| 摘要: |
| 应用椭圆余弦波的绕射理论,推导了V形防波堤的浅水波浪绕射解析解,对现有的Airy微幅波理论进行了有效拓展。据此理论对V形防波堤的浅水波绕射作用进行了解析计算,并将几何形状相近的圆弧型防波堤结果加以了对比。结果表明：椭圆余弦波理论计算的V形防波堤最大波浪力和最大绕射波面作用明显大于微幅波理论的对应值。本文方法适用于张角180度的有限长直立薄壁防波堤的浅水波绕射作用计算,从而将无限长直立薄壁堤的反射波理论加以有效拓展。在张角120度的V形堤与圆弧堤的比较中, V形堤施工方便,同因子无量纲总波浪力幅值略低,而堤后防浪效应与圆弧堤相近。在张角90度V形堤与180度圆弧堤比较中,同因子无量纲总波浪力幅值低于张角180度单层密实圆弧堤,而堤后防浪效应比圆弧堤稍差。 |
| 关键词: 椭圆余弦波 V形防波堤 圆弧防波堤 绕射波面 波浪力 散射 |
| DOI：10.11759/hykx20190521001 |
| 分类号:O353 |
| 基金项目:国家重点项目(41407010501),中央高校基本科研业务费专项基金(No.17lgjc41) |
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| Comparison of shallow water wave diffracted effects caused by a V-shaped breakwater and by an arc-shaped breakwater |
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Cai Hantao, HUANG Hua, ZHAN Jiemin
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Department of Applied Mechanics and Engineering,College of Aeronautics and Astronautics,Sun Yat-sen University
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| Abstract: |
| With the use of cnoidal wave theory, the theoretical solutions to shallow water wave diffraction by a V-shaped breakwater are derived, so the existing Airy small amplitude wave theory is extended. Based on that, theoretically calculate the shallow water diffracted effects on V-shaped breakwater. The results show that the maximum dimensionless wave forces and wave surfaces on the V-shaped breakwater are obviously larger than those predicted by small amplitude wave theory under same shallow water conditions. The method given in the paper is suitable to calculate diffracted wave effects on the finite length vertical thin-walled breakwater with the breakwater angle 180o, so the reflected wave theory on the infinite long vertical thin-walled breakwater is effectively extended. The comparison of diffracted effects by a 120 degree V-shaped breakwater and by a 120 degree arc-shaped breakwater shows that V-shaped breakwater is convenient for construction, it has a slightly lower maximum dimensionless wave force under the same dimensionless factors and its wave resistance effects behind the breakwater is similar to that of the arc-shaped breakwater. The comparison of diffracted effects by a 90 degree V-shaped breakwater and by a 180 degree arc-shaped breakwater shows that V-shaped breakwater has a lower maximum dimensionless wave force under the same dimensionless factors however its wave resistance effects behind the breakwater is not as good as that of the arc-shaped breakwater. |
| Key words: cnoidal wave V-shaped breakwater wave force wave diffraction |