Influence of gaps between multiple floating bodies on wave forces

The present study aims to give general hints about hydrodynamic interaction s for water wave diffraction on a super large floating structure composed o f a large number of box-shaped modules with many small gaps in between. And meanwhile, it also aims to seek for an effective way to take the gap influ ence into consideration without numerical difficulties existing in conventi onal methods. An asymptotic matching technique is exploited by virtue of th e smallness of gaps. Formal potential solutions are established for the nea r field around the gap ends and the far field away from gap ends, respectiv ely, and the unknowns in those solutions are uniquely determined by asympto tic matching. The eigen-function expansion method is used for the outer far field and a series of pulsating sources at each gap end is introduced to s imulate the gap influence. Strong hydrodynamic interaction is observed and a new resonant phenomenon, the mechanism of which differs absolutely from a ny known ones, is revealed in the present study. Sharp peak responses for b oth vertical and horizontal wave-exciting forces on each block are found ar ound some special resonance frequencies, which depend on the draft of the s tructure and the gap width. The present results are of practical significan ce to the design of links (connectors) of modules for super large floating structures. And the importance is also closely related to the hydro-elastic ity analysis for super large floating structures, in which local loads may be as important as the integrated loads.