Hydrodynamics characteristics of the small ships rudders

Abstract

The estimation of the hydrodynamics characteristics of the small ships rudders is an important issue in the initial design process. The manoeuvring performance depends on the type and geometry of the rudder. The control forces and moments generated by the rudder deflection can be calculated on the basis of the hydrodynamics characteristics of the rudder. A short description of the Mordvinov theoretical model is presented in this paper, in order to determine the hydrodynamics characteristics of a small ship rudder, with the propeller and hull influences. On the basis of the control forces and moments, the optimum position of the rudder stock and the selection of the steering gear can be performed. Using the Mordvinov method, the computer code PHP NM-MAN-HC was develop at the Research Centre of the Naval Architecture Faculty of “Dunarea de Jos” University of Galati. This computer code is integrated in the software platform PHP (Preliminary Hydrodynamics Performance) and is used for didactic applications and practical research activities in the small ship design process