Impact of Ship-Generated Waves on the Sediment Resuspension in Restricted Waterways

The ship-generated waves in restricted waterways can influence the behavior of sediment resuspension and bank erosion. This paper explores the case study considering the effect of ship-generated waves in restricted channels. A fully nonlinear Boussinesq model (FUNWAVE-TVD) is used to simulate the ship-generated waves. The sediment transport model adopted in FUNWAVE has been changed to incorporate the modified diffusion coefficients, deposition flux, and an explicit equation for settling velocity and critical shield parameter. The sediment transport model was validated against the experimental results of solitary waves in a wave tank, and model performance in shoreline geometry was reported. The implementation of the moving vessel in the numerical model and its impact on suspended sediment concentration were evaluated against the field measurements in the Falta stretch of the Hooghly river in Indian National Waterway 1. The error value in predicting the depth-averaged suspended sediment concentration by the FUNWAVE module was 97.6%, which has been significantly reduced to 16.3% based on the present modification. The parametric study of the ship waves in a typical restricted waterway of India revealed that the concentration of the sediments gradually decreases from the navigation channel to the river banks due to dissipation in the ship waves. The change in wave height and depth-averaged sediment concentration increases with the increasing depth Froude number. Finally, the impact on sediment transport due to different scenarios, such as the movement of two vessels in close proximity, the passage of vehicles coming from the opposite direction on the navigation channel, the influence of small draft vessels, and the bed morphology changes due to the multiple vessel movements are analyzed and reported.