Zhao, D.; Guo, C., and Su, Y., 2016. Hydrodynamic performance of ichthyoid rudder at different rudder angle settings.

This paper presents the first calculation of the open-water hydrodynamic performance of ordinary and ichthyoid rudders in a viscous flow field using the computational fluid dynamics method as well as an investigation of the lift and resistance coefficients of the two rudders. First, an ichthyoid rudder was formed by adjusting the shape of an ordinary rudder to mimic the shape of a fish tail. Subsequently, open-water tests of ordinary and ichthyoid rudders were conducted, and the maneuverability of the two rudders was compared at different rudder angle settings. The results of the theoretical calculations show that the ichthyoid rudder has obvious advantages over the ordinary rudder in improving the lift coefficient and postponing the stall phenomenon at greater critical rudder angles. This paper also presents calculations of the force and moment of the two rudders at different rudder angle settings and compares the results of these calculations. By comparing the wake fields of the two rudders at different rudder angle settings, our study provides a theoretical basis for the improved ship maneuverability observed with the ichthyoid rudder.