1. Thetis coastal ocean model: discontinuous Galerkin discretization for the three-dimensional hydrostatic equations.
- Author
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Kärnä, Tuomas, Kramer, Stephan C., Mitchell, Lawrence, Ham, David A., Piggott, Matthew D., and Baptista, António M.
- Subjects
GALERKIN methods ,COMPUTATIONAL fluid dynamics ,OCEANOGRAPHY ,OCEAN circulation ,HYDROSTATIC equilibrium - Abstract
Unstructured grid ocean models are advantageous for simulating the coastal ocean and river–estuary–plume systems. However, unstructured grid models tend to be diffusive and/or computationally expensive, which limits their applicability to real-life problems. In this paper, we describe a novel discontinuous Galerkin (DG) finite element discretization for the hydrostatic equations. The formulation is fully conservative and second-order accurate in space and time. Monotonicity of the advection scheme is ensured by using a strong stability-preserving time integration method and slope limiters. Compared to previous DG models, advantages include a more accurate mode splitting method, revised viscosity formulation, and new second-order time integration scheme. We demonstrate that the model is capable of simulating baroclinic flows in the eddying regime with a suite of test cases. Numerical dissipation is well-controlled, being comparable or lower than in existing state-of-the-art structured grid models. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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