The Three-Dimensional Dynamic Characteristics on the South of Subei Radiation Shoal Waters

Based on the high precision terrain datas , high resolution FVCOM(Finite-Volume Coastal Ocean Model) numerical model was established to simulation for tide current and study three-dimensional dynamic characteristics of the south of Radiation shoal waters. Result show that transverse circulation was easy to produce in channel and groove. The vorticity and helicity computation method was applied in the area for the frist time. Transverse circulation and helical flow characteristics of typical sections were preliminary studied, and result show the quantitative evidence for the existence of the Spiral flow.Deep groove is not always appear double reverse spiral flow structure, it changes with the main flow velocity. Shoal grooves appear, a main spiral flow structure, and show great adaptability to the terrain, which is the reflection of the spiral flow to the terrain maintain mechanism .