Multibody Interactions of Floating Bodies with Time-Domain Predictions

Abstract

The applications of the three-dimensional transient panel code ITU-WAVE based on potential theory is further extended to take into account the multibody interactions in an array system using linear and square arrays. The transient wave-body interactions of first-order radiation and diffraction hydrodynamic parameters are solved as the impulsive velocity potential to predict Impulse Response Functions (IRFs) for each mode of motion. It is shown that hydrodynamic interactions are stronger when the bodies in an array system are close proximity and these hydrodynamic interactions are reduced considerably and shifted to larger times when the separation distances are increased. The numerical predictions of radiation (added-mass and damping coefficients) and exciting (diffraction and Froude-Krylov) forces are presented on each floating bodies in an array system and on single structure considering array as single floating body. Furthermore, the numerical experiment shows the hydrodynamic interactions are more pronounced in the resonant frequency region which are of important for fluid forces over bodies, responses and designs of multibody floating systems. The present numerical results of ITU-WAVE are validated against analytical, other numerical and experimental results for single body, linear arrays (two, five and nine floating bodies) and square arrays of four truncated vertical cylinders.