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根据历史文献资料，对黄河在淮期间淮河入海河口的动力条件、地貌特征及其演变机制进行了研究。结果表明，历史时期因大量多泥沙黄河径流汇入，淮河河口径流量、输沙量增大，但不同时期输沙量又受黄河下游反复进行的沿程淤积的影响而有变化。淮河口是中等强度的潮汐河口，其往复潮流和沿岸流系统非常有利于入海泥沙扩散。淮河口呈上窄下宽的喇叭口形，口门内、外侧分别发育有大规模拦门沙及水下三角洲，河口段河道具有典型的弯曲河型，自18世纪以后口门宽度有增大的趋势。淮河口演变的机制是潮流界不断向下游迁移、河口不断向海延伸，而且潮流界下移距离远大于同期河口外延距离，河口段长度急剧缩短。为了适应径流、潮流消能的需要，河口段河型向曲流化发展、口门展宽。古淮河人海河口和现代黄河河口具有不同的动力地貌特性和演变机制，其间不能作简单类比。
According to the historical documents, the dynamic conditions, geomorphologic features and evolution mechanism of the Yellow River during the Huaihe River estuary estuary were studied. The results show that during the historical period, the runoff of a large number of sediment from the Yellow River and the increase of runoff and sediment load in the Huaihe River estuary increased. However, the sediment discharge in different periods changed due to the siltation along the Yellow River. Huaihe Estuary is a moderate tidal estuary, and its reciprocating tidal current and coastal flow system are very conducive to the proliferation of sediment into the sea. Huaihe Estuary was narrow and wide bell-shaped mouth, inside and outside the mouth were developed large-scale barricade sand and underwater delta, the estuary section of the river has a typical curved river, since the 18th century after the gate width has increased trend. The mechanism of the evolution of the Huaihe Estuary is that the tidal current continuously migrates to the lower reaches, the estuary continues to extend to the sea, and the distance of tidal current is much larger than that of the estuary at the same period. The length of the estuary is drastically shortened. In order to meet the needs of runoff and tidal current energy dissipation, the estuarine river type develops toward the meandering, and its mouth widens. The ancient Huaihe River estuary and the modern Yellow River Estuary have different dynamical geomorphological characteristics and evolution mechanism, during which no simple analogy can be made.