Numerical Modeling of Suspended Cohesive Sediment Transport and Mud Profile Deformation

• Published in: Journal of coastal research Vol. SI; no. 56; pp. 663 - 667
• Main Authors: Soltanpour, M., Jazayeri, S. M. H.
• Format: Journal Article
• Language: English
• Published: Fort Lauderdale Coastal Education & Research Foundation (CERF) 01.01.2009; Allen Press Inc
• Subjects: Coastal Evolution; Coasts; Cohesion; Cohesive sediments; Dynamical systems; Erosion; Erosion rate; Erosion rates; Fluid mechanics; Kaolinite; Mathematical analysis; Mathematical models; Modeling; Mud; Sediment concentration; Sediment transport; Sediments; Settling velocity; Shear stress; Simulation; Simulations; Suspended sediments; Suspended solids; Water depth; Water levels; Wave action; Waves
• ISSN: 0749-0208; 1551-5036

A cross-shore numerical model is introduced for the simulation of suspended cohesive sediment transport and mud profile change under wave action. Partial deferential equation of 2D vertical advection-diffusion is solved for prediction of cohesive sediment transport where the deposition and erosion rates are introduced as appropriate sink and source functions. The deposition and erosion rates are derived from the empirical relationships in accordance with the bed shear stress and the settling velocity of suspended sediment is calculated from the local sediment concentration. A dynamic mesh, where the physical space in Cartesian coordinates is replaced by a computational σ-coordinate system, is employed considering that both water level and bed surface are time dependent. Finite volume method is applied to solve the discretized equation. Comparisons between the simulated concentration profiles with the results of laboratory experiments conducted on kaolinite show good agreements. Beach profile change is also calculated using the conservation equation of sediment mass. The cross-shore mud profile model is verified comparing the calculated profiles with a laboratory wave-flume experiments.