Experimental investigation into the flow around a manoeuvring LNG carrier on shallow water

The objective of this research project is to supply information on the hydrodynamical flow around a manoeuvring vessel on shallow water. The flow patterns and the resulting forces and moments acting on the LNG carrier with twin gondola aft-body as a consequence of a drifting motion are studied. Hydrodynamic forces and moments acting on a ship change remarkably depending on the water depth. Accurate prediction of the hydrodynamic derivatives of vessels on shallow water and the ability to quantify the effect of form variations is needed. Information from these experiments is used to better understand the effect of water depth. The flow observation, wave profile measurements and force' measurements contribute to the comprehension of the observed phenomena and can be used to validate and accelerate the development of potential flow, Reynolds Averaged Navier Stokes (RANS) and semi-empirical simulation codes. The experiments consist of towing a model of a 300 meter LNG carrier in the MARIN shallow water basin in water depth to draught ratios. State-of-the-art flow measurements with Particle Image Velocimetry (PIV) measurements were carried out up and down stream of the hull at several planes along the ship. Some representative flow fields are presented to demonstrate the influence of the water depth on the flow around the model. Besides the flow measurements the hydrodynamic forces and moments were measured.