Gap Resonance of Fixed Floating Multi Caissons

Generally, numerous marine and offshore structures are composed of a number of modules which introduce narrow gaps between the multi-modules arranged side by side. The interaction between water waves and floating structures excites complex wave runup in the gaps and wave forces on the adjacent modules. In this study, free surface oscillations in twin narrow gaps between identical floating rectangular boxes are investigated by establishing a 2D viscous flow numerical wave tank based on a Constrained Interpolation Profile (CIP) method. Tangent of Hyperbola for INterface Capturing (THINC) method is employed tocapture the free surface. The rigid floating bodies are treated by Virtual Particle Method (VPM). The incident waves are generated by an internal wave maker. For the fixed modules cases, the computational results of wave height in narrow gaps are found in good coincidence with the available experimental measurements, especially for the resonant frequencies. When multi caissons free from heave motion, the free surface elevations are decreased dramatically and the resonant frequencies tend to higher wave numbers