Research on the Hydrodynamic and Cavitation Performance of Semi-Balanced Twisted Rudders

Abstract

In this study, we designed a new, semi-balanced, twisted rudder to reduce the surface cavitation problem of medium-high-speed surface warships. Based on the detached eddy simulation (DES) with the Spalart-Allmaras (SA) model (SA-DES) and the volume of fluid (VOF) method, the hydrodynamic and cavitation performances of an ordinary semi-balanced rudder and semi-balanced twisted rudder at different rudder angles were numerically calculated and compared using the commercial computational fluid dynamics (CFD) software STAR-CCM+ with the whole-domain structured grid. The calculation results showed that, under the same working conditions, the maneuverability of the semi-balanced twisted rudder basically remained unchanged compared with that of the ordinary semi-balanced rudder. Furthermore, the surface cavitation range of the semi-balanced twisted rudder was much smaller, and the inception rudder angle of the rudder surface cavitation increased by at least 5° at the maximum speed. In conclusion, the semi-balanced twisted rudder effectively reduced the cavitation of the rudder surface without reducing the rudder effect and exhibited excellent anti-cavitation performance.

Keywords

Surface cavitation / Semi-balanced twisted rudder / Inception rudder angle / Cavitation range / Hydrodynamic performance