Abstract
Two-dimensional numerical model is developed. The effect of diurnal inequality and river discharge on the mixing of density current in estuary is investigated. Numerical results coincide almost with observed ones for the higher isohaline but for the lower isohaline the difference between numerical and observed results is large. The effect of the diurnal inequality on saline intrusion is classified into two patterns. This classification is explainable by the new parameter, which is defined by the tidal amplitude. When the river discharge exceeds 1000 m3/s, the intrusion of saline water is almost stopped.
