Abstract

Abstract: Since the introduction of the first nuclear powered submarine the USS Nautilus in 1955, propulsive thrust for nuclear powered submarines has been provided by geared steam turbine drive. Steam turbines however, operate inefficiently at part load, adversely affecting propulsive efficiency at speeds submarines spend the majority of their service life at. A recent trend for surface combatants is to move towards all-electric propulsion, which offers many advantages, including improved operating efficiency at part load. However, due to the inherent limitations of submarine propulsion design the application of electric drive to submarines is still in contention.

This presentation uses multi-objective evolutionary optimisation and inverse simulation to compare the merits of different propulsion concepts, with a focus on overall system efficiency. In particular, electrical drive and hybrid drive are compared to the traditional steam turbine mechanical drive. Trade-offs in propulsion system design are discussed as well as the effect of control strategy optimisation on the final system design and performance. Conclusions are drawn on the most efficient propulsion system design for future submersible combatants.