Numerical And Experimental Studies Of Gap Resonance Between Twin Floating Heaving Bodies

It has become a hot research topic to study the hydrodynamics of the narrow gap between two adjacent floating bodies.However,at present,the research on the gap wave resonance phenomenon by viscous flow is still under the assumption that the floating bodies are fixed.In this paper,we considered the wave gap resonance when the twin boies which are rigid connected or seperated are allowed to heave freely under the incident wave.A two dimensional numerical wave tank was established based on self-programming.Then the reliability of the numerical wave tank was proved by verifying the performance of wave generation and dealing with twin fixed bodies and single heaving body.The hydrodynamic response of the rigid-connected and seperated heaving bodies at different frequencies of incident waves is studied,including the resonant frequency,average wave height in the gap,motion response and force on the floating bodies.The numerical simulation results of the seperated heaving bodies are in good agreement with the model test than rigid-connected bodies.Due to the frictional damping effect in the model test,the amplitude of the floating motion of the heaving bodies measured by the test is small than numerical result.It is found that the width of the gap between two floating bodies and the draft of the the twin bodies have an effect on the resonance response in the narrow gap and the wave force on the bodies.This paper explores the influence of the existence of narrow gap on the heaving motion floating body and finds that the existence of the narrow gap has a great influence on the heaving motion of the floating body.It is found that due to the existence of the narrow gap,the motion amplitude and velocity of the rigid-connected bodies are smaller than that of the single heave motion body.In the case of the incident wave number greater than the resonance,due to the action of the water body in the narrow gap,the motion amplitude and velocity of the rigid-connected bodies are larger than that of the single heave motion body.This paper also analyzes the difference between rigid-connected and seperated heaving bodies.When the floating body is rigid-connected,the wave surface elevation in the narrow gap is not much different from the horizontal force received by seperated heaving bodies,but the vertical forces are significantly different.However,the fixed results are significantly different from the results of rigid-connected and seperated heaving bodies in all cases.