CFD Analysis of a Sailing Ship in Quartering Waves
Examensarbete för masterexamen
Applied mechanics (MPAME), MSc
Predicting the motions of a ship in waves has traditionally been done using methods based on potential theory. However, these methods are limited in the phenomena they can take into account and the level of information they produce. In these cases CFD can play an important role. In this report a CFD program called ReFRESCO is used to study the motion and force response of a ship sailing in regular quartering waves with 6 degrees of freedom. The ship in question is the KRISO container ship (KCS). First the necessary methodology is developed by incrementally increasing the number of degrees of freedom for a ship in bow quartering waves. The drift problem that is associated with surge, sway and yaw motion is solved by using conceptual spring models. Once a methodology is found, it is applied to a number of different cases with varying wave frequencies and amplitudes, both in stern and bow quartering seas. It is concluded that this method predicts the ship motion and surge force with reasonable accuracy. The forces in sway and yaw are also investigated, though no validation can be done as no experimental data is obtainable for comparison.
CFD , Seakeeping , Ships