MULTIPIR · Multiscale modelling of migration of pollutant particles in rivers
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2020-12-01 → 2022-11-30
- EU contribution
- €224,934
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Multiscale modelling of migration of pollutant particles in rivers
River pollution from fine-grained sediment (FGS) is an unsolved challenging environmental problem. A thorough understanding of FGS migration in rivers is critical in improving water quality in rivers and river management. To achieve this, a hybrid discrete element method (DEM) and lattice Boltzmann method (LBM) are firstly employed to systematically analyse transportation of FGS. The effects of fluid inertia, particle density and cavity size on the trap efficiency in the cavity are systematically investigated. The results show that three distinctive regimes can be identified using a dimensionless trap number: a resuspension regime, a fully trapped regime, and a continuous circulating regime. To investigate the migration behavior of FGS particles under higher Reynolds number, a discrete phase model (DPM) coupled with computational fluid dynamics (CFD) is also developed. The influence of particle properties, operating parameters, and various flume configurations on the flow status and migration behaviour is systematically analysed. Flume tests are performed to validate the developed models and further explore the migration behaviour of particles. The infiltration rate of the FGS particles dramatically increases when the particle density increases or fluid velocity decreases. Moreover, the shape of the cavity is found to have less effect on the infiltration rate. It is also found that the resuspension rate increases linearly with the growth of inlet velocity and decreases dramatically with the rise of the particle size and density. A GPU-enhanced DEM approach is also developed to explore the transportation behavior of shaped particles. It is found that the transportation of spherical particles involves the smallest particle retention number, mean residence time, and power consumption, while shaped particles lead to the larger particle retention number and higher power consumption. The combined numerical and experimental investigations provide a step-change in process understanding and model development underpinning future river pollution control initiatives.
Data: CORDIS, © European Union
Project objective
River pollution has become a serious environmental problem in the Europe and worldwide as it dramatically affects the freshwater quality and human health. A major source of chemical and physical pollution in rivers is small particles known as fine-grained sediment (FGS). Intensified agricultural practices and the associated increase in soil erosion in Europe has caused a shape increase in the supply of FGS to water streams. Consequently, the water quality in many rivers in Europe have deteriorated and are failing to meet minimum water quality standards. Hence, there is a urgent need to address the river pollution problem through a thorough understanding on how much supplied FGS infiltrates into the river bed and how much is resuspended and migrated at different hydrodynamic conditions, i.e. the dynamics of FGS. MULTIPIR takes an inter-disciplinary approach to tackle this challenge heads-on by combining the extraordinary experience of the researcher in erosion, sand production, hydraulics and computational fluid dynamics (CFD) with the expertise of the supervisor in coupled discrete element methods with CFD (DEM-CFD) and solid-liquid flows. A combined experimental and numerical investigation on the migration of FGS in the river will be performed, from which multiscale models will be developed to predict the infiltration and re-suspension of FGS at the microscopic level and the transport of FGS at different hydraulic conditions at the macroscopic scale. Using the developed model, a river pollution control map will be developed to guide the river managements. It is for the first time that advanced engineering approaches, e.g. DEM-CFD and advanced imaging techniques, are employed to address the challenging environmental problem and to develop a science-based river pollution control strategy that can benefit European citizens and beyond.
Original text from CORDIS.
Participants
- UNIVERSITY OF SURREY · GuildfordCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union