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Theory Manual

The OASIS Theory Manual provides the mathematical formulations behind each simulation module. It is maintained as a LaTeX document and distributed as a PDF.

:material-download: Download Theory Manual (PDF)

Contents

The theory manual covers:

Chapter Topic
§1 Introduction — scope, notation and goals
§2 Coordinate systems and rigid body dynamics — reference frames, Euler angles, rotation matrices, Newton–Euler equations
§3 Waves — regular waves, irregular spectra (JONSWAP), directional spreading
§4 Hydrostatics — linear restoring forces and non-linear Froude–Krylov on the instantaneous wetted surface
§5 Hydrodynamics — Cummins equation, radiation/diffraction, first- and second-order excitation, QTFs, Morison wind/current
§6 Mooring and towing lines — governing PDE, spectral element method (SEM), tension models (Rayleigh, viscoelastic), external forces, boundary conditions, quasi-static initial conditions
§7 Seafloor interaction — flat, inclined and complex bathymetry projection algorithms, ground normal and friction forces
§8 Springs and connectors — 6-DOF spring model, deformation measurement, elastic/damping/friction forces
§9 Winches — mechanical model, controllers
§10 Oscillating water columns — pneumatic chamber and turbine model
§11 Wind turbines — OpenFAST coupling interface
§12 Sinking — progressive flooding model
§13 Time integration — adaptive BDF2, ESDIRK, Newton–Raphson iteration, error estimation
§14 Coupling — global state vector, RHS evaluation order, weak coupling strategy

Building from Source

The LaTeX source is in docs/theory-manual/OASIS_TheoryManual.tex. To compile:

cd docs/theory-manual
pdflatex OASIS_TheoryManual.tex
pdflatex OASIS_TheoryManual.tex