GeodesicODIS is a finite volume fluid dynamics code for simulating global oceanic flow in icy satellites and other bodies. GeodesicODIS currently solves the Laplace Tidal Equations (LTE) assuming a 1-layer free-surface or subsurface ocean of uniform thickness.
GeodesicODIS is a new version of the finite difference code ODIS. ODIS solved the LTE over a rectangular structured lat-lon mesh (Hay and Matsuyama, 2017), while GeodesicODIS does the same over an unstructured mesh based on the icosahedral-geodesic grid (Hay and Matsuyama, 2018).
To get started with ODIS, copy the repository to your local machine and run make.
Three prerequisites are required for ODIS: the Fortran-95 SHTOOLS library, Intel's c++ compiler with MKL, and the HDF5 library.
SHTools is a high-performance spherical harmonics library used in ODIS to decompose the tidal displacement at the ocean surface into spherical harmonics, which is required for subsurface ocean calculations and free-surface calculations that include ocean self-gravity.
The Intel c++ compiler is a highly optimized compiler for numerical applications written in c++ on Intel processors. We make use of the compiler and the Intel Math Kernel Library (MKL) to perform calculations involving sparse matrices. In ODIS, interpolation from the geodesic to lat-lon grid is performed with a single sparse matrix multiplication using MKL.
HDF5 is an optimized file format for storing large amounts of numerical data. ODIS makes use of this format to write all of its numerical output to memory.
ODIS can be run after running 'make'. Just run "./ODIS" with the default input file to begin subsurface ocean simulations on Enceladus.
GeodesicODIS 1.11 (November 2019): Velocity nodes moved to control volume edges, vastly improved stability, first boundary implementation.
GeodesicODIS 1.10 (April 2019): Parallelized code, better grids, optimization and simplification of code.
GeodesicODIS 1.0 (November 2018): Recorded in branch HayMatsuyama2018.