Violent breaking wave impacts. Part 2: modelling the effect of air
Violent breaking wave impacts. Part 2: modelling the effect of air
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DOI：
10.1017/s0022112009991571
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发表时间：
2009-12-25
影响因子：
3.7
通讯作者：
Bullock, G. N.
中科院分区：
文献类型：
--
作者：
Bredmose, H.;Peregrine, D. H.;Bullock, G. N.
当海浪冲击陡前防波堤、海堤或类似的海洋结构物时，其对结构物的冲击可能非常剧烈。本文介绍了理论研究，连同现场和实验室调查，已经进行了，以获得更好地了解所涉及的过程。波的方法对结构建模与经典的无旋流，以获得不同类型的影响，可能会或可能不会导致空气截留的个人资料。随后的影响是仿照一个新的可压缩流模型的均匀混合物的不可压缩液体和理想气体。这使得被困气穴和压力冲击波通过充气水的传播的数值描述。一个精确的黎曼求解器的开发，以允许一个有限体积的解决方案的流动模型与最小可能的局部error.The高压力测量波的冲击期间的防波堤重现，它表明，被困的空气可以被压缩到几个大气压的压力。压力冲击波从海底等附近表面反射回来，可产生与撞击相当的压力。压力-时间历程，力和脉冲的典型例子，并讨论其实际意义。所提出的数值模型是相关的各种流动的空气效应是重要的。进一步的应用，包括扩展的研究波的影响，进行了讨论。
When an ocean wave breaks against a steep-fronted breakwater, sea wall or a similar marine structure, its impact on the structure can be very violent. This paper describes the theoretical studies that, together with field and laboratory investigations, have been carried out in order to gain a better understanding of the processes involved. The wave's approach towards a structure is modelled with classical irrotational flow to obtain the different types of impact profiles that may or may not lead to air entrapment. The Subsequent impact is modelled with a novel compressible-flow model for a homogeneous mixture of incompressible liquid and ideal gas. This enables a numerical description of both trapped air pockets and the propagation of pressure shock waves through the aerated water. An exact Riemann solver is developed to permit a finite-volume solution to the flow model with smallest possible local error.The high pressures measured during wave impacts on a breakwater are reproduced and it is shown that trapped air can be compressed to a pressure of several atmospheres. Pressure shock waves, reflected off nearby surfaces such as the seabed, can lead to pressures comparable with those of the impact. Typical examples of pressure-time histories, force and impulse are presented and discussed in terms of their practical implications. The numerical model proposed is relevant for a variety of flows where air effects are important. Further applications, including extended studies of wave impacts, are discussed.