Comparative resistance calculations for SLICE/SWATH hulls

Abstract

Comparative resistance calculations are performed for SLICE and SWATH hulls. For the purposes of this study, the primary difference between these two hull types is in the underwater pods. It is assumed that both ship types have identical surface piercing struts, speed, and displacement. The underwater pods are continuous for the SWATH design and discontinuous for the SLICE. Resistance calculations are based on I.T.T.C. skin friction, empirical regression of existing experimental data for form drag, and surface singularities distribution for wavemaking. Results are presented for two cases, length limited where the overall length between the two hull types remains constant, and diameter limited where the pod diameter remains constant. Parametric studies in terms of pod geometry, separation distance, ship speed, displacement length ratio, and draft indicate that a SLICE hull may offer decreased resistance compared to a similar SWATH, depending on the range of the above design parameters. (AN)