When two vessels in a side-by-side configuration are under wave actions, fluid resonance occurs in a narrow gap between two vessels, termed ‘gap resonance’, leading to large free-surface responses. Large free-surface responses due to gap resonance can induce large relative motions and drift forces by both vessels, which influences operational safety. The present study aims at investigating the free-surface response near resonance in a narrow gap between two fixed, identical barges with square corners numerically and experimentally. Gap resonance is driven by three typical incident wave conditions including beam sea, quartering sea, and head sea. In light of the fact that the potential-flow theory overestimates the response in the gap, a potential-flow model with energy dissipation effects is developed based on the boundary element method. A dissipation surface is devised at the bottom opening as well as two end openings of the gap. Both linear and quadratic damping terms associated with laminar boundary layer wall friction and flow separation from sharp corners are accounted for. Physical experiments of gap resonance excited by irregular waves with different significant wave heights and peak periods are carried out and used for calibration and validation of the potential-flow model. Nonlinear correlation is observed between the incident wave amplitude and resonant gap response, which is predicted with satisfactory agreement by the developed potential-flow model. In-depth discussion on the mode shapes is made. It is found that the first mode is predominant in the beam sea, and the natural modes exhibit standing wave behaviors. Under quartering sea and head sea excitations, the second and third modes dominate over other modes. Waves propagate slowly along the gap in the head sea condition. Under the quartering sea excitation, the first and second modes propagate along the gap, but the third mode exhibits standing wave behavior, indicating the quartering sea response is a transition between head sea and beam sea. The significance of the present study is threefold. Firstly, the experimental measurements provide reference results for numerical simulation. Secondly, a simple but effective damping model to suppress unrealistic free-surface response near resonance is developed. Lastly, this work gives an insight into the spatial structure and dominance of natural modes under different wave conditions.

当两个并排配置的容器处于波浪作用下时，在两个容器之间的狭窄间隙中发生流体共振，称为“间隙共振”，从而导致较大的自由表面响应。由于间隙共振而产生的较大的自由表面响应会导致两个容器产生较大的相对运动和漂移力，从而影响操作安全性。本研究旨在通过数值和实验研究在两个固定的，相同的带有方形角的驳船之间的狭窄缝隙中，共振附近的自由表面响应。间隙共振是由三种典型的入射波条件驱动的，包括波束海，直角海和顶海。鉴于势能流理论高估了间隙中的响应，基于边界元方法建立了具有能量耗散效应的势能流模型。在间隙的底部开口和两个端部开口处设计有耗散表面。与层状边界层壁的摩擦和与尖角的流动分离有关的线性和二次阻尼项都被考虑了。进行了由具有不同有效波高和峰值周期的不规则波激发的间隙共振的物理实验，并将其用于势流模型的校准和验证。观察到入射波幅度与共振间隙响应之间存在非线性相关性，这通过已开发的势流模型可以令人满意地预测。对模式形状进行了深入的讨论。发现第一模式在束海中占主导地位，自然模式表现出驻波行为。在四分之一海和上海激发下，第二和第三模式优于其他模式。波浪在海面条件下沿着缝隙缓慢传播。在四分之一海激发下，第一和第二模式沿着间隙传播，但是第三模式表现出驻波行为，表明四分之一海响应是在海浪和海浪之间的过渡。本研究的意义是三方面的。首先，实验测量为数值模拟提供了参考结果。其次，建立了一个简单但有效的阻尼模型来抑制共振附近不现实的自由表面响应。最后，这项工作提供了对不同波浪条件下自然模式的空间结构和优势的见解。在四分之一海激发下，第一和第二模式沿着间隙传播，但是第三模式表现出驻波行为，表明四分之一海响应是在海浪和海浪之间的过渡。本研究的意义是三方面的。首先，实验测量为数值模拟提供了参考结果。其次，建立了一个简单但有效的阻尼模型来抑制共振附近不现实的自由表面响应。最后，这项工作提供了对不同波浪条件下自然模式的空间结构和优势的见解。在四分之一海激发下，第一和第二模式沿着间隙传播，但是第三模式表现出驻波行为，表明四分之一海响应是在海浪和海浪之间的过渡。本研究的意义是三方面的。首先，实验测量为数值模拟提供了参考结果。其次，建立了一个简单但有效的阻尼模型来抑制共振附近不现实的自由表面响应。最后，这项工作提供了对不同波浪条件下自然模式的空间结构和优势的见解。本研究的意义是三方面的。首先，实验测量为数值模拟提供了参考结果。其次，建立了一个简单但有效的阻尼模型来抑制共振附近不现实的自由表面响应。最后，这项工作提供了对不同波浪条件下自然模式的空间结构和优势的见解。本研究的意义是三方面的。首先，实验测量为数值模拟提供了参考结果。其次，建立了一个简单但有效的阻尼模型来抑制共振附近不现实的自由表面响应。最后，这项工作提供了对不同波浪条件下自然模式的空间结构和优势的见解。