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Edit this text for your title. MEK 4450 Marine Operations. Edit this text for your sub-title Presenter name, location, date etc. Kværner ASA / DNV, Fall 2012. Numerical Tools / Analysis Software. Why numerical tools ? More accurate and detailed description Why comercial tools :
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Edit this text for your title MEK 4450 Marine Operations Edit this text for your sub-title Presenter name, location, date etc. Kværner ASA / DNV, Fall 2012
Numerical Tools / Analysis Software Whynumericaltools? More accurate and detaileddescription Whycomercialtools: Time consuming to produceinhouse Better qualitychecks (?) Clients acceptance
Numerical models Hydrostatic / stabilitymodels (e.g. AutoHydro, Hydro D) Basic hydrodynamic analyses (e.g. WADAM, WAMIT) Time domaincoupeled analyses (e.g. SIMO) CFD Beam theory (e.g. Orcaflex, Riflex) FEM
Hydrostatic model • INPUT • Wet hull shape • Mass • COG • OUTPUT • Floating condition • Stability margins • MODEL • Geometry: stripes • Mass and COG • Archimedes • Buoyancy and moments Use with care for non- standard aplications Purpose made For normal ship Hull and normal operations Quick and simple to use
Floating object in waves - standard theory • INPUT • Wet hull shape • Mass distribution • OUTPUT • Motion, pressure ++ • Transfer function • Postprocessing • MODEL • Geometry: panels • Mass matrix • Inviscid • Incompressible • Vessel: rigid body • Incident waves • Viscous damping neglected • Couplings and nonlinearity neglected Purpose made For normal ship Hull and normal operations Quick and accurate solutions when relevant
Time domain simulation program • INPUT • (Hydro)dynamic characteristics • Links, wires, beams etc • Environment • OUTPUT • Time series for motions, forces etc • Design values: post processing • MODEL • Rigid body motions • Forces from environments and links • Quality of coefficients? • Time consuming Stepping forward in time. Runge Kutta etc Realistic modeling of marine operations
CFD • INPUT • Boundary geometry and conditions • Initial conditons • Fluid and turbulence parameters • OUTPUT • Fields for velocity, pressure etc at different time steps • Integrated quantities • MODEL • Viscous fluid • Turbulence • Bodies with prescribed motion • Time consuming • Floating bodies? Stepping forward in time. Runge Kutta etc Realistic modeling of fluid flow Accurate (?) calcs of coefficients