【摘要】 黄河自从1996年人工改道取北汊入渤海以来，河口沙嘴整体呈北偏趋势。现有对河口演变规律的研究多聚焦河口水沙与海洋动力的相互作用，对科氏力这一持续驱动因素的作用机制尚缺乏系统认识。本文基于水动力数值模拟，从科氏力作用的角度，模拟研究了有无科氏力作用下黄河三角洲近岸潮流结构与河口泥沙入海输运扩散特征的差异。模拟显示科氏力驱动近岸潮流呈往复式运动，并在河口外侧形成一个封闭椭圆形高流速区（流速>0.8 m/s），同时在河口北侧的五号桩附近形成M₂分潮无潮点，泥沙在沙嘴北侧扩散范围明显大于无科氏力情景。无科氏力作用时，近岸潮流主要表现为放射状往复运动，河口外侧未出现封闭高流速区，五号桩周边无潮点亦消失，河口泥沙向远海纵向扩散范围更大。结果表明，科氏力通过增强近岸涨落潮流横向运动强度促使泥沙向南北两侧输运，形成的M₂无潮点“低位能区”增大了河口与M₂无潮点之间的势能梯度，提高了落潮流时河口泥沙向北的输运强度，加之河口沙嘴北侧岬湾化程度增加进一步弱化局部潮流动力，使得更多泥沙在此区域淤积，这些因素的耦合效应共同促进了黄河口沙嘴北偏演进过程。更多还原

【Abstract】 Since the artificial diversion of the Huanghe River into the Bohai Sea via the northern channel in 1996,the estuary sand spit has exhibited a distinct northward migration trend. Current research on estuarine evolution primarily focuses on the interplay between fluvial water-sediment inputs and marine hydrodynamic forces, while a systematic understanding of the role of the Coriolis force as a persistent driver remains lacking. Through hydrodynamic numerical modeling, this study investigates the influence of the Earth’s Coriolis force on tidal current structures and sediment transport patterns in the nearshore region of the Huanghe River Delta by comparing scenarios with and without Coriolis effects. The simulation shows that the Coriolis force drives the nearshore tidal current to move in a reciprocating manner, and forms a closed elliptical high velocity area（velocity > 0.8 m/s） outside the estuary. At the same time, the M₂ tidal amphidromic point is formed near the No.5 pile on the north side of the estuary, and the sediment diffusion range on the north side of the mouth is significantly larger than that without Coriolis force. In the absence of Coriolis force, the nearshore tidal current is mainly radial reciprocating motion, and there is no closed high velocity area outside the estuary. The amphidromic tide point around the No.5 pile also disappears, and the longitudinal diffusion range of estuarine sediment to the open sea is larger. These findings indicate that the Coriolis force enhances lateral sediment transport by intensifying the transverse movement of flood and ebb currents. The formation of the M₂ amphidromic point, acting as a “low potential energy zone”, increases the potential energy gradient between the estuary and the amphidromic point, thereby strengthening northward sediment transport during ebb tides. Furthermore, the increased indentation of the northern bayline weakens local tidal dynamics, promoting additional sediment deposition in this area. The synergistic effects of these mechanisms collectively drive the northward evolutionary process of the Huanghe River estuary sand spit.更多还原