Numerical simulation of hull installation of a novel outboard dynamic inlet waterjet

The present thesis investigates the propulsive performance and the installation effects of a novel waterjet concept for sustainable marine propulsion. This innovative system is called Outboard Dynamic-Inlet Waterjet (ODW) and it features a unique operational mode, being completely submerged and benefiting from an axial dynamic inlet and propulsive nozzle. Unlike traditional waterjets, the ODW’s biggest advantage is that it operates in an axial, uniform captured stream tube, resulting in higher efficiency and thrust. The primary objective of this work is to investigate the installation of the propulsive system and its mutual effect with the hull, by analysing the dynamics and performance. A total of 13 installation locations of the engine at different submergence and longitudinal positions are studied in steady-state Reynolds Averaged Navier-Stokes equations. Following an accurate mesh validation process, the simulations yield satisfactory results. The analysis of the Net Vehicle Force highlighted the most forward installation position as the most advantageous, where the net force coefficient exceeds the ideal value of 0.285. However, not all performance parameters are maximised in this configuration: while a reduction in hull drag is observed, the available Net Propulsive Thrust also decreases. Conversely, the worst configuration is found slightly ahead with respect to the trailing edge of the hull, at non-dimensional coordinate (-0.7788 ; -0.1657), where minimum performance is recorded and cavitation occurs even under design conditions.