Tanker Hull in Regular Waves: CFD Comparison to Existing Experiments

Kurzfassung

The evaluation of a ship's performance in seaways is crucial for its efficient operation including passenger comfort and fatigue strength. With growing computing power, proper CFD predictions become increasingly attractive. During the EU project "Extreme Seas" an extensive experimental test campaign with a model of a chemical tanker has been conducted. In this paper, the motion of the vessel in regular waves within the Stokes-II regime are assessed by means of CFD-Simulation and compared to the experimental results. Moreover, the influence of the surge motion on the overall ship response is investigated by conducting the simulations with two enabled degrees of freedom as well as with a spring system to additionally enable surge motions and reproduce the experimental setup. Comparison to experimental data is performed by means of response amplitude operators for heave and pitch. The simulations show a reasonable agreement with the experimental results for both investigated numerical setups. However, the CFD results indicate that a restricted surge motion leads to an overestimation of the pitch response for long waves up to the peak of the response amplitude operator. In contrast to that, the heave motion is barely influenced by the surge motion. These findings are scrutinized through application of the Boundary Element Method confirming the potential accuracy improvement when including surge motions in the seakeeping simulations.