MixtSedFOAM

beach, dike

• velocity
• pressure
• volume fractions of 3 phases (air, water and sediment)
• turbulence: k & ε or omega

• Hybrid mixture/2-phase flow theory
• Suspension mass balance (continuity)
• Suspension momentum balance (RANS)
• Viscosity closure (suspension rheology)
• Turbulence closure (customized mixture k-ε model)
• SPM mass balance (unsteady adv.-diff. eq.)
• Particle drift velocity closure
• Roughness closure

• traditional boundary conditions for RANS solvers
• the sediment bed can be made part of the computational domain

• domain geometry
• boundary conditions
• material properties

cartesian

unstructured FVM

• Can deal with very detailed wave-current-sediment interactions
• Useful as numerical laboratory to generate data which cannot be measured experimentally

• high-resolution required around the sediment bed interface, makes computation heavy and thus limits the applications to small scale problems

Parameters:

1. Fluid density & viscosity
2. Particle density
3. Settling velocity
4. Nikuradse roughness
5. Mixture rheology parameters

Procedure

• 1-2: usually known
• 3-5: start from known, modify if necessary

7 testcases in Ouda, M. (2019). Multiphase modelling of sediment transport and bed erosion for the study of coastal morphodynamics. PhD thesis, Dept. Of Civil Enigineering, KU Leuven, 229 pp.