A Review of Numerical Modelling of Morphodynamics in Braided Rivers: Mechanisms, Insights and Challenges

Abstract

In the past decade, the numerical modelling of braided river morphodynamics has experienced a significant advance due to the increasing computer power and the development of numerical techniques. Numerical models are quite efficient in exploring scenarios with different settings, and they can be applied to investigate the complicated physics laws of natural braided rivers and manage complex river engineering problems. However, braided river models are far from fully developed, e.g., the representation of flow and sediment transport, model sensitivity, essential effects of sediment transport, bank erosion and vegetation, and require intensive refinement and validation to enhance their prediction accuracy. The recent application of advanced field measurement techniques offers model development a new chance by providing abundant measurement data of a high quality. The present study reviews the essential mechanisms and applications of typical braided river models; compares their accuracy; discusses the recent progress, advantages and shortcomings; and illustrates the challenges and future research trends.

Morphological Model for Erosion Prediction of India’s Largest Braided River Using MIKE 21C Model

“…The vertical changes in the Brahmaputra River are monitored through river cross section surveys, conducted using ADCP (Acoustic Doppler Current Profiling) in watercovered areas or conventional cross section surveys. In dry sections of the river, surveys are performed using traditional topographical methods or airborne LiDAR (Light Detection and Ranging) surveys (Leyland, et al, 2017;Hu et al, 2023). Besides topographic and bathymetric data, acquiring data on discharge, sediment load (both bed load and suspended load), and the grain size distribution of bed and bank materials is crucial (Karmaker and Dutta, 2016;Ashley et al, 2020).…”