Deformable Riverbeds: A Numerical Study

A mathematical model that comprehensively captures the behavior of mobile riverbed deformation encompassing all pertinent effects was developed. The underwater slope reformation process with the generatrix aligned along the flow velocity in the model was considered. A numerical model was introduced to calculate the flow involving a deformable bottom, and the model's validation was established through rigorous analysis of the experimental findings. This research confirms the suitability of the proposed mathematical and numerical model for describing deformations in uneven and unsteady river flows, including the movement of dredging slots and channel quarries. The minimal equation count and reliance on empirical constants demonstrate the efficiency of the model. The model's predictions aligned firmly with the experimental data, although the optimal values of the empirical coefficients varied slightly across different experiments. Hence, there is a call for further investigation to derive more universally applicable closure relationships for the model. The importance of validating the model with reliable field data and its potential extension to accommodate hydraulically diverse soils is emphasized. Such an extension is feasible because of the concentration transfer equation, which enables independent calculations for particle fractions of varying sizes as long as the total particle concentration in the stream remains within reasonable limits. This dedicated research contributes to understanding riverbed deformation, advancing accurate modeling, and managing riverine environments.