Effect of the Bow Shapes on the Sinkage of Ships

The scope of knowledge about sinkage currently suggests that this hydrodynamic effect is caused by the changes occurred in the dynamic pressure field of a ship-hull when it sails. Consequently, this hydrodynamic effect could be optimized by changing the hull forms design, and at this respect, it has been stated that the bow shapes might be the most related part of the hull forms towards sinkage. The aim of this work is to continue studying the geometry-sinkage issue, deepening in how the bow shapes can influence this phenomenon. Based on the towing tests results of a ship database it was confirmed that sinkage leads to significant drag increase, which in some cases can be up to more than the 20% of drag, reinforcing the need of studying how to address its optimization. As well, the idea of the key effect of the bow shapes on the sinkage of ships was refused based on the following results. Firstly, there were two pair of hulls which share the particularity of just differing in the bow—one of each had a bulbous bow while the other presented a straight bow—and each pair showed similar levels of sinkage for both designs. After that, the sinkage acquired in two loading cases by a double bow ferry ship was studied showing similar results. These results have been complemented with the numerical study of the problem with Star-CCM+.