不规则波作用下的港域波浪条件试验研究

Experimental study on wave conditions in harbor area under irregular wave

针对数学模型很少能较好地模拟天然海浪的多向性、不规则性的特点,基于港口波浪整体物理模型试验,对不规则波作用下港域内测点的波高扰动系数的分布规律进行研究。结果表明:在绕射作用为主的掩护区域,多向波的绕射性能大于单向波,波浪扰动系数较大;波浪绕射、反射作用均十分强烈的掩护区域,多向不规则波与单向不规则波的扰动系数看不出明显的大小关系。以反射作用为主的掩护良好区域,单向不规则波的扰动系数较多向不规则波的要大,且受反射作用越大的区域,单向波的扰动系数大的越多。在以绕射作用为主的掩护区域,波浪分布对周期的敏感性较差;在以反射作用为主的掩护良好区域,波高分布对周期的敏感性较强。在绕射、反射都较强的情况下有可能单向波作用下的港内波高大于单向波,用单向不规则波来模拟反而是偏安全的。在进行港内波况整体模型试验时需要根据实际的工程条件做出综合考虑来决定波型,必要时要对单向、多向不规则波都要进行试验以确定最佳方案。

At present,the numerical model can hardly simulate the characteristics of the multi-directional andirregular nature of the natural wave.Based on the overall physical model test of the port wave,we study thedistribution law of the wave height disturbance coefficient of the measured point in the harbor under the action of theirregular wave.The results show that in the shielding area dominated by the diffraction effect,the diffractionperformance of the multi-directional wave is greater than that of the unidirectional wave,and the wave disturbancecoefficient is larger.Wave diffraction and reflection are very strong coverage area,multi-directional irregular waveand unidirectional irregular wave disturbance coefficient cannot see the obvious size relationship.In the well-coveredarea dominated by the diffraction,the disturbance coefficient of unidirectional irregular wave is larger than that ofmulti-directional irregular wave,and the larger the reflection coefficient is,the larger the disturbance coefficient ofunidirectional irregular wave is.In the shield area dominated by the diffraction,the wave distribution is less sensitiveto the period.The wave height distribution is more sensitive to the period in the well-covered area which isdominated by the reflection.In the case of diffraction and reflection,it is possible that the wave height in the portunder unidirectional wave is larger than that of unidirectional wave,and it is safe to use unidirectional irregular waveto simulate it.In the case of the overall model test,it is necessary to make a comprehensive consideration based onthe actual engineering conditions to determine the wave type.If necessary,two kinds of unidirectional and multidirectionalirregular waves should be tested to determine the best scheme.