Abstract Maritime structures operating out at sea experience large changes in wetted area because of free surface waves. Although these conditions are typical for maritime applications, a fundamental experiment that includes a structure in the air–water interface undergoing transitions from dry to wet and back does not appear to exist. This paper aims to fill that knowledge gap. We present an experiment in which a pendulum is suspended just above the still water level and then exposed to monochromatic free surface waves with different wave lengths. Additionally a reduced-order model is derived to compute the response of the pendulum and help interpret the experimental results. The motion response of the pendulum is demonstrated to depend highly on whether the wave period is much lower or higher than the dry natural period of the pendulum. Additionally, a sensitivity study with the wave amplitude in the model and a quantification of the variability in the experiment both indicate that the variability in the motion response of the pendulum is increased with respect to the variability of the incoming wave. We believe this experiment and the results make for an interesting benchmark of fluid–structure interaction in free surface waves. The properties of the pendulum and the experiment are available as open data at doi:10.4121/13187594 (Wellens and Bos, 2020).

中文翻译：

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钟摆和单色波之间的流固耦合

摘要 由于自由表面波，在海上作业的海上结构会经历较大的润湿面积变化。尽管这些条件对于海事应用来说是典型的，但包括空气-水界面中经历从干到湿再向后过渡的结构在内的基本实验似乎并不存在。本文旨在填补这一知识空白。我们提出了一个实验，其中一个钟摆悬挂在静止水位上方，然后暴露于具有不同波长的单色自由表面波。此外，还导出了一个降阶模型来计算摆的响应并帮助解释实验结果。摆的运动响应被证明在很大程度上取决于波浪周期是远低于还是高于摆的干燥自然周期。此外，模型中波幅的敏感性研究和实验中可变性的量化都表明，相对于传入波的可变性，钟摆运动响应的可变性增加。我们相信这个实验和结果为自由表面波中的流固耦合提供了一个有趣的基准。钟摆的属性和实验可在 doi:10.4121/13187594（Wellens 和 Bos，2020 年）作为开放数据获得。我们相信这个实验和结果为自由表面波中的流固耦合提供了一个有趣的基准。钟摆的属性和实验可在 doi:10.4121/13187594（Wellens 和 Bos，2020 年）作为开放数据获得。我们相信这个实验和结果为自由表面波中的流固耦合提供了一个有趣的基准。钟摆的属性和实验可在 doi:10.4121/13187594（Wellens 和 Bos，2020 年）作为开放数据获得。