应用势流粘性修正模型的双浮体间窄缝共振数值模拟研究

随着时代的发展，海洋工程设备的建设愈发地受到国内外的重视。无论是船舶操作时的旁靠、靠岸等操作，还是海上平台的月池等结构，都会出现窄缝结构。该结构在入射波的侵扰下，当处于特定入射波频率时可能会出现共振现象，在某些位置会产生较大共振波高以及产生较大的波浪力，对生产安全都有着严重的挑战。该现象称之为窄缝共振现象。现有的针对该现象的模拟研究发现，传统势流模型在面对该情况下相较于准确的粘流模型而言，对响应波高的计算会出现明显的高估情况，这是由于势流模型忽略了流体粘性因素所导致的。但是准确的粘流模型计算速率较低，无法大规模应用在实际的工程设计之中。

本文根据此窄缝共振现象展开研究，通过弱阻尼理论对全非线性圆形势流模型波浪水池进行粘性修正，针对修正系数的选取提供不同的数值及方案，并探究修正系数对于共振频率处的修正效果。结果表明在针对响应波高进行计算的结果中，修正模型为常数，修正系数选取为0.0092的修正模型得到了最好的拟合性。本文还探究了模型对波浪力计算的能力，以及探究了双浮体的受力情况。我们得到结论，该模型对于双浮体受到的横荡力，在第一模态共振频率处有着较为明显的修正效果，而随着频率的增加，该模型计算的结果会大于势流模型计算结果，并且系统整体的受力也随之增大。

非线性因素在双浮体共振现象中也是不可忽视的因素，本文探究了该修正模型相较于势流模型的计算结果的修正效果，并将其结果与OpenFOAM的粘性流结果比对，发现由于网格密度选取问题，共振频率相较于OpenFOAM的计算结果会发生偏移。并且研究还发现，算例的共振频率随着非线性的增强，逐渐向右偏移。最后文章还探究了在不同的非线性条件下，窄缝双浮体结构物的受力情况。

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