A new 1D coupled hydrodynamic discrete element model for floating debris in violent shallow flows

Abstract

The effect of floating objects has so far rarely been considered in flood modelling and risk assessment, despite having significant implications for structural design in flood-prone and coastal areas. In this work, a novel two-way method is proposed to fully couple a discrete element model to a hydrodynamic model to simulate complex debris-enriched flow hydrodynamics. The adopted hydrodynamic model solves the nonlinear shallow water equations (SWEs) using a finite volume shock-capturing numerical method. After being validated against an idealized analytical test, the new coupled model is used to reproduce flume experiments of floating debris driven by dam-break waves. The numerical results agree well with the experimental measurements, demonstrating the model’s capability in simulating the complex fluid–debris interactions induced by violent shallow flows.

Keywords:

• Coupled model
• discrete element model
• extreme hydraulic conditions
• floating debris
• Godunov-type finite volume method
• shallow water equations

Additional information

Funding

This work is partly funded by the UK Natural Environment Research Council (NERC) through the UK NERC SINATRA and TENDERLY projects (grant number NE/K008781/1) and WeACT project (grant number NE/S005919/1) and the National Natural Science Foundation of China (grant number 51579090).