Prediction of Flows around Ship-shaped Hull Sections in Roll Using an Unsteady Navier-Stokes Solver

Summary

Scope of Work:
Note: This study is part of a broader project “FPSO Roll Motions” (MMS Project 406).

The objective of the research is to develop a robust and reliable computational tool to predict hull motions and the resulting hydrodynamic loads, with emphasis on roll. More precisely, the research aims to perform systematic studies on grid dependence of the results of the developed methods, and to investigate the effects of hull geometries and the presence of the bilge keels on the reduction of hull motions.

A two-dimensional numerical scheme for solving the unsteady Euler equations in the context of propulsor flows was developed by the Ocean Engineering Group in the University of Texas at Austin (Choi 2000; Choi and Kinnas 2001; Choi and Kinnas 2003). Later, the numerical scheme has been modified to include the effect of viscosity and was named NS2D. It was applied to simulate hull motions and to predict corresponding hydrodynamic loads in Kakar (2002) and Kacham (2004) with simplified hull geometries and assumptions. In this study, the two-dimensional numerical scheme is further improved, and applied to problems with more complex hull geometries. The solver is later extended into three dimensions, which will be mentioned as NS3D hereafter.