Modeling Large Wood Transport in Semi-Congested Regime with Multiple Entry Points

Abstract

Wood transport during flood events can increase inundation risk and should be included in numerical models to estimate the associated residual risk. This paper presents the application of a fully Eulerian model that considers floating wood as a passive superficial pollutant through the adaptation of the advection–diffusion equation. A set of experiments is performed in a sinusoidal flume with a contraction to model semi-congested wood transport. The variation of the log release position replicates the possible variability of large wood entrainment during real events. The experiments are used to validate the numerical model, providing a comparison of the wood mass transport. Different release modes are also tested. The model predicts the position of the released logs and the overall transported mass, independently of the release position and modes, with an accuracy that varies along the flume length and across the flume axis. The analysis of the experimental and numerical transport velocity shows that modulation of the transport velocity is needed to ensure adequate model performances for semi-congested conditions.

Keywords

• large wood
• advection–diffusion
• Eulerian model
• semi-congested transport