The environmental transport of contaminants (organic matter, metals...) in surface waters is largely controlled by the behaviour of the particulate phase. Modelling the fate and behaviour of these pollutants therefore supposes to address a number of sediment transport issues.
In the field of sediment transport hydraulics, research at the department of water pollution control in recent years has especially addressed the following themes:

• handling heterogeneous particle size distributions as occurring in natural river streams (enhancement to the Engelund-Hansen computation procedure)
• computing particle settling velocity without distinction between Stokes regime and Newton regime
• composite roughness model
• assessing average shear conditions in narrow channel configuration (aspect ratio W/D<3) and application to the prediction of the stability of irrigation canals
• procedure for the computation of 1D suspended sediment transport capacity in alluvial rivers, building on Bagnold’s (1966) original ideas on the asymmetry of shear turbulence
• bursting-based dual-layer model for the computation of 2D suspended sediment transport

A recent development in this area examines the feasibility of predicting the actual value of the friction factor of any alluvial stream occurring in nature. This is notably based on a procedure to predetermine which type of bedforms (ripples, dunes, antidunes...) is likely to occur for a given set of hydraulic and sedimentary conditions.

Contact for further information: mikeverb@ulb.ac.be