Hydrodynamic performance of DC372 under different spans and water depths

Geometrical and environmental conditions influence the hydrodynamic performance of a catamaran. The separation distance between the demi-hulls of a catamaran (i.e., the interference factor or span) is one of the main effective geometrical parameters, and water depth to draft ratio (i.e., h / T ) is an important environmental condition. Therefore, in the present study, the hydrodynamic performance of the Delft catamaran (DC372) is numerically investigated under various spans and the water depth to draft ratios. To accomplish this, the Reynolds-Averaged Navier-Stokes (RANS) solver within the OpenFOAM CFD toolbox was employed. The numerical results are appropriately validated against the existing numerical and experimental data. Based on the major results, sinkage significantly decreases when the water depth to draft ratio increases from h / T = 2 to deep water, particularly for span 0.5. In the case of span 0.9, sinkage at h / T = 3 is obtained higher compared to h / T = 2. Increasing the spans from 0.5 to 0.9 significantly decreases the total resistance, particularly for Froude numbers higher than 0.2. Finally, the generalized design optimization framework for selecting the span is presented.