A wetting and drying algorithm with a combined pressure/free-surface formulation for non-hydrostatic models

作者：Funke S W^*; Pain C C; Kramer S C; Piggott M D

来源：Advances in Water Resources, 2011, 34(11): 1483-1495.

DOI：10.1016/j.advwatres.2011.08.007

• Wetting and drying
• Non-hydrostatic Navier-Stokes equations
• Finite element method
• Implicit time integration

A wetting and drying method for free-surface problems for the three-dimensional, non-hydrostatic Navier-Stokes equations is proposed. The key idea is to use a horizontally fixed mesh and to apply different boundary conditions on the free-surface in wet and dry zones. In wet areas a combined pressure/free-surface kinematic boundary condition is applied, while in dry areas a positive water level and a no-normal flow boundary condition are enforced. In addition, vertical mesh movement is performed to accurately represent the free-surface motion. Non-physical flow in the remaining thin layer in dry areas is naturally prevented if a Manning-Strickler bottom drag is used. The treatment of the wetting and drying processes applied through the boundary condition yields great flexibility to the discretisation used. Specifically, a fully unstructured mesh with any finite element choice and implicit time discretisation method can be applied. The resulting method is mass conservative, stable and accurate. It is implemented within Fluidity-ICOM [1] and verified against several idealized test cases and a laboratory experiment of the Okushiri tsunami.

• 出版日期2011-11