On self-propulsion assessment of marine vehicles

Estimation of ship self-propulsion is important for the selection of the propulsion system and the main engine so that the ship can move forward with the required speed. Resistance characteristics of the vessel or the open-water performance of a propeller only are not usually enough to assess the working conditions of the ship. Both in numerical simulations and in experiments; there is a need to treat the propulsion system and the hull as a whole for a better estimation of the self-propulsion parameters. In this study, the self-propulsion points of one submarine (DARPA Suboff) and two surface piercing vessels (KCS and DTC) were obtained with methods based on computational fluid dynamics (CFD) approach. The self-propulsion points were also calculated by a classical engineering approach that makes use of the empirical relations that may be found in the literature. The results were evaluated with respect to the experiments and numerical results generated by other researchers in this field. It was found that the self-propulsion points of traditional ship forms can be very closely approximated with a classical engineering approach, given the basic geometric and the hydrostatic properties of the hull and the propeller.