Rudder effectiveness and course-keeping stability in shallow water: A theoretical model

Article type: Research Article

Authors: Hess, F.

Affiliations: Applied Mathematics Department, University of Adelaide, Australia

Abstract: This paper presents a hydrodynamic model for the rudder action of a ship in shallow water, which is based on two ideas. 1. The ship-rudder system is considered as a slender wing, and the rudder acts as a trailing-edge flap. 2. The shallow-water effects can be modelled by Newman’s theory for a slender body between two parallel walls. The resulting theoretical model leads to predictions for the sway force and yaw moment derivatives with respect to sideslip angle, yaw rate and rudder deflection in water of arbitrary but constant depth. The model is limited to single-rudder ships. Theoretical results for rudder force and moment, course-keeping stability and turning radius are compared with experimental data from the literature.

DOI: 10.3233/ISP-1977-2427602

Journal: International Shipbuilding Progress, vol. 24, no. 276, pp. 206-221, 1977