Author(s): Yu Yao, Wenrun He, Ruichao Du, Changbo Jiang
Linked Author(s): Yu Yao
Keywords: Wave breaking, wave setup, tidal current, fringing reef.
Abstract: Recent field studies on coral reef hydrodynamics have increasingly recognized the importance of tide in dominating the reef regional circulation. In this study, a series of laboratory experiments were performed in a wave-current flume to investigate the maximum wave-induced setup on the reef flat in the absence/presence of the tidal current. Experimental results were reported for a variety of regular wave and steady current conditions by using an idealized fringing reef model. Wave setup was found to reduce along the reef flat when shoreward current was present, but such decline was not obvious with seaward current. Compared to the absence of current, the maximum wave setup on the reef flat was consistently smaller during the shoreward current (flood tide) whereas it was always larger during the seaward current (ebb tide). Moreover, wave setup on the reef flat decreased with increasing flowrate of shoreward current while it increased with increasing flowrate of seaward current. Tidal current affecting the magnitude of wave setup on the reef flat were due to the changes of both bottom friction and momentum advection in the surfzone momentum balance
Year: 2017