甬舟水道潮不对称性与水沙输移特征OACSTPCD

Based on the measured hydrologic and sediment data in the Zhoushan sea area and the simulation results of tidal current and sediment mathematical model,the characteristics of tidal dynamics and water-sediment transport in multi-channel waterway between Ningbo and Zhoushan were analyzed.The analysis of the dynamic causes of the tidal asymmetry shows that the shallow water component which caused by the bottom friction and island blocking,combined with astronomical component is the power supply leading to the tide asymmetry.The Euler residual current plays a major role in the tidal current asymmetry.The asymmetry of tidal discharge determines the migration of tidal residual current and net tidal volume.In deep troughs,the asymmetry of tidal current dominated by Euler residual current mainly controls the asymmetry of tidal discharge,whereas Euler residual current and Stokes residual current jointly determine the asymmetry of tidal discharge in the shoal.The sediment concentration in Zhoushan Bay,which is controlled by the sediment concentration in the source area and affected by tidal current,shows weak fluctuation,on account of which the suspended sediment transport is controlled by the tidal asymmetry.In deep troughs,the suspended sediment transport is dominated by the Euler residual current,but in the shoal is determined by the Euler residual current and Stokes residual current.The tidal pumping effect has a non-decisive impact on the net sediment transport.