A novel hydrodynamic layout of front vertical rudders for maneuvering underwater supercavitating vehicles

摘要

Owing to the complex hydrodynamic characteristics of the water/cavity/vehicle systems, supercavitating vehicles (SVs) feature slope-discontinuous force characteristics at the afterbody, presenting challenges to the hydrodynamic control of such maneuverable and highly agile vehicles. In this paper, the disadvantages of the existing SV hydrodynamic layout are revealed via rudder efficiency analysis, and a novel hydrodynamic layout of front vertical rudders for high agility maneuvering SVs is proposed. In this layout, the vertical rudders are fixed behind the cavitator at the bow. The rudder efficiency is improved remarkably without increasing the degree of freedom of the cavitator, and the valuable space in the cavitator is reserved. From the unit step response characteristics, it is observed that using the novel hydrodynamic layout affords approximately twice the sideslip angle and five times the yaw rate compared to those using the existing layout. Free motion experiments are carried out with an SV with a preset vertical rudder angle, and the feasibility of the proposed hydrodynamic layout is validated.