Major Research Development of a sediment transport model that considers the 3D dynamics of fluid mud

In ports and harbors located near estuaries, siltation (deposition of mud) in shipping routes and basins could pose an issue in some circumstances. Therefore, it is important to develop a sediment transport model that can accurately predict mud transport processes for efficient maintenance and management of ports and harbors (e.g., dredging shipping routes and basins). It has been reported that the fluid mud formed on top of the consolidated bed affects the result of acoustic sounding using multibeam sonar, etc. Therefore, we must also understand and predict the formation processes of fluid mud that occurs with the accumulation of suspended mud. In this study, we developed a sediment transport model that can consider the vertical structure of high-concentrated mud including fluid mud and the flow structure depending on the mud concentration.
 We successfully simulated the formation processes of fluid mud and the flow structure depending on the mud concentration, by implementing into the model the following key factors for simulating the movement of high-concentrated mud: (i) flocculation of mud particles and hindered settling of high-concentrated mud; (ii) buoyancy effect caused by the mud concentration gradient; (iii) self-weight consolidation of fluid mud; and (iv) non-Newtonian fluid movement of fluid mud.