NUMERICAL STUDY ON THE HYDRODYNAMIC PERFORMANCE OF A SELF-PROPELLED SUBMERSIBLE

In this paper, a numerical study on the hydrodynamic performances of an autonomous unmanned vehicle (AUV) was carried out. For its propulsion, a model of a new seven-bladed propeller defined as stock propeller was made. Several numerical simulations were carried out, namely open water test, towing resistance test, and self-propulsion test. This study focuses on the thruster's ability to perform its task correctly for improved use. The examination of the propeller characteristics in open water test exhibits a better efficiency and the thrust can be improved by slightly adjusting the pitch distribution of the propeller. In the towing resistance test, wake behind the body was also investigated by studying axial velocity field in many transversal planes. Added to the self-propulsion test results, the evolution of the thrust magnitude in the wake by moving the thruster plane axially reveals that the required thrust level is reached far behind the actual position of the thruster disc. It is found that the ratio of thrusts with or without the presence of the body is equal neither to unity nor to the torque ratio.