An unstructured-grid, nonhydrostatic, GVC ocean model Part I: Model description and application of vertical hybrid coordinates to internal solitary waves

Le résumé fourni par la source

We present a nonhydrostatic ocean model with a horizontally unstructured, C-grid and a moving, generalized vertical coordinate (GVC) designed for the simulation of nonhydrostatic processes in realistic ocean domains. The GVC system can represent any of the well-known z-level, terrain-following, or isopycnal coordinates while also being able to employ hybrid vertical coordinates. In this paper we outline the specific steps needed to incorporate the GVC system into the unstructured, C-grid, nonhydrostatic, z-coordinate SUNTANS model of Fringer et al. (2006). The approach is adapted from the nonhydrostatic, isopycnal-coordinate method of Vitousek and Fringer (2014), yet our model differs from that implementation through the development of a conservative momentum advection scheme and a positivity-preserving layer height scheme for horizontally unstructured grids. We validate the momentum advection implementation with simulations of a turbulent channel flow and demonstrate the advantages of the hybrid vertical coordinate approach over z- or terrain-following coordinates through simulations of internal solitary waves and the associated bottom boundary layer instability.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.