(2) Diffraction coefficients become slightly smaller with the increase of scales from 3Ls to 6Ls;(3) Diffraction coefficients vary relatively obvious in the area near island and island-shielded region;(4) The scales of artificial island has definite effect on values determination of diffraction coefficients.In this paper,the isolines of diffraction coefficients with different island scales are given,which can be references for calculating the diffracted wave height.关键词
BW模型/人工岛/绕射系数/尺度/数值模拟Key words
BW model/artificial island/diffraction coefficients/scales/numerical simulation分类
建筑与水利引用本文复制引用
于定勇,李龙,张广成..不同尺度人工岛波浪绕射系数的研究[J].中国海洋大学学报（自然科学版）,2018,48(2):96-104,9.基金项目
山东省自然科学基金项目(ZR2013EEZ002)资助 Supported by Natural Science Foundation of Shandong Province(ZR2013EEZ002) （ZR2013EEZ002）
