Structure of the strong tidal jet in the naruto strait

Abstract

In order to clarify the structure of the strong tidal current at the Naruto Strait in the Seto Inland Sea of Japan, the sea-level values were observed in the strait and the current measurements were made with an Acoustic Doppler Current Profiler (ADCP). The tidal volume transports for M2 and S2 tides were about 74×103 and 26×103 m3 sec−1, respectively. The horizontal profile of the velocity at the phase of the strong tidal current compares favorably with a theoretical profile of the two-dimensional steady turbulent jet except for the side parts of the profile. Moreover, the entrainment rate of the surrounding water into the strong tidal jet was estimated from the difference of mass flux between two cross-sections at the strait, the entrainment rate and entrainment constant for both the northward and southward flows being about 1.3–2.5×10−4m−1 and about 0.03–0.05, respectively.