Simulation of turbid underflows generated by the plunging of a river

When the density of sediment-laden river water exceeds that of the lake or ocean into which it discharges, the river plunges to the bottom of the rece iving water body and continues to Row as a hyperpycnal flow, These particle -laden underflows, also known as turbidity currents, can travel remarkable distances and profoundly influence the seabed morphology from shoreline to abyss by depositing, eroding, and dispersing Large quantities of sediment p articles, Here we present a new approach to investigating the transformatio n of a plunging river flow into a turbidity current. Unlike previous worker s using experimental and numerical treatments, we consider the evolution of a turbidity current from a river as different stages of a single flow proc ess. From initial commotion to final stabilization, the transformation of a river (open channel flow) into a density-driven current (hyperpycnal flow) is captured in its entirety by a numerical model. Successful implementatio n of the model in laboratory and field cases has revealed the dynamics of a complex geophysical flow that is extremely difficult to observe in the fie ld or model in the laboratory.