Hydrodynamic analysis of a waterjet propelled underwater vehicle in vertical plane

As a new type of autonomous underwater vehicle (AUV), a waterjet propelled underwater vehicle (WPUV) which is equipped with waterjet propulsion system and has a wing-blended body is proposed in this paper. The waterjet sucks water from outside through an inlet duct and discharges it out through a nozzle. The inlet duct has a great influence on hydrodynamics of the WPUV when the waterjet pump is working. In order to obtain the hydrodynamics of the WPUV and performance of the waterjet pump, Computational Fluid Dynamic (CFD) technology is used to simulate them synchronously in vertical plane at different cruising speeds, different rotating speeds of pump rotor and different attack angles. After simulating, forces, torques and pressures on the vehicle's hull and waterjet components are obtained, including longitudinal forces, vertical forces, pitching moment, and thrust of the waterjet pump, etc. From these results, other parameters of the WPUV can be calculated, such as waterjet power, endurance time, and sail range. The results of hydrodynamic analysis are the basis of maneuverability analysis and provide a helpful reference to other new types of WPUV. Copyright © 2014 by the International Society of Offshore and Polar Engineers (ISOPE).