Abstract
Fluid motions of water surface elevations in narrow gaps at joint parts of a caisson-type breakwater are investigated by theoretical considerations and laboratory experiments. It has been reported that wave heights in such as the narrow gaps extremely increased in the cases of specific incident wave conditions. From the viewpoint of an occurrence of fluid resonance, we examine to derive frequency response curves on the water surface elevations in the gaps by use of an asymptotic matching method under a linear water wave theory. Then, we discuss the change of non-dimensional resonant wave numbers when the wave heights in the gaps approach their maximums with different rates of a gap width and a gap length by a systematic calculation of the frequency response curves. Consequently, the theoretical non-dimensional resonant wave numbers obtained from the curves have agreedwell with the experimental ones. And the variation of non-dimensional resonant wave numbers with the different rates has been quantitatively evaluated by a regression curve.
