Physical theory for near-bed turbulent particle-suspension capacity
Joris T. Eggenhuisen1, Matthieu J. B. Cartigny2, and Jan de Leeuw11Department of Earth Sciences, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, the Netherlands 2National Oceanography Centre, Waterfront Campus, European Way, Southampton, SO14 3ZH, UK
Received: 17 Jun 2016 – Accepted for review: 22 Jun 2016 – Discussion started: 28 Jun 2016
Abstract. The inability to capture the physics of solid-particle suspension in turbulent fluid flow is holding back application of multiphase computational fluid dynamics techniques to the many problems involving particle suspension in nature and society. We present a theory for particle suspension capacity near no-slip frictional boundaries of turbulent flows. The suspension capacity parameter Γ includes universal turbulent flow scales and material properties of the fluid and particles only. Comparison to measurements shows that Γ = 1 gives the upper limit of observed suspended particle concentrations in a broad range of flume experiments and field settings. The condition of Γ > 1 coincides with complete suppression of coherent turbulent structures near the boundary in Direct Numerical Simulations of sediment-laden turbulent flow. The theory outperforms previous empiric relations when compared to data. It can be applied as a concentration boundary condition in modelling studies of dispersion of particulates in environmental and man-made flows.
Eggenhuisen, J. T., Cartigny, M. J. B., and de Leeuw, J.: Physical theory for near-bed turbulent particle-suspension capacity, Earth Surf. Dynam. Discuss., doi:10.5194/esurf-2016-33, in review, 2016.